Photometric variability of 14 PMS stars in the NGC 7000/IC 5070 complex

Photometric variability of 14 PMS stars in the NGC 7000/IC 5070 complex

Sunay I. Ibryamov and Evgeni H. Semkov Institute of Astronomy and NAO, Bulgarian Academy of Sciences, BG-1784 Sofia Department of Theoretical and Applied Physics, University of Shumen, BG-9712 Shumen
sibryamov@astro.bas.bg Institute of Astronomy and NAO, Bulgarian Academy of Sciences, BG-1784 Sofia
Abstract

New photometric data from CCD multicolour observations of 14 pre-main sequence stars during the period from 2013 April to 2015 September are presented. The studied objects are located in the field of ’Gulf of Mexico’ in the NGC 7000/IC 5070 star-forming complex. The stars from our study exhibit different types of photometric variability in all optical passbands. Using our long-term observations and data published by other authors, we tried to define the reasons for the observed brightness variations. On the basis of our new data previously unknown periodicity in the light curve of the star LkH 189 (2.45 days) was registered.

stars: pre-main sequence, stars: variables: T Tauri, star: individual: V521 Cyg, V752 Cyg, V1538 Cyg, V1539 Cyg, V1716 Cyg, V1957 Cyg, V2051 Cyg, LkH 186, LkH 187, LkH 189, LkH 191, [KW97] 53-11, [KW97] 53-23, [KW97] 53-36
\tocauthor

S. Ibryamov and E. Semkov \papertypeSubmitted on; Accepted on

1. Introduction

Studies of pre-main sequence (PMS) stars give an opportunity to understand the early stages of stellar evolution and to test stellar evolution scenarios. Depending on their initial mass, PMS stars pass through different periods of stellar activity. The most prominent manifestations of this activity are changes in the star’s brightness with various periods and amplitudes.

PMS stars are rare among field stars, because during the PMS evolutionary phase the stars spend less then 1% of its life. PMS stars are separated into two main types, low mass (M 2M) T Tauri stars (TTS) and the more massive (2M M 8M) Herbig Ae/Be stars (HAEBES). Both TTS and HAEBES still contracting towards the main sequence.

TTS are associated with dark nebulae, molecular clouds, obscured regions, and are grouped in T associations. The main characteristics of TTS are their strong irregular photometric variability and emission line spectra (Joy 1945). TTS are divided into two sub-classes: classical T Tauri stars (CTTS) and weak-line T Tauri stars (WTTS). Most of the features that characterize each sub-class suggest that accretion disks surround CTTS whereas they must have almost disappeared (at least their inner parts) in WTTS (see Bertout 1989; Ménard & Bertout 1999).

According to Herbst et al. (2007), variability of CTTS can be due to rotating hot spots on the stellar surface. CTTS also often shows irregular variations with large photometric amplitudes up to 2-3 mag, associated with high variable accretion from the circumstellar disk onto the stellar surface. The variability of WTTS is due to cool spots or groups of spots on the stellar surface. The photometric amplitudes of this variability are about 0.03-0.3 mag, but in extreme cases reach to 0.8 mag in the -band. The variability of WTTS can be due to flare-like variations in - and -band also. Flares are random with different sized amplitudes, as there is no periodicity. Usually, the rise of brightness is quick and occurs over short time scales.

The large amplitude drops in the brightness in the light curves are commonly observed in the early types (G, F) of TTS and HAEBES. These stars show non-periodic deep Algol-type minima and photometric amplitudes up to 2.8 mag in -band. The observed drops in the brightness last from days to some weeks and are caused by variable extinction from circumstellar dust or clouds (Voshchinnikov 1989; Grinin et al. 1991; Herbst et al. 2007). This group of PMS stars with intermediate mass is known as UXors and their prototype is the star UX Orionis. In very deep minima, the colour indices of UXors often becomes bluer (so called ’blueing effect’ or ’colour reverse’) (see Bibo & Thé 1990). It is generally accepted that the origin of observed drops in the brightness and the blueing effect are due to variations of the colomn density of dust in the line of sight to the star (Dullemond et al. 2003).

The stars from our study are located in the dense molecular cloud L935, known as ’Gulf of Mexico’ in the NGC 7000/IC 5070 complex. The NGC 7000/IC 5070 complex are thought to be parts of a single large HII region W80. The distance to this region, determined by Laugalys & Straižys (2002) is 600 pc. ’Gulf of Mexico’ is a region with active star formation and contains many PMS objects (see Armond et al. 2011; Findeisen et al. 2013; Bally et al. 2014; Poljancic Beljan et al. 2014). The PMS stars included in the present study are revealed in previous studies of the ’Gulf of Mexico’ as H emission stars, flare stars from UV Cet type, TTS or HAEBES.

The present paper is a part of our long-term multicolour photometric study of the PMS stars in the region of ’Gulf of Mexico’. The results from our previous studies of PMS stars in this field have been published in Semkov et al. (2010, 2012, 2014), Poljančić Beljan et al. (2014), Ibryamov et al. (2015a), and Ibryamov et al. (2015b). Section 2 gives information about telescopes and cameras used and data reduction. Section 3 describes the obtained results and their interpretation.

2. Observations and Data reduction

The presented photometric data were carried out in the period from 2013 April to 2015 September. The observations were performed with four telescopes: 2- Ritchey-Chrétien-Coudé (RCC), the 50/70-cm Schmidt and the 60-cm Cassegrain telescopes of the Rozhen National Astronomical Observatory in Bulgaria and the 1.3-m Ritchey-Chrétien (RC) telescope of the Skinakas Observatory111Skinakas Observatory is a collaborative project of the University of Crete, the Foundation for Research and Technology, Greece, and the Max-Planck-Institut für Extraterrestrische Physik, Germany. of the University of Crete in Greece. The total number of the nights used for observations is 84. A log of the observing periods and telescopes used is given in Table 1.

Telescope Nr of observations Time span
2-m RCC 23 04.07.2013 06.09.2015
1.3-m RC 4 17.09.2013 12.08.2015
50/70-cm Schmidt 41 10.04.2013 03.09.2015
60-cm Cassegrain 16 15.05.2013 21.07.2014
Table 1: Photometric CCD observations of the field of ’Gulf of Mexico’ with the different telescopes

The observations were performed with four different types of CCD cameras: VersArray 1300B at the 2-m RCC telescope, ANDOR DZ436-BV at the 1.3-m RC telescope, FLI PL16803 at the 50/70-cm Schmidt telescope, and FLI PL09000 at the 60-cm Cassegrain telescope. The technical parameters and specifications for the cameras used, observational procedure, and data reduction process are given in Ibryamov et al. (2015b). The photometric limit of our data obtained with the 2-m RCC and the 1.3-m RC telescopes in - and -band is about 20.5 mag and for the data collected with the 50/70-cm Schmidt and the 60-cm Cassegrain telescopes is about 19.5 mag.

All frames were taken through a standard Johnson-Cousins () set of filters. All data were analyzed using the same aperture, which was chosen to have a 4 radius, while the background annulus was taken from 9 to 14. As a reference, the comparison sequence reported in Semkov et al. (2010) was used. The mean value of the errors in the reported magnitudes are 0.01-0.02 mag for - and -band data, 0.02-0.06 mag for -band data, and 0.02-0.09 mag for -band data.

3. Results and Discussion

The photometric results for 14 stars obtained in our study and their interpretation are presented in the section. All stars exhibit photometric variability in optical passbands. Our data are a continuation of the long-term photometric investigations of these stars published in Poljančić Beljan et al. (2014) and Ibryamov et al. (2015a).

The data for the studied objects are presented in Table 2. Star identifiers used in this paper are marked in boldface. Figure 1 shows a three-colour images of the field of ’Gulf of Mexico’, where the positions of the stars from our study and the recently erupting FUor star V2493 Cyg (see Semkov et al. 2010, 2012, 2014; Miller et al. 2011) are marked. The images were obtained with the 50/70-cm Schmidt telescope of Rozhen NAO on 2012 September 04 (the left image) and on 2014 August 19 (the right image).

The stars from our study shows bursts and/or fades events in their light curves. These events are defined as follows. In the case that the star most of the time spends at high light during our study, the declines in the brightness are interpreted as fades. Respectively, if the star most of the time spends at a low light, the observed increases in the brightness are interpreted as bursts.

Figure 1: Three-colour images of the field of ’Gulf of Mexico’. The positions of the stars from our study and the recently erupting FUor star V2493 Cyg are marked. The images were obtained with the 50/70-cm Schmidt telescope of Rozhen NAO on 2012 September 04 (the left image) and on 2014 August 19 (the right image).

The 2MASS magnitudes of the studied stars were used to construct the two-colour diagram and to identify stars with infrared excess, indicating the presence of a disk. Fig. 2 shows the location of main sequence (brown belt) and giant stars (orange belt) from Bessell & Brett (1988), and the classical T Tauri stars location (green belt) from Meyer et al. (1997). A correction to the 2MASS photometric system was performed following the prescription of Carpenter (2001). The three parallel dotted lines show the direction of the interstellar reddening vectors determined for the ’Gulf of Mexico’ region by Straižys et al. (2008). In Fig. 2 the stars are designated using the numbers from Table 2. The stars lying to the right of the middle vector indicate the presence of a infrared excess. Due to the photometric variability, the positions of stars in Fig. 2 may vary around the displayed values.

Table 3 contain the mean photometrical magnitudes and colour indices for the stars from our study.

Nr GCVS HBC [KW97] LkH 2MASS ID
1 V521 Cyg 299 53-26 188 J20582381+4353114 20 58 23.81 +43 53 11.45
2 V752 Cyg 53-30 J20583359+4403354 20 58 33.60 +44 03 35.50
3 V1538 Cyg J20575750+4350089 20 57 57.51 +43 50 08.95
4 V1539 Cyg 720 53-9 185 J20575986+4353260 20 57 59.86 +43 53 26.00
5 V1716 Cyg J20580611+4353011 20 58 06.12 +43 53 01.17
6 V1957 Cyg J20575651+4352362 20 57 56.52 +43 52 36.29
7 V2051 Cyg J20574880+4350236 20 57 48.80 +43 50 23.60
8 723 53-24 186 J20581961+4353545 20 58 19.62 +43 53 54.52
9 724 53-25 187 J20582154+4353449 20 58 21.54 +43 53 44.96
10 725 53-27 189 J20582400+4353546 20 58 24.01 +43 53 54.61
11 301 53-42 191 J20590581+4357030 20 59 05.82 +43 57 03.08
12 53-11 20 58 03.00 +43 50 42.00
13 53-23 J20581951+4353449 20 58 19.52 +43 53 45.00
14 53-36 J20584756+4402574 20 58 47.52 +44 02 59.29

General Catalogue of Variable Stars (Samus et al. 2009); Herbig & Bell (1988); Kohoutek & Wehmeyer (1997); Herbig (1958); 2Micron All-Sky Survey (Skrutskie et al. 2006).

Table 2: Designations and coordinates of the stars from our study
Figure 2: The versus diagram for the stars detected in all 3 bands in 2MASS catalogue.
Star
V521 Cyg 12.11 12.93 13.76 15.03 1.66 0.84 1.26
V752 Cyg 14.98 15.89 16.61 17.48 1.63 0.72 0.87
V1538 Cyg 15.00 16.04 17.00 18.38 2.00 0.95 1.38
V1539 Cyg 13.51 14.51 15.55 16.90 2.04 1.04 1.35
V1716 Cyg 15.01 16.36 17.51 19.07 2.51 1.16 1.56
V1957 Cyg 14.57 15.43 16.26 17.50 1.70 0.83 1.24
V2051 Cyg 13.93 15.56 16.61 18.12 2.68 1.05 1.52
LkH 186 14.60 16.07 17.38 19.00 2.77 1.31 1.63
LkH 187 14.72 16.23 17.61 19.26 2.90 1.38 1.67
LkH 189 13.97 15.29 16.54 18.21 2.57 1.25 1.67
LkH 191 11.58 12.19 12.87 13.98 1.29 0.68 1.11
KW97 53-11 16.18 18.65 - - - - -
KW97 53-23 14.99 16.92 18.55 20.33 3.57 1.66 2.01
KW97 53-36 11.63 11.88 12.28 13.05 0.65 0.40 0.78

=2.54.

Table 3: Mean photometrical magnitudes and colour indices for the stars from our study

3.1. V521 Cyg

Variability of V521 Cyg was discovered and the star was classified as a RW Aurigae type by Hoffmeister (1949). The author reported that the photographic magnitude of the star vary from 14.30 to 16.60 mag. The star is included in the list of H emission-line star published in Herbig (1958). The author determined the photographic magnitude of the star =15.00 mag and its spectral type K0.

Filin (1974) presented observations of V521 Cyg obtained during the period 1969–1971 in system close to . The author registered slowly fluctuations in the star’s brightness in the interval 14.50–15.10 mag, as these fluctuations are characterized with deep drops in the brightness of V521 Cyg from the Algol type. Chavarría-K. et al. (1989) observed the star in photometric system and concluded that it is PMS star.

Herbst & Shevchenko (1999) observed V521 Cyg during the period 1986–1997 and determined the amplitude of its photometric activity =1.77 mag, average stellar magnitude =13.74 mag, and colour indices =0.58, =1.25 and =1.18 mag. Mitskevich & Pavlenko (2001) presented the light curve in -band of the star for the period 1999 July–October. It is seen that for about 20 days (in 1999 August), the star faded by 0.85 mag. The star spend about 5 days in minimum light state whereafter in next 70 days the star’s brightness gradually returned to the previous maximum level. The authors suggest that the reason for the decline in brightness of V521 Cyg is probably obscuration from circumstellar clouds of dust. In the presented colour indices and of the star is not observed bluing effect, because the registered minimum from Mitskevich & Pavlenko (2001) is relatively shallow.

Grankin et al. (2007) conducted long-term study of V521 Cyg during the period 1986 June–2003 September. The authors presented the light curve in -band of the star with brightness variations from 13.37 to 14.70 mag. Non-linear dependence of colour index versus stellar magnitude is present in Grankin et al. (2007).

In / diagram V521 Cyg is situated in the upper right-hand corner, close to the intrinsic T Tauri line in the CTTS location (Laugalys et al. 2006). Poljančić Beljan et al. (2014) determined the period of V521 Cyg, which is found to be 503 days. The cause of the period found is likely precession of the circumstellar disk or eclipses from a second component or by clouds of gas and dust orbiting the star.

The light curves of V521 Cyg from all our CCD observations (Poljančić Beljan et al. 2014; Ibryamov 2015a; and the present paper) are shown in Figure 3. In the figure, circles denote CCD photometric data obtained with the 2-m RCC telescope, diamonds – the photometric data collected with the 1.3-m telescope, triangles – the photometric data acquired with the 50/70-cm Schmidt telescope, and squares – the photometric data taken with the 60-cm Cassegrain telescope. The results of our recent multicolour CCD observations of V521 Cyg are summarized in Table 4222The tables with photometric CCD observations and data of the stars from our study only available at the Online material of the present paper.. The columns contains data (DD/MM/YYYY format) and Julian data (J.D.) of the observations, magnitudes of the star, telescope and CCD camera used.

Figure 3: CCD light curves of V521 Cyg for the period 1997 June–2015 September

The brightness of V521 Cyg during all period of our observations 1997–2015 vary in the range 11.78–12.85 mag for -band, 12.55–14.05 mag for -band, 13.32–14.89 mag for -band, and 14.49–16.69 mag in -band. The observed amplitudes are =1.07 mag, =1.50 mag, =1.57 mag, and =2.20 mag.

It can be seen from Fig. 3 that the star spends most of the time at high light. During our photometric monitoring, several fading events of V521 Cyg are registered. Ibryamov et al. (2015a) described seven deep declines in the brightness observed in all bands. The drops in the brightness are non-periodic and have different duration and amplitudes. It is possible to suggest the existence of a frequent deep fading events during periods with insufficient data. The new data shows one fading event observed in the beginning of 2015 with amplitudes 0.40 mag in -band, 0.48 mag in -band, 0.57 mag in -band, and 0.81 mag for -band.

The results obtained during our long-term study support the hypothesis of variable extinction as a reason for variability of V521 Cyg (Mitskevich & Pavlenko (2001) and Grankin et al. (2007)). The large amplitudes of observed declines in the brightness of the star (Fig. 3) are indication of UXor-type variability and the deep fading events presumably are result of circumstellar dust or clouds obscuration.

The measured colour indices , , and versus the stellar magnitude during the period of our observations are plotted in Fig. 4. Nevertheless of the large amplitude of variability, the substantial bluing effect is not seen on the figure. A possible explanation of this phenomenon is that the declines in the brightness at different periods are caused by clouds of dust and particles of various sizes. It can be supposed that in this case we observe eclipses from a combination of clouds with different structure rotating in orbits around the star.

Figure 4: Relationship between magnitude and the , , and colour indices of V521 Cyg in the period 19972015

The light curves of V521 Cyg look very similar to light curves of FHO 27, which was classified as UXor by Ibryamov (2015b). FHO 27 is located at about 9 from V521 Cyg.

3.2. V752 Cyg

The variability of V752 Cyg was reported in Erastova & Tsvetkov (1978). Kohoutek & Wehmeyer (1997) confirmed the variability of the star, measured its photographic magnitude =15.30 mag and registered H emission line in its spectrum. V752 Cyg is included in the list of YSO candidates published in Guieu et al. (2009).

The light curves of V752 Cyg from all our CCD observations (Poljančić Beljan et al. 2014; Ibryamov 2015a; and the present paper) are shown in Fig. 5. The symbols used for the different telescopes are as in Fig. 3. The results from our recent multicolour CCD observations of V752 Cyg are summarized in Table 5. The columns have the same contents as in Table 4.

Figure 5: CCD light curves of V752 Cyg for the period 2006 December–2015 September

It can be seen from Fig. 5 that during our study the brightness of V752 Cyg vary around some intermediate level. The star shows principally increases in the brightness with different amplitudes. The brightness of the star during the period of our observations 2006–2015 vary in the range 14.28–15.55 mag for -band, 14.89–16.67 mag for -band, 15.38–17.71 mag for -band, and 16.02–18.89 mag in -band. The observed amplitudes are =1.27 mag, =1.78 mag, =2.33 mag, and =2.87 mag.

The colour indices , , and versus magnitude during the period of our observations are plotted in Fig. 6. From the figure, it is seen that the star becomes bluer when it increases its brightness. Such colour variations are indication for flare events. These flares can be explained by increase in accretion rate from the circumstellar disk onto the stellar surface. Evidences of periodicity in the brightness variability are not detected. In the diagram (Fig. 2) V752 Cyg lies by 0.05 mag above the intrinsic T Tauri line – it have negligible infrared excess.

Figure 6: Relationship between magnitude and the , , and colour indices of V752 Cyg in the period 20062015

3.3. V1538 Cyg

The star V1538 Cyg was discovered and classified as a flare star by Erastova & Tsvetkov (1974). The authors reported a flare event on 1973 July 30 and determined its photographic magnitude =18.50 mag and =2.50 mag. Laugalys et al. (2006) registered H emission-line in the star’s spectrum and measured its magnitude =17.01 mag and colour index =4.32 mag. The authors determined the spectral type as M2 and the distance to the star as =248 pc.

The spectrum of V1538 Cyg taken on 2007 October 23 by Corbally et al. (2009) shows a M1 photosphere with low emission in H. In / diagram the star lies in the upper part of the early M dwarf band, so there are no indications of the presence of the envelope. This is confirmed by the fluxes – the energy distribution of the star no showed infrared radiation. According to Corbally et al. (2009) V1538 Cyg can be either an unreddened field dwarf with chromospheric activity, located at 350 pc, or a post-T Tauri star at the front edge of the NGC 7000/IC 5070 complex. Armond et al. (2011) included V1538 Cyg in the list of H emission-line star and measured its magnitudes as =16.28, =16.85 and =17.82 mag.

The multicolour light curves of V1538 Cyg from all our CCD observations in the period 2000–2015 (Poljančić Beljan et al. 2014; and the present paper) are shown in Fig. 7. The symbols used for the different telescopes are as in Fig. 3. The results of our recent multicolour CCD observations of the star are summarized in Table 6. The columns have the same contents as in Table 4.

Figure 7: CCD light curves of V1538 Cyg for the period 2000 June–2015 September

From Fig. 7 can be seen that during the period of our observations V1538 Cyg shows irregular variability in all bands, but significant flare events are not registered. The brightness of the star during the period 2000–2015 vary in the range 14.79–15.13 mag for -band, 15.78–16.26 mag for -band, 16.80–17.21 mag for -band, and 18.11–18.64 mag for -band. The observed amplitudes are =0.34 mag, =0.48 mag, =0.41 mag, and =0.53 mag in the same period.

Usually, such low amplitude variability is typical for low-mass WTTS, whose variability is produced by rotation of the spotted surface. This is confirmed by the position of the star in the 2MASS two-colour diagram in Fig. 2 – there are no indications of the presence of infrared excess. Evidences of periodicity in the brightness variability of V1538 Cyg are not detected.

3.4. V1539 Cyg

The star V1539 Cyg was discovered and classified as a H emission-line star by Herbig (1958) with photographic magnitude =17.00 mag. Welin (1973) confirmed it as a H emission star with strong H intensity and determined =15.50 and =17.00 mag.

Gieseking & Schumann (1976) discovered that star’s brightness vary with amplitude greater than 0.25 mag, which led to the conclusion of the suspected variability. Herbig & Bell (1988) classified V1539 Cyg as a T Tauri star with =16.30 mag. Kohoutek & Wehmeyer (1997) confirmed the variability of the star with maximum brightness in photoelectric system 14.50 mag. and determined its spectral type as K6IV.

The spectrum of V1539 Cyg taken on 2007 October 21 by Corbally et al. (2009) shows a G5e photosphere with strong emission in H. CaII and OI lines are also registered in emission. In / diagram the star lies by 0.12 mag above the intrinsic T Tauri line. The fluxes exhibit the presence of a considerable thermal emission from the dust envelope (Corbally et el. 2009). According to Findeisen et al. (2013) V1539 Cyg shows bursts events and they reported average stellar magnitude =14.60 mag and =0.70 mag.

The light curves of V1539 Cyg from all our CCD observations (Poljančić Beljan et al. 2014; Ibryamov 2015a; and the present paper) are shown in Fig. 8. The symbols used for the different telescopes are as in Fig. 3. The results of our recent multicolour CCD observations of the star are summarized in Table 7. The columns have the same contents as in Table 4.

Figure 8: CCD light curves of V1539 Cyg for the period 1997 June–2015 September

The brightness of V1539 Cyg during the period of our observations 1997–2015 vary in the range 13.34–13.68 mag for -band, 14.28–14.72 mag for -band, 15.28–15.79 mag for -band, and 16.56–17.26 mag for -band. The observed amplitudes are =0.34 mag, =0.44 mag, =0.51 mag, and =0.70 mag. From Fig. 8 it can be seen that during the period of our observations V1539 Cyg shows variability in all bands. This variability include short rises and decreases of the star’s brightness with small amplitudes.

Important result from our long-term photometric study of V1539 Cyg is that during the whole period of observations the total star’s brightness gradually decreases. Using a linear approximation for all our data of the star, we calculated the following values for the rates of decreases: 0.0117 mag for -band, 0.0119 mag for -band, 0.0109 mag for -band, and 0.0090 mag for -band.

The light curves of the star gives grounds to predict different reasons for observed variability of the star – existence of hot and cool spots on the stellar surface, and/or irregular obscuration of the star by circumstellar material. Evidences of periodicity in the brightness variability are not detected.

3.5. V1716 Cyg

The variability of V1716 Cyg was discovered by Erastova & Tsvetkov (1978). The authors reported irregular brightness fluctuations and measured its photographic magnitudes =17.00–17.50 mag (limit) and =16.10–17.50 mag (limit). Armond et al. (2011) included V1716 Cyg in the list of H emission-line star and measured its magnitudes as =15.95, =16.74 and =17.93 mag. Findeisen et al. (2013) discovered two bursts events of the star, which are separated by 35 days, as the first one lasting 5–20 days, and the second one – 3 days. The authors reported average stellar magnitude =16.50 mag and =1.10 mag.

Poljančić Beljan et al. (2014) determined the period of V1716 Cyg, which is found to be 4.15 days. This periodicity is probably connected with the stellar rotation and the position of the dark spots on the stellar surface.

The light curves of V1716 Cyg from all our CCD observations (Poljančić Beljan et al. 2014; Ibryamov 2015a; and the present paper) are shown in Fig. 9. The symbols used for the different telescopes are as in Fig. 3. The results of our recent multicolour CCD observations of the star are summarized in Table 8. The columns have the same contents as in Table 4.

Figure 9: CCD light curves of V1716 Cyg for the period 1997 June–2015 September

The brightness of V1716 Cyg during the period of our observations 1997–2015 vary in the range 14.43–15.36 mag for -band, 15.28–16.68 mag for -band, 16.14–17.93 mag for -band, and 17.05–19.50 mag for -band. The observed amplitudes are =0.93 mag, =1.40 mag, =1.79 mag, and =2.45 mag in the same period.

Ibryamov et al. (2015a) described four eruptive events of V1716 Cyg observed in all bands. The irregular flares can be explained with short-lived accretion-related events at the stellar surface or as flares from UV Cet-type. Other irregular variations of the star’s brightness, observed in Fig. 9 are with smaller amplitudes and are caused probably by rotating hot and cool spots on the stellar surface. These results are an indication that V1716 Cyg is likely CTTS.

In the / diagram (Fig. 2) the star lies by 0.11 mag above the intrinsic T Tauri line, i.e., it have infrared excess and this is indication of the presence of the envelope. Our new data confirm the periodicity of V1716 Cyg found by Poljančić Beljan et al. (2014).

3.6. V1957 Cyg

V1957 Cyg was discovered and classified as a flare star by Chavushian & Jankovics (1985). The authors reported a flare event on 1979 October 19 when the brightness of the star in -band increased from 18.00 to 16.00 mag. In the following series of observations performed in 1981 and 1984 flare events are not registered. Laugalys et al. (2006) classified V1957 Cyg as a K6 dwarf with possible H emission. The authors measured =16.30 mag and colour index =4.05 mag, and determined the distance to the star as =481 pc.

The spectrum of V1957 Cyg taken on 2007 October 22 by Corbally et al. (2009) shows a Ge photosphere with weak emission in H. The authors reported that in / diagram the star lies close to the intrinsic position of M0V star, but it can be a reddened G-type star, too. IRAC magnitudes measured by show no infrared excess. According to authors V1957 Cyg may have been in a particularly active phase at the time of photometric observations, and in quiet stage during the spectral observations.

The light curves of the star from all our CCD observations (Poljančić Beljan et al. 2014; and the present paper) are shown in Fig. 10. The symbols used for the different telescopes are as in Fig. 3. The results of our recent multicolour CCD observations of the star are summarized in Table 9. The columns have the same contents as in Table 4.

Figure 10: CCD light curves of V1957 Cyg for the period 2000 June–2015 September

The brightness of V1957 Cyg during the period 2000–2015 vary in the range 14.38–14.79 mag. for -band, 15.20–15.70 mag. for -band, 16.06–16.54 mag. for -band, and 17.25–17.83 mag. for -band. The observed amplitudes are =0.41 mag, =0.50 mag, =0.48 mag, and =0.58 mag during the same period.

It can be seen from Fig. 10 that the star’s brightness increasing smoothly to the mid-2010, then it begins decrease smoothly to the mid-2014. From the mid-2014 so far the star’s brightness vary around some intermediate level with very small amplitudes. From the observed amplitudes of V1957 Cyg and its position in the two-colour diagram (Figure 2) it can be assumed that the star is probably M dwarf with chromospheric activity. Evidences of periodicity in the brightness variability of the star are not detected.

3.7. V2051 Cyg

V2051 Cyg was discovered and classified as a flare star by Parsamian et al. (1994). The authors reported a flare event on 1977 September 07 when the brightness of the star in -band increased from the plate limit to 14.00 mag with amplitude >4.00 mag.

Laugalys et al. (2006) classified V2051 Cyg as a possible T Tauri star with =16.59 mag. The spectrum of the star taken on 2007 October 21 by Corbally et al. (2009) shows a M3.5e photosphere with weak emission in H. In / diagram the star lies close to the intrinsic position of M3V stars with no infrared excess. Its energy distribution, constructed from the 2MASS and observations, also suggest for a normal star without envelope. According to Corbally et al. (2009) V2051 Cyg is most probably a M dwarf with weak chromospheric activity and the distance to the star is =137 pc, i.e., the star cannot have any relation to the NGC 7000/IC 5070 complex.

Poljančić Beljan et al. (2014) determined the period of the star, which is found to be 384 days, likely caused by precession of the circumstellar disk or by clouds of gas and dust orbiting the star.

The multicolour light curves of V2051 Cyg from all our CCD observations in the period 2000–2015 (Poljančić Beljan et al. 2014; Ibryamov 2015a; and the present paper) are shown in Fig 11. The symbols used for the different telescopes are as in Fig 3. The results of our recent multicolour CCD observations of the star are summarized in Table 10. The columns have the same contents as in Table 4.

Figure 11: CCD light curves of V2051 Cyg for the period 2000 June–2015 September

During the period of our observations flare events are not registered, except a few low amplitude increases in brightness in - and -band. The brightness of the star during the period 2000–2015 vary in the range 13.84–14.02 mag for -band, 15.40–15.68 mag for -band, 16.40–16.77 mag for -band, and 17.80–18.35 mag for -band. The observed amplitudes are =0.18 mag, =0.28 mag, =0.37 mag, and =0.55 mag in the same period. Low amplitude of variability and relatively stable light variations confirm the assumptions on the nature of V2051 Cyg as a M dwarf with weak chromospheric activity (Corbally et al. 2009).

3.8. LkH 186

The star LkH 186 was discovered and classified as a H emission-line star by Herbig (1958) with photographic magnitude =18.00 mag. Herbig & Bell (1988) classified it as a T Tauri variable with spectral type K5. Cohen & Kuhi (1979) measured =18.00 mag of the star. In the paper of Weintraub (1990) LkH 186 is also classified as a T Tauri variable.

Guieu et al. (2009) included the star in their list of YSO candidates and measured =14.747, =17.395, and =19.322 mag. Armond et al. (2011) included it in the list of H emission-line star and measured =15.85, =16.68 and =18.12 mag and classified it as a CTTS.

The light curves of LkH 186 from all our CCD observations (Poljančić Beljan et al. 2014; and the present paper) are shown in Fig. 12. The symbols used for the different telescopes are as in Fig. 3. The results of our recent multicolour CCD observations of the star are summarized in Table 11. The columns have the same contents as in Table 4.

Figure 12: CCD light curves of LkH 186 for the period 1997 June–2015 September

The brightness of the star during the period 1997–2015 vary in the range 14.39–14.82 mag for -band, 15.65–16.42 mag for -band, 16.91–17.68 mag for -band, and 18.37–19.50 mag for -band. The observed amplitudes are =0.43 mag, =0.77 mag, =0.77 mag, and =1.13 mag.

It can be seen from Fig. 12 that the star usually spends most of the time at low light. LkH 186 exhibit increases of the brightness with different amplitudes probably due to the presence of hot spots on the stellar surface. The variability is produced by variable accretion from the circumstellar disk and it is typical of CTTS.

In the two-colour diagram (Fig. 2) the star lies by 0.37 mag above the intrinsic T Tauri line. The star have clear infrared excess, indicating the presence of a circumstellar disk. Evidences of periodicity in the brightness variability are not detected.

3.9. LkH 187

The star LkH 187 was discovered and classified as a H emission-line star by Herbig (1958) with photographic magnitude =18.50. Herbig & Bell (1988) classified it as a T Tauri variable with spectral type K3. Cohen & Kuhi (1979) measured =18.10 mag of the star. In the work of Weintraub (1990) LkH 187 is also classified as a T Tauri variable.

Guieu et al. (2009) included the star in their list of YSO candidates and measured =14.811, =17.639, and =19.476 mag. Armond et al. (2011) included it in the list of H emission-line star and measured =16.00, =17.05 and =18.56 mag and classified it as a CTTS.

The light curves of LkH 187 from all our CCD observations (Poljančić Beljan et al. 2014; and the present paper) are shown in Fig. 13. The symbols used for the different telescopes are as in Fig. 3. The results of our recent multicolour CCD observations of the star are summarized in Table 12. The columns have the same contents as in Table 4.

Figure 13: CCD light curves of LkH 187 for the period 1997 June–2015 September

The brightness of the star during the period 1997–2015 vary in the range 14.46–15.02 mag for -band, 15.68–16.71 mag for -band, 17.02–18.15 mag for -band, and 18.66–19.85 mag for -band. The observed amplitudes are =0.56 mag, =1.03 mag, =1.13 mag, and =1.19 mag.

It can be seen from Fig. 13 that similar to LkH 186, LkH 187 usually spends most of the time at low light. The star exhibit increases of the brightness with different amplitudes. This variability is due likely to the presence of hot spots on the stellar surface, i.e., it is produced by strong variable accretion from the circumstellar disk.

LkH 187 shows variability typical of CTTS. In the 2MASS two-colour diagram (Fig. 2) the star lies by 0.38 mag above the intrinsic T Tauri line. LkH 187 have clear infrared excess, indicating the presence of a circumstellar disk. Evidences of periodicity in the brightness variability are not detected.

3.10. LkH 189

The star LkH 189 was discovered and classified as a H emission-line star by Herbig (1958) with photographic magnitude =17.50. Welin (1973) confirmed it as an H emission-line star. Herbig & Bell (1988) classified it as a T Tauri variable with spectral type K6 and photographic magnitude 17.00 mag. Cohen & Kuhi (1979) measured =17.00 mag of the star. In the paper of Weintraub (1990) LkH 189 is also classified as a T Tauri variable.

Laugalys et al. (2006) classified LkH 189 as a T Tauri star with =16.69 mag and photographic spectral type K6. The position of the star in the two-colour / diagram obtained by the Laugalys et al. (2006) and Meyer et al. (1997) suggest increased disk thickness and interstellar reddening. Guieu et al. (2009) included the star in their list of YSO candidates and measured =13.936, =16.376, and =18.175 mag. Armond et al. (2011) included it in the list of H emission-line star and measured =15.03, =15.80 and =17.10 mag and classified it as a CTTS.

The light curves of LkH 189 from all our CCD observations (Poljančić Beljan et al. 2014; and the present paper) are shown in Fig. 14. The symbols used for the different telescopes are as in Fig. 3. The results of our recent multicolour CCD observations of the star are summarized in Table 13. The columns have the same contents as in Table 4.

Figure 14: CCD light curves of LkH 189 for the period 1997 June–2015 September

The brightness of LkH 189 during the period 1997–2015 vary in the range 13.76–14.30 mag for -band, 14.99–15.76 mag for -band, 16.25–17.06 mag for -band, and 17.69–18.75 mag for -band. The observed amplitudes are =0.54 mag, =0.77 mag, =0.81 mag, and =1.06 mag in the same period.

During our study the brightness of LkH 189 vary around some intermediate level (Fig. 14). Both increases and drops in the brightness with different amplitudes are observed. The observed drops of the star’s brightness likely are caused by the existence of cool spots or groups of spots on the stellar surface or by irregular obscuration of the star by circumstellar material. The observed increases of the star’s brightness probably are caused by the existence of hot spots on the stellar surface.

We carried out a periodicity search using our data from 2010 May to 2015 September with persea Version 2.6 (written by G. Maciejewski on the technique, Schwarzenberg-Cherny (1996)) and with period04 (Lenz & Breger 2005) softwares. Our time-series analysis of the data indices a 2.450980 0.029612 days period and led to the ephemeris:

(1)

False Alarm Probability estimation was done by randomly deleting about 10%-15% of the data for about 30 times and then retuning the period of determination. The period and starting age () determination remain stable, even with a subsample with 30% of the data removed. Fig. 15 exhibits the -band folded light curve of LkH 189 according to the ephemeris (1). Data obtained in -bands show the same shape on periodicity. The found period is stable during time interval of several years and it is typical rotational period of young low-mass star. The periodicity could be caused by rotation modulation of the dark spots on the stellar surface.

Figure 15: -band folded curve of LkH 189

3.11. LkH 191

The star LkH 191 was discovered and classified as a H emission-line star by Herbig (1958) with photographic magnitude =14.00. Herbig & Bell (1988) classified it as a T Tauri variable with photographic magnitude 12.08 and spectral type K0. Terranegra et al. (1994) classified LkH 191 as CTTS with =12.95 mag and determined its photometric spectral type as K0V. Fernandez & Eiroa (1996) presented the light curve in -band of the star for the period 1988 July–1991 August. The light curve show approximately constant brightness (with variations in -band from 12.89 to 12.99 mag).

Laugalys et al. (2006) measured =13.06 mag, colour index =3.506 mag and photometric spectral type K6e. Authors noticed the absence of a strong H emission and presence of a small dust emission suggested no significant deviation of the star from the main sequence. The position of LkH 191 in two-colour / diagram is slightly below intrinsic T Tauri line. According to Laugalys et al. (2006) LkH 191 has probably lost its envelope during the past 50 years.

Grankin et al. (2007) conducted long-term study of LkH 191 during the period 1986 July–1995 August. The authors reported that the star’s brightness in vary from 12.87 to 13.09 mag. Artemenko et al. (2012) determined the period of the star, which is found to be 2.08 days.

The light curves of LkH 191 from all our CCD observations (Poljančić Beljan et al. 2014; and the present paper) are shown in Fig. 16. The symbols used for the different telescopes are as in Fig. 3. The results of our recent multicolour CCD observations of the star are summarized in Table 14. The columns have the same contents as in Table 4.

Figure 16: CCD light curves of LkH 191 for the period 2000 October–2015 September

The brightness of LkH 191 during the period 2000–2015 vary in the range 11.48–11.66 mag for -band, 12.07–12.33 mag for -band, 12.74–12.99 mag for -band, and 13.87–14.23 mag for -band. The observed amplitudes are =0.18 mag, =0.26 mag, =0.25 mag, and =0.36 mag.

It can be seen from Fig. 16 that LkH 191 not shows some significant photometric activity. Our data agree with the hypothesis of an CTTS star, but LkH 191 may also be post-T Tauri star. We carried out a periodicity search using our data, but we could not confirm the findings of Artemenko et al. (2012).

3.12. [Kw97] 53-11

The star [KW97] 53-11 was mentioned in the catalog of Kohoutek & Wehmeyer (1997, 1999) with brightness in the photovisual system =17.20 mag. Cohen & Kuhi (1979) reported =17.70 mag of the star and determined its spectral type as M2. Armond et al. (2011) report a lack of H emission from this star.

The light curves of [KW97] 53-11 from all our CCD observations (Poljančić Beljan et al. 2014; and the present paper) are shown in Fig. 17. The symbols used for the different telescopes are as in Fig. 3. The results of our recent multicolour CCD observations of the star are summarized in Table 15. The columns have the same contents as in Table 4.

Figure 17: CCD light curves of [KW97] 53-11 for the period 1997 June–2015 September

The brightness of the star during the period 2000–2015 vary in the range 15.81–16.44 mag for -band and 18.32–19.04 mag for -band. The observed amplitudes are =0.63 mag and =0.72 mag in the same period. The magnitudes of the star in and -band are below the limit of telescopes used.

It can be seen from Fig. 17 that during our study the brightness of [KW97] 53-11 vary around some intermediate level. The star shows both increases in the brightness with different amplitudes and short fading events in the brightness. Probably the observed fading events are caused by the existence of cool spots or group of spots, and the observed increases of the star’s brightness likely are caused by the existence of hot spots on the stellar surface. Evidences of periodicity in the brightness variability of [KW97] 53-11 are not detected.

3.13. [Kw97] 53-23

The star [KW97] 53-23 was mentioned in the catalog of Kohoutek & Wehmeyer (1997, 1999) with only equatorial coordinates and finding charts available. Guieu et al. (2009) included the star in their list of YSO candidates and measured its magnitudes =15.093, =18.445, and =20.649 mag.

The light curves of [KW97] 53-23 from all our CCD observations (Poljančić Beljan et al. 2014; and the present paper) are shown in Fig. 18. The symbols used for the different telescopes are as in Fig. 3. The results of our recent multicolour CCD observations of the star are summarized in Table 16. The columns have the same contents as in Table 4.

Figure 18: CCD light curves of [KW97] 53-23 for the period 1997 June–2015 September

It can be seen from Fig. 18 that [KW97] 53-23 shows both increases and drops in the brightness with different amplitudes. The brightness of the star during the period 1997–2015 vary in the range 14.74–15.34 mag for -band, 16.28–17.73 mag for -band, 18.01–19.49 mag for -band, and 19.92–20.49 mag for -band. The observed amplitudes are =0.60 mag, =1.45 mag, =1.48 mag, and 0.57 mag.

The deepest drop in the brightness of [KW97] 53-23 is observed during 2014. Due to the limit of our photometric data during the minimal brightness some magnitudes in - and especially in -band are not registered. We have only some -band photometric data of the star collected with the 2-m RCC and the 1.3-m RC telescopes.

The observed increases in the brightness of [KW97] 53-23 are caused probably by the existence of hot spots on the stellar surface, typical of CTTS. The observed drops in the brightness are caused probably by the existence of cool spots on the stellar surface or by irregular obscuration of the star by circumstellar material.

On Fig. 19, the colour indices and versus magnitude during the period of our observations are plotted. The diagrams (especially ) shows evidences for bluing effect and probably the observed deepest drop in brightness are caused by obscuration of the star from circumstellar material.

Figure 19: Relationship between magnitude and the and colour indices of [KW97] 53-23 in the period 19972015

In the two-colour diagram (Fig. 2) [KW97] 53-23 lies by 0.48 mag above the intrinsic T Tauri line. Therefore, the star have clear infrared excess, indicating the presence of a circumstellar disk. Evidences of periodicity in the brightness variability of the star are not detected.

3.14. [Kw97] 53-36

The star [KW97] 53-36 was mentioned in the catalog of Kohoutek & Wehmeyer (1997, 1999) with it’s brightness in the photographic system =12.70 mag.

The light curves of [KW97] 53-36 from all our CCD observations (Poljančić Beljan et al. 2014; and the present paper) are shown in Fig. 20. The symbols used for the different telescopes are as in Fig. 3. The results of our recent multicolour CCD observations of the star are summarized in Table 17. The columns have the same contents as in Table 4.

Figure 20: CCD light curves of [KW97] 53-36 for the period 2006 December–2015 September

It can be seen from Fig. 20 that [KW97] 53-36 not shows some significant photometric activity. The brightness of the star during the period 2006–2015 vary in the range 11.53–11.67 mag for -band, 11.84–11.96 mag for -band, 12.17–12.38 mag for -band, and 12.98–13.17 mag for -band. The observed amplitudes are =0.14 mag, =0.12 mag, =0.21 mag, and =0.19 mag in the same period.

In the two-colour diagram (Fig. 2) the star lies close to the intrinsic position of G0 stars with no infrared excess, i.e., there are no indications of the presence of a circumstellar disk. Most probably the star is a G giant with weak chromospheric activity. Evidences of periodicity in the brightness variability are not detected.

4. Conclusion

We presented the light curves of 14 PMS stars located in NGC 7000/IC 5070 star-forming complex. Our results complement the previously rare insights into their photometry. Seven of studied stars (V752 Cyg, V1539 Cyg, V1716 Cyg, LkH 186, LkH 187, LkH 191, [KW97] 53-23) shows characteristics for CTTS, one star (V1538 Cyg) probably is WTTS, for three objects (V1539 Cyg, LkH 189, [KW97] 53-11) we waver between CTTS and WTTS, for their exact classification are necessary spectral observations, three stars (V1957 Cyg, V2051 Cyg, [KW97] 53-36) likely are evolved PMS stars, and one stars (V521 Cyg) from our study we found indications of UXor variability. For one investigated star, LkH 189, we found periodicity – 2.45-day period.

We are continuing to collect photometric observations of the field of ’Gulf of Mexico’. Further regular observations of the PMS stars in the same field will be of a great importance for their exact classification and are encouraging.

Acknowledgements

This research has made use of the NASA’s Astrophysics Data System Abstract Service, the SIMBAD database and the VizieR catalogue access tool, operated at CDS, Strasbourg, France. This publication makes use of data products from the Two Micron All Sky Survey, which is a joint project of the University of Massachusetts and the Infrared Processing and Analysis Center/California Institute of Technology, funded by the National Aeronautics and Space Administration and the National Science Foundation. The authors thank the Director of Skinakas Observatory Prof. I. Papamastorakis and Prof. I. Papadakis for the award of telescope time.

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Appendix A ONLINE MATERIAL. Photometric CCD observations and data of the stars from our study

Date J.D. (24…) I R V B Tel CCD
03.08.2014 56873.386 12.25 13.13 14.02 15.35 Sch FLI
04.08.2014 56874.407 12.27 13.11 13.97 15.33 Sch FLI
18.08.2014 56888.450 12.09 12.93 13.77 14.99 Sch FLI
19.08.2014 56889.365 12.04 12.85 13.68 14.93 Sch FLI
29.08.2014 56899.303 11.93 12.74 13.55 14.77 1.3-m ANDOR
26.11.2014 56988.181 11.95 12.74 13.53 14.74 Sch FLI
13.12.2014 57005.181 11.91 12.71 13.50 14.69 Sch FLI
14.12.2014 57006.220 11.94 12.73 13.51 - Sch FLI
24.12.2014 57016.174 12.05 12.87 13.74 15.01 2-m VA
25.12.2014 57017.175 12.08 12.90 13.75 15.03 2-m VA
21.02.2015 57074.641 12.31 13.22 14.10 15.50 Sch FLI
23.04.2015 57136.487 12.08 12.92 13.72 15.00 Sch FLI
25.04.2015 57138.491 12.14 13.01 13.85 15.14 Sch FLI
18.05.2015 57161.423 12.02 12.83 13.64 14.87 Sch FLI
19.05.2015 57162.460 11.98 12.77 13.57 14.80 Sch FLI
21.05.2015 57164.459 12.02 12.84 13.62 14.89 Sch FLI
24.05.2015 57167.409 12.02 12.81 13.65 14.87 2-m VA
12.06.2015 57186.444 11.98 12.79 13.56 14.81 Sch FLI
13.06.2015 57187.478 12.06 12.85 13.68 14.90 2-m VA
16.06.2015 57190.367 12.08 12.86 13.70 14.96 2-m VA
16.07.2015 57220.364 12.09 12.93 13.75 15.01 Sch FLI
17.07.2015 57221.417 12.05 12.88 13.70 14.96 Sch FLI
19.07.2015 57223.400 12.09 12.87 13.77 14.99 2-m VA
20.07.2015 57224.422 12.06 12.85 13.70 14.95 2-m VA
11.08.2015 57246.355 11.88 12.66 13.46 14.65 1.3-m ANDOR
12.08.2015 57247.394 11.84 12.63 13.41 14.60 1.3-m ANDOR
17.08.2015 57252.384 11.89 12.65 13.45 14.65 2-m VA
24.08.2015 57259.337 11.89 12.69 13.43 14.65 Sch FLI
25.08.2015 57260.342 11.88 12.67 13.43 14.63 Sch FLI
03.09.2015 57269.328 11.90 12.69 13.44 14.69 Sch FLI
04.09.2015 57270.330 11.93 12.69 13.52 14.71 2-m VA
05.09.2015 57271.323 11.94 12.69 13.51 14.70 2-m VA
06.09.2015 57272.288 11.94 12.71 13.56 14.72 2-m VA
Table 4: Continued.
Date J.D. (24…) I R V B Tel CCD
03.08.2014 56873.386 15.10 16.37 17.43 18.36 Sch FLI
04.08.2014 56874.407 14.96 15.76 16.36 16.96 Sch FLI
18.08.2014 56888.450 15.11 15.98 16.60 17.30 Sch FLI
19.08.2014 56889.365 15.21 16.33 17.20 18.19 Sch FLI
26.11.2014 56988.181 15.07 16.06 16.70 17.62 Sch FLI
13.12.2014 57005.181 14.97 16.10 16.87 17.91 Sch FLI
14.12.2014 57006.220 15.21 16.43 17.16 - Sch FLI
21.02.2015 57074.641 15.25 16.28 16.90 17.97 Sch FLI
23.04.2015 57136.487 15.21 16.60 17.47 18.77 Sch FLI
19.05.2015 57162.460 15.29 16.57 17.27 18.75 Sch FLI
12.06.2015 57186.444 14.96 15.89 16.50 17.39 Sch FLI
16.07.2015 57220.364 14.88 15.84 16.60 17.47 Sch FLI
17.07.2015 57221.417 14.97 15.96 16.68 17.50 Sch FLI
24.08.2015 57259.337 14.93 15.78 16.22 17.06 Sch FLI
25.08.2015 57260.342 15.30 16.30 16.91 17.95 Sch FLI
03.09.2015 57269.328 15.03 16.11 16.71 17.79 Sch FLI
Table 5: Continued.
Date J.D. (24…) I R V B Tel CCD
15.05.2013 56428.404 15.04 15.93 17.04 18.14 60-cm FLI
10.04.2013 56392.510 15.03 16.12 17.11 18.44 Sch FLI
11.04.2013 56394.482 15.00 15.99 16.94 18.40 Sch FLI
02.05.2013 56415.418 14.97 16.03 16.95 18.43 Sch FLI
17.05.2013 56430.408 15.00 15.95 16.96 - 60-cm FLI
19.05.2013 56432.405 14.98 15.99 16.81 - 60-cm FLI
30.05.2013 56443.367 14.96 16.00 16.97 18.50 Sch FLI
31.05.2013 56444.354 14.96 15.98 16.97 18.45 Sch FLI
04.08.2013 56509.288 15.00 16.06 17.05 18.47 Sch FLI
05.08.2013 56510.369 15.04 16.02 16.96 18.19 60-cm FLI
05.08.2013 56510.386 14.97 16.05 17.00 18.35 Sch FLI
06.08.2013 56511.411 14.99 16.04 17.00 18.41 Sch FLI
06.08.2013 56511.413 15.05 16.11 16.95 18.11 60-cm FLI
07.08.2013 56512.398 14.99 16.04 16.98 18.35 Sch FLI
07.08.2013 56512.403 15.06 16.01 17.02 18.10 60-cm FLI
08.08.2013 56513.382 15.02 16.06 16.99 18.37 60-cm FLI
09.08.2013 56514.350 15.02 15.96 17.00 18.41 60-cm FLI
12.08.2013 56517.284 15.01 15.98 16.72 18.54 60-cm FLI
04.09.2013 56540.274 14.96 16.00 16.97 18.36 Sch FLI
05.09.2013 56541.322 14.96 15.99 16.94 18.27 Sch FLI
06.09.2013 56542.381 15.00 16.09 17.00 18.40 Sch FLI
11.09.2013 56547.383 15.07 16.03 16.98 18.21 60-cm FLI
14.09.2013 56550.363 15.00 15.97 16.94 18.15 60-cm FLI
17.09.2013 56553.282 14.94 15.99 16.97 18.37 1.3-m ANDOR
11.10.2013 56577.306 15.02 15.98 16.98 18.23 60-cm FLI
12.10.2013 56578.331 15.08 16.03 17.03 18.44 60-cm FLI
07.11.2013 56604.264 15.02 16.08 17.06 18.46 60-cm FLI
28.12.2013 56655.200 14.98 16.04 16.99 18.31 Sch FLI
29.12.2013 56656.180 14.95 16.04 17.00 18.31 Sch FLI
30.12.2013 56657.193 15.01 16.05 16.98 18.33 Sch FLI
23.01.2014 56681.189 14.96 16.01 17.01 18.31 Sch FLI
22.03.2014 56738.590 14.98 16.05 16.97 18.33 Sch FLI
21.05.2014 56799.425 14.97 15.99 16.99 18.49 Sch FLI
28.06.2014 56837.417 14.99 16.05 17.02 18.51 Sch FLI
29.06.2014 56838.398 14.99 16.07 17.07 18.36 Sch FLI
20.07.2014 56859.390 14.97 15.97 16.95 18.46 60-cm FLI
21.07.2014 56860.391 15.02 16.06 17.11 - 60-cm FLI
24.07.2014 56863.339 15.03 16.11 - 18.40 Sch FLI
25.07.2014 56864.356 15.02 15.94 - - Sch FLI
03.08.2014 56873.386 14.99 16.11 17.09 18.51 Sch FLI
04.08.2014 56874.407 15.01 16.14 17.15 18.58 Sch FLI
18.08.2014 56888.450 14.98 16.04 16.99 18.39 Sch FLI
19.08.2014 56889.365 14.96 16.04 16.99 18.35 Sch FLI
29.08.2014 56899.303 14.99 16.06 16.98 18.36 1.3-m ANDOR
26.11.2014 56988.181 14.98 16.02 16.95 18.45 Sch FLI
13.12.2014 57005.181 14.98 16.10 17.06 18.41 Sch FLI
14.12.2014 57006.220 14.98 16.04 16.93 - Sch FLI
21.02.2015 57074.641 14.96 15.96 16.98 18.35 Sch FLI
23.04.2015 57136.487 14.94 15.96 16.88 18.20 Sch FLI
25.04.2015 57138.491 14.95 16.00 16.90 18.40 Sch FLI
18.05.2015 57161.423 14.94 15.95 16.87 18.53 Sch FLI
19.05.2015 57162.460 14.94 15.99 16.91 18.41 Sch FLI
21.05.2015 57164.459 14.95 15.98 16.87 18.23 Sch FLI
12.06.2015 57186.444 14.95 15.99 16.88 18.24 Sch FLI
16.07.2015 57220.364 14.94 15.96 16.92 18.26 Sch FLI
17.07.2015 57221.417 14.94 15.99 16.92 18.24 Sch FLI
11.08.2015 57246.355 14.92 15.96 16.91 18.34 1.3-m ANDOR
12.08.2015 57247.394 13.96 15.99 16.94 18.37 1.3-m ANDOR
24.08.2015 57259.337 14.97 15.99 16.90 18.32 Sch FLI
25.08.2015 57260.342 14.95 16.03 16.89 18.33 Sch FLI
03.09.2015 57269.328 14.96 15.95 16.86 18.23 Sch FLI
Table 6: Continued.
Date J.D. (24…) I R V B Tel CCD
03.08.2014 56873.386 13.57 14.59 15.65 17.01 Sch FLI
04.08.2014 56874.407 13.49 14.47 15.52 16.85 Sch FLI
18.08.2014 56888.450 13.61 14.66 15.74 17.13 Sch FLI
19.08.2014 56889.365 13.60 14.62 15.71 17.14 Sch FLI
29.08.2014 56899.303 13.58 14.61 15.66 17.04 1.3-m ANDOR
26.11.2014 56988.181 13.61 14.66 15.72 17.13 Sch FLI
13.12.2014 57005.181 13.54 14.57 15.54 16.98 Sch FLI
14.12.2014 57006.220 13.60 14.65 15.62 - Sch FLI
21.02.2015 57074.641 13.59 14.58 15.54 16.85 Sch FLI
23.04.2015 57136.487 13.53 14.54 15.58 16.97 Sch FLI
25.04.2015 57138.491 13.60 14.64 15.68 17.03 Sch FLI
18.05.2015 57161.423 13.62 14.67 15.72 17.05 Sch FLI
19.05.2015 57162.460 13.54 14.54 15.54 16.89 Sch FLI
21.05.2015 57164.459 13.58 14.63 15.67 17.07 Sch FLI
12.06.2015 57186.444 13.52 14.56 15.52 16.90 Sch FLI
16.07.2015 57220.364 13.57 14.62 15.69 17.08 Sch FLI
17.07.2015 57221.417 13.62 14.67 15.72 17.09 Sch FLI
11.08.2015 57246.355 13.53 14.60 15.68 17.08 1.3-m ANDOR
12.08.2015 57247.394 13.58 14.63 15.68 17.08 1.3-m ANDOR
24.08.2015 57259.337 13.60 14.64 15.67 17.04 Sch FLI
25.08.2015 57260.342 13.58 14.63 15.62 17.09 Sch FLI
03.09.2015 57269.328 13.52 14.56 15.53 16.94 Sch FLI
Table 7: Continued.
Date J.D. (24…) I R V B Tel CCD
03.08.2014 56873.386 15.09 16.48 17.67 19.29 Sch FLI
04.08.2014 56874.407 15.07 16.58 17.66 - Sch FLI
18.08.2014 56888.450 15.14 16.59 17.82 - Sch FLI
19.08.2014 56889.365 15.15 16.64 17.77 19.25 Sch FLI
29.08.2014 56899.303 14.99 16.41 17.59 19.21 1.3-m ANDOR
26.11.2014 56988.181 15.15 16.64 17.75 19.45 Sch FLI
13.12.2014 57005.181 15.09 16.64 17.64 - Sch FLI
14.12.2014 57006.220 15.09 16.52 17.59 - Sch FLI
24.12.2014 57016.174 14.99 16.24 17.49 19.18 2-m VA
25.12.2014 57017.175 15.10 16.42 17.67 19.35 2-m VA
21.02.2015 57074.641 15.14 16.58 17.64 - Sch FLI
23.04.2015 57136.487 15.02 16.40 17.49 19.15 Sch FLI
25.04.2015 57138.491 15.08 16.52 17.61 19.07 Sch FLI
18.05.2015 57161.423 15.03 16.42 17.66 - Sch FLI
19.05.2015 57162.460 15.15 16.61 17.56 19.20 Sch FLI
21.05.2015 57164.459 15.05 16.44 17.53 19.32 Sch FLI
24.05.2015 57167.409 15.04 16.24 17.57 19.42 2-m VA
12.06.2015 57186.444 15.04 16.50 17.61 19.32 Sch FLI
13.06.2015 57187.478 15.03 16.24 17.59 19.22 2-m VA
16.06.2015 57190.367 14.93 16.15 17.45 19.14 2-m VA
16.07.2015 57220.364 15.16 16.54 17.68 19.26 Sch FLI
17.07.2015 57221.417 15.08 16.50 17.63 19.15 Sch FLI
19.07.2015 57223.400 14.98 16.21 17.51 19.17 2-m VA
20.07.2015 57224.422 15.05 16.29 17.61 19.29 2-m VA
11.08.2015 57246.355 15.06 16.47 17.63 19.24 1.3-m ANDOR
12.08.2015 57247.394 15.01 16.42 17.57 19.14 1.3-m ANDOR
17.08.2015 57252.384 14.99 16.21 17.50 19.16 2-m VA
24.08.2015 57259.337 15.05 16.49 17.45 - Sch FLI
25.08.2015 57260.342 15.02 16.39 17.49 18.92 Sch FLI
03.09.2015 57269.328 15.09 16.46 17.59 19.22 Sch FLI
04.09.2015 57270.330 15.05 16.33 17.63 19.29 2-m VA
05.09.2015 57271.323 15.06 16.26 17.54 19.22 2-m VA
06.09.2015 57272.288 15.00 16.18 17.44 19.08 2-m VA
Table 8: Continued.
Date J.D. (24…) I R V B Tel CCD
15.05.2013 56428.404 14.65 15.41 16.31 17.52 60-cm FLI
10.04.2013 56392.510 14.57 15.45 16.32 - Sch FLI
11.04.2013 56394.482 14.63 15.47 16.33 17.55 Sch FLI
02.05.2013 56415.418 14.63 15.47 16.33 17.60 Sch FLI
17.05.2013 56430.408 14.65 15.52 16.29 - 60-cm FLI
19.05.2013 56432.405 14.62 15.40 16.26 17.39 60-cm FLI
30.05.2013 56443.367 14.57 15.44 16.30 17.50 Sch FLI
31.05.2013 56444.354 11.57 15.43 16.26 17.47 Sch FLI
04.08.2013 56509.288 14.65 15.62 16.47 17.80 Sch FLI
05.08.2013 56510.369 14.69 15.59 16.40 17.54 60-cm FLI
05.08.2013 56510.386 14.64 15.55 16.41 17.67 Sch FLI
06.08.2013 56511.411 14.59 15.49 16.32 17.62 Sch FLI
06.08.2013 56511.413 14.66 15.41 16.33 17.50 60-cm FLI
07.08.2013 56512.398 14.58 15.46 16.29 17.55 Sch FLI
07.08.2013 56512.403 14.65 15.41 16.25 17.56 60-cm FLI
08.08.2013 56513.382 14.63 15.54 16.23 17.55 60-cm FLI
09.08.2013 56514.350 14.70 15.59 16.40 17.52 60-cm FLI
12.08.2013 56517.284 14.55 15.41 16.28 17.72 60-cm FLI
04.09.2013 56540.274 14.63 15.54 16.39 17.66 Sch FLI
05.09.2013 56541.322 14.68 15.63 16.48 17.71 Sch FLI
06.09.2013 56542.381 14.64 15.57 16.44 17.66 Sch FLI
11.09.2013 56547.383 14.72 15.59 16.47 17.69 60-cm FLI
14.09.2013 56550.363 14.68 15.50 16.38 17.66 60-cm FLI
17.09.2013 56553.282 14.58 15.51 16.36 17.56 1.3-m ANDOR
11.10.2013 56577.306 14.66 15.58 16.37 17.58 60-cm FLI
12.10.2013 56578.331 14.73 15.56 16.43 17.70 60-cm FLI
07.11.2013 56604.264 14.79 15.64 16.51 17.82 60-cm FLI
28.12.2013 56655.200 14.60 15.49 16.36 17.52 Sch FLI
29.12.2013 56656.180 14.66 15.60 16.44 17.68 Sch FLI
30.12.2013 56657.193 14.67 15.60 16.49 17.81 Sch FLI
23.01.2014 56681.189 14.60 15.48 16.33 17.60 Sch FLI
22.03.2014 56738.590 14.63 15.52 16.35 17.54 Sch FLI
21.05.2014 56799.425 14.67 15.60 16.43 17.73 Sch FLI
28.06.2014 56837.417 14.63 15.49 16.39 17.69 Sch FLI
29.06.2014 56838.398 14.61 15.55 16.37 17.61 Sch FLI
20.07.2014 56859.390 14.68 15.50 16.30 - 60-cm FLI
21.07.2014 56860.391 14.70 15.56 16.32 - 60-cm FLI
24.07.2014 56863.339 14.65 15.58 - 17.67 Sch FLI
25.07.2014 56864.356 14.62 15.55 - - Sch FLI
03.08.2014 56873.386 14.66 15.60 16.45 17.68 Sch FLI
04.08.2014 56874.407 14.66 15.58 16.42 17.69 Sch FLI
18.08.2014 56888.450 14.68 15.68 16.54 17.76 Sch FLI
19.08.2014 56889.365 14.66 15.61 16.46 17.68 Sch FLI
29.08.2014 56899.303 14.69 15.64 16.49 17.75 1.3-m ANDOR
26.11.2014 56988.181 14.74 15.70 16.54 17.83 Sch FLI
13.12.2014 57005.181 14.65 15.59 16.40 17.72 Sch FLI
14.12.2014 57006.220 14.69 15.62 16.36 - Sch FLI
21.02.2015 57074.641 14.69 15.60 16.40 17.67 Sch FLI
23.04.2015 57136.487 14.64 15.61 16.41 17.70 Sch FLI
25.04.2015 57138.491 14.67 15.60 16.40 17.73 Sch FLI
18.05.2015 57161.423 14.70 15.63 16.48 17.82 Sch FLI
19.05.2015 57162.460 14.71 15.66 16.48 17.80 Sch FLI
21.05.2015 57164.459 14.67 15.60 16.41 17.62 Sch FLI
12.06.2015 57186.444 14.66 15.60 16.39 17.71 Sch FLI
16.07.2015 57220.364 14.70 15.64 16.46 17.68 Sch FLI
17.07.2015 57221.417 14.68 15.60 16.45 17.75 Sch FLI
11.08.2015 57246.355 14.67 15.62 16.47 17.75 1.3-m ANDOR
12.08.2015 57247.394 14.65 15.58 16.43 17.72 1.3-m ANDOR
24.08.2015 57259.337 14.66 15.57 16.40 17.70 Sch FLI
25.08.2015 57260.342 14.66 15.63 16.38 17.68 Sch FLI
03.09.2015 57269.328 14.66 15.57 16.34 17.67 Sch FLI
Table 9: Continued.
Date J.D. (24…) I R V B Tel CCD
03.08.2014 56873.386 13.93 15.65 16.58 18.12 Sch FLI
04.08.2014 56874.407 13.92 15.59 16.69 18.08 Sch FLI
18.08.2014 56888.450 13.94 15.58 16.60 18.10 Sch FLI
19.08.2014 56889.365 13.93 15.57 16.62 18.15 Sch FLI
29.08.2014 56899.303 13.92 15.52 16.58 18.11 1.3-m ANDOR
26.11.2014 56988.181 13.93 15.57 16.59 18.12 Sch FLI
13.12.2014 57005.181 13.94 15.55 16.59 18.09 Sch FLI
14.12.2014 57006.220 13.93 15.53 16.48 - Sch FLI
21.02.2015 57074.641 13.92 15.56 16.61 18.05 Sch FLI
23.04.2015 57136.487 13.92 15.58 16.54 18.05 Sch FLI
25.04.2015 57138.491 13.93 15.57 16.58 18.06 Sch FLI
18.05.2015 57161.423 13.94 15.54 16.62 - Sch FLI
19.05.2015 57162.460 13.88 15.57 16.54 18.16 Sch FLI
21.05.2015 57164.459 13.92 15.52 16.53 18.10 Sch FLI
12.06.2015 57186.444 13.93 15.56 16.49 18.10 Sch FLI
16.07.2015 57220.364 13.92 15.56 16.46 18.14 Sch FLI
17.07.2015 57221.417 13.92 15.58 16.61 18.14 Sch FLI
11.08.2015 57246.355 13.90 15.53 16.60 18.15 1.3-m ANDOR
12.08.2015 57247.394 13.90 15.52 16.60 18.15 1.3-m ANDOR
24.08.2015 57259.337 13.93 15.56 16.56 17.89 Sch FLI
25.08.2015 57260.342 13.93 15.55 16.52 18.03 Sch FLI
03.09.2015 57269.328 13.92 15.56 16.55 18.10 Sch FLI
Table 10: Continued.
Date J.D. (24…) I R V B Tel CCD
10.04.2013 56392.510 14.44 15.99 17.10 - Sch FLI
11.04.2013 56394.482 14.46 16.02 17.19 18.68 Sch FLI
02.05.2013 56415.418 14.59 16.19 17.40 19.12 Sch FLI
15.05.2013 56428.404 14.54 15.98 17.22 - 60-cm FLI
17.05.2013 56430.408 14.54 16.07 17.26 - 60-cm FLI
19.05.2013 56432.405 14.65 16.16 17.48 - 60-cm FLI
30.05.2013 56443.367 14.58 16.19 17.38 19.20 Sch FLI
31.05.2013 56444.354 14.55 16.18 17.45 - Sch FLI
04.07.2013 56478.363 14.64 15.91 17.29 18.83 2-m VA
01.08.2013 56506.281 14.61 15.91 17.27 18.89 2-m VA
02.08.2013 56507.272 14.63 15.91 17.25 18.90 2-m VA
03.08.2013 56508.318 14.57 15.85 17.17 18.78 2-m VA
04.08.2013 56509.288 14.52 16.06 17.38 18.87 Sch FLI
05.08.2013 56510.369 14.59 16.03 17.31 18.85 60-cm FLI
05.08.2013 56510.386 14.52 16.08 17.34 18.97 Sch FLI
06.08.2013 56511.411 14.54 16.13 17.35 18.88 Sch FLI
06.08.2013 56511.413 14.61 16.17 17.33 - 60-cm FLI
07.08.2013 56512.398 14.57 16.16 17.43 19.01 Sch FLI
07.08.2013 56512.403 14.66 16.13 17.45 - 60-cm FLI
08.08.2013 56513.382 14.56 16.09 17.32 18.80 60-cm FLI
09.08.2013 56514.350 14.54 16.00 17.26 - 60-cm FLI
12.08.2013 56517.284 14.56 16.07 17.11 18.74 60-cm FLI
04.09.2013 56540.274 14.60 16.19 17.45 19.18 Sch FLI
05.09.2013 56541.322 14.58 16.12 17.33 18.94 Sch FLI
06.09.2013 56542.381 14.58 16.17 17.41 18.98 Sch FLI
07.09.2013 56543.396 14.70 15.98 17.36 18.98 2-m VA
08.09.2013 56544.264 14.77 16.08 17.45 19.07 2-m VA
11.09.2013 56547.383 14.63 16.06 17.38 18.95 60-cm FLI
14.09.2013 56550.363 14.61 16.11 17.42 - 60-cm FLI
17.09.2013 56553.282 14.58 16.06 17.30 18.79 1.3-m ANDOR
11.10.2013 56577.306 60-cm FLI
12.10.2013 56578.331 60-cm FLI
07.11.2013 56604.264 14.65 16.17 17.53 19.15 60-cm FLI
09.12.2013 56636.185 14.57 15.88 17.27 18.96 2-m VA
28.12.2013 56655.200 14.55 16.19 17.50 19.15 Sch FLI
29.12.2013 56656.180 14.53 16.04 17.25 18.66 Sch FLI
30.12.2013 56657.193 14.51 16.09 17.31 18.55 Sch FLI
23.01.2014 56681.189 14.75 16.42 17.68 19.35 Sch FLI
05.02.2014 56694.194 - 15.94 17.32 - 2-m VA
22.03.2014 56738.590 14.56 16.07 17.43 18.89 Sch FLI
21.05.2014 56799.425 14.54 16.18 17.35 18.88 Sch FLI
23.05.2014 56801.436 14.57 15.83 17.16 18.71 2-m VA
23.06.2014 56832.391 14.58 15.83 17.14 18.75 2-m VA
25.06.2014 56834.357 14.52 15.78 17.04 18.64 2-m VA
26.06.2014 56835.462 14.41 15.69 16.91 18.43 2-m VA
28.06.2014 56837.417 14.42 15.94 17.10 18.49 Sch FLI
29.06.2014 56838.398 14.45 15.97 17.19 18.63 Sch FLI
20.07.2014 56859.390 14.52 15.96 17.15 - 60-cm FLI
21.07.2014 56860.391 14.54 16.06 17.11 - 60-cm FLI
24.07.2014 56863.339 14.56 16.18 - 18.80 Sch FLI
25.07.2014 56864.356 14.52 16.24 - - Sch FLI
03.08.2014 56873.386 14.43 15.96 17.16 18.43 Sch FLI
04.08.2014 56874.407 14.50 16.11 17.34 - Sch FLI
18.08.2014 56888.450 14.46 15.98 17.15 18.49 Sch FLI
19.08.2014 56889.365 14.49 16.02 17.21 18.69 Sch FLI
29.08.2014 56899.303 14.65 16.15 17.45 19.16 1.3-m ANDOR
26.11.2014 56988.181 14.47 16.00 17.09 18.55 Sch FLI
13.12.2014 57005.181 14.67 16.30 17.55 19.11 Sch FLI
14.12.2014 57006.220 14.57 16.16 17.32 - Sch FLI
24.12.2014 57016.174 14.64 15.98 17.38 19.03 2-m VA
25.12.2014 57017.175 14.71 16.04 17.42 19.08 2-m VA
21.02.2015 57074.641 14.60 16.15 17.39 19.01 Sch FLI
23.04.2015 57136.487 14.54 16.06 17.27 18.71 Sch FLI
25.04.2015 57138.491 14.61 16.14 17.36 19.02 Sch FLI
18.05.2015 57161.423 14.50 15.99 17.18 - Sch FLI
19.05.2015 57162.460 14.50 16.01 17.22 18.68 Sch FLI
21.05.2015 57164.459 14.54 16.02 17.29 18.96 Sch FLI
24.05.2015 57167.409 14.55 15.80 17.16 18.92 2-m VA
12.06.2015 57186.444 14.50 15.99 17.15 18.85 Sch FLI
13.06.2015 57187.478 14.55 15.82 17.20 18.74 2-m VA
16.06.2015 57190.367 14.42 15.69 16.99 18.48 2-m VA
16.07.2015 57220.364 14.49 15.95 17.05 18.53 Sch FLI
17.07.2015 57221.417 14.53 16.06 17.28 18.73 Sch FLI
19.07.2015 57223.400 14.57 15.84 17.18 18.81 2-m VA
20.07.2015 57224.422 14.50 15.73 17.10 18.71 2-m VA
11.08.2015 57246.355 14.42 15.88 17.07 18.49 1.3-m ANDOR
12.08.2015 57247.394 14.52 15.99 17.20 18.69 1.3-m ANDOR
17.08.2015 57252.384 14.39 15.65 16.92 18.37 2-m VA
24.08.2015 57259.337 14.48 16.01 17.06 18.76 Sch FLI
25.08.2015 57260.342 14.48 15.98 17.08 18.79 Sch FLI
03.09.2015 57269.328 14.56 16.07 17.25 18.81 Sch FLI
04.09.2015 57270.330 14.49 15.73 17.07 18.61 2-m VA
05.09.2015 57271.323 14.58 15.84 17.16 18.86 2-m VA
06.09.2015 57272.288 14.57 15.83 17.16 18.84 2-m VA
Table 11: Continued.
Date J.D. (24…) I R V B Tel CCD
10.04.2013 56392.510 14.80 16.43 17.81 - Sch FLI
11.04.2013 56394.482 14.76 16.33 17.71 19.23 Sch FLI
02.05.2013 56415.418 14.73 16.30 17.71 19.33 Sch FLI
15.05.2013 56428.404 14.63 16.14 17.43 - 60-cm FLI
17.05.2013 56430.408 14.63 16.15 17.31 - 60-cm FLI
19.05.2013 56432.405 14.74 16.30 17.40 - 60-cm FLI
30.05.2013 56443.367 14.70 16.18 17.70 - Sch FLI
31.05.2013 56444.354 14.71 16.28 17.78 - Sch FLI
04.07.2013 56478.363 14.77 16.11 17.61 19.42 2-m VA
01.08.2013 56506.281 14.64 15.95 17.40 19.08 2-m VA
02.08.2013 56507.272 14.66 15.97 17.48 19.11 2-m VA
03.08.2013 56508.318 14.59 15.87 17.26 18.94 2-m VA
04.08.2013 56509.288 14.62 16.16 17.44 19.29 Sch FLI
05.08.2013 56510.369 14.72 16.25 17.69 - 60-cm FLI
05.08.2013 56510.386 14.70 16.23 17.56 19.13 Sch FLI
06.08.2013 56511.411 14.70 16.30 17.61 19.22 Sch FLI
06.08.2013 56511.413 14.68 16.21 17.59 19.45 60-cm FLI
07.08.2013 56512.398 14.68 16.28 17.65 19.28 Sch FLI
07.08.2013 56512.403 14.69 16.22 17.76 19.36 60-cm FLI
08.08.2013 56513.382 14.67 16.22 17.76 19.10 60-cm FLI
09.08.2013 56514.350 14.62 16.16 17.51 18.81 60-cm FLI
12.08.2013 56517.284 14.71 16.01 17.85 - 60-cm FLI
04.09.2013 56540.274 14.63 16.09 17.34 18.86 Sch FLI
05.09.2013 56541.322 14.66 16.21 17.47 19.13 Sch FLI
06.09.2013 56542.381 14.69 16.28 17.53 19.16 Sch FLI
07.09.2013 56543.396 14.76 16.01 17.42 19.14 2-m VA
08.09.2013 56544.264 14.81 16.11 17.54 19.30 2-m VA
11.09.2013 56547.383 14.70 16.22 17.80 - 60-cm FLI
14.09.2013 56550.363 14.68 16.18 17.57 19.02 60-cm FLI
17.09.2013 56553.282 14.64 16.19 17.52 19.20 1.3-m ANDOR
11.10.2013 56577.306 14.66 16.16 - - 60-cm FLI
12.10.2013 56578.331 14.64 16.16 17.45 19.27 60-cm FLI
07.11.2013 56604.264 14.72 16.27 17.72 19.36 60-cm FLI
09.12.2013 56636.185 14.72 16.07 17.54 19.32 2-m VA
28.12.2013 56655.200 14.70 16.29 17.77 - Sch FLI
29.12.2013 56656.180 14.71 16.29 17.65 19.20 Sch FLI
30.12.2013 56657.193 14.67 16.27 17.60 19.03 Sch FLI
23.01.2014 56681.189 14.64 16.18 17.48 19.21 Sch FLI
05.02.2014 56694.194 - 16.00 17.46 19.55 2-m VA
22.03.2014 56738.590 14.73 16.29 17.71 19.14 Sch FLI
21.05.2014 56799.425 14.65 16.30 17.80 - Sch FLI
23.05.2014 56801.436 14.57 15.90 17.43 19.30 2-m VA
23.06.2014 56832.391 14.62 15.87 17.28 19.00 2-m VA
25.06.2014 56834.357 14.66 15.99 17.49 19.28 2-m VA
26.06.2014 56835.462 14.60 15.88 17.33 19.09 2-m VA
28.06.2014 56837.417 14.63 16.19 17.53 19.27 Sch FLI
29.06.2014 56838.398 14.65 16.23 17.54 19.31 Sch FLI
20.07.2014 56859.390 14.72 16.31 - - 60-cm FLI
21.07.2014 56860.391 14.60 16.08 17.31 - 60-cm FLI
24.07.2014 56863.339 14.70 16.26 - - Sch FLI
25.07.2014 56864.356 14.65 16.25 - - Sch FLI
03.08.2014 56873.386 14.70 16.28 17.74 19.29 Sch FLI
04.08.2014 56874.407 14.65 16.24 17.72 - Sch FLI
18.08.2014 56888.450 14.67 16.23 17.53 19.08 Sch FLI
19.08.2014 56889.365 14.62 16.16 17.47 18.99 Sch FLI
29.08.2014 56899.303 14.60 16.16 17.51 19.21 1.3-m ANDOR
26.11.2014 56988.181 14.61 16.18 17.46 19.29 Sch FLI
13.12.2014 57005.181 14.62 16.18 17.48 19.36 Sch FLI
14.12.2014 57006.220 14.69 16.30 17.64 - Sch FLI
24.12.2014 57016.174 14.63 16.03 17.50 19.32 2-m VA
25.12.2014 57017.175 14.58 15.93 17.36 19.15 2-m VA
21.02.2015 57074.641 14.61 16.09 17.35 19.18 Sch FLI
23.04.2015 57136.487 14.69 16.27 17.60 19.15 Sch FLI
25.04.2015 57138.491 14.65 16.14 17.50 19.35 Sch FLI
18.05.2015 57161.423 14.71 16.16 17.55 - Sch FLI
19.05.2015 57162.460 14.62 16.22 17.52 19.39 Sch FLI
21.05.2015 57164.459 14.71 16.28 17.67 19.07 Sch FLI
24.05.2015 57167.409 14.57 15.86 17.29 19.13 2-m VA
12.06.2015 57186.444 14.54 16.08 17.46 19.06 Sch FLI
13.06.2015 57187.478 14.54 15.83 17.31 18.96 2-m VA
16.06.2015 57190.367 14.59 15.92 17.42 19.30 2-m VA
16.07.2015 57220.364 14.55 16.06 17.42 19.08 Sch FLI
17.07.2015 57221.417 14.64 16.20 17.62 19.13 Sch FLI
19.07.2015 57223.400 14.57 15.87 17.30 19.06 2-m VA
20.07.2015 57224.422 14.64 15.94 17.46 19.34 2-m VA
11.08.2015 57246.355 14.57 16.09 17.42 19.05 1.3-m ANDOR
12.08.2015 57247.394 14.60 16.18 17.52 19.20 1.3-m ANDOR
17.08.2015 57252.384 14.63 15.96 17.41 19.32 2-m VA
24.08.2015 57259.337 14.63 16.15 17.41 19.29 Sch FLI
25.08.2015 57260.342 14.63 16.20 17.55 19.15 Sch FLI
03.09.2015 57269.328 14.61 16.15 17.51 19.10 Sch FLI
04.09.2015 57270.330 14.56 15.82 17.21 18.99 2-m VA
05.09.2015 57271.323 14.65 15.92 17.43 19.15 2-m VA
06.09.2015 57272.288 14.46 15.68 17.02 18.66 2-m VA
Table 12: Continued.
Date J.D. (24…) I R V B Tel CCD
15.05.2013 56428.404 13.82 15.12 16.34 17.87 60-cm FLI
10.04.2013 56392.510 13.93 15.23 16.52 - Sch FLI
11.04.2013 56394.482 13.89 15.24 16.45 18.01 Sch FLI
02.05.2013 56415.418 13.94 15.25 16.48 17.98 Sch FLI
17.05.2013 56430.408 13.90 15.23 16.48 - 60-cm FLI
19.05.2013 56432.405 13.92 15.22 16.47 17.96 60-cm FLI
30.05.2013 56443.367 13.85 15.16 16.34 18.16 Sch FLI
31.05.2013 56444.354 13.82 15.10 16.28 17.90 Sch FLI
04.07.2013 56478.363 13.96 15.09 16.37 18.03 2-m VA
01.08.2013 56506.281 13.93 15.11 16.40 18.12 2-m VA
02.08.2013 56507.272 13.90 15.03 16.30 18.04 2-m VA
03.08.2013 56508.318 13.97 15.16 16.46 18.18 2-m VA
04.08.2013 56509.288 13.93 15.26 16.53 18.07 Sch FLI
05.08.2013 56510.369 14.00 15.35 16.58 18.28 60-cm FLI
05.08.2013 56510.386 14.00 15.35 16.61 18.31 Sch FLI
06.08.2013 56511.411 13.94 15.30 16.53 18.32 Sch FLI
06.08.2013 56511.413 13.94 15.30 16.56 18.18 60-cm FLI
07.08.2013 56512.398 13.98 15.33 16.58 18.16 Sch FLI
07.08.2013 56512.403 13.98 15.28 16.60 18.30 60-cm FLI
08.08.2013 56513.382 13.96 15.31 16.57 18.18 60-cm FLI
09.08.2013 56514.350 13.86 15.22 16.45 18.15 60-cm FLI
12.08.2013 56517.284 13.83 15.09 16.32 17.89 60-cm FLI
04.09.2013 56540.274 13.94 15.32 16.56 18.22 Sch FLI
05.09.2013 56541.322 13.86 15.20 16.41 17.99 Sch FLI
06.09.2013 56542.381 13.90 15.28 16.48 18.05 Sch FLI
07.09.2013 56543.396 13.99 15.16 16.47 18.18 2-m VA
08.09.2013 56544.264 14.08 15.26 16.53 18.20 2-m VA
11.09.2013 56547.383 14.07 15.43 16.73 18.67 60-cm FLI
14.09.2013 56550.363 13.98 15.28 16.61 18.51 60-cm FLI
17.09.2013 56553.282 13.95 15.33 16.61 18.27 1.3-m ANDOR
11.10.2013 56577.306 13.99 15.29 16.55 18.44 60-cm FLI
12.10.2013 56578.331 13.92 15.27 16.48 18.31 60-cm FLI
07.11.2013 56604.264 14.13 15.57 16.82 18.64 60-cm FLI
09.12.2013 56636.185 13.96 15.16 16.47 18.18 2-m VA
28.12.2013 56655.200 13.93 15.32 16.57 18.12 Sch FLI
29.12.2013 56656.180 13.88 15.21 16.39 18.00 Sch FLI
30.12.2013 56657.193 14.02 15.38 16.62 18.30 Sch FLI
23.01.2014 56681.189 13.93 15.27 16.50 18.13 Sch FLI
05.02.2014 56694.194 - 15.42 16.78 18.71 2-m VA
22.03.2014 56738.590 13.94 15.31 16.54 18.26 Sch FLI
21.05.2014 56799.425 14.09 15.47 16.74 - Sch FLI
23.05.2014 56801.436 13.95 15.13 16.45 18.22 2-m VA
23.06.2014 56832.391 14.04 15.26 16.58 18.36 2-m VA
25.06.2014 56834.357 13.94 15.12 16.42 18.13 2-m VA
26.06.2014 56835.462 13.90 15.10 16.40 18.10 2-m VA
28.06.2014 56837.417 14.04 15.47 16.73 18.51 Sch FLI
29.06.2014 56838.398 14.15 15.61 16.85 18.44 Sch FLI
20.07.2014 56859.390 13.94 15.30 16.45 18.06 60-cm FLI
21.07.2014 56860.391 14.06 15.43 16.69 - 60-cm FLI
24.07.2014 56863.339 13.98 15.34 - 18.25 Sch FLI
25.07.2014 56864.356 13.94 15.29 - - Sch FLI
03.08.2014 56873.386 14.14 15.53 16.81 18.45 Sch FLI
04.08.2014 56874.407 13.99 15.37 16.71 - Sch FLI
18.08.2014 56888.450 14.02 15.48 16.70 18.38 Sch FLI
19.08.2014 56889.365 13.99 15.42 16.69 18.30 Sch FLI
29.08.2014 56899.303 13.91 15.26 16.50 18.12 1.3-m ANDOR
26.11.2014 56988.181 14.18 15.64 16.87 18.59 Sch FLI
13.12.2014 57005.181 14.14 15.60 16.81 18.75 Sch FLI
14.12.2014 57006.220 13.97 15.38 16.60 - Sch FLI
24.12.2014 57016.174 13.86 15.07 16.35 18.02 2-m VA
25.12.2014 57017.175 14.06 15.31 16.62 18.42 2-m VA
21.02.2015 57074.641 13.94 15.32 16.49 18.18 Sch FLI
23.04.2015 57136.487 13.98 15.39 16.58 18.25 Sch FLI
25.04.2015 57138.491 13.93 15.29 16.50 18.10 Sch FLI
18.05.2015 57161.423 13.95 15.29 16.52 17.99 Sch FLI
19.05.2015 57162.460 14.00 15.39 16.60 18.43 Sch FLI
21.05.2015 57164.459 14.04 15.41 16.65 18.39 Sch FLI
24.05.2015 57167.409 14.00 15.17 16.53 18.40 2-m VA
12.06.2015 57186.444 14.05 15.44 16.66 18.39 Sch FLI
13.06.2015 57187.478 13.92 15.13 16.44 18.17 2-m VA
16.06.2015 57190.367 13.95 15.17 16.52 18.30 2-m VA
16.07.2015 57220.364 13.91 15.26 16.44 18.13 Sch FLI
17.07.2015 57221.417 13.94 15.32 16.55 18.15 Sch FLI
19.07.2015 57223.400 14.11 15.34 16.66 18.41 2-m VA
20.07.2015 57224.422 14.20 15.45 16.83 18.61 2-m VA
11.08.2015 57246.355 14.08 15.50 16.79 18.48 1.3-m ANDOR
12.08.2015 57247.394 14.00 15.40 16.66 18.34 1.3-m ANDOR
17.08.2015 57252.384 14.05 15.25 16.56 18.34 2-m VA
24.08.2015 57259.337 13.95 15.32 16.53 18.16 Sch FLI
25.08.2015 57260.342 14.06 15.43 16.66 18.35 Sch FLI
03.09.2015 57269.328 13.87 15.20 16.33 17.95 Sch FLI
04.09.2015 57270.330 13.98 15.17 16.49 18.24 2-m VA
05.09.2015 57271.323 13.91 15.09 16.39 18.13 2-m VA
06.09.2015 57272.288 14.04 15.23 16.54 18.26 2-m VA
Table 13: Continued.
Date J.D. (24…) I R V B Tel CCD
10.04.2013 56392.510 11.56 12.14 12.79 13.87 Sch FLI
11.04.2013 56394.482 11.56 12.16 12.83 13.91 Sch FLI
02.05.2013 56415.418 11.56 12.17 12.82 13.96 Sch FLI
15.05.2013 56428.404 11.58 12.15 12.87 13.92 60-cm FLI
17.05.2013 56430.408 11.59 12.21 12.88 13.94 60-cm FLI
19.05.2013 56432.405 11.56 12.17 12.87 13.90 60-cm FLI
30.05.2013 56443.367 11.57 12.16 12.84 13.94 Sch FLI
31.05.2013 56444.354 11.57 12.15 12.83 13.94 Sch FLI
04.08.2013 56509.288 11.57 12.17 12.88 13.96 Sch FLI
05.08.2013 56510.369 11.56 12.16 12.88 13.93 60-cm FLI
05.08.2013 56510.386 11.56 12.16 12.83 13.95 Sch FLI
06.08.2013 56511.411 11.58 12.17 12.85 13.96 Sch FLI
06.08.2013 56511.413 11.56 12.19 12.86 13.95 60-cm FLI
07.08.2013 56512.398 11.54 12.12 12.80 13.90 Sch FLI
07.08.2013 56512.403 11.51 12.10 12.82 13.89 60-cm FLI
08.08.2013 56513.382 11.53 12.17 12.84 14.01 60-cm FLI
09.08.2013 56514.350 11.53 12.14 12.86 13.92 60-cm FLI
12.08.2013 56517.284 11.53 12.11 12.85 13.94 60-cm FLI
04.09.2013 56540.274 11.59 12.18 12.85 13.99 Sch FLI
05.09.2013 56541.322 11.57 12.17 12.84 13.93 Sch FLI
06.09.2013 56542.381 11.58 12.19 12.85 13.94 Sch FLI
11.09.2013 56547.383 11.56 12.16 12.86 13.96 60-cm FLI
14.09.2013 56550.363 11.59 12.18 12.89 14.00 60-cm FLI
12.10.2013 56578.331 11.48 12.13 12.80 14.03 60-cm FLI
28.12.2013 56655.200 11.55 12.14 12.82 13.90 Sch FLI
29.12.2013 56656.180 11.57 12.16 12.84 13.94 Sch FLI
30.12.2013 56657.193 11.56 12.13 12.82 13.92 Sch FLI
23.01.2014 56681.189 11.57 12.16 12.83 13.96 Sch FLI
22.03.2014 56738.590 11.56 12.18 12.85 13.96 Sch FLI
21.05.2014 56799.425 11.58 12.16 12.84 13.96 Sch FLI
28.06.2014 56837.417 11.58 12.18 12.85 13.95 Sch FLI
29.06.2014 56838.398 11.57 12.19 12.86 13.94 Sch FLI
21.07.2014 56860.391 11.50 12.16 12.79 13.93 60-cm FLI
24.07.2014 56863.339 11.58 12.18 - 13.98 Sch FLI
25.07.2014 56864.356 11.59 12.21 - - Sch FLI
03.08.2014 56873.386 11.56 12.16 12.84 13.95 Sch FLI
18.08.2014 56888.450 11.58 12.19 12.85 13.96 Sch FLI
19.08.2014 56889.365 11.56 12.17 12.86 13.96 Sch FLI
26.11.2014 56988.181 11.60 12.19 12.87 13.98 Sch FLI
13.12.2014 57005.181 11.54 12.17 12.86 13.96 Sch FLI
14.12.2014 57006.220 11.58 12.20 12.92 - Sch FLI
21.02.2015 57074.641 11.61 12.22 12.93 14.05 Sch FLI
23.04.2015 57136.487 11.59 12.24 12.92 14.04 Sch FLI
25.04.2015 57138.491 11.61 12.24 12.92 14.04 Sch FLI
18.05.2015 57161.423 11.61 12.22 12.93 14.04 Sch FLI
19.05.2015 57162.460 11.60 12.23 12.92 14.06 Sch FLI
21.05.2015 57164.459 11.62 12.25 12.93 14.06 Sch FLI
12.06.2015 57186.444 11.60 12.23 12.97 14.04 Sch FLI
16.07.2015 57220.364 11.60 12.23 12.87 14.03 Sch FLI
17.07.2015 57221.417 11.60 12.22 12.90 14.05 Sch FLI
24.08.2015 57259.337 11.60 12.23 12.94 14.04 Sch FLI
25.08.2015 57260.342 11.59 12.23 12.93 14.04 Sch FLI
03.09.2015 57269.328 11.58 12.21 12.93 14.01 Sch FLI
Table 14: Continued.
Date J.D. (24…) I R Tel CCD
10.04.2013 56392.510 16.11 - Sch FLI
11.04.2013 56394.482 16.09 - Sch FLI
02.05.2013 56415.418 16.19 - Sch FLI
15.05.2013 56428.404 16.26 - 60-cm FLI
17.05.2013 56430.408 16.31 - 60-cm FLI
19.05.2013 56432.405 16.30 - 60-cm FLI
30.05.2013 56443.367 16.10 - Sch FLI
31.05.2013 56444.354 16.22 - Sch FLI
01.08.2013 56506.281 16.09 18.61 2-m VA
02.08.2013 56507.272 16.14 19.02 2-m VA
03.08.2013 56508.318 16.11 18.64 2-m VA
04.08.2013 56509.288 16.27 - Sch FLI
05.08.2013 56510.369 16.11 - 60-cm FLI
05.08.2013 56510.386 16.23 - Sch FLI
06.08.2013 56511.411 16.21 - Sch FLI
06.08.2013 56511.413 16.26 - 60-cm FLI
07.08.2013 56512.398 16.27 - Sch FLI
07.08.2013 56512.403 16.13 - 60-cm FLI
08.08.2013 56513.382 16.23 - 60-cm FLI
09.08.2013 56514.350 16.17 - 60-cm FLI
12.08.2013 56517.284 16.31 - 60-cm FLI
04.09.2013 56540.274 16.25 - Sch FLI
05.09.2013 56541.322 16.18 - Sch FLI
06.09.2013 56542.381 16.23 - Sch FLI
11.09.2013 56547.383 16.23 - 60-cm FLI
14.09.2013 56550.363 16.22 - 60-cm FLI
17.09.2013 56553.282 16.08 - 1.3-m ANDOR
11.10.2013 56577.306 16.18 - 60-cm FLI
12.10.2013 56578.331 16.22 - 60-cm FLI
07.11.2013 56604.264 16.22 - 60-cm FLI
09.12.2013 56636.185 15.84 18.91 2-m VA
28.12.2013 56655.200 16.19 - Sch FLI
29.12.2013 56656.180 16.20 - Sch FLI
30.12.2013 56657.193 16.26 - Sch FLI
23.01.2014 56681.189 16.19 - Sch FLI
22.03.2014 56738.590 16.22 - Sch FLI
21.05.2014 56799.425 16.13 - Sch FLI
23.05.2014 56801.436 16.18 18.71 2-m VA
23.06.2014 56832.391 16.15 18.72 2-m VA
25.06.2014 56834.357 - 18.64 2-m VA
26.06.2014 56835.462 16.14 18.68 2-m VA
28.06.2014 56837.417 16.24 - Sch FLI
29.06.2014 56838.398 16.14 - Sch FLI
20.07.2014 56859.390 16.09 - 60-cm FLI
21.07.2014 56860.391 16.13 - 60-cm FLI
24.07.2014 56863.339 16.13 - Sch FLI
25.07.2014 56864.356 16.08 - Sch FLI
03.08.2014 56873.386 16.21 - Sch FLI
04.08.2014 56874.407 16.18 - Sch FLI
18.08.2014 56888.450 16.11 - Sch FLI
19.08.2014 56889.365 16.19 - Sch FLI
29.08.2014 56899.303 16.15 - 1.3-m ANDOR
26.11.2014 56988.181 16.22 - Sch FLI
13.12.2014 57005.181 16.18 - Sch FLI
14.12.2014 57006.220 16.21 - Sch FLI
24.12.2014 57016.174 16.09 18.68 2-m VA
25.12.2014 57017.175 16.11 18.72 2-m VA
21.02.2015 57074.641 16.21 - Sch FLI
23.04.2015 57136.487 16.29 - Sch FLI
25.04.2015 57138.491 16.18 - Sch FLI
18.05.2015 57161.423 16.26 - Sch FLI
19.05.2015 57162.460 16.13 - Sch FLI
21.05.2015 57164.459 16.24 - Sch FLI
24.05.2015 57167.409 16.17 18.48 2-m VA
12.06.2015 57186.444 16.25 - Sch FLI
13.06.2015 57187.478 16.04 18.47 2-m VA
16.06.2015 57190.367 16.06 18.51 2-m VA
16.07.2015 57220.364 16.15 - Sch FLI
17.07.2015 57221.417 16.25 - Sch FLI
19.07.2015 57223.400 16.11 18.50 2-m VA
20.07.2015 57224.422 16.12 18.50 2-m VA
11.08.2015 57246.355 16.11 19.91 1.3-m ANDOR
12.08.2015 57247.394 16.11 19.88 1.3-m ANDOR
24.08.2015 57259.337 16.19 - Sch FLI
25.08.2015 57260.342 16.21 - Sch FLI
03.09.2015 57269.328 16.22 - Sch FLI
04.09.2015 57270.330 16.12 18.71 2-m VA
05.09.2015 57271.323 16.17 18.58 2-m VA
06.09.2015 57272.288 16.16 18.52 2-m VA
Table 15: Continued.
Date J.D. (24…) I R V B Tel CCD
10.04.2013 56392.510 14.98 - - - Sch FLI
11.04.2013 56394.482 14.92 17.30 - - Sch FLI
02.05.2013 56415.418 14.99 17.29 - - Sch FLI
15.05.2013 56428.404 15.05 17.25 - - 60-cm FLI
17.05.2013 56430.408 14.95 17.30 - - 60-cm FLI
19.05.2013 56432.405 15.10 16.95 - - 60-cm FLI
30.05.2013 56443.367 14.98 17.43 - - Sch FLI
31.05.2013 56444.354 14.88 17.36 - - Sch FLI
04.07.2013 56478.363 15.24 16.82 18.68 - 2-m VA
01.08.2013 56506.281 15.22 16.88 18.76 - 2-m VA
02.08.2013 56507.272 15.09 16.69 18.49 - 2-m VA
03.08.2013 56508.318 15.12 16.76 18.62 - 2-m VA
04.08.2013 56509.288 14.94 17.19 19.06 - Sch FLI
05.08.2013 56510.369 14.99 17.02 - - 60-cm FLI
05.08.2013 56510.386 14.87 16.99 18.93 - Sch FLI
06.08.2013 56511.411 14.90 17.07 18.85 - Sch FLI
06.08.2013 56511.413 15.04 17.02 18.54 - 60-cm FLI
07.08.2013 56512.398 14.86 17.04 18.84 - Sch FLI
07.08.2013 56512.403 14.98 17.04 18.73 - 60-cm FLI
08.08.2013 56513.382 14.97 17.02 18.76 - 60-cm FLI
09.08.2013 56514.350 14.99 17.00 18.71 - 60-cm FLI
12.08.2013 56517.284 14.94 16.99 - - 60-cm FLI
04.09.2013 56540.274 14.97 17.13 19.01 - Sch FLI
05.09.2013 56541.322 14.90 17.08 18.66 - Sch FLI
06.09.2013 56542.381 14.95 17.10 18.62 - Sch FLI
07.09.2013 56543.396 15.09 16.68 18.51 - 2-m VA
08.09.2013 56544.264 15.07 16.67 18.42 - 2-m VA
11.09.2013 56547.383 14.96 17.01 - - 60-cm FLI
14.09.2013 56550.363 14.95 17.21 18.82 - 60-cm FLI
17.09.2013 56553.282 14.92 16.91 18.55 - 1.3-m ANDOR
11.10.2013 56577.306 - 60-cm FLI
12.10.2013 56578.331 - 60-cm FLI
07.11.2013 56604.264 15.16 17.48 - - 60-cm FLI
09.12.2013 56636.185 15.34 17.01 18.94 - 2-m VA
28.12.2013 56655.200 15.19 - - - Sch FLI
29.12.2013 56656.180 15.27 17.58 19.30 - Sch FLI
30.12.2013 56657.193 15.06 17.43 19.14 - Sch FLI
23.01.2014 56681.189 15.09 17.39 19.19 - Sch FLI
05.02.2014 56694.194 - 17.02 19.04 - 2-m VA
22.03.2014 56738.590 15.07 17.51 19.27 - Sch FLI
21.05.2014 56799.425 15.24 17.61 - - Sch FLI
23.05.2014 56801.436 15.31 16.94 18.79 - 2-m VA
23.06.2014 56832.391 15.15 16.74 18.57 - 2-m VA
25.06.2014 56834.357 15.20 16.87 18.83 - 2-m VA
26.06.2014 56835.462 15.29 16.91 18.84 - 2-m VA
28.06.2014 56837.417 15.10 17.43 19.05 - Sch FLI
29.06.2014 56838.398 15.21 17.60 19.49 - Sch FLI
20.07.2014 56859.390 14.95 16.95 - - 60-cm FLI
21.07.2014 56860.391 14.95 16.95 - - 60-cm FLI
24.07.2014 56863.339 15.01 17.17 - - Sch FLI
25.07.2014 56864.356 15.04 17.47 - - Sch FLI
03.08.2014 56873.386 15.00 17.29 19.10 - Sch FLI
04.08.2014 56874.407 15.17 17.73 - - Sch FLI
18.08.2014 56888.450 15.15 17.57 - - Sch FLI
19.08.2014 56889.365 15.04 17.36 19.21 - Sch FLI
29.08.2014 56899.303 15.21 17.20 18.98 - 1.3-m ANDOR
26.11.2014 56988.181 15.06 17.46 18.90 - Sch FLI
13.12.2014 57005.181 15.12 17.58 18.89 - Sch FLI
14.12.2014 57006.220 15.15 17.56 19.40 - Sch FLI
24.12.2014 57016.174 15.16 16.84 18.75 - 2-m VA
25.12.2014 57017.175 15.30 16.98 18.86 - 2-m VA
21.02.2015 57074.641 15.02 17.08 18.72 - Sch FLI
23.04.2015 57136.487 15.06 17.07 18.78 - Sch FLI
25.04.2015 57138.491 14.95 16.96 18.61 - Sch FLI
18.05.2015 57161.423 15.14 17.06 - - Sch FLI
19.05.2015 57162.460 14.98 16.91 - - Sch FLI
21.05.2015 57164.459 15.07 17.04 18.61 - Sch FLI
24.05.2015 57167.409 15.00 16.58 18.41 20.39 2-m VA
12.06.2015 57186.444 15.05 17.01 18.58 - Sch FLI
13.06.2015 57187.478 15.20 16.81 18.77 20.24 2-m VA
16.06.2015 57190.367 15.09 16.68 18.56 - 2-m VA
16.07.2015 57220.364 14.98 16.97 18.51 - Sch FLI
17.07.2015 57221.417 14.98 17.00 18.46 - Sch FLI
19.07.2015 57223.400 14.97 16.60 18.39 20.49 2-m VA
20.07.2015 57224.422 14.96 16.49 18.32 20.41 2-m VA
11.08.2015 57246.355 15.06 17.03 18.70 - 1.3-m ANDOR
12.08.2015 57247.394 14.98 16.96 18.57 - 1.3-m ANDOR
17.08.2015 57252.384 15.18 16.78 18.55 - 2-m VA
24.08.2015 57259.337 15.07 17.00 - - Sch FLI
25.08.2015 57260.342 15.09 17.14 18.58 - Sch FLI
03.09.2015 57269.328 15.20 17.22 19.01 - Sch FLI
04.09.2015 57270.330 15.19 16.84 18.84 - 2-m VA
05.09.2015 57271.323 15.10 16.66 18.37 20.24 2-m VA
06.09.2015 57272.288 15.12 16.66 18.44 - 2-m VA
Table 16: Continued.
Date J.D. (24…) I R V B Tel CCD
10.04.2013 56392.510 11.61 11.86 12.28 12.99 Sch FLI
11.04.2013 56394.482 11.61 11.87 12.28 13.04 Sch FLI
02.05.2013 56415.418 11.63 11.87 12.26 13.05 Sch FLI
15.05.2013 56428.404 11.63 11.90 12.29 13.04 60-cm FLI
17.05.2013 56430.408 11.65 11.91 12.33 13.05 60-cm FLI
30.05.2013 56443.367 11.62 11.84 12.29 13.06 Sch FLI
31.05.2013 56444.354 11.62 11.85 12.26 13.05 Sch FLI
04.08.2013 56509.288 11.61 11.86 12.29 13.05 Sch FLI
05.08.2013 56510.369 11.63 11.90 12.32 13.03 60-cm FLI
05.08.2013 56510.386 11.61 11.86 12.26 13.06 Sch FLI
06.08.2013 56511.411 11.62 11.86 12.26 13.05 Sch FLI
06.08.2013 56511.413 11.62 11.89 12.29 13.02 60-cm FLI
07.08.2013 56512.398 11.62 11.87 12.28 13.06 Sch FLI
07.08.2013 56512.403 11.61 11.86 12.30 13.00 60-cm FLI
08.08.2013 56513.382 11.59 11.88 12.28 13.07 60-cm FLI
09.08.2013 56514.350 11.60 11.89 12.31 13.01 60-cm FLI
12.08.2013 56517.284 11.58 11.84 12.27 12.99 60-cm FLI
04.09.2013 56540.274 11.62 11.86 12.26 13.05 Sch FLI
05.09.2013 56541.322 11.61 11.86 12.27 13.02 Sch FLI
06.09.2013 56542.381 11.62 11.88 12.28 13.02 Sch FLI
11.09.2013 56547.383 11.62 11.88 12.30 13.03 60-cm FLI
14.09.2013 56550.363 11.66 11.91 12.33 13.08 60-cm FLI
28.12.2013 56655.200 11.61 11.86 12.26 13.02 Sch FLI
29.12.2013 56656.180 11.63 11.87 12.27 13.04 Sch FLI
30.12.2013 56657.193 11.62 11.86 12.27 13.03 Sch FLI
23.01.2014 56681.189 11.62 11.86 12.27 13.06 Sch FLI
22.03.2014 56738.590 11.63 11.88 12.28 13.07 Sch FLI
21.05.2014 56799.425 11.63 11.86 12.27 13.07 Sch FLI
28.06.2014 56837.417 11.62 11.86 12.27 13.03 Sch FLI
29.06.2014 56838.398 11.62 11.88 12.27 13.01 Sch FLI
24.07.2014 56863.339 11.63 11.90 - 13.06 Sch FLI
25.07.2014 56864.356 11.64 11.90 - - Sch FLI
03.08.2014 56873.386 11.62 11.86 12.27 13.04 Sch FLI
18.08.2014 56888.450 11.63 11.87 12.27 13.03 Sch FLI
19.08.2014 56889.365 11.62 11.86 12.28 13.05 Sch FLI
26.11.2014 56988.181 11.65 11.88 12.26 13.06 Sch FLI
13.12.2014 57005.181 11.53 11.85 12.17 12.99 Sch FLI
14.12.2014 57006.220 11.60 11.90 12.19 - Sch FLI
21.02.2015 57074.641 11.63 11.91 12.25 13.13 Sch FLI
23.04.2015 57136.487 11.61 11.90 12.26 13.08 Sch FLI
25.04.2015 57138.491 11.62 11.90 12.30 13.10 Sch FLI
19.05.2015 57162.460 11.62 11.89 12.26 13.10 Sch FLI
12.06.2015 57186.444 11.62 11.90 12.24 13.09 Sch FLI
16.07.2015 57220.364 11.62 11.92 12.28 13.12 Sch FLI
17.07.2015 57221.417 11.63 11.93 12.33 13.17 Sch FLI
24.08.2015 57259.337 11.65 11.96 12.28 13.16 Sch FLI
25.08.2015 57260.342 11.63 11.92 - 13.12 Sch FLI
03.09.2015 57269.328 11.64 11.92 - 13.10 Sch FLI
Table 17: Continued.
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