GRB220826A

This page lists all entries on GRB220826A in GRBweb

Summary Fermi GBM IPN Swift GCN 32484 GCN 32485 GCN 32486 GCN 32487 GCN 32488 GCN 32489 GCN 32491 GCN 32495 GCN 32496 GCN 32500

Summary table
Variable Value Source
GRB_name_Fermi GRB220826497
T0 11:55:21 UTC GCN_circulars,Swift Det
ra 206.4105° Swift
decl -44.0387° Swift
pos_error 5.82e-05° Swift
T90 16.64 s Fermi_GBM
T90_error 1.056 s Fermi_GBM
T90_start 11:55:21.701 UTC Fermi_GBM
fluence 2.11e-06 erg/cm² Fermi_GBM
fluence_error 2.69e-08 erg/cm² Fermi_GBM
T100 17.341 s
GBM_located False
mjd 59817.496770833335 GCN_circulars,Swift Det
Fermi GBM table
GRB_name_Fermi GRB220826497
trigger_name bn220826497
ra 206.4308°
decl -44.0439°
pos_error 5.43e+00°
datum 2022-08-26
t_trigger 11:55:22.981 UTC
T90 16.64 s
T90_error 1.056 s
T90_start 11:55:21.701 UTC
fluence 2.11e-06 erg/cm²
fluence_error 2.69e-08 erg/cm²
flux_1024 4.30e+00 erg/cm²/s
flux_1024_error 2.94e-01 erg/cm²/s
flux_1024_time 5.18e+00 erg/cm²/s
flux_64 6.82e+00 erg/cm²/s
flux_64_error 1.39e+00 erg/cm²/s
IPN table
GRB_name GRB220826A
ra 206.4333°
decl -44.0500°
pos_error 5.00e-02°
Swift table
GRB_name GRB220826A
t_trigger 11:55:21 UTC
ra 206.4105°
decl -44.0387°
pos_error 5.82e-05°
T90 11.14 s
fluence 1.20e-06 erg/cm²
GCN 32484 table
GRB_name GRB220826A
GCN_number 32484
Detection_method Swift Det
t_trigger 11:55:21 UTC
ra 206.4310°
decl -44.0440°
Circular_text TITLE: GCN CIRCULAR NUMBER: 32484 SUBJECT: GRB 220826A: Swift detection of a burst with an optical counterpart DATE: 22/08/26 12:05:48 GMT FROM: David Palmer at LANL R. Caputo (GSFC), P. A. Evans (U Leicester), J.D. Gropp (PSU), J. A. Kennea (PSU), N. P. M. Kuin (UCL-MSSL), F. E. Marshall (NASA/GSFC), K. L. Page (U Leicester), D. M. Palmer (LANL) and M. H. Siegel (PSU) report on behalf of the Neil Gehrels Swift Observatory Team: At 11:55:21 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 220826A (trigger=1121751). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 206.431, -44.044 which is RA(J2000) = 13h 45m 44s Dec(J2000) = -44d 02' 39" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a complex structure with a duration of about 20 sec. The peak count rate was ~3500 counts/sec (15-350 keV), at ~7 sec after the trigger. The XRT began observing the field at 11:56:42.9 UT, 81.2 seconds after the BAT trigger. Using promptly downlinked data we find a bright, uncatalogued X-ray source located at RA, Dec 206.41169, -44.03885 which is equivalent to: RA(J2000) = 13h 45m 38.81s Dec(J2000) = -44d 02' 19.9" with an uncertainty of 3.5 arcseconds (radius, 90% containment). This location is 53 arcseconds from the BAT onboard position, within the BAT error circle. This position may be improved as more data are received; the latest position is available at https://www.swift.ac.uk/sper. A power-law fit to a spectrum formed from promptly downlinked event data gives a column density in excess of the Galactic value (9.05 x 10^20 cm^-2, Willingale et al. 2013), with an excess column of 2.8 (+2.60/-2.30) x 10^21 cm^-2 (90% confidence). UVOT took a finding chart exposure of 150 seconds with the White filter starting 90 seconds after the BAT trigger. There is a candidate afterglow in the rapidly available 2.7'x2.7' sub-image at RA(J2000) = 13:45:38.52 = 206.41049 DEC(J2000) = -44:02:19.0 = -44.03862 with a 90%-confidence error radius of about 0.62 arc sec. This position is 3.3 arc sec. from the center of the XRT error circle. The estimated magnitude is 17.89 with a 1-sigma error of about 0.15. No correction has been made for the expected extinction corresponding to E(B-V) of 0.110. Burst Advocate for this burst is R. Caputo (regina.caputo AT nasa.gov). 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/)
GCN 32485 table
GRB_name GRB220826A
GCN_number 32485
Detection_method Swift-XRT Det
ra 206.4108°
decl -44.0392°
Circular_text TITLE: GCN CIRCULAR NUMBER: 32485 SUBJECT: GRB 220826A: Enhanced Swift-XRT position DATE: 22/08/26 14:54:34 GMT FROM: Phil Evans at U of Leicester A.P. Beardmore, P.A. Evans, M.R. Goad and J.P. Osborne (U. Leicester) report on behalf of the Swift-XRT team. Using 744 s of XRT Photon Counting mode data and 1 UVOT images for GRB 220826A, 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 = 206.41081, -44.03917 which is equivalent to: RA (J2000): 13h 45m 38.59s Dec (J2000): -44d 02' 21.0" with an uncertainty of 2.2 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 32486 table
GRB_name GRB220826A
GCN_number 32486
Detection_method Swift Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 32486 SUBJECT: Swift GRB 220826A: Global MASTER-Net observations report DATE: 22/08/26 17:24:17 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, G.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin (Lomonosov Moscow State University, SAI, Physics Department), R. Podesta, C.Lopez, F. Podesta, C.Francile (Observatorio Astronomico Felix Aguilar OAFA), R. Rebolo, M. Serra (The Instituto de Astrofisica de Canarias), D. Buckley (South African Astronomical Observatory), O.A. Gres, N.M. Budnev (Irkutsk State University, API), L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez (INAOE, Guillermo Haro Astrophysics Observatory), A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), A. Gabovich, V.Yurkov (Blagoveschensk Educational State University) MASTER-SAAO robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South Africa (South African Astronomical Observatory) was pointed to the Swift GRB 220826A ( R. Caputo et al., GCN 32484) errorbox 19090 sec after notice time and 19104 sec after trigger time at 2022-08-26 17:13:46 UT, with upper limit up to 17.8 mag. Observations started at twilight. The observations began at zenith distance = 39 deg. The sun altitude is -12.5 deg. The galactic latitude b = 17 deg., longitude l = 314 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2068190 We obtain a following upper limits. Tmid-T0 | Site |Filt.| Expt. | Limit| Comment _________|_____________________|_____|_______|______|________ 19194 | MASTER-SAAO | C | 180 | 17.8 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited.
GCN 32487 table
GRB_name GRB220826A
GCN_number 32487
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 32487 SUBJECT: GRB 220826A: iTelescope optical afterglow observations DATE: 22/08/26 17:55:46 GMT FROM: Filipp Dmitrievich Romanov at Amateur astronomer I observed the field of GRB 220826A (Caputo et al., GCN Circ. 32484) using remote telescope T59 (0.51-m f/6.8 reflector + CCD) of iTelescope.Net in Siding Spring Observatory (Australia) on 2022-08-26. Three images were obtained from 12:16:07 UTC (1246 sec. after the trigger) with a Luminance filter (300 seconds exposures, BINx1), but in the third of them, the object is already below the minimum target elevation for the telescope. I clearly detected (SNR ~ 8 in the stacked image) the optical afterglow with UVOT position and measured its magnitude = 19.3 +/- 0.2 in the stacked image (midtime = 12:23:09 UTC means 1668 sec. after the trigger), airmass was from 4.041 to 4.463. I compared with Sloan r' magnitudes of nearby stars from APASS DR9 catalogue (Henden et al., 2016). Magnitude was not corrected for Galactic extinction. Stacked image available here: https://www.flickr.com/photos/filipp-romanov/52313060415
GCN 32488 table
GRB_name GRB220826A
GCN_number 32488
Detection_method Swift-UVOT Det
ra 206.4105°
decl -44.0387°
Circular_text TITLE: GCN CIRCULAR NUMBER: 32488 SUBJECT: GRB 220826A: Swift/UVOT Detection DATE: 22/08/26 18:47:37 GMT FROM: Paul Kuin at MSSL N. P. M. Kuin (UCL-MSSL) and R. Caputo (GSFC) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 220826A 91 s after the BAT trigger (Caputo et al., GCN Circ. 32484). A source consistent with the XRT position (Beardmore et al. GCN Circ. 32485) is detected in the initial UVOT exposures. The preliminary UVOT position is: RA (J2000) = 13:45:38.51 = 206.41047 (deg.) Dec (J2000) = -44:02:19.2 = -44.03866 (deg.) with an estimated uncertainty of 0.45 arc sec. (radius, 90% confidence). 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 91 240 147 18.12 +/- 0.05 v 632 827 39 >18.4 b 559 753 39 >18.6 u 303 553 246 18.69 +/- 0.13 w1 682 702 19 >17.7 m2 831 851 19 >17.8 w2 608 802 39 >19.2 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.110 in the direction of the burst (Schlegel et al. 1998).
GCN 32489 table
GRB_name GRB220826A
GCN_number 32489
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 32489 SUBJECT: GRB 220826A: Lesedi optical afterglow detection DATE: 22/08/26 18:59:01 GMT FROM: Simon de Wet at UCT S. de Wet (UCT) and D.B. Malesani (Radboud and DAWN/NBI) report: Following the detection of GRB 220826A by Swift and its X-ray and optical counterparts (Caputo et al., GCN 32484; Kuin et al., GCN 32488; Romanov F.P., GCN 32487), the 1m Lesedi optical telescope located at Sutherland, South Africa, obtained 600 s exposures in each of the g,r,i and z bands with the Mookodi low-resolution spectrograph and imager beginning at 17:27:09 UT, approximately 0.23 days post-trigger. We detect the optical afterglow to GRB 220826A in each image at the UVOT position with the following AB magnitude, calibrated to Skymapper flux measurements of a nearby star in the field: r = 21.48 +/- 0.16 Lesedi is built and operated by the South African Astronomical Observatory.
GCN 32491 table
GRB_name GRB220826A
GCN_number 32491
Detection_method Swift-XRT Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 32491 SUBJECT: GRB 220826A: Swift-XRT refined Analysis DATE: 22/08/27 00:49:19 GMT FROM: Phil Evans at U of Leicester A. Tohuvavohu (U. Toronto), J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), A.P. Beardmore (U. Leicester), P. D'Avanzo (INAF-OAB), M.G. Bernardini (INAF-OAB), E. Ambrosi (INAF-IASFPA) , D.N. Burrows (PSU), J. D. Gropp (PSU) and R. Caputo report on behalf of the Swift-XRT team: We have analysed 6.5 ks of XRT data for GRB 220826A (Caputo et al. GCN Circ. 32484), from 70 s to 33.8 ks after the BAT trigger. The data comprise 37 s in Windowed Timing (WT) mode (the first 9 s were taken while Swift was slewing) with the remainder in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Beardmore et al. (GCN Circ. 32485). The late-time light curve (from T0+5.0 ks) can be modelled with a power-law decay with a decay index of alpha=1.25 (+/-0.18). A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 1.80 (+0.16, -0.15). The best-fitting absorption column is 1.6 (+/-0.5) x 10^21 cm^-2, in excess of the Galactic value of 9.1 x 10^20 cm^-2 (Willingale et al. 2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.9 x 10^-11 (4.8 x 10^-11) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Total column: 1.6 (+/-0.5) x 10^21 cm^-2 Galactic foreground: 9.1 x 10^20 cm^-2 Excess significance: 2.4 sigma Photon index: 1.80 (+0.16, -0.15) If the light curve continues to decay with a power-law decay index of 1.25, the count rate at T+24 hours will be 5.0 x 10^-3 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 2.0 x 10^-13 (2.4 x 10^-13) erg cm^-2 s^-1. The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/01121751. This circular is an official product of the Swift-XRT team.
GCN 32495 table
GRB_name GRB220826A
GCN_number 32495
Detection_method Fermi GBM Det
t_trigger 11:55:22.980 UTC
Circular_text TITLE: GCN CIRCULAR NUMBER: 32495 SUBJECT: GRB 220826A: Fermi GBM observation DATE: 22/08/27 11:13:39 GMT FROM: Andreas von Kienlin at MPE P. Veres and C. Meegan (both UAH) report on behalf of the Fermi GBM Team: "At 11:55:22.98 UT on 26 August 2022, the Fermi Gamma-Ray Burst Monitor (GBM) triggered and located GRB 220826A (trigger 220826497 / 683207727) which was also detected by the Swift/BAT (Caputo et al., GCN 32484) The GBM on-ground location is consistent with the Swift position. The angle from the Fermi LAT boresight at the GBM trigger time is 54 degrees. The GBM light curve shows two pulses with a duration (T90) of about 16.6 s (50-300 keV). The time-averaged spectrum from T0-0.5 s to T0+10.8 s is best fit by a power law function with an exponential high-energy cutoff. The power law index is -0.66 +/- 0.20 and the cutoff energy, parameterized as Epeak, is 113 +/- 14 keV The event fluence (10-1000 keV) in this time interval is (1.50 +/- 0.14)E-6 erg/cm^2. The 1-sec peak photon flux measured starting from T0 + 5.2 s in the 10-1000 keV band is 4.3 +/- 0.3 ph/s/cm^2. A Band function fits the spectrum equally well with Epeak= 66 +/- 13 keV, alpha = 0.28 +/- 0.58 and beta = -2.14 +/- 0.18. 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 32496 table
GRB_name GRB220826A
GCN_number 32496
Detection_method Swift-BAT Det
ra 206.4210°
decl -44.0360°
Circular_text TITLE: GCN CIRCULAR NUMBER: 32496 SUBJECT: GRB 220826A: Swift-BAT refined analysis DATE: 22/08/27 19:50:26 GMT FROM: Amy Lien at GSFC T. Sakamoto (AGU), S. D. Barthelmy (GSFC), H. A. Krimm (NSF), S. Laha (GSFC/UMBC), A. Y. Lien (U Tampa), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Parsotan (GSFC/UMBC), R. Caputo (GSFC), M. Stamatikos (OSU) (i.e. the Swift-BAT team): Using the data set from T-239 to T+963 sec from the recent telemetry downlink, we report further analysis of BAT GRB 220826A (trigger #1121751) (Caputo et al., GCN Circ. 32484). The BAT ground-calculated position is RA, Dec = 206.421, -44.036 deg which is RA(J2000) = 13h 45m 41.0s Dec(J2000) = -44d 02' 10.1" with an uncertainty of 1.1 arcmin, (radius, sys+stat, 90% containment). The partial coding was 92%. The mask-weighted light curve shows a multi-peaked structure that starts at ~T0 and ends at ~T+13 s. There are roughly three main peaks at ~T+1 s, ~T+7 s, and ~T+11 s. respectively. T90 (15-350 keV) is 11.14 +- 1.02 sec (estimated error including systematics). The time-averaged spectrum from T-0.20 to T+13.01 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.44 +- 0.10. The fluence in the 15-150 keV band is 1.2 +- 0.1 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+6.58 sec in the 15-150 keV band is 2.6 +- 0.2 ph/cm2/sec. 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/1121751/BA/
GCN 32500 table
GRB_name GRB220826A
GCN_number 32500
Detection_method Konus-Wind Det
Circular_text TITLE: GCN CIRCULAR NUMBER: 32500 SUBJECT: Konus-Wind detection of GRB 220826A DATE: 22/08/29 17:46:51 GMT FROM: Dmitry Frederiks at Ioffe Institute D. Frederiks, A.Lysenko, A. Ridnaya, D. Svinkin, A. Tsvetkova, M. Ulanov, and T. Cline, on behalf of the Konus-Wind team, report: The long GRB 220826A (Swift detection: Caputo et al., GCN 32484; Fermi GBM observation: Veres & Meegan, GCN 32495) was detected by Konus-Wind (KW) in the waiting mode. A Bayesian block analysis of the KW waiting mode data in the 20-400 keV band reveals a >10 sigma count rate increase in the interval from T0-0.525 s to T0+37.747 s where T0 = T0(BAT) = 11:55:21.742 UT. The KW light curve of this burst is available at http://www.ioffe.ru/LEA/GRBs/GRB220826A/ Modeling a time-integrated spectrum of the burst by a power law with exponential cutoff (CPL) model dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep) yields alpha = -0.48 (-0.22, + 0.25) and Ep = 113(-4,+4) keV. In the 10 keV -10 MeV band, standard for the KW analysis, the burst fluence is (2.53 ± 0.29)x10^-6 erg/cm^2 and the 2.944 s peak energy flux is (2.86 ± 0.18)x10^-7 erg/cm^2/s. All the quoted errors are estimated at the 68% confidence level. All the presented results are preliminary.