GRB220831A

This page lists all entries on GRB220831A in GRBweb

Summary Fermi GBM IPN Swift GCN 32506 GCN 32508 GCN 32510 GCN 32511 GCN 32513 GCN 32516 GCN 32521 GCN 32529 GCN 32535 GCN 32542 GCN 32548

Summary table
Variable Value Source
GRB_name_Fermi GRB220831581
T0 13:56:32.477 UTC Fermi_GBM
ra 24.2550° Swift
decl -41.5818° Swift
pos_error 1.55e-02° Swift
T90 1.728 s Fermi_GBM
T90_error 1.421 s Fermi_GBM
T90_start 13:56:32.477 UTC Fermi_GBM
fluence 5.05e-07 erg/cm² Fermi_GBM
fluence_error 2.34e-08 erg/cm² Fermi_GBM
T100 1.728 s
GBM_located False
mjd 59822.58093144676 Fermi_GBM
Fermi GBM table
GRB_name_Fermi GRB220831581
trigger_name bn220831581
ra 28.1000°
decl -45.0900°
pos_error 7.69e+00°
datum 2022-08-31
t_trigger 13:56:32.925 UTC
T90 1.728 s
T90_error 1.421 s
T90_start 13:56:32.477 UTC
fluence 5.05e-07 erg/cm²
fluence_error 2.34e-08 erg/cm²
flux_1024 5.86e+00 erg/cm²/s
flux_1024_error 3.14e-01 erg/cm²/s
flux_1024_time -3.84e-01 erg/cm²/s
flux_64 9.45e+00 erg/cm²/s
flux_64_error 1.73e+00 erg/cm²/s
IPN table
GRB_name GRB220831A
ra 24.2542°
decl -41.7500°
pos_error 3.33e-02°
Swift table
GRB_name GRB220831A
t_trigger 13:56:33 UTC
ra 24.2550°
decl -41.5818°
pos_error 1.55e-02°
GCN 32506 table
GRB_name GRB220831A
GCN_number 32506
Detection_method Swift Other
ra 24.2550°
decl -41.5818°
Circular_text TITLE: GCN CIRCULAR NUMBER: 32506 SUBJECT: GRB 220831A: Swift/BAT-GUANO localization of a short burst DATE: 22/09/01 01:55:51 GMT FROM: Aaron Tohuvavohu at U Toronto Aaron Tohuvavohu (U Toronto), Jamie A. Kennea (PSU), James DeLaunay (UAlabama), Gayathri Raman (PSU), report: Swift/BAT did not successfully trigger on GRB 220831A (T0: 2022-08-31 13:56:33 UTC). 10 seconds of serendipitous event data is available covering the time of this burst, associated with BAT failed trigger #1122435. This data was produced due to an unrelated event that occurred close in time to this burst. There is no long duration GUANO data available for this burst due to lack of prompt notice from other instruments. The duration of the burst, as seen by BAT, is ~1 second. In ground analysis of the available event data, we find the position of the burst with SNR 15.0 in the image domain. The BAT position is RA, Dec = 24.2550 -41.5818, which is: RA (J2000) 01h 37m 01.2s Dec (J2000) -41d 34' 54.5" with an estimated uncertainty of 2 arcminutes. XRT and UVOT follow-up has been requested. Results of follow-up observations will be reported in future circulars.
GCN 32508 table
GRB_name GRB220831A
GCN_number 32508
Detection_method Swift Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 32508 SUBJECT: GRB 220831A: Swift ToO observations DATE: 22/09/01 04:19:38 GMT FROM: Phil Evans at U of Leicester P. A. Evans (U. Leicester) reports on behalf of the Swift team: Swift has initiated a ToO observation of the Swift/BAT GRB 220831A. Automated analysis of the XRT data will be presented online at https://www.swift.ac.uk/ToO_GRBs/00021512 Any uncatalogued X-ray sources detected in this analysis will be reported on this website and via GCN COUNTERPART notices. These are not necessarily related to the Swift/BAT event. Any X-ray source considered to be a probable afterglow candidate will be reported via a GCN Circular after manual consideration. Details of the XRT automated analysis methods are detailed in Evans et al. (2007, A&A, 469, 379; 2009, MNRAS, 397, 1177 and 2014, ApJS, 210, 8). This circular is an official product of the Swift-XRT team.
GCN 32510 table
GRB_name GRB220831A
GCN_number 32510
Detection_method Swift-XRT Other
ra 24.2536°
decl -41.5932°
Circular_text TITLE: GCN CIRCULAR NUMBER: 32510 SUBJECT: GRB 220831A: Swift-XRT observations DATE: 22/09/01 16:49:42 GMT FROM: Phil Evans at U of Leicester S. Dichiara (PSU), A.P. Beardmore (U. Leicester), E. Ambrosi (INAF-IASFPA) , M. Capalbi (INAF-IASFPA), M. Perri (SSDC & INAF-OAR), J. D. Gropp (PSU), J.A. Kennea (PSU), A. Tohuvavohu (U. Toronto), J.P. Osborne (U. Leicester) and P.A. Evans (U. Leicester) report on behalf of the Swift-XRT team: Swift-XRT has performed follow-up observations of the Swift/BAT-detected burst GRB 220831A (Tohuvavohu et al. GCN Circ. 32506), collecting 5.0 ks of Photon Counting (PC) mode data between T0+51.2 ks and T0+78.8 ks. No X-ray sources have been detected consistent with being within 98 arcsec of the Swift/BAT position. The 3-sigma upper limit in the field ranges from ~0.002 to ~0.003 ct s^-1, corresponding to a 0.3-10 keV observed flux of 8.1e-14 to 1.1e-13 erg cm^-2 s^-1 (assuming a typical GRB spectrum). We report, however, the presence of a low-significance source, at the following position: RA (J2000): 24.25359 = 01:37:00.86 Dec (J2000): -41.59325 = -41:35:35.70 Error: 6.8 arcsec (radius, 90% conf.) Distance: 41 arcsec from Swift-BAT position. Given the low-significance detection, we cannot state at the present stage if this detection is real or spurious. Six uncatalogued sources were detected too far from the GRB position to be likely afterglow candidates. The results of the XRT-team automatic analysis of the XRT observations, including a position-specific upper limit calculator, are available at https://www.swift.ac.uk/ToO_GRBs/00021512. This circular is an official product of the Swift-XRT team.
GCN 32511 table
GRB_name GRB220831A
GCN_number 32511
Detection_method Fermi GBM Det
t_trigger 13:56:32.930 UTC
ra 28.1000°
decl -45.1000°
Circular_text TITLE: GCN CIRCULAR NUMBER: 32511 SUBJECT: GRB 220831A: Fermi GBM observation DATE: 22/09/01 17:55:47 GMT FROM: Joshua Wood at MSFC/Fermi-GBM J. Wood (NASA/MSFC) and C. Meegan (UAH) report on behalf of the Fermi GBM Team: "At 13:56:32.93 UT on 31 Aug 2022, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 220831A (trigger 683646997 / 220831581). which was also detected by the Swift/BAT-GUANO (A. Tohuvavohu et al. 2022, GCN 32506) The GBM on-ground location is consistent with the Swift position. The on-ground calculated location, using the GBM trigger data, is RA = 28.1, DEC = -45.1 (J2000 degrees, equivalent to 01h 52m, -45d 06'), with an uncertainty of 7.9 degrees (radius, 1-sigma containment, statistical only; there is additionally a systematic error which we have characterized as a core-plus-tail model, with 90% of GRBs having a 3.7 deg error and a small tail suffering a larger than 10 deg systematic error. [Connaughton et al. 2015, ApJS, 216, 32]). The angle from the Fermi LAT boresight is 102.0 degrees. The GBM light curve consists of a single pulse with a duration (T90) of about 1.7 s (50-300 keV). The time-averaged spectrum from T0-0.5 s to T0+1.3 s is best fit by a Band function with Epeak = 46 +/- 8 keV, alpha = -0.67 +/- 0.45, and beta = -2.7 +/- 0.4 The event fluence (10-1000 keV) in this time interval is (5.0 +/- 0.5)E-07 erg/cm^2. The 64-ms peak photon flux measured starting from T0-0.2 s in the 10-1000 keV band is 9.4 +/- 1.7 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog: https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html For Fermi GBM data and info, please visit the official Fermi GBM Support Page: https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/"
GCN 32513 table
GRB_name GRB220831A
GCN_number 32513
Detection_method Swift-BAT Det
ra 24.2540°
decl -41.5929°
Circular_text TITLE: GCN CIRCULAR NUMBER: 32513 SUBJECT: GRB 220831A, VLT/HAWK-I near-infrared observations DATE: 22/09/01 20:48:48 GMT FROM: Daniele B Malesani at Radboud U P. D'Avanzo (INAF/OABr), A. Rossi (INAF/OAS), D. B. Malesani (Radboud and DAWN/NBI), S. Campana (INAF/OABr), A. J. Levan (Radboud univ.) report on behalf of the Stargate collaboration: Following the report of the Swift/BAT/GUANO GRB 220831A (Tohuvavohu et al., GCN 32506; see also Wood & Meegan, GCN 32511) we observed the BAT error circle with the ESO Very Large Telescope, equipped with the HAWK-I near-infrared camera. Observations consisted in 20 min exposure in the J band, with a mean time of 19.4 hr after the GRB. Lacking a deep reference image to check for variability, no claim of a new object can be made based solely on our data. Within the BAT error circle, several objects are apparent in the HAWK-I image which are not visible in the the Legacy survey (z and r bands), which are likely due to color effects. A source is visible in the HAWK-I image which is consistent with the weak X-ray source reported by Dichiara et al. (GCN 32510), at coordinates (J2000): RA = 01:37:00.95 Dec = -41:35:34.37 Its Vega magnitude is J = 21.9 +- 0.09, calibrated against one 2MASS star, and is not detected in the Legacy survey down to limiting magnitudes z > 23.1, r > 24 (all AB). We also note the presence of the nearby galaxy NGC 625, with a NED distance ~4 Mpc, which is 23.6 arcmin (~30 kpc in projection) away from the BAT coordinates of GRB 220831A. We acknowledge the support of the observing staff at Paranal. Further observations are planned.
GCN 32516 table
GRB_name GRB220831A
GCN_number 32516
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 32516 SUBJECT: GRB 220831A: DECam detection of a possible optical counterpart DATE: 22/09/02 15:47:51 GMT FROM: Anais Moller at Australian National U GRB 220831A: DECam detection of a possible optical counterpart J. Freeburn, N. Van Bemmel, D. Dobie, A. Moller, J. Cooke (Swinburne/OzGrav), M. Suhr (Swinburne/ASTRO 3D) report on behalf of the Deeper Wider Faster Collaboration We have observed the Swift/BAT-GUANO localisation of GRB 220831A (GCN 32506) with the Dark Energy Camera (DECam) on the V. M. Blanco 4-m telescope. Imaging in g, r, i were carried out on UT dates 2022-08-31 and 2022-09-01 as part of an ongoing Deeper, Wider, Faster (DWF) program observing run. We detect a source that is spatially coincident with the X-ray (GCN 32510) and near-infrared (GCN 32513) candidate counterpart and is not detected in archival imaging of the field. RA = 01:37:0.965 DEC = -41:35:34.60 We measure: 59823.3 i = 23.13 +/-0.15 59824.3 i = 24.12 +/-0.28 59823.3 r = 23.06 +/-0.12 59824.3 r = 24.32 +/-0.20 59823.1 g < 23.9 59824.3 g < 24.6 Deep spectroscopy is encouraged. We will continue to monitor this source with DECam as part of DWF.
GCN 32521 table
GRB_name GRB220831A
GCN_number 32521
Detection_method Swift-UVOT Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 32521 SUBJECT: GRB 220831A: Swift-UVOT Upper Limits DATE: 22/09/05 22:06:27 GMT FROM: Noel Klingler at NASA-GSFC / UMBC N. J. Klingler (NASA-GSFC/UMBC/CRESST II) reports on behalf of the Swift-UVOT team: Swift-UVOT has performed follow-up observations of the Swift-BAT-detected burst GRB 220831A (Tohuvavohu et al. GCN 32506), collecting 4.7 ks of observations with the White filter between T0+51.2 ks and T0+78.8 ks. No source was detected in the UVOT data at the position of the X-ray source reported by Dichiara et al. (GCN 32510), which is also positionally coincident with the candidate near-infrared and optical counterparts reported by D'Avanzo et al. (GCN 32513) and Freeburn et al. (GCN 32516), respectively. 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) are: Filter T_start(s) T_stop(s) Exp(s) Mag white 51227 78844 4712 >23.39 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.0161684 in the direction of the burst (Schlegel et al. 1998).
GCN 32529 table
GRB_name GRB220831A
GCN_number 32529
Detection_method Swift-XRT Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 32529 SUBJECT: GRB 220831A: ATCA 5/9 GHz radio observations DATE: 22/09/08 02:40:23 GMT FROM: Gemma Anderson at Curtin U G. E. Anderson (Curtin), M. E. Bell (UNewcastle), P. J. Hancock (Curtin), J. C. A. Miller-Jones (Curtin), M. D. Aksulu (UvA), A. Bahramian (Curtin), A. J. van der Horst (GWU), S. D. Ryder (Macquarie), A. Rowlinson (UvA, ASTRON), R. A. M. J. Wijers (UvA) We used the Australia Telescope Compact Array (ATCA) to perform a radio observation of the short GRB 220831A at 5.5 and 9 GHz. The scheduled observations began on 2022 Sept 14 UT for 5 hours (4 days post-burst; Fermi GBM Team GCN 32511, which had been localised by Swift/BAT-GUANO; A. Tohuvavohu et al., GCN 32506). No radio source was detected at the candidate Swift-XRT, VLT/HAWK-I and DECam afterglow position (S. Dichiara et al., GCN 32510; P. D’Avanzo et al., GCN 32513; A. Moller et al., GCN 32516), with 3 sigma upper-limits of 39 microJy and 36 microJy at 5.5 and 9 GHz, respectively. We thank the ATCA and CSIRO Astronomy and Space Science (CASS) staff for scheduling these observations. Gemma Anderson Senior Research Fellow | Curtin Institute of Radio Astronomy (CIRA) International Centre for Radio Astronomy Research (ICRAR) My work days are Monday, Wednesday, Thursday and Friday Curtin University Tel | +61 8 9266 3785 Email | gemma.anderson@curtin.edu.au Pronouns | She/Her [signature_930817360] CRICOS Provider Code 00301J
GCN 32535 table
GRB_name GRB220831A
GCN_number 32535
Detection_method Optical
ra 24.2541°
decl -41.5929°
Circular_text TITLE: GCN CIRCULAR NUMBER: 32535 SUBJECT: GRB 220831A: Gemini-South/GMOS detection of potential optical counterpart DATE: 22/09/08 16:56:10 GMT FROM: Charles Kilpatrick at Northwestern U A. C. Gordon (Northwestern U.), N. Tejos (PUCV), and C. D. Kilpatrick (Northwestern U.) report on behalf of the F4 Collaboration: "We observed the Swift/BAT-GUANO localization of GRB 220831A (Tohuvavohu et al., GCN #32506) with Gemini South/GMOS in follow-up to the DECam observation (Freeburn et al., GCN #32516). Imaging in r- and i-band were carried out starting at UT 2022-09-05 04:05:49. We detect the source in i-band and an upper limit in r-band at the following position (coincident with GCN #32516) at the coordinates (J2000): RA = 01:37:00.9864 Dec = -41:35:34.296 From this source, we measure magnitudes (AB mag): r > 26.4 i = 25.69 +/- 0.31 Our observations confirm that the source presented in GCN #32516 has faded significantly, which supports the hypothesis that it was a transient source associated with GRB 220831A and its weak X-ray counterpart (Dichiara et al., GCN #32510)."
GCN 32542 table
GRB_name GRB220831A
GCN_number 32542
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 32542 SUBJECT: GRB 220831A: Gemini-South Infrared Observations DATE: 22/09/10 20:56:20 GMT FROM: Brendan O'Connor at UMD B. O'Connor (UMD/GWU), E. Troja (UTV/ASU), S. Dichiara (PSU), on behalf of a larger collaboration: We performed target of opportunity observations of GRB 220831A (Tohuvavohu et al. GCN 32506) with the FLAMINGOS-2 spectrograph mounted on the Gemini-South telescope. Observations were taken in the J and Ks filters with total exposure of 1785 and 1635 s, respectively. The observations began at 2022-09-09 03:27:01 UT, corresponding to ~8.6 d after the burst. Further observations were obtained the following night (~9.6 d) in J-band for 2000 s exposure. At the location of the optical, infrared, and X-ray counterpart (Dichiara et al. GCN 32510, D'Avanzo et al. GCN 32513, Freeburn et al. GCN 32516, Gordon et al. GCN 32535), we detect a faint source with brightness J ~ 24.5 AB mag. This result confirms the fading of the infrared source reported by D'Avanzo et al. GCN 32513. Our measurement implies a very red color, r-J >2, of the late time emission. At present it is not clear whether this is due to the onset of a kilonova or to the contribution of an underlying host galaxy. Assuming a behavior similar to AT2017gfo, the apparent J-band magnitude implies a distance of ~200 Mpc. However, the nearby galaxy noted by D’Avanzo et al. GCN 32513 is significantly closer at only 4 Mpc. If instead the source is dominated by the host galaxy contribution, the red color suggests that GRB 220831A was a distant event (see, e.g., O'Connor et al. 2022, MNRAS, 515, 4890). Further observations are planned. Magnitudes are calibrated against stars in the 2MASS catalog and are not corrected for Galactic extinction. We thank the staff of the Gemini Observatory, in particular Joan Font-Serra and Yijung Kang, for rapid scheduling of these observations.
GCN 32548 table
GRB_name GRB220831A
GCN_number 32548
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 32548 SUBJECT: GRB 220831A: DECam optical counterpart follow-up DATE: 22/09/12 07:33:12 GMT FROM: Anais Moller at Australian National U GRB 220831A: DECam optical counterpart follow-up J. Freeburn, N. Van Bemmel, D. Dobie, A. Moller, J. Cooke (Swinburne/OzGrav), M. Suhr (Swinburne/ASTRO 3D), S. Webb (Swinburne) report on behalf of the Deeper, Wider, Faster Collaboration We have carried out additional observations further to GCN 32516 of the optical counterpart (RA = 01:37:0.965, DEC = -41:35:34.60) to GRB220831A (GCN 32506). Here we present source observations using the Dark Energy Camera (DECam) on the V. M. Blanco 4-m telescope and revised, forced photometry of our previous observations using NOAO calibrated images. Images were taken in g, r, i on UT dates 2022-08-31 to 2022-09-04 as additional observations during the Deeper, Wider, Faster (DWF) program observing run. Our photometry, along with those of Gordon et al. (GCN 32535) and D'Avanzo et al. (GCN 32513) are consistent with current short GRB optical afterglow models. The following detection and upper limits (not corrected for Galactic extinction): T-start (MJD) filter detection/UL 59823.200 g 23.17 +/- 0.18 59823.203 r 22.885 +/- 0.088 59823.209 i 23.06 +/- 0.13 59823.384 g 23.72 +/- 0.30 59823.395 r 23.37 +/- 0.13 59823.389 i 23.12 +/- 0.13 59824.198 g 24.33 +/- 0.37 59824.203 r 24.69 +/- 0.35 59824.208 i 23.86 +/- 0.22 59824.377 g 24.94 +/- 0.59 59824.390 r 24.13 +/- 0.25 59824.391 i 24.10 +/- 0.25 59825.300 r >24.8 59825.301 i >24.4 59826.306 i >25.0