GRB120922A

This page lists all entries on GRB120922A in GRBweb

Summary Fermi GBM IPN Swift GCN 13793 GCN 13794 GCN 13795 GCN 13799 GCN 13800 GCN 13803 GCN 13804 GCN 13806 GCN 13808 GCN 13809 GCN 13810

Summary table
Variable Value Source
GRB_name_Fermi GRB120922939
T0 22:30:15.808 UTC Fermi_GBM
ra 234.7483° Swift
decl -20.1818° Swift
pos_error 8.41e-05° Swift
T90 182.275 s Fermi_GBM
T90_error 19.777 s Fermi_GBM
T90_start 22:30:15.808 UTC Fermi_GBM
fluence 8.21e-06 erg/cm² Fermi_GBM
fluence_error 1.69e-07 erg/cm² Fermi_GBM
redshift 3.1000
T100 185.192 s
GBM_located False
mjd 56192.93768296296 Fermi_GBM
Fermi GBM table
GRB_name_Fermi GRB120922939
trigger_name bn120922939
ra 234.7479°
decl -20.1822°
pos_error 6.64e+00°
datum 2012-09-22
t_trigger 22:32:09.474 UTC
T90 182.275 s
T90_error 19.777 s
T90_start 22:30:15.808 UTC
fluence 8.21e-06 erg/cm²
fluence_error 1.69e-07 erg/cm²
flux_1024 3.41e+00 erg/cm²/s
flux_1024_error 2.79e-01 erg/cm²/s
flux_1024_time -1.79e+00 erg/cm²/s
flux_64 5.63e+00 erg/cm²/s
flux_64_error 1.43e+00 erg/cm²/s
IPN table
GRB_name GRB120922A
ra 234.7542°
decl -20.1833°
pos_error 5.00e-02°
Swift table
GRB_name GRB120922A
t_trigger 22:30:28 UTC
ra 234.7483°
decl -20.1818°
pos_error 8.41e-05°
T90 173.0 s
fluence 6.20e-06 erg/cm²
redshift 3.1000
GCN 13793 table
GRB_name GRB120922A
GCN_number 13793
Detection_method Swift Det
t_trigger 22:30:28 UTC
ra 234.7560°
decl -20.1770°
Circular_text TITLE: GCN CIRCULAR NUMBER: 13793 SUBJECT: GRB 120922A: Swift detection of a burst DATE: 12/09/22 22:41:52 GMT FROM: David Palmer at LANL V. N. Yershov (UCL-MSSL), S. D. Barthelmy (GSFC), H. A. Krimm (CRESST/GSFC/USRA), N. P. M. Kuin (UCL-MSSL), C. J. Mountford (U Leicester), K. L. Page (U Leicester), D. M. Palmer (LANL), M. H. Siegel (PSU) and T. N. Ukwatta (MSU) report on behalf of the Swift Team: At 22:30:28 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 120922A (trigger=534394). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 234.756, -20.177 which is RA(J2000) = 15h 39m 01s Dec(J2000) = -20d 10' 36" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a multiple-peaked structure with a duration of at least 130 sec. The peak count rate was ~3000 counts/sec (15-350 keV), at ~102 sec after the trigger. The XRT began observing the field at 22:32:25.0 UT, 116.5 seconds after the BAT trigger. XRT found a bright, uncatalogued X-ray source located at RA, Dec 234.7505, -20.1839 which is equivalent to: RA(J2000) = +15h 39m 0.12s Dec(J2000) = -20d 11' 02.0" with an uncertainty of 5.6 arcseconds (radius, 90% containment). This location is 31 arcseconds from the BAT onboard position, within the BAT error circle. No event data are yet available to determine the column density using X-ray spectroscopy. The initial flux in the 0.1 s image was 2.53e-08 erg cm^-2 s^-1 (0.2-10 keV). UVOT took a finding chart exposure of 150 seconds with the White filter starting 126 seconds after the BAT trigger. No credible afterglow candidate has been found in the initial data products. The 2.7'x2.7' sub-image covers 100% of the XRT error circle. The typical 3-sigma upper limit has been about 19.6 mag. The 8'x8' region for the list of sources generated on-board covers 100% of the XRT error circle. The list of sources is typically complete to about 18 mag. No correction has been made for the expected extinction corresponding to E(B-V) of 0.15. Burst Advocate for this burst is V. N. Yershov (vny AT mssl.ucl.ac.uk). Please contact the BA by email if you require additional information regarding Swift followup of this burst. In extremely urgent cases, after trying the Burst Advocate, you can contact the Swift PI by phone (see Swift TOO web site for information: http://www.swift.psu.edu/too.html.)
GCN 13794 table
GRB_name GRB120922A
GCN_number 13794
Detection_method Swift-XRT Other
ra 234.7483°
decl -20.1821°
Circular_text TITLE: GCN CIRCULAR NUMBER: 13794 SUBJECT: GRB 120922A: Prompt enhanced Swift-XRT position DATE: 12/09/22 23:28:41 GMT FROM: Phil Evans at U of Leicester P.A. Evans (U. Leicester) reports on behalf of the Swift-XRT team: Using promptly downlinked XRT event data for GRB 120922A, we find an enhanced XRT position of the afterglow: RA, Dec: 234.7483, -20.1821 which is equivalent to: RA (J2000) = 15 38 59.60 Dec (J2000) = -20 10 55.4 with an uncertainty of 2.0 arcseconds (radius, 90% confidence). Analysis of the promptly available data is online at http://www.swift.ac.uk/sper/534394. Position enhancement is is described by Goad et al. (2007, A&A, 476, 1401) and Evans et al. (2009, MNRAS, 397, 1177). This circular is an official product of the Swift-XRT team.
GCN 13795 table
GRB_name GRB120922A
GCN_number 13795
Detection_method GROND
ra 234.7485°
decl -20.1817°
Circular_text TITLE: GCN CIRCULAR NUMBER: 13795 SUBJECT: GRB 120922A: GROND afterglow candidate DATE: 12/09/23 00:29:21 GMT FROM: Sylvio Klose at TLS Tautenburg F. Knust (MPE Garching), T. Kruehler (DARK), J. Greiner (MPE) and S. Klose (TLS Tautenburg) report on behalf of the GROND team: We observed the field of GRB 120922A (Swift trigger 534394; Yershov et al., GCN 13793) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, PASP 120, 405) mounted at the 2.2m MPG/ESO telescope at La Silla Observatory (Chile). Observations started at 23:30 UT on Sep 22, 60 min after the GRB trigger. We detect a bright source within the enhanced Swift/XRT error circle reported by Evans (GCN 13794) at coordinates RA, DEC (J2000) = 15:38:59.64, -20:10:54.2 (+/- 0.3 arcsec) with (AB mag) r' = 19.5 +/- 0.1, calibrated against the GROND zeropoint and not corrected for the Galactic foreground reddening of E_(B-V)= 0.15 mag in the direction of the burst (Schlegel et al. 1998).
GCN 13799 table
GRB_name GRB120922A
GCN_number 13799
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 13799 SUBJECT: GRB 120922A: TAROT La Silla observatory optical observations DATE: 12/09/23 06:35:19 GMT FROM: Alain Klotz at CESR-CNRS Klotz A. (IRAP-CNRS-OMP), Gendre B. (ASDC/INAF-OAR), Boer M. (UNS-CNRS-OCA), Atteia J.L. (IRAP-CNRS-OMP) report: We imaged the field of GRB 120922A detected by SWIFT (trigger 534394) with the TAROT robotic telescope (D=25cm) located at the European Southern Observatory, La Silla observatory, Chile. The observations started 56 min after the GRB trigger (starting at twilight). The elevation of the field decreased from 46 degrees above horizon and weather conditions were good. Co addition of TAROT images from 56 to 85 minutes after the GRB, shows the optical candidate reported by Knust et al. (GCNC 13795) at magnitude R~20 (close to the limiting magnitude of TAROT). Note the source NOMAD1 0698-0330778 (R.A.=234.7496389 Decl=-20.1828917 J2000) R=19.79 few arcsec southeastern from the OT. This message may be cited.
GCN 13800 table
GRB_name GRB120922A
GCN_number 13800
Detection_method Swift-XRT Det
ra 234.7486°
decl -20.1820°
Circular_text TITLE: GCN CIRCULAR NUMBER: 13800 SUBJECT: GRB 120922A: Enhanced Swift-XRT position DATE: 12/09/23 07:37:00 GMT FROM: Phil Evans at U of Leicester P.A. Evans, M.R. Goad, J.P. Osborne and A.P. Beardmore (U. Leicester) report on behalf of the Swift-XRT team. Using 1474 s of XRT Photon Counting mode data and 1 UVOT images for GRB 120922A, we find an astrometrically corrected X-ray position (using the XRT-UVOT alignment and matching UVOT field sources to the USNO-B1 catalogue): RA, Dec = 234.74858, -20.18203 which is equivalent to: RA (J2000): 15h 38m 59.66s Dec (J2000): -20d 10' 55.3" with an uncertainty of 1.7 arcsec (radius, 90% confidence). This position may be improved as more data are received. The latest position can be viewed at http://www.swift.ac.uk/xrt_positions. Position enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans et al. (2009, MNRAS, 397, 1177). This circular was automatically generated, and is an official product of the Swift-XRT team.
GCN 13803 table
GRB_name GRB120922A
GCN_number 13803
Detection_method Swift-UVOT Det
ra 234.7483°
decl -20.1818°
Circular_text TITLE: GCN CIRCULAR NUMBER: 13803 SUBJECT: GRB 120922A: Swift/UVOT Observations DATE: 12/09/23 10:33:30 GMT FROM: Vladimir Yershov at MSSL V.N. Yershov (UCL-MSSL), aN. P. M. Kuin (MSSL-UCL) and A. A. Breeveld (MSSL-UCL), report on behalf of the Swift-UVOT team: UVOT took a finding chart exposure of 150 seconds with the White filter starting 864 seconds after the BAT trigger. There is a candidate afterglow in the rapidly available 2.7'x2.7' sub-image at RA(J2000) = 15:38:59.60 = 234.74832 DEC(J2000) = -20:10:54.3 = -20.18175 with a 90%-confidence error radius of about 0.65 arc sec. This position is 2.0 arc sec. from the center of the XRT error circle. The estimated magnitude is 18.91 with a 1-sigma error of about 0.16. No correction has been made for the expected extinction corresponding to E(B-V) of 0.15.
GCN 13804 table
GRB_name GRB120922A
GCN_number 13804
Detection_method Swift-XRT Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 13804 SUBJECT: GRB 120922A: Swift-XRT refined Analysis DATE: 12/09/23 10:42:03 GMT FROM: Phil Evans at U of Leicester A. Melandri (INAF-OAB), D.N. Burrows (PSU), J.A. Kennea (PSU), M.C. Stroh (PSU), C. Pagani (U. Leicester), A.P. Beardmore (U. Leicester), P.A. Evans (U. Leicester), B. Sbarufatti (INAF-OAB/PSU), G. Stratta (ASDC) and V.N. Yershov report on behalf of the Swift-XRT team: We have analysed 9.3 ks of XRT data for GRB 120922A (Yershov et al. GCN Circ. 13793), from 120 s to 19.4 ks after the BAT trigger. The data comprise 484 s in Windowed Timing (WT) mode with the remainder in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Evans et al. (GCN. Circ 13794). The light curve can be modelled with a series of power-law decays. The light curve initially rises, with an index alpha=-1.5 (+0.0, -1.3). At T+130 s it breaks to an alpha of 3.09 (+0.09, -0.08). The light curve breaks again at T+243 s to a decay with alpha=3.83 (+0.09, -0.10), before a final break at T+737 s s after which the decay index is 0.85 (+0.04, -0.05). A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 2.33 (+/-0.04). The best-fitting absorption column is 2.15 (+/-0.09) x 10^21 cm^-2, in excess of the Galactic value of 7.7 x 10^20 cm^-2 (Kalberla et al. 2005). The PC mode spectrum has a photon index of 2.11 (+0.13, -0.12) and a best-fitting absorption column of 1.06 (+0.28, -0.27) x 10^21 cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.5 x 10^-11 (4.6 x 10^-11) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Total column: 1.06 (+0.28, -0.27) x 10^21 cm^-2 Galactic foreground: 7.7 x 10^20 cm^-2 Excess significance: 1.8 sigma Photon index: 2.11 (+0.13, -0.12) The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00534394. This circular is an official product of the Swift-XRT team.
GCN 13806 table
GRB_name GRB120922A
GCN_number 13806
Detection_method Swift-BAT Det
ra 234.7580°
decl -20.1810°
Circular_text TITLE: GCN CIRCULAR NUMBER: 13806 SUBJECT: GRB 120922A: Swift-BAT refined analysis DATE: 12/09/23 13:36:02 GMT FROM: Scott Barthelmy at NASA/GSFC H. A. Krimm (GSFC/USRA), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (GSFC/UMBC), G. Sato (ISAS), M. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (MSU), V. N. Yershov (UCL-MSSL) (i.e. the Swift-BAT team): Using the data set from T-239 to T+303 sec from recent telemetry downlinks, we report further analysis of BAT GRB 120922A (trigger #534394) (Yershov, et al., GCN Circ. 13793). The BAT ground-calculated position is RA, Dec = 234.758, -20.181 deg, which is RA(J2000) = 15h 39m 02.0s Dec(J2000) = -20d 10' 51.8" with an uncertainty of 1.2 arcmin, (radius, sys+stat, 90% containment). The partial coding was 33%. The mask-weighted light curve shows low-level emission starting at T-200 sec, possibly sooner before the data capture started, with peaks at ~T_0, ~T+60, & ~T+105 sec, and ending at ~T+205 sec. T90 (15-350 keV) is 173 +- 33 sec (estimated error including systematics). The time-averaged spectrum from T-22.58 to T+215.73 sec is best fit by a power law with an exponential cutoff. This fit gives a photon index 1.58 +- 0.36, and Epeak of 38.2 +- 0.0 keV (chi squared 54.3 for 56 d.o.f.). For this model the total fluence in the 15-150 keV band is 6.2 +- 0.7 x 10^-6 erg/cm2 and the 1-sec peak flux measured from T+99.21 sec in the 15-150 keV band is 2.0 +- 0.2 ph/cm2/sec. A fit to a simple power law gives a photon index of 2.09 +- 0.08 (chi squared 61.1 for 57 d.o.f.). All the quoted errors are at the 90% confidence level. The results of the batgrbproduct analysis are available at http://gcn.gsfc.nasa.gov/notices_s/534394/BA/
GCN 13808 table
GRB_name GRB120922A
GCN_number 13808
Detection_method Swift-UVOT Det
Circular_text TITLE: GCN CIRCULAR NUMBER: 13808 SUBJECT: GRB 120922A: Swift/UVOT Detection DATE: 12/09/23 17:08:12 GMT FROM: Paul Kuin at MSSL N. P. M. Kuin (MSSL/UCL) and V.N. Yershov (MSSL/UCL) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 120922A 127 s after the BAT trigger (Yershov et al., GCN Circ. 13793). A source consistent with the XRT position (Evans et al. GCN Circ. 13800), and the initial optical detection by GROND (Knust et al., GCN Circ. 13795) is detected in the initial UVOT exposures (Yershov et al. GCN Circ. 13803). The uvot observations show a slow initial rise in brightness peaking around 900s after the trigger. The burst is only detected in the v,b and white filters which is probably due to the high galactic reddening. Preliminary detections and 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early exposures are: Filter T_start(s) T_stop(s) Exp(s) Mag white 126 276 147 >20.67 white 865 1014 147 19.34 +/- 0.14 v 615 1239 78 17.94 +/- 0.22 b 541 733 78 >19.17 b 1145 2030 119 19.62 +/- 0.36 u 285 534 250 >19.98 u 688 1139 40 >18.82 w1 664 16852 1434 >20.95 m2 639 11081 1232 >20.96 w2 590 12900 1424 >21.20 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.15 in the direction of the burst (Schlegel et al. 1998).
GCN 13809 table
GRB_name GRB120922A
GCN_number 13809
Detection_method Fermi GBM Det
t_trigger 22:32:09.470 UTC
Circular_text TITLE: GCN CIRCULAR NUMBER: 13809 SUBJECT: GRB 120922A: Fermi GBM detection DATE: 12/09/23 18:23:16 GMT FROM: George A. Younes at USRA/NASA/MSFC George Younes (MSFC/USRA) reports on behalf of the Fermi GBM Team: "At 22:32:09.47 UT on 22 September 2012, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 120922A (trigger 370045932 / 120922939) which was also detected by the Swift/BAT (Yershov et al. 2012, GCN 13793). The GBM on-ground location is consistent with the Swift position. The angle from the Fermi LAT boresight is 85 degrees. The GBM light curve consists of a multiple peaks with a duration (T90) of about 180 s (50-300 keV). The time-averaged spectrum from T0-121 s to T0+6 s is best fit by a Band function with Epeak = 37.7 +/- 3.5 keV, alpha = 1.6 +/- 0.7 , and beta = -2.3 +/- 0.1. The event fluence (10-1000 keV) in this time interval is (6.5 +/- 0.4)E-06 ergs/cm^2. The 1-sec peak photon flux measured starting from T0-1.8 s in the 10-1000 keV band is 3.4 +/- 0.3 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."
GCN 13810 table
GRB_name GRB120922A
GCN_number 13810
Detection_method GROND
redshift 3.1000
Circular_text TITLE: GCN CIRCULAR NUMBER: 13810 SUBJECT: GRB 120922A: GROND photometric redshift DATE: 12/09/23 21:23:29 GMT FROM: Fabian Knust at MPE/GROND F. Knust (MPE Garching), T. Kruehler (DARK/NBI), S. Klose (TLS Tautenburg) and J. Greiner (MPE Garching) report on behalf of the GROND team: We report on further analysis of the GROND (Greiner et al. 2008, PASP 120, 405) optical/NIR imaging of the afterglow (Knust et al. GCN 13795, Klotz et al., GCN 13799, Yershov et al., GCN 13803, Kuin et al., GCN 13808) of GRB 120922A (Yershov et al., GCN 13793). Tying our photometric solution to field stars from the SDSS in the optical filters and 2MASS in the NIR, we derive the following AB magnitudes centered at a midtime of 00:01 UTC on September 23 (approx 1.5 hrs after the trigger): g' = 20.53 +/- 0.05 r' = 19.69 +/- 0.04 i' = 19.44 +/- 0.04 z' = 19.28 +/- 0.04 J = 18.92 +/- 0.06 H = 18.79 +/- 0.07 K = 18.63 +/- 0.10 After correcting these magnitudes for the expected Galactic foreground extinction corresponding to a reddening of E_B-V = 0.15 mag (Schlegel et al. 1998), the SED is well fit with a simple power law of spectral index \beta = 0.5 +/- 0.2 and no strong evidence for host-intrinsic reddening. The significant drop in flux in the g'-band suggests a photometric redshift of 3.1 +/- 0.2, consistent with the lack of detection in the bluer UVOT filters (Kuin et al., GCN 13808).