J/ApJ/925/152 The 2nd AGILE MCAL GRB cat.: 13yr of observations (Ursi+, 2022)
The second AGILE MCAL Gamma-Ray Burst Catalog: 13 yr of Observations.
Ursi A., Romani M., Verrecchia F., Pittori C., Tavani M., Marisaldi M.,
Galli M., Labanti C., Parmiggiani N., Bulgarelli A., Addis A.,
Baroncelli L., Cardillo M., Casentini C., Cattaneo P.W., Chen A.,
Di Piano A., Fuschino F., Longo F., Lucarelli F., Morselli A., Piano G.,
Vercellone S.
<Astrophys. J., 925, 152 (2022)>
=2022ApJ...925..152U 2022ApJ...925..152U
ADC_Keywords: GRB
Keywords: Gamma-ray bursts
Abstract:
We present the results of a systematic search and analysis of GRBs
detected by the Astrorivelatore Gamma ad Immagini LEggero (AGILE)
MiniCALorimeter (MCAL; 0.4-100MeV) over a time frame of 13yr, from
2007 to 2020 November. The MCAL GRB sample consists of 503 bursts
triggered by MCAL, 394 of which were fully detected onboard with high
time resolution. The sample consists of about 44% short GRBs and 56%
long GRBs. In addition, 109 bursts triggered partial MCAL onboard data
acquisitions, providing further detections that can be used for joint
analyses or triangulations. More than 90% of these GRBs were also
detected by the AGILE Scientific RateMeters (RMs), providing
simultaneous observations between 20keV and 100MeV. We performed
spectral analysis of these events in the 0.4-50MeV energy range. We
could fit the time-integrated spectrum of 258 GRBs with a single
power-law model, resulting in a mean photon index <β> of-2.3.
Among them, 43 bursts could also be fitted with a Band model, with
peak energy above 400 keV, resulting in a mean low-energy photon index
<α≥-0.6, a mean high-energy photon index <β≥-2.5, and a
mean peak energy <Ep≥640keV. The AGILE MCAL GRB sample mostly
consists of hard-spectrum GRBs, with a large fraction of
short-duration events. We discuss properties and features of the MCAL
bursts, whose detections can be used to perform joint broad-band
analysis with other missions, and to provide insights on the
high-energy component of the prompt emission in the tens of mega
electron volt energy range.
Description:
The Astrorivelatore Gamma ad Immagini LEggero (AGILE) is an Italian
space mission devoted to high-energy astrophysics. The satellite
payload houses a suite of detectors that allow broad-band observation
of Galactic and extragalactic sources in the 20keV-50GeV energy range.
The AGILE MiniCALorimeter (MCAL) is a non-imaging gamma-ray
scintillation detector, sensitive in the 400keV-100MeV energy range.
See Section 2.1.
We analyzed the AGILE MCAL onboard triggers issued in the period from
2007 to 2020 November. This sample consisted of more than 106 trigger
acquisitions, resulting in a total effective exposure time of ∼100days.
See Section 3.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 90 503 List of the Ntot=503 GRBs triggered by
MiniCALorimeter (MCAL) and fully (Nfull=394) or
partially (Npartial=109) acquired by data
acquisitions
table3.dat 107 258 List of 258 localized GRBs whose time-integrated
full spectrum is fitted with a single power law
model in the 0.4-50MeV energy range
table4.dat 103 43 List of 43 localized GRBs whose time-integrated
full spectrum is fitted with a Band model with
Ep≤400keV in the 0.4-50MeV energy range
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See also:
J/ApJS/156/217 : IPN supplement to BATSE untriggered GRBs (Hurley+, 2005)
J/ApJS/191/179 : IPN supplement to the BeppoSAX GRB catalog (Hurley+, 2010)
J/ApJS/197/34 : The IPN supplement to the HETE-2 GRB catalog (Hurley+, 2011)
J/A+A/530/A21 : Spectral properties of 438 GRBs (Nava+, 2011)
J/A+A/553/A33 : AGILE Mini-Calorimeter γ-ray burst cat. (Galli+, 2013)
J/ApJS/207/39 : IPN supplement to the Fermi GBM (Hurley+, 2013)
J/ApJS/207/38 : IPN localizations of Konus short GRBs (Pal'shin+, 2013)
J/ApJS/223/28 : The third Fermi/GBM GRB catalog (6yr) (Bhat+, 2016)
J/ApJS/224/10 : The second Konus-Wind short GRB catalog (Svinkin+, 2016)
J/ApJ/913/60 : GRB energetics from Fermi-GBM 10years (Poolakkil+, 2021)
J/ApJS/259/34 : 2nd cat. of IPN localizations of short GRBs (Svinkin+, 2022)
http://www.ssl.berkeley.edu/ipn3/ : IPN3 home page
http://www.isdc.unige.ch/integral/science/grb : INTEGRAL GRBs home page
http://heasarc.gsfc.nasa.gov/W3Browse/ : Fermi and Swift triggers data
http://gcn.gsfc.nasa.gov/agile_mcal.html : AGILE MCAL Trigger Information
http://www.ssdc.asi.it/mcal2grbcat/ : The 2nd AGILE-MCAL GRB catalog
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 3 A3 --- C "GRB" if confirmed by other instruments (1)
4- 10 A7 --- GRB GRB identifier (YYMMDDA) (1)
12- 15 I4 yr Obs.Y [2007/2020] UTC Year of the trigger time
17- 18 I2 "month" Obs.M UTC Month of the trigger time
20- 21 I2 d Obs.D UTC Day of the trigger time
23- 24 I2 h Obs.h UTC Hour of the trigger time
26- 27 I2 min Obs.m UTC Minute of the trigger time
29- 33 F5.2 s Obs.s UTC Second of the trigger time
35- 36 A2 --- Conf Onboard configuration (C1-C4) (2)
38 A1 --- RM-SA SuperAGILE ratemeter detection? (3)
40 A1 --- RM-AC Anti-Coincidence (AC) scientific ratemeter
detection? (3)
42 A1 --- RM-MCAL AGILE MiniCALorimeter ratemeter detection? (3)
44 A1 --- MCAL AGILE MiniCALorimeter detection? (3)
46- 48 I3 Hz Bkg [139/856] Average background rate in MCAL
energy band
50- 53 A4 --- l_T50 [≥ ] Limit flag on T50
55- 61 F7.3 s T50 [0.007/128] The T50 time duration
63- 67 F5.3 s e_T50 [0.001/3] Uncertainty in T50
69 A1 --- f_T50 [*] Flag on T50 (4)
71- 74 A4 --- l_T90 [≥ ] Limit flag on T90
76- 82 F7.3 s T90 [0.012/213] The T90 time duration
84- 88 F5.3 s e_T90 [0.001/3] Uncertainty in T90
90 A1 --- f_T90 [*] Flag on T90 (4)
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Note (1): For each burst we report name; no GRB-prefix (in col. "C") means
candidate burst not confirmed by other instruments (27 occurrences).
Events with no "GRB" prefix do not have a match with IPN list and
are only retrieved in the AGILE/MiniCALorimeter (MCAL) data.
Note (2): In order to provide more homogeneous subsets of the MCAL GRBs, we
introduce a flag indicating different configurations, running in
different periods of the AGILE lifetime, during which the onboard
trigger condition and sensitivity to GRBs can be considered stable. In
particular, the configuration flag may assume the following values:
C1 = from 2007 April to 2009 November; the satellite was in its 2yr nominal
phase and fully operational, all passages were served at the ground
station, and all triggered GRBs were completely acquired onboard
C2 = from 2009 December to 2015 February; after the reaction wheel failure,
the satellite started spinning around its Sun-pointing axis, making
the detection of long-duration transients more difficult, and
requiring onboard configuration changes to test the detector
C3 = from 2015 March to 2016 August; the AC veto shield was inhibited to
increase the detection of submillisecond terrestrial gamma-ray flashes,
with the drawback effect of an enhancement of the background rate,
which required a change of the onboard configuration to make the
trigger logics more conservative
C4 = from 2016 August, alternating with C3, on demand; a new onboard
configuration was introduced, aimed at increasing the sensitivity to
short-duration, weak signals (e.g., subthreshold events or GRB
precursors), in view of the LIGO-Virgo follow-up campaign. Such
configuration is available on demand and it is adopted whenever
possible
Note (3): Code as follows:
Y = complete detection;
N = no detection;
I = incomplete acquisition;
F = fragmented acquisition;
n = no data.
Note (4): Flag as follows:
* = Evaluated on incomplete data acquisitions.
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 3 A3 --- C Always "GRB"
4- 10 A7 --- GRB GRB identifier (YYMMDDA)
12- 14 A3 --- Obs Localizing facility (1)
16- 21 F6.2 deg GLON Galactic longitude
23- 28 F6.2 deg GLAT [-86.45/88.45] Galactic latitude
30- 35 F6.2 deg theta [5.4/173] The θ angle of event observation
37- 42 F6.2 deg phi The φ angle of event observation
44- 49 A6 --- stat Statistics adopted for analysis
51- 55 F5.2 --- beta [-3.98/-1] Mean high-energy photon index
57- 60 F4.2 --- e_beta [0.01/6.71] Lower 1σ uncertainty in beta
62- 65 F4.2 --- E_beta [0.02/2.44] Upper 1σ uncertainty in beta
67- 71 F5.2 --- chi2 [0.3/14.23] Reduced χ2 of the model
73- 80 E8.2 mW/m2 Flux [3.9e-07/0.011] The 0.4-50MeV flux; erg/s/cm2
82- 89 E8.2 mW/m2 e_Flux [3.9e-08/0.001] Uncertainty in Flux
91- 98 E8.2 mJ/m2 Flue [2.76e-08/0.007] The 0.4-50MeV fluence; erg/cm2
100-107 E8.2 mJ/m2 e_Flue [2.8e-09/0.0007] Uncertainty in Flue
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Note (1): Localization facilities as follows:
GBM = Fermi GBM (127 occurrences)
XRT = Swift XRT (57 occurrences)
IPN = Inter-Planetary Network (29 occurrences)
LAT = Fermi LAT (25 occurrences)
BAT = Swift BAT (16 occurrences)
SA = SuperAGILE (2 occurrences)
INT = INTEGRAL (1 occurrence)
ISG = INTEGRAL ISGRI (1 occurrence)
See Section 4.2.
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 A3 --- C Always "GRB"
4- 10 A7 --- GRB GRB identifier (YYMMDDA)
12- 16 A5 --- stat Statistics adopted for analysis
18- 22 F5.2 --- alpha [-1.27/1.35] Mean low-energy photon index
24- 27 F4.2 --- e_alpha [0.02/1.5] Lower 1σ uncertainty in alpha
29- 32 F4.2 --- E_alpha [0.02/0.9] Upper 1σ uncertainty in alpha
34- 38 F5.2 --- beta [-3.3/-2] Mean high-energy photon index
40- 43 F4.2 --- e_beta [0.0/1.55] Lower 1σ uncertainty in beta
45- 48 F4.2 --- E_beta [0.0/2.44] Upper 1σ uncertainty in beta
50- 53 I4 keV Ep [428/1963] Mean peak energy
55- 58 I4 keV e_Ep [369/1193] Lower 1σ uncertainty in Ep
60- 62 I3 keV E_Ep [177/701] Upper 1σ uncertainty in Ep
64- 67 F4.2 --- chi2 [0.7/2.62] Reduced χ2 of the model
69- 76 E8.2 mW/m2 Flux [4e-07/0.008] The 0.4-50MeV flux; erg/s/cm2
78- 85 E8.2 mW/m2 e_Flux [4.1e-08/0.0008] Uncertainty in Flux
87- 94 E8.2 mJ/m2 Flue [5.4e-07/0.006] The 0.4-50MeV fluence; erg/cm2
96-103 E8.2 mJ/m2 e_Flue [5.5e-08/0.0006] Uncertainty in Flue
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 06-Sep-2023