FERMI constraints on the high energy, \sim 1GeV, emission of long GRBs

FERMI constraints on the high energy, ~1 GeV, emission of long GRBs

Key Words.:
gamma rays: bursts

Abstract

Context:

Aims:We investigate the constraints imposed on the luminosity function (LF) of long duration Gamma Ray Bursts (LGRBs) by the flux distribution of bursts detected by the GBM at  MeV, and the implications of the non detection of the vast majority, 95%, of the LGRBs at higher energy,  GeV, by the LAT detector.

Methods:We find a LF that is consistent with those determined by BATSE and Swift. The non detections by LAT set upper limits on the ratio of the prompt fluence at  GeV to that at  MeV. The upper limits are more stringent for brighter bursts, with for of the bursts. This implies that for most bursts the prompt  GeV emission may be comparable to the  MeV emission, but can not dominate it. The value of is not universal, with a spread of (at least) an order of magnitude around . For several bright bursts with reliable determination of the photon spectral index at  MeV, the LAT non detection implies an upper limit to the  MeV flux which is of the flux obtained by extrapolating the  MeV flux to high energy.

Results: For the widely accepted models, in which the  MeV power-law photon spectrum reflects the power-law energy distribution of fast cooling electrons, this suggests that either the electron energy distribution does not follow a power-law over a wide energy range, or that the high energy photons are absorbed. Requiring an order unity pair production optical depth at 100 MeV sets an upper limit for the Lorentz factor, .

Conclusions:

1 Introduction

Gamma ray bursts (GRBs) are the most powerful explosions in the universe, with apparent (isotropic equivalent) energy output sometimes exceeding ergs. While it is widely accepted that GRBs are produced by the dissipation of energy in highly relativistic winds driven by compact objects (see, e.g., Mészáros 2006, Piran 2004 and Waxman 2003 for reviews) the physics of wind generation and radiation production is not yet understood. It is not known, for example, whether the wind luminosity is carried, as commonly assumed, by kinetic energy or by Poynting flux (e.g. Drenkhahn & Spruit 2002, Lyutikov et al. 2003), whether the radiating particles are accelerated by the dissipation of magnetic flux or by internal shocks dissipating kinetic energy, and whether the emission is dominated by synchrotron or inverse-Compton radiation of accelerated electrons, as commonly assumed, or by hadronic energy loss of accelerated protons (see Dermer & Fryer 2008 and references therein).

GRBs were detected by instruments sensitive mainly in the 100 to 1000 keV range like BATSE (Paciesas et al. 1999) and the GRBM on BeppoSAX (Guidorzi et al. 2004). Measurements at high energy were limited by the lower sensitivity and/or the smaller field of view of higher energy instruments (e.g. CGRO/EGRET- Dingus 1995, Hurley et al. 1994, Gonzalez et al. 1994; AGILE/GRID-Marisaldi et al. 2009, Giuliani et al. 2008, Giuliani et al. 2010). The improved high energy,  GeV, sensitivity and field of view of the instruments on board the Fermi satellite (Atwood et al. 2009, Band et al. 2009) are expected to improve the quantity and quality of high energy GRB data, and may therefore provide qualitatively new constraints on models.

The main goal of this paper is to determine the implications of the non-detection of the vast majority of long duration ( s) GRBs by Fermi’s LAT detector. We first show in § 2 that the LF of LGRBs detected by Fermi’s GBM at  MeV is consistent with those inferred from BATSE and Swift observations, and that these instruments sample the LF in a similar manner. We then derive in § 3 the constraints on the  MeV emission implied by LAT non-detections. In § 4 we compare our results with those inferred from the analysis of EGRET data (Gonzalez Sanchez 2005). Our results are summarized and their implications are discussed in § 5.

2 The luminosity function of the GBM sample

2.1 The GBM, BATSE and Swift-BAT samples

Our methodology follows that of Guetta et al. (2005) and of Guetta & Piran (2007). We consider all long ( seconds) bursts detected by the GBM until February 2010 (see Table 2) and compare the distribution of their peak fluxes with that of LGRBs detected by BATSE and Swift. Since the energy dependent sensitivity of the different instruments is different, we convert the GBM fluxes to equivalent fluxes in the 50-300 keV band, which is the band used by BATSE for GRB triggers. This conversion is carried out assuming that the energy spectrum around the light curve peak is well described by the spectral model that has been adopted to fit the time average spectrum. The spectral model parameters have been collected from the literature (mainly GCN circulars) and are reported in Table 2.

We have excluded from our analysis GRB081126, which has 2 pulses, because the measurements reported in GCN 8589 are inconsistent: the peak flux and fluence of the event are reported to be smaller than those reported for the individual pulses. We have kept GRB090423 in our analysis, despite the debate regarding its classification as a long burst (see Salvaterra et al. 2009) since its duration does satisfy  s.

For bursts reported in Table 2 with spectra fitted by a ”Band law”, for and for , we find , , and  keV. Using these average parameters, we estimate, based on Band (2003), a GBM sensitivity in the 50-300 keV band of 0.6 ph cm s. For our LF analysis we use only the 144 long ( s) GBM bursts with peak flux higher than that threshold.

In the BATSE sample we have included all LGRBs detected while the BATSE onboard trigger was set to a significance of 5.5  over background in at least two detectors in the energy range of 50-300 keV. Among those we selected the bursts for which the peak flux in 1024 ms time bins is higher than the BATSE threshold for long bursts reported by Band (2003), 0.25 ph cm s. This yields a sample of 1425 bursts.

For Swift we consider LGRBs detected until September 2009 in the energy range 15-150 keV. We convert the BAT 15-150 keV peak fluxes to fluxes in the 50-300 keV band using the BAT peak fluxes and spectral parameters provided by the Swift team1. We consider only the bursts with peak fluxes above the threshold of ph cm s (Gorosabel et al. 2004, Band 2003), yielding a sample of 259 GRBs.

The flux distributions of bursts included in the samples described above are shown in figure 1.

Figure 1: The flux distributions of bursts included in the BATSE, Swift and GBM samples (see text). Shown are the number of bursts detected within 20 equally spaced intervals of log peak flux (in the 50-300 keV band). Error bars derived assuming Poisson statistics.

2.2 Luminosity function and comoving rate

The method used to derive the luminosity function is essentially the same as that used by Schmidt (1999), Guetta et al. (2005) and Guetta and Piran (2007). We consider a broken power law luminosity function,

(1)

with , and independent of redshift, and a (comoving) rate evolving with redshift following the Porciani & Madau (2001) star formation rate,

(2)

The cosmological ”k correction” is determined adopting an effective spectral index in the observed range of 50-300 keV band of -1.6 () (see, e.g., Guetta and Piran 2007).

In order to determine we use Monte Carlo simulations to generate an ensemble of distributions of burst peak fluxes, that would have been detected by the various instruments for a given set of values. We find the best-fitting LF parameters and their uncertainty by minimization. The results are reported in Table 1. The LF parameters derived from the different samples are consistent with each other. Note, that the luminosity considered here is the ”isotropic” equivalent luminosity.

sample Rate(z=0)2 [50-300] keV a a /D.O.F.3
 erg/s
GBM 1.1
BATSE 1.1
Swift 0.95
4
Table 1: Best fit LF parameters

3 Constraints on the  MeV emission implied by LAT non-detections

Out of the 205 LGRBs detected by the GBM, only a few,  12 bursts, have been detected above 30 MeV by the LAT telescope. Figures 2 and 3 present the upper limits implied by the LAT non-detection on the ratio of the prompt emission fluences at 100 MeV and 1 MeV. We have included in the burst sample shown in the figure the 121 LGRBs for which an accurate determination of the 1 MeV fluence is possible based on the fluence measured by the Fermi GBM and on reliable spectral fit parameters (see table 2)789, and for which the reported LAT bore sight angle is less than (as the LAT effective area is very small for bursts observed at larger angles). The upper limit on the  MeV fluence implied by the LAT non-detection is derived as follows.

Figure 2: The upper limits implied by the LAT non-detections on the ratio of the 100 MeV to 1 MeV fluences, for  MeV, during the prompt emission, assuming a differential photon spectrum above  MeV. Also shown (red diamonds) are the measured ratios for GRBs detected by the LAT (GRB080825C, GRB080916C, GRB090217, GRB090323, GRB090328, GRB090626, GRB090902B, GRB090926A, GRB091003, reported in Ghisellini et al. 2010 and Abdo et al. 2010). The 100 MeV specific fluence was derived for these bursts from the reported  MeV fluence assuming above  MeV.

A GRB is tagged as detected by the LAT if the number of photons detected, , exceeds 10 and exceeds a fluctuation of the background (Band et al. 2009, Atwood et al. 2009). For the current analysis, it is sufficient to consider the criterion, since the number of background events detected during the characteristic time of the prompt  MeV gamma-ray emission,  s, is low (, i.e. is above a 5 background fluctuation). Following Band et al. (2009), the expected number of counts from a burst with a time integrated differential photon flux (i.e. differential photon fluence) is

(3)

where is the effective area (taken from Atwood et al. 2009) that depends on the direction from which the burst is observed, , MeV and GeV.

Figure 3: Same as figure 2, assuming a differential photon spectrum above  MeV.

The upper limits on the  MeV fluences shown in figures 2 and 3 are obtained by requiring where is the fluence for which . Since the number of events detected for bursts with fluence that produces, on average, events is Poisson distributed with an average equal to , the upper limits on the fluxes shown in the figure are confidence level upper limits. The upper limits on the fluence for confidence levels of 70% and 99.7% are 1.2 and 2 times higher respectively.

Figure 4: A histogram representation of the upper limits on, and measured values of, , presented in fig. 2.

The effective area of the LAT is roughly proportional to in the energy range of 100 MeV to 1 GeV (and roughly energy independent between 1 GeV and 10 GeV). This implies that the LAT flux sensitivity is roughly energy independent between 100 MeV and 1 GeV, and that the upper limit on implies an upper limit on the 0.1–1 GeV fluence, which is independent of the spectrum . Indeed, the upper limits on , the 100 MeV to 1 MeV fluence ratio, obtained assuming are higher by a factor of than those obtained for a , implying that the upper limits on the 0.1–1 GeV fluence obtained for both spectral shapes are similar. Denoting by the upper limit obtained on assuming , the upper limit on the 0.1–1 GeV fluence is , the upper limit on the 1–10 GeV fluence is few times higher, and the upper limit on the ratio of the 0.1–1 GeV fluence and the 0.1–1 MeV fluence is . We find for of the bursts respectively. Figure 4 presents a histogram of the distribution of upper limits on .

Figure 5: Upper limits implied by LAT non-detections on the ratio between the 100 MeV fluence and the 100 MeV fluence obtained by extrapolation to 100 MeV of the  MeV spectrum of the GBM detected photons. is the spectral index describing the high energy part of the GBM spectrum, . Also shown are the measured values of for LAT detected GRBs (red).
Figure 6: A histogram representation of the results of fig. 5.

In figure 5 we present the upper limits implied by the LAT non-detection on the ratio between the 100 MeV fluence and the 100 MeV fluence obtained by extrapolation to 100 MeV of the  MeV spectrum of the GBM detected photons. For this comparison, we have used only the bursts with spectra which are well fitted by a ”Band function” and for which the bore sight angle is . We have excluded from the sample shown in the figure bursts for which the GBM spectrum is not fitted by a Band law, i.e. fitted by either a power-law with exponential suppression (which predicts negligible flux at 100 MeV) or by a single power-law (for which a spectral break above 1 MeV is not unexpected). A histogram representation of the results of fig. 5 is shown in fig. 6. The figures show that for at least a few bursts the non detection by LAT implies a significant suppression of the 100 MeV flux compared to that expected from an extrapolation to high energy of the  MeV power-law spectrum.

4 Comparison with EGRET’s results

We compare in this section our results with those obtained by González Sánchez (2005) and Ando et al. (2008) from the non detection by EGRET of bursts detected by BATSE. EGRET detected photons in the 30 MeV-30 GeV energy range, with effective area roughly proportional to between 30 MeV and 200 MeV, and approximately energy independent ( cm) at higher energy (see Thompson et al. 1993). This area is similar to the LAT effective area at  MeV and smaller by roughly an order of magnitude than the LAT effective area at  GeV. From table 2.1 and fig. 2.3 of González Sánchez (2005), EGRET’s non-detections imply upper limits on the ratio of the EGRET fluence to the 20 keV–1 MeV BATSE fluence of % (consistent with Ando et al. 2008) for the brightest available bursts (50-300 keV BATSE fluence  erg/cm), and much weaker, , for dimmer bursts.

The roughly linear dependence of EGRET’s effective area between 30 MeV and 200 MeV, and the energy independent area at higher energy, implies that EGRET’s flux sensitivity is roughly energy independent between 30 MeV and 200 MeV, and falling at higher energy. Combined with the fact that the upper limits reported in González Sánchez (2005) were obtained assuming a spectrum, these upper limits apply to the 30 MeV–200 MeV fluence (the constraint implied on the fluence at higher energy is weaker and depends on the assumed spectrum). The upper limits derived in § 3 using LAT non-detections on the 0.1–1 GeV fluence are similar to those obtained by EGRET on the 30 MeV–200 MeV fluence. We obtained for the brightest % of the bursts, and % for the brightest in the sample (GRB081207 and GRB090829A), see fig. 2.

5 Summary and discussion

We have shown that the LGRB LF inferred from the sample of bursts detected by Fermi’s GBM is consistent with those determined by BATSE and Swift, see table 1, and that the GBM samples this LF in a manner similar to that of BATSE & Swift, see figure 1. We have derived the upper limits implied by the LAT non-detections on the ratio of the 100 MeV to 1 MeV fluences, for  MeV, during the prompt emission. The upper limits on obtained assuming at  MeV (see fig. 2), also imply upper limits on the 0.1–1 GeV fluence, which is approximately given by (the upper limit on the 1–10 GeV fluence is few times higher and depends on the assumed spectrum), and on the ratio of the 0.1–1 GeV fluence and the 0.1–1 MeV fluence, which is . The upper limits on are more stringent for brighter bursts (see fig. 2), with for of the bursts (see fig. 4). This implies that for most bursts the prompt  GeV emission may be comparable to the  MeV emission, but can not dominate it. For several bright bursts with reliable determination of the photon spectral index at  MeV, the LAT non detection implies an upper limit to the  MeV flux which is of the flux obtained by extrapolating the  MeV flux to high energy (see fig. 5). Examining figs. 2 and 4, we conclude that the ratio is not universal among GRBs. The detections and non-detection upper limits imply a spread in over at least an order of magnitude. The upper limits we obtain are similar to those inferred for the fluence at lower energy, 30–200 MeV, from EGRET’s non-detections of BATSE bursts (see § 4).

The upper limits on provide constraints on models for the prompt GRB emission. Models where the prompt  MeV emission is produced by inverse-Compton scattering of optical synchrotron photons (e.g. Stern & Poutanen 2004, Panaitescu & Kumar 2007), typically predict . This is not supported by the data. Such models are not necessarily ruled out by the current data, as they might be modified to include a suppression of the  GeV flux by pair production. Such modification may be required for all (widely discussed) models, in which the  MeV power-law photon spectrum reflects the power-law energy distribution of fast cooling electrons. The suppression of the  MeV flux, compared to that expected from an extrapolation of the  MeV power-law spectrum, suggests that either the electron energy distribution does not follow a power-law over a wide energy range, or that the high energy photons are absorbed, probably by pair production. Requiring an optical depth of at  MeV sets an upper limit to the expansion Lorentz factor (e.g. eq. 7 of Waxman 2003). Significant compactness of the emission region has been suggested by several authors (e.g. Guetta et al. 2001, Pe’er & Waxman 2004). The spectrum is modified in this case, compared to the optically thin case, with 100 MeV to 1 MeV flux ratios in the range obtained for typical parameters (e.g. figs. 8 & 11 of Pe’er & Waxman 2004).

Acknowledgements.
This research was supported in part by ISF, AEC and Minerva grants. DG & EP thank the Benoziyo center for Astrophysics at the Weizmann institute for hospitality during the time at which this research was initiated. We thank Nicola Omodei, David Coward for their useful advices.
GRB10 Fluence11 PF12 Band13 Function14 15  16  17  18 LAT19 (1 MeV)20 (100 MeV)21  22
(s) ( erg cm) (ph s cm) (keV) (keV) (deg) (erg s cm) (erg s cm)
080810 122.0 6.90e+00 1.85e+00 50 300 PL+HEC 313.5 -0.91 -1000 61 0 1.48e-08 0 3.35
080812 15.0 -1 -1 * * PL+HEC 140.0 0.17 -1000 71 0 0 0 -1
080816A 70.0 1.86e+01 3.48e+00 50 300 PL+HEC 146.7 -0.57 -1000 55 0 6.70e-10 0 -1
080816B 5.0 -1 1.38e+00 25 1000 PL+HEC 1230.0 -0.37 -1000 70 0 0 0 -1
080817A 70.0 -1 -1 * * * -1 1000.00 -1000 80 0 0 0 -1
080817B 6.0 2.60e+00 -1 25 1000 SPL -1 -17 -1000 68 0 4.16e-07 0 -1
080818A 50.0 2.26e+00 -1 50 300 SPL -1 -1.57 -1000 68 0 0 0 -1
080818B 10.0 1.00e+00 -1 50 300 PL+HEC 80.0 -1.30 -1000 68 0 1.26e-10 0 -1
080823 46.0 4.10e+00 -1 50 300 PL+HEC 164.7 -1.20 -1000 77 0 4.06e-09 0 -1
080824 28.0 2.30e+00 -1 50 300 Band 100.0 -0.40 -2.10 17 0 3.92e-08 2.47e-08 -1
080825C 22.0 2.40e+01 -1 50 300 Band 155.0 -0.39 -2.34 60 1 3.99e-07 8.34e-08 -1
080830 45.0 4.60e+00 -1 50 300 Band 154.0 -0.59 -1.69 23 0 1.13e-07 4.69e-07 -1
080904 22.0 2.25e+00 3.50e+00 50 300 Band 35.0 0.00 -2.70 23 0 1.29e-08 5.13e-10 -1
080905B 159.0 4.10e-02 2.10e-01 20 1000 SPL -1 -1.75 -1000 82 0 1.03e-10 0 2.37
080905C 28.0 4.60e+00 4.40e+00 25 1000 PL+HEC 78.8 -0.90 -1000 108 0 3.63e-12 0 -1
080906B 5.0 1.09e+01 2.20e+01 25 1000 Band 125.3 -0.07 -2.10 32 0 6.17e-07 3.89e-07 -1
080912 17.0 3.30e+00 4.10e+00 25 1000 SPL -1 -1.74 -1000 56 0 8.18e-08 0 -1
080913B 140.0 2.20e+00 -1 50 300 PL+HEC 114.0 -0.69 -1000 71 0 3.19e-11 0 -1
080916A 60.0 1.50e+01 4.50e+00 25 1000 PL+HEC 109.0 -0.90 -1000 76 0 1.70e-10 0 0.69
080916C 100.9 2.40e+02 6.87e+00 10 10000 Band 566.0 -0.92 -2.28 48 1 5.77e-07 1.59e-07 4.2
080920 85.0 2.40e+00 1.29e+00 25 1000 SPL -1 -1.42 -1000 16 0 1.86e-08 0 -1
080925 29.0 9.70e+00 -1 50 300 Band 120.0 -0.53 -2.26 38 0 1.24e-07 3.74e-08 -1
080927 25.0 5.70e+00 2.00e+00 25 1000 SPL -1 -1.50 -1000 75 0 1.57e-07 0 -1
080928 87.0 1.50e+00 -1 50 300 SPL -1 -1.80 -1000 -1 0 0 0 1.69
081003C 67.0 5.40e+00 -1 50 300 SPL -1 -1.41 -1000 48 0 1.48e-07 0 -1
081006A 7.0 7.10e-01 -1 50 300 Band 1135.0 -0.77 -1.80 16 0 2.54e-07 6.37e-07 -1
081006B 9.0 7.30e-01 -1 50 300 SPL -1 -1.30 -1000 3 0 1.85e-07 0 -1
081007A 12.0 1.20e+00 2.20e+00 25 900 SPL -1 -2.10 -1000 116 0 3.72e-08 0 0.53
081009 13.0 8.30e+00 -1 8 1000 Band 20.7 0.20 -4.00 67 0 2.53e-10 2.53e-14 -1
081012 30.0 3.80e+00 2.00e+00 25 900 PL+HEC 360.0 -0.31 -1000 61 0 5.44e-08 0 -1
081021 25.0 5.30e+00 4.20e+00 10 1000 Band 117.0 0.11 -2.80 125 0 2.55e-08 6.42e-10 -1
081024C 65.0 4.00e+00 1.00e+00 50 300 Band 65.0 -0.60 -2.50 78 0 1.21e-08 1.21e-09 -1
081025 45.0 7.10e+00 4.50e+00 8 1000 Band 200.0 0.15 -2.05 -1 0 9.87e-08 7.84e-08 -1
081028B 20.0 2.00e+00 6.90e+00 10 1000 PL+HEC 70.0 -0.55 -1000 107 0 1.63e-14 0 -1
Table 2: GBM parameters for the bursts detected by Fermi.
GRB Fluence PF Band Function       LAT (1 MeV) (100 MeV)  
(s) ( erg cm) (ph s cm) (keV) (keV) (deg) (erg s cm) (erg s cm)
081101B 8.0 1.60e+01 1.03e+01 8 1000 PL+HEC 550.0 -0.62 -1000 116 0 7.99e-07 0 -1
081102A 88.0 2.10e+00 -1 50 300 Band 72.0 0.44 -2.36 -1 0 1.16e-08 2.22e-09 3.04
081102B 2.2 1.12e+00 3.68e+00 8 1000 SPL -1 -17 -1000 53 0 1.03e-06 0 -1
081107 2.2 1.64e+00 1.10e+01 8 1000 Band 65.0 0.25 -2.80 52 0 5.04e-08 1.27e-09 -1
081109A 45.0 6.53e+00 3.20e+00 8 1000 PL+HEC 240.0 -1.28 -1000 -1 0 1.92e-08 0 -1
081110 20.0 -1 -1 8 1000 * -1 1000.00 -1000 67 0 0 0 -1
081118B 20.0 1.12e-01 6.70e-01 8 1000 Band 41.2 0.80 -2.14 41 0 7.07e-10 3.71e-10 -1
081120 12.0 2.70e+00 5.10e+00 8 1000 Band 44.0 0.40 -2.18 84 0 5.05e-08 2.20e-08 -1
081122A 26.0 9.60e+00 3.00e+01 8 1000 Band 158.6 -0.63 -2.24 21 0 8.14e-08 2.69e-08 -1
081124 35.0 9.50e-02 6.70e-01 8 1000 Band 22.8 -0.60 -2.83 86 0 7.57e-11 1.66e-12 -1
081125 15.0 4.91e+01 2.70e+01 8 1000 Band 221.0 0.14 -2.34 126 0 9.23e-07 1.93e-07 -1
081129 59.0 2.00e+01 1.40e+01 8 1000 Band 150.0 -0.50 -1.84 118 0 1.31e-07 2.73e-07 -1
081130B 12.0 1.30e+00 1.80e+00 50 300 PL+HEC 152.0 -0.77 -1000 66 0 1.10e-09 0 -1
081204C 4.7 1.48e+00 7.20e+00 8 1000 SPL -1 -1.40 -1000 56 0 3.03e-07 0 -1
081206A 24.0 4.00e+00 2.40e+00 8 1000 Band 151.0 0.13 -2.20 102 0 4.88e-08 1.94e-08 -1
081206B 10.0 -1 -1 * * * -1 1000.00 -1000 82 0 0 0 -1
081206C 20.0 1.19e+00 7.60e-01 50 300 SPL -1 -1.35 -1000 71 0 0 0 -1
081207 153.0 1.06e+02 -1 10 1000 Band 639.0 -0.65 -2.41 56 0 8.91e-07 1.35e-07 -1
081215A 7.7 5.44e+01 6.89e+01 8 1000 Band 304.0 -0.58 -2.07 86 1 1.31e-06 9.69e-07 -1
081215B 90.0 2.80e+00 -1 50 300 PL+HEC 139.0 -0.14 -1000 112 0 8.24e-11 0 -1
081217 39.0 1.00e+01 4.00e+00 8 1000 Band 167.0 -0.61 -2.70 54 0 7.20e-08 2.87e-09 -1
081221 40.0 3.70e+01 3.30e+01 8 1000 Band 77.0 -0.42 -2.91 78 0 4.87e-08 7.37e-10 -1
081222 30.0 1.35e+01 1.48e+01 8 1000 Band 134.0 -0.55 -2.10 50 0 3.08e-07 1.94e-07 2.77
081224 50.0 -1 -1 * * * -1 1000.00 -1000 16 0 0 0 -1
081225 42.0 2.45e+00 6.00e-01 50 300 SPL -1 -1.51 -1000 55 0 0 0 -1
081226C 60.0 2.32e+00 4.50e+00 8 1000 PL+HEC 82.0 -14 -1000 54 0 1.54e-11 0 -1
081231 29.0 1.20e+01 1.53e+00 8 1000 Band 152.3 -0.80 -2.03 20 0 8.25e-08 7.19e-08 -1
090107B 24.1 1.75e+00 3.68e+00 8 1000 PL+HEC 106.1 -0.68 -1000 -1 0 9.11e-12 0 -1
090109 5.0 1.21e+00 2.76e+00 8 1000 SPL -1 -1.50 -1000 62 0 1.62e-07 0 -1
090112A 65.0 5.20e+00 7.00e+00 8 1000 Band 150.0 -0.94 -2.01 4 0 6.23e-08 5.95e-08 -1
090112B 12.0 5.40e+00 1.40e+01 8 1000 Band 139.0 -0.75 -2.43 95 0 1.01e-07 1.39e-08 -1
090117A 21.0 1.80e+00 9.60e+00 8 1000 Band 25.0 -0.40 -2.50 51 0 1.26e-08 1.26e-09 -1
090117B 27.0 2.10e+00 4.60e+00 8 1000 SPL -1 -1.55 -1000 49 0 3.95e-08 0 -1
090117C 86.0 1.10e+01 4.20e+00 8 1000 Band 247.0 -1 -2.10 54 0 1.05e-07 6.65e-08 -1
GRB Fluence PF Band Function       LAT (1 MeV) (100 MeV)  
(s) ( erg cm) (ph s cm) (keV) (keV) (deg) (erg s cm) (erg s cm)
090126B 10.8 1.25e+00 4.90e+00 8 1000 PL+HEC 47.5 -0.99 -1000 18 0 1.85e-15 0 -1
090129 17.2 5.60e+00 8.00e+00 8 1000 Band 123.2 -1.39 -1.98 22 0 9.45e-08 1.04e-07 -1
090131 36.4 2.23e+01 4.79e+01 8 1000 Band 58.4 -1.27 -2.26 40 0 7.33e-08 2.21e-08 -1
090202 66.0 8.65e+00 7.77e+00 8 1000 PL+HEC 570.0 -1.31 -1000 55 0 1.66e-07 0 -1
090207 10.0 4.01e+00 1.88e+00 8 1000 SPL -1 -1.59 -1000 45 0 1.10e-07 0 -1
090217 32.8 3.08e+01 1.12e+01 8 1000 Band 610.0 -0.85 -2.86 34 1 6.62e-07 9.74e-09 -1
090222 18.0 2.19e+00 1.10e+00 8 1000 Band 147.9 -0.97 -2.56 80 0 1.71e-08 1.30e-09 -1
090227A 50.0 9.00e+00 4.57e+00 8 1000 Band 1357.0 -0.92 -3.60 21 0 4.00e-07 4.30e-10 -1
090228B 7.2 9.96e-01 2.53e+00 8 1000 PL+HEC 147.8 -0.70 -1000 20 0 4.01e-10 0 -1
090301B 28.0 2.69e+00 4.40e+00 8 1000 Band 427.0 -0.98 -1.93 56 0 2.21e-07 3.05e-07 -1
090306C 38.8 9.00e-01 2.40e+00 8 1000 Band 87.0 -0.32 -2.28 14 0 1.52e-08 4.19e-09 -1
090307B 30.0 1.70e+00 1.80e+00 8 1000 PL+HEC 212.0 -0.70 -1000 83 0 2.71e-09 0 -1
090308B 2.1 3.46e+00 1.42e+01 8 1000 PL+HEC 710.3 -0.54 -1000 50 0 1.06e-06 0 -1
090309B 60.0 4.70e+00 4.43e+00 8 1000 PL+HEC 197.0 -1.52 -1000 26 0 1.38e-08 0 -1
090310 125.2 2.15e+00 4.40e+00 8 1000 PL+HEC 279.0 -0.65 -1000 77 0 4.02e-08 0 -1
090319 67.7 7.47e+00 3.85e+00 8 1000 PL+HEC 187.3 0.90 -1000 27 0 4.95e-11 0 -1
090320A 10.0 -1 -1 8 1000 * -1 1000.00 -1000 60 0 0 0 -1
090320B 52.0 1.10e+00 1.20e-01 8 1000 PL+HEC 72.0 -1.10 -1000 101 0 7.16e-13 0 -1
090320C 4.0 -1 -1 8 1000 * -1 1000.00 -1000 40 0 0 0 -1
090323 70.0 1.00e+02 1.23e+01 8 1000 PL+HEC 697.0 -0.89 -1000 -1 1 6.46e-07 0 3.57
090326 11.2 8.60e-01 -1 8 1000 PL+HEC 75.0 -0.86 -1000 103 0 4.17e-13 0 -1
090327 24.0 3.00e+00 3.50e+00 8 1000 Band 89.7 -0.39 -2.90 66 0 1.09e-08 1.72e-10 -1
090328A 100.0 8.09e+01 1.85e+01 8 1000 Band 653.0 -0.93 -2.20 -1 1 1.40e-06 5.57e-07 0.74
090330 80.0 1.14e+01 6.80e+00 8 1000 Band 246.0 -0.99 -2.68 50 0 7.45e-08 3.25e-09 -1
090403 16.0 -1 -1 * * * -1 1000.00 -1000 42 0 0 0 -1
090409 20.0 6.14e-01 1.36e+00 8 1000 PL+HEC 137.0 1.20 -1000 90 0 8.53e-14 0 -1
090411A 24.6 8.60e+00 3.25e+00 8 1000 Band 141.0 -0.88 -1.82 59 0 1.57e-07 3.60e-07 -1
090411B 18.7 8.00e+00 7.40e+00 8 1000 Band 189.0 -0.80 -2.00 111 0 1.09e-07 1.09e-07 -1
090422 10.0 1.00e+00 7.80e+00 8 1000 SPL -1 1.81 -1000 29 0 2.89e-07 0 -1
090423 12.0 1.10e+00 3.30e+00 8 1000 PL+HEC 82.0 -0.77 -1000 75.6 0 8.96e-13 0 8.10
090424 52.0 5.20e+01 1.37e+02 8 1000 Band 177.0 0.90 -2.90 71 0 1.13e-07 1.79e-09 0.54
090425 72.0 1.30e+01 1.40e+01 8 1000 Band 69.0 -1.29 -2.03 105 0 1.28e-07 1.12e-07 -1
090426B 3.8 5.20e-01 -1 8 1000 SPL -1 -1.60 -1000 56 0 4.75e-08 0 -1
090426C 12.0 3.10e+00 6.80e+00 8 1000 Band 295.0 -1.29 -1.98 69 0 9.65e-08 1.06e-07 -1
GRB Fluence PF Band Function       LAT (1 MeV) (100 MeV)  
(s) ( erg cm) (ph s cm) (keV) (keV) (deg) (erg s cm) (erg s cm)
090427B 7.0 8.00e-01 -1 8 1000 SPL -1 -1.10 -1000 14 0 1.19e-07 0 -1
090427C 12.5 1.60e+00 -1 8 1000 PL+HEC 75.0 0.35 -1000 81 0 7.59e-18 0 -1
090428A 8.0 9.90e-01 1.23e+01 8 1000 Band 85.0 -0.40 -2.70 96 0 3.13e-08 1.25e-09 -1
090428B 30.0 5.20e+00 1.01e+01 8 1000 Band 53.0 -1.81 -2.17 101 0 3.25e-08 1.49e-08 -1
090429C 13.0 3.70e+00 6.70e+00 8 1000 SPL -1 -1.43 -1000 112 0 1.73e-07 0 -1
090429D 11.0 1.60e+00 8.60e-01 8 1000 SPL 223.0 -0.87 -1000 33 0 1.27e-07 0 -1
090502 66.2 3.50e-02 6.20e+00 8 1000 PL+HEC 63.2 -1.10 -1000 77 0 3.68e-15 0 -1
090509 295.0 8.40e+00 3.10e+00 8 1000 SPL -1 -1.55 -1000 75 0 2.18e-10 0 -1
090510B 7.0 -1 -1 * * * -1 1000.00 -1000 100 0 0 0 -1
090511 14.0 1.80e+00 2.50e+00 8 1000 PL+HEC 391.0 -0.95 -1000 67 0 4.26e-08 0 -1
090513A 23.0 6.80e+00 2.70e+00 8 1000 PL+HEC 850.0 -0.90 -1000 89 0 1.91e-07 0 -1
090514 49.0 8.10e+00 7.60e+00 8 1000 SPL -1 -1.92 -1000 19 0 3.47e-08 0 -1
090516A 350.0 2.30e+01 5.30e+00 8 1000 Band 51.4 -13 -2.10 20 0 1.49e-08 9.41e-09 4.11
090516B 350.0 3.00e+01 4.00e+00 8 1000 PL+HEC 327.0 -11 -1000 45 0 3.38e-08 0 -1
090516C 15.0 4.00e+00 7.70e+00 8 1000 Band 38.0 -0.44 -1.81 69 0 8.74e-08 2.10e-07 -1
090518A 9.0 1.60e+00 4.70e+00 8 1000 SPL -1 -1.59 -1000 53 0 8.38e-08 0 -1
090518B 12.0 2.20e+00 5.60e+00 8 1000 PL+HEC 127.0 -0.74 -1000 90 0 3.00e-10 0 -1
090519B 87.0 1.40e+00 5.02e+00 8 1000 SPL -1 -1.63 -1000 18 0 1.74e-07 0 -1
090520C 4.9 3.54e+00 4.47e+00 8 1000 Band 204.2 -0.73 -1.96 71 0 2.75e-07 3.31e-07 -1
090520D 12.0 4.00e+00 4.10e+00 8 1000 Band 46.3 -0.99 -3.25 66 0 3.32e-09 1.05e-11 -1
090522 22.0 1.20e+00 3.50e+00 8 1000 PL+HEC 75.8 -13 -1000 53 0 1.97e-12 0 -1
090524 72.0 1.85e+01 1.41e+01 8 1000 Band 82.6 -1 -2.30 63 0 3.86e-08 9.70e-09 -1
090528A 68.0 9.30e+00 7.60e+00 8 1000 PL+HEC 99.0 -1.70 -1000 81 0 9.53e-09 0 -1
090528B 102.0 4.65e+01 1.47e+01 8 1000 Band 172.0 -1.10 -2.30 65 0 1.56e-07 3.91e-08 -1
090529B 5.1 3.40e-01 4.10e+00 8 1000 Band 142.0 -0.70 -2.00 36 0 1.42e-08 1.42e-08 -1
090529C 10.4 3.10e+00 2.50e+01 8 1000 Band 188.0 -0.84 -2.10 69 0 8.64e-08 5.45e-08 -1
090530B 194.0 5.90e+01 1.08e+01 8 1000 Band 67.0 -0.71 -2.42 84 0 5.92e-08 8.55e-09 -1
090602 16.0 5.70e+00 3.62e+00 8 1000 PL+HEC 503.0 -0.56 -1000 112 0 1.84e-07 0 -1
090606 60.0 3.19e+00 2.41e+00 8 1000 SPL -1 -1.63 -1000 128 0 8.15e-08 0 -1
090608 61.0 3.20e+00 2.70e+00 8 1000 SPL -1 -1.83 -1000 93 0 2.50e-08 0 -1
090610A 6.5 7.32e-01 9.40e-01 8 1000 SPL -1 -1.30 -1000 70 0 8.42e-08 0 -1
090610B 202.5 4.13e+00 1.54e+00 8 1000 SPL -1 -1.66 -1000 91 0 8.41e-10 0 -1
090610C 18.1 8.54e-01 1.12e+00 8 1000 SPL -1 -1.62 -1000 104 0 3.14e-08 0 -1
090612 58.0 2.37e+00 1.63e+00 8 1000 Band 357.0 -0.60 -1.90 56 0 1.75e-07 2.78e-07 -1
GRB Fluence PF Band Function     LAT (1 MeV) (100 MeV)  
(s) ( erg cm) (ph s cm) (keV) (keV) (deg) (erg s cm) (erg s cm)
090616 2.7 2.23e-01 2.08e+00 8 1000 SPL -1 -1.27 -1000 68 0 2.62e-07 0 -1
090618 155.0 2.70e+02 7.34e+01 8 1000 Band 155.5 -1.26 -2.50 133 0 2.75e-07 2.75e-08 0.54
090620 16.5 6.60e+00 7.00e+00 8 1000 Band 156.0 -0.40 -2.44 60 0 7.19e-08 9.48e-09 -1
090621A 294.0 4.40e+00 1.92e+00 8 1000 Band 56.0 -1.10 -2.12 12 0 1.59e-08 9.15e-09 -1
090621C 59.9 1.80e+00 2.29e+00 8 1000 PL+HEC 148.0 -1.40 -1000 52 0 1.79e-09 0 -1
090621D 39.9 1.34e+00 1.74e+00 8 1000 SPL -1 -1.66 -1000 79 0 2.63e-08 0 -1
090623 72.2 9.60e+00 3.30e+00 8 1000 Band 428.0 -0.69 -2.30 73 0 8.35e-08 2.10e-08 -1
090625A 51.0 8.80e-01 5.00e-01 8 1000 PL+HEC 198.0 -0.60 -1000 13 0 7.18e-10 0 -1
090625B 13.6 1.04e+00 1.87e+00 8 1000 Band 100.0 -0.40 -2.00 125 0 3.62e-08 3.62e-08 -1
090626 70.0 3.50e+01 1.79e+01 8 1000 Band 175.0 -1.29 -1.98 15 1 1.43e-07 1.57e-07 -1
090630 5.1 5.10e-01 2.78e+00 8 1000 Band 71.0 -1.50 -2.30 75 0 1.32e-08 3.30e-09 -1
090701 12.0 4.50e-01 2.10e+00 8 1000 SPL -1 1.84 -1000 13 0 1.44e-07 0 -1
090703 9.0 6.80e-01 1.00e+00 8 1000 SPL -1 -1.72 -1000 25 0 2.76e-08 0 -1
090704 70.0 5.80e+00 1.20e+00 8 1000 PL+HEC 233.7 -1.13 -1000 77 0 6.15e-09 0 -1
090706 100.0 1.50e+00 1.24e+00 8 1000 SPL -1 -2.16 -1000 20 0 4.90e-09 0 -1
090708 18.0 4.00e-01 1.00e+00 8 1000 PL+HEC 47.5 -1.29 -1000 55 0 4.90e-14 0 -1
090709B 32.0 1.30e+00 2.00e+00 8 1000 PL+HEC 130.0 -11 -1000 35 0 1.71e-10 0 -1
090711 100.0 1.17e+01 4.20e+00 8 1000 PL+HEC 210.0 -1.30 -1000 13 0 8.06e-09 0 -1
090712 72.0 4.20e+00 6.30e-01 8 1000 PL+HEC 505.0 -0.68 -1000 33 0 1.96e-08 0 -1
090713 113.0 3.70e+00 1.60e+00 8 1000 PL+HEC 99.0 -0.34 -1000 63 0 3.98e-13 0 -1
090717A 70.0 4.50e-01 7.80e+00 8 1000 Band 120.0 -0.88 -2.33 70 0 4.66e-09 1.02e-09 -1
090718B 28.0 2.52e+01 3.20e+01 8 1000 Band 184.0 -1.18 -2.59 76 0 1.24e-07 8.19e-09 -1
090719 16.0 4.83e+01 3.78e+01 8 1000 Band 254.0 -0.68 -2.92 88 0 4.55e-07 6.57e-09 -1
090720A 7.0 2.90e+00 1.09e+01 8 1000 PL+HEC 117.5 -0.75 -1000 113 0 2.14e-10 0 -1
090720B 20.0 1.06e+01 1.09e+01 8 1000 Band 924.0 -1 -2.43 56 0 2.96e-07 3.97e-08 -1
090807B 3.0 1.02e+00 1.09e+01 8 1000 Band 37.0 -0.60 -2.40 45 0 4.65e-08 7.38e-09 -1
090809B 15.0 2.26e+01 2.36e+01 8 1000 Band 198.0 -0.85 -2.02 81 0 4.95e-07 4.51e-07 -1
090813 9.0 3.50e+00 1.44e+01 8 1000 Band 95.0 -1.25 -2.00 35.3 0 9.45e-08 9.45e-08 -1
090815A 200.0 3.40e+00 1.90e+00 8 1000 SPL -1 -1.50 -1000 87 0 6.29e-08 0 -1
090815B 30.0 5.05e+00 1.44e+01 8 1000 Band 18.6 -1.82 -2.70 82 0 6.71e-09 2.67e-10 -1
090817 220.0 7.30e+00 3.80e+00 8 1000 Band 115.0 -1.10 -2.20 82 0 6.47e-09 2.58e-09 -1
090820A 60.0 6.60e+01 5.80e+01 8 1000 Band 215.0 -0.69 -2.61 108 0 3.64e-07 2.19e-08 -1
GRB Fluence PF Band Function     LAT (1 MeV) (100 MeV)  
(s) ( erg cm) (ph s cm) (keV) (keV) (deg) (erg s cm) (erg s cm)
090820B 11.2 1.16e+00 6.10e+00 8 1000 PL+HEC 38.8 -1.44 -1000 32 0 2.10e-13 0 -1
090826 8.5 1.26e+00 3.28e+00 8 1000 PL+HEC 172.0 -0.96 -1000 35 0 1.55e-09 0 -1
090828 100.0 2.52e+01 1.62e+01 8 1000 Band 136.5 -1.23 -2.12 95 0 5.50e-08 3.16e-08 -1
090829A 85.0 1.02e+02 5.15e+01 8 1000 Band 183.0 -1.44 -2.10 47 0 2.44e-07 1.54e-07 -1
090829B 100.0 6.40e+00 3.20e+00 8 1000 Band 143.0 -0.70 -2.40 42 0 3.39e-08 5.38e-09 -1
090831 69.1 1.66e+01 9.40e+00 8 1000 Band 243.8 -1.52 -1.96 107 0 9.92e-08 1.19e-07 -1
090902B 21.0 3.74e+02 4.61e+01 50 10000 Band 798.0 -0.61 -3.87 52 1 7.16e-06 8.88e-10 1.82
090904B 71.0 2.44e+01 9.80e+00 8 1000 Band 106.3 -1.26 -2.18 113 0 6.20e-08 2.71e-08 -1
090910 62.0 9.20e+00 2.30e+00 8 1000 Band 274.8 -0.90 -2.00 107 0 6.32e-08 6.32e-08 -1
090922A 92.0 1.14e+01 1.56e+01 8 1000 Band 139.3 -0.77 -2.28 19 0 2.22e-07 6.11e-08 -1
090925 50.0 9.46e+00 4.20e+00 8 1000 Band 156.0 -0.60 -1.91 116 0 1.59e-07 2.41e-07 -1
090926A 20.0 1.45e+02 8.08e+01 8 1000 Band 268.0 -0.69 -2.34 52 1 1.85e-06 3.84e-07 2.11
090926B 81.0 8.70e+00 -1 10 1000 PL+HEC 91.0 -0.13 -1000 100 0 6.54e-14 0 1.24
090929A 8.5 1.06e+01 1.09e+01 8 1000 PL+HEC 610.9 -0.52 -1000 122 0 9.81e-07 0 -1
091003A 21.1 3.76e+01 3.18e+01 8 1000 Band 486.2 -1.13 -2.64 13 1 4.93e-07 2.59e-08 0.90
091010 8.1 1.09e+01 4.09e+01 8 1000 PL+HEC 150.0 -1.11 -1000 55.7 0 1.72e-08 0 -1
091020 37.0 1.00e+01 7.40e+00 8 1000 Band 47.9 0.20 -1.70 118 0 1.47e-07 5.84e-07 1.71
091024 1080.0 -1 -1 * * * 400.0 1000.00 -1000 14 0 0 0 1.09
091030 160.0 3.03e+01 9.58e+00 8 1000 Band 507.0 -0.88 -2.20 100 0 2.92e-07 1.16e-07 -1
091031 35.0 2.05e+01 7.50e+00 8 1000 Band 503.1 -0.91 -2.34 22 1 2.09e-07 4.36e-08 -1
091102A 7.3 2.10e+00 2.90e+00 8 1000 SPL -1 -1.24 -1000 94 0 3.20e-07 0 -1
091112 40.0 9.70e+00 -1 10 1000 PL+HEC 750.0 -1.13 -1000 82 0 1.80e-07 0 -1
091120 52.0 3.02e+01 2.13e+01 8 1000 Band 124.0 -1.15 -2.98 45 0 3.50e-08 3.83e-10 -1
091123 650.0 4.07e+01 6.10e+00 8 1000 PL+HEC 101.3 -18 -1000 106 0 5.65e-11 0 -1
091127 9.0 1.87e+01 4.69e+01 8 1000 Band 36.0 -1.27 -2.20 25 0 2.64e-07 1.05e-07 0.49
091128 97.0 3.76e+01 9.30e+00 8 1000 Band 177.4 -0.99 -3.90 96 0 1.83e-08 2.89e-12 -1
091208B 15.0 5.80e+00 3.24e+01 8 1000 Band 124.0 -1.44 -2.32 56 0 6.13e-08 1.40e-08 1.06
091221 32.0 1.38e+01 5.10e+00 8 1000 Band 207.0 -0.69 -2.30 53 0 1.03e-07 2.59e-08 -1
090530B 194.0 5.90e+01 1.08e+01 8 1000 Band 67.0 -0.71 -2.42 84 0 5.92e-08 8.55e-09 -1
GRB Fluence PF Band Function     LAT (1 MeV) (100 MeV)  
(s) ( erg cm) (ph s cm) (keV) (keV) (deg) (erg s cm) (erg s cm)
100111A 12.0 1.50e+00 3.50e+00 8 1000 SPL -1 -1.66 -1000 32 0 7.71e-08 0 -1
100116A 110.0 3.36e+01 -1 8 10000 PL+HEC 1240.0 -12 -1000 29 1 6.39e-10 0 -1
100122A 6.6 1.00e+01 1.04e+01 8 1000 Band 45.6 -0.98 -2.31 45 0 4.18e-08 1.00e-08 -1
100130A 106.0 8.21e+00 5.90e+00 8 1000 PL+HEC 100.5 -0.97 -1000 51 0 3.36e-11 0 -1
100130B 90.0 1.34e+01 3.72e+00 8 1000 PL+HEC 208.0 -1.22 -1000 89 0 7.89e-09 0 -1
100131A 6.2 7.72e+00 3.38e+01 8 1000 Band 132.1 -0.63 -2.21 27 0 3.79e-07 1.44e-07 -1
100205B 13.6 1.41e+00 2.98e+00 8 1000 PL+HEC 124.2 -0.47 -1000 102 0 4.12e-11 0 -1
100212A 2.3 3.81e-01 3.16e+00 8 1000 PL+HEC 159.3 -1.15 -1000 15 0 9.60e-09 0 -1
100218A 30.8 2.58e+00 1.40e+00 8 1000 Band 131.6 -0.14 -2.00 37 0 2.50e-08 2.50e-08 -1
23

Footnotes

  1. See Swift information page
    http://Swift.gsfc.nasa.gov/docs/Swift/archive/grb_table.html
  2. Best fit values and their 1  uncertainty range.
  3. footnotemark:

  4. footnotetext: Integrated over .
    footnotetext: obtained for best fit values.
  5. footnotetext: Integrated over .
  6. footnotetext: obtained for best fit values.
  7. Some GRBs have reported fluence and no reported peak flux. While these GRBs were excluded from the peak flux analysis described in § 2, they have been included in the fluence ratio analysis.
  8. For 4 GRBs with multi-peak structure, separate sets of spectral fit parameters are reported in the literature for each pulse (GRBs 081009, 090509, 090516A, 090610B). In these cases, we have determined the 1 MeV fluence using the spectrum of the second pulse (see Table 2), under the assumption that the bulk of the MeV-GeV output is emitted simultaneously with the second pulse. This is motivated by the 2 long GRBs with detailed published GBM and LAT light curves, GRB080916C (Abdo et al. 2009) and GRB090902B (Bissaldi et al. 2009).
  9. For GRBs with spectra fitted in the GBM band with single power-laws, the spectrum cannot be extrapolated straightforwardly to 1 MeV if the energy range used for the power-law fit is much softer. Thus, we have retained the GRBs fitted with single power-laws over an energy reaching or exceeding 800 keV, and excluded from the analsyis GRBs 080818A, 080928, 081206C, 081225.
  10. footnotemark:
  11. footnotemark:
  12. footnotemark:
  13. footnotemark:
  14. footnotemark:
  15. footnotemark:
  16. footnotemark:
  17. footnotemark:
  18. footnotemark:
  19. footnotemark:
  20. footnotemark:
  21. footnotemark:
  22. footnotemark:
  23. footnotetext: GRB name.
    footnotetext: The duration of the GRB.
    footnotetext: GRB fluence in the energy interval specified in Col. 5 (set to -1 when value is not available)
    footnotetext: GRB peak flux (set to -1 when value is not available)
    footnotetext: Energy band for the fluence determination
    footnotetext: Method used to fit the spectra (Band=broken power law, SPL=single power law, PL+HEC=power law and exponential cutoff)
    footnotetext: Peak energy (set to -1 when not available)
    footnotetext: The spectral index (set to 1000 when not available).
    footnotetext: The spectral index (set to -1000 when not available).
    footnotetext: The angle, , from the LAT boresight, in deg (set to -1 when not available)
    footnotetext: LAT detection (1 = YES, 0 = NO)
    footnotetext: The flux at MeV (set zero when not available).
    footnotetext: The flux at 100 MeV obtained by extrapolating to high energy the  MeV spectrum (set zero when not available).
    footnotetext: The redshift (equal to -1 if not measured)
  24. footnotetext: GRB name.
  25. footnotetext: The duration of the GRB.
  26. footnotetext: GRB fluence in the energy interval specified in Col. 5 (set to -1 when value is not available)
  27. footnotetext: GRB peak flux (set to -1 when value is not available)
  28. footnotetext: Energy band for the fluence determination
  29. footnotetext: Method used to fit the spectra (Band=broken power law, SPL=single power law, PL+HEC=power law and exponential cutoff)
  30. footnotetext: Peak energy (set to -1 when not available)
  31. footnotetext: The spectral index (set to 1000 when not available).
  32. footnotetext: The spectral index (set to -1000 when not available).
  33. footnotetext: The angle, , from the LAT boresight, in deg (set to -1 when not available)
  34. footnotetext: LAT detection (1 = YES, 0 = NO)
  35. footnotetext: The flux at MeV (set zero when not available).
  36. footnotetext: The flux at 100 MeV obtained by extrapolating to high energy the  MeV spectrum (set zero when not available).
  37. footnotetext: The redshift (equal to -1 if not measured)

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