GRB210722A

This page lists all entries on GRB210722A in GRBweb

Summary Fermi GBM IPN Swift GCN 30475 GCN 30476 GCN 30478 GCN 30480 GCN 30481 GCN 30482 GCN 30483 GCN 30484 GCN 30487 GCN 30488 GCN 30489 GCN 30490 GCN 30492 GCN 30494 GCN 30504 GCN 30505 GCN 31754

Summary table
Variable Value Source
GRB_name_Fermi GRB210722871
T0 20:54:40.363 UTC Fermi_GBM
ra 27.0303° Swift
decl -6.3472° Swift
pos_error 9.58e-05° Swift
T90 61.953 s Fermi_GBM
T90_error 11.337 s Fermi_GBM
T90_start 20:54:40.363 UTC Fermi_GBM
fluence 4.37e-06 erg/cm² Fermi_GBM
fluence_error 6.38e-08 erg/cm² Fermi_GBM
redshift 1.1450
T100 61.953 s
GBM_located False
mjd 59417.87130049768 Fermi_GBM
Fermi GBM table
GRB_name_Fermi GRB210722871
trigger_name bn210722871
ra 27.0279°
decl -6.3450°
pos_error 3.69e+00°
datum 2021-07-22
t_trigger 20:54:40.875 UTC
T90 61.953 s
T90_error 11.337 s
T90_start 20:54:40.363 UTC
fluence 4.37e-06 erg/cm²
fluence_error 6.38e-08 erg/cm²
flux_1024 3.96e+00 erg/cm²/s
flux_1024_error 3.24e-01 erg/cm²/s
flux_1024_time 2.30e+00 erg/cm²/s
flux_64 6.04e+00 erg/cm²/s
flux_64_error 1.40e+00 erg/cm²/s
IPN table
GRB_name GRB210722A
ra 27.0250°
decl -6.3500°
pos_error 5.00e-02°
redshift 1.1450
Swift table
GRB_name GRB210722A
t_trigger 20:54:42 UTC
ra 27.0303°
decl -6.3472°
pos_error 9.58e-05°
GCN 30475 table
GRB_name GRB210722A
GCN_number 30475
Detection_method Swift Det
t_trigger 20:54:42 UTC
ra 27.0230°
decl -6.3540°
Circular_text TITLE: GCN CIRCULAR NUMBER: 30475 SUBJECT: GRB 210722A: Swift detection of a burst with a bright optical counterpart DATE: 21/07/22 21:13:43 GMT FROM: David Palmer at LANL P. D'Avanzo (INAF-OAB), A. Y. Lien (GSFC/UMBC), F. E. Marshall (NASA/GSFC), A. Melandri (INAF-OAB), M. J. Moss (GWU), D. M. Palmer (LANL) and A. Tohuvavohu (U Toronto) report on behalf of the Neil Gehrels Swift Observatory Team: At 20:54:42 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 210722A (trigger=1061223). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 27.023, -6.354 which is RA(J2000) = 01h 48m 06s Dec(J2000) = -06d 21' 14" 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 30 sec. The peak count rate was ~1500 counts/sec (15-350 keV), at ~0 sec after the trigger. Using promptly downlinked XRT data we find an uncatalogued X-ray source located at RA, Dec 27.028, -6.345 which is equivalent to: RA(J2000) = +01h 48m 06.84 Dec(J2000) = -06d 20' 42.7" with an uncertainty of 5.0 arcseconds (radius, 90% containment). UVOT took a finding chart exposure of 150 seconds with the White filter starting 94 seconds after the BAT trigger. There is a candidate afterglow in the rapidly available 2.7'x2.7' sub-image at RA(J2000) = 01:48:07.27 = 27.03028 DEC(J2000) = -06:20:49.8 = -6.34718 with a 90%-confidence error radius of about 0.74 arc sec. This position is 9.6 arc sec. from the center of the XRT error circle. The estimated magnitude is 14.37 with a 1-sigma error of about 0.14. No correction has been made for the expected extinction corresponding to E(B-V) of 0.027. Burst Advocate for this burst is P. D'Avanzo (paolo.davanzo AT inaf.it). 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 30476 table
GRB_name GRB210722A
GCN_number 30476
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 30476 SUBJECT: GRB 210722A: Nanshan/NEXT optical afterglow observations DATE: 21/07/22 21:58:22 GMT FROM: Dong Xu at NAOC/CAS Z.P. Zhu (NAOC, HUST), S.Y. Fu, D. Xu, X. Liu (NAOC), X. Gao (Urumqi No.1 Senior High School), J.Z. Liu (XAO) report: We observed the field of GRB 210722A (D'Avanzo et al., GCN 30475) using the NEXT-0.6m telescope located at Nanshan, Xinjiang, China. We obtained a series of 40 s, 60 s, 90 s frames in the Sloan r-band, starting at 20:56:45 UT on 2021-07-22, i.e., 123 s after the BAT trigger, among which part of the frames are useless due to the cloudy weather. An uncatalogued optical transient is detected at the Swift/UVOT position (D'Avanzo et al., GCN 30475) with varying brightness, and thus confirms it as the optical afterglow of the burst. Preliminary analysis of the beginning photometry is as follows: Tmid-T0(sec) Mag MagErr 143 14.33 0.01 361 13.94 0.01 452 14.01 0.01 All magnitudes are calibrated with the nearby PS1 field.
GCN 30478 table
GRB_name GRB210722A
GCN_number 30478
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 30478 SUBJECT: GRB 210722A: Assy optical detection DATE: 21/07/22 22:49:40 GMT FROM: Alexei Pozanenko at IKI, Moscow N. Pankov (HSE, IKI), M. Krugov (FAI), A. Pozanenko (IKI), V. Kim (FAI, Pulkovo Observatory), S. Belkin (IKI) report on behalf of GRB IKI FuN: We observed the field of GRB 210722A (D'Avanzo et al., GCN 30475) with AZT-20 telescope of Assy-Turgen observatory starting on 2021-07-22 (UT) 21:42:07. We obtained 30 frames in r' - filter before a twilight. We clearly detect the bright optical afterglow (D'Avanzo et al., GCN 30475; Zhu et al., GCN 30476) in coordinates of 01:48:07.27 -06:20:50.00 with accuracy of 0.1 arcsec in both coordinates. The coordinates are coincides with UVOT coordinates (D'Avanzo et al., GCN 30475) Preliminary photometry of the optical afterglow in the first image of 60 s exposure is following Date UT start t-T0 Exp. Filter OT Err. UL(3sigma) (mid, days) (s) (AB) 2021-07-22 21:42:07 0.03293 1*60 r' 16.20 0.03 21.1 The photometry is based on the nearby PS1 stars.
GCN 30480 table
GRB_name GRB210722A
GCN_number 30480
Detection_method Swift Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 30480 SUBJECT: Swift GRB 210722A: Global MASTER-Net observations report DATE: 21/07/23 00:11:36 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, E. Gorbovskoy, V.Kornilov, N.Tyurina, P.Balanutsa, A.Kuznetsov, F.Balakin, V.Vladimirov, D. Vlasenko, I.Gorbunov, D.Zimnukhov, V.Senik, T.Pogrosheva, D.Kuvshinov, D. Cheryasov (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, O.Ershova (Irkutsk State University, API), A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), V. Yurkov, A. Gabovich, Yu. Sergienko (Blagoveschensk Educational State University) MASTER-Tavrida robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, SAI Crimea astronomical station) was pointed to the Swift GRB 210722A ( P. D'Avanzo et al., GCN 30475) errorbox 11033 sec after notice time and 11204 sec after trigger time at 2021-07-23 00:01:26 UT, with upper limit up to 17.6 mag. The observations began at zenith distance = 68 deg. The sun altitude is -19.1 deg. The galactic latitude b = -65 deg., longitude l = 159 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=1667717 We obtain a following upper limits. Tmid-T0 | Site |Filt.| Expt. | Limit| Comment _________|_____________________|_____|_______|______|________ 11294 | MASTER-Tavrida | C | 180 | 17.6 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited.
GCN 30481 table
GRB_name GRB210722A
GCN_number 30481
Detection_method Optical
ra 27.0304°
decl -6.3472°
Circular_text TITLE: GCN CIRCULAR NUMBER: 30481 SUBJECT: GRB 210722A: GIT optical detection and preliminary analysis DATE: 21/07/23 13:44:05 GMT FROM: Harsh Kumar at Indian Inst of Tech,Bombay H. Kumar(IITB), S. Joharle (Fergusson College), J. Stanzin (IAO), V. Bhalerao(IITB), G. C. Anupama(IIA), S. Barway(IIA) report on behalf of the GIT team: We observed GRB 210722A detected by Swift Burst Alert Telescope (P. D'Avanzo et al., GCN #30475) and optical afterglow detected by P. D'Avanzo et al., GCN #30475; Z.P. Zhu et al., GCN #30476; N. Pankov et al., GCN #30477; with 0.7m GROWTH-India Telescope (GIT). We obtained multiple exposures in the g', r' filters. The image depth was shallower than usual due to weather conditions. We clearly detected the afterglow in our images at R.A.= 1:48:07.29, DEC.= -6:20:49.85, which agrees with the swift UVOT position (GCN #30475). The photometric results follow as: ------------------------------------------------------------------------ T_start - T0 (days) | Exposure (sec) | Filter | Magnitude (AB)| Notes | ------------------------------------------------------------------------ 0.014938 | 100 | g' | 15.95 +/- 0.23 | Low significance detection 0.012057 | 100 | r' | 15.11 +/- 0.08 | 0.032546 | 4x100 | r' | 16.34 +/- 0.08 | Stacked image 0.050742 | 100 | r' | 16.81 +/- 0.19 | 0.053035 | 100 | r' | 16.88 +/- 0.07 | ------------------------------------------------------------------------ Based on our observations, we found that the GRB is decaying with a power-law index of 1.14 +/- 0.03 in r' band. Our observations are in agreement with magnitudes reported by Z.P. Zhu et al., GCN #30476, and N. Pankov et al., GCN #30477. The magnitudes are calibrated against PanSTARRS (Flewelling et al., 2018) and not corrected for Galactic extinction. The GROWTH India Telescope (GIT) is a 70-cm telescope with a 0.7-degree field of view, set up by the Indian Institute of Astrophysics and the Indian Institute of Technology Bombay with support from the Indo-US Science and Technology Forum (IUSSTF) and the Science and Engineering Research Board (SERB) of the Department of Science and Technology (DST), Government of India (https://sites.google.com/view/growthindia/). It is located at the Indian Astronomical Observatory (Hanle), operated by the Indian Institute of Astrophysics (IIA).
GCN 30482 table
GRB_name GRB210722A
GCN_number 30482
Detection_method Swift-UVOT Det
ra 27.0303°
decl -6.3471°
Circular_text TITLE: GCN CIRCULAR NUMBER: 30482 SUBJECT: GRB 210722A: Swift/UVOT Detection DATE: 21/07/23 13:46:11 GMT FROM: Mike Siegel at PSU/Swift MOC M. H. Siegel (PSU) and P. D'Avanzo (INAF-OAB) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 210722A 94 s after the BAT trigger (D'Avanzo et al., GCN Circ. 30475). A source consistent with the XRT position is detected in the initial UVOT exposures. The preliminary UVOT position is: RA (J2000) = 01:48:07.28 = 27.03033 (deg.) Dec (J2000) = -06:20:49.7 = -6.34713 (deg.) with an estimated uncertainty of 0.42 arc sec. (radius, 90% confidence). Preliminary detections 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 94 244 147 14.31 +/- 0.02 v 637 656 19 14.52 +/- 0.06 b 563 583 20 14.65 +/- 0.04 u 308 557 246 13.68 +/- 0.02 w1 686 705 20 14.08 +/- 0.06 w2 4908 4971 62 17.08 +/- 0.14 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.027 in the direction of the burst (Schlegel et al. 1998).
GCN 30483 table
GRB_name GRB210722A
GCN_number 30483
Detection_method Swift-XRT Other
ra 27.0302°
decl -6.3476°
Circular_text TITLE: GCN CIRCULAR NUMBER: 30483 SUBJECT: GRB 210722A: Swift-XRT refined Analysis DATE: 21/07/23 14:27:18 GMT FROM: Phil Evans at U of Leicester K.L. Page (U. Leicester), A.P. Beardmore (U. Leicester), P.A. Evans (U. Leicester), M.G. Bernardini (INAF-OAB), E. Ambrosi (INAF-IASFPA) , M. Capalbi (INAF-IASFPA), J. D. Gropp (PSU), J.A. Kennea (PSU), A. Tohuvavohu (U. Toronto) and P. D'Avanzo report on behalf of the Swift-XRT team: We have analysed 6.3 ks of XRT data for GRB 210722A (D'Avanzo et al. GCN Circ. 30475), from 91 s to 47.1 ks after the BAT trigger. The data comprise 294 s in Windowed Timing (WT) mode with the remainder in Photon Counting (PC) mode. Using 3301 s of PC mode data and 8 UVOT images, we find an enhanced XRT position (using the XRT-UVOT alignment and matching UVOT field sources to the USNO-B1 catalogue): RA, Dec = 27.03023, -6.34758 which is equivalent to: RA (J2000): 01h 48m 07.26s Dec(J2000): -06d 20' 51.3" with an uncertainty of 2.0 arcsec (radius, 90% confidence). The late-time light curve (from T0+4.5 ks) can be modelled with a power-law decay with a decay index of alpha=1.31 (+0.10, -0.09). A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 2.20 (+/-0.05). The best-fitting absorption column is 4.2 (+1.0, -0.9) x 10^20 cm^-2, in excess of the Galactic value of 2.2 x 10^20 cm^-2 (Willingale et al. 2013). The PC mode spectrum has a photon index of 1.84 (+0.11, -0.10) and a best-fitting absorption column of 3.5 (+2.4, -1.2) x 10^20 cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.5 x 10^-11 (3.8 x 10^-11) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Total column: 3.5 (+2.4, -1.2) x 10^20 cm^-2 Galactic foreground: 2.2 x 10^20 cm^-2 Excess significance: <1.6 sigma Photon index: 1.84 (+0.11, -0.10) If the light curve continues to decay with a power-law decay index of 1.31, the count rate at T+24 hours will be 0.013 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 4.4 x 10^-13 (4.8 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/01061223. This circular is an official product of the Swift-XRT team.
GCN 30484 table
GRB_name GRB210722A
GCN_number 30484
Detection_method Swift-BAT Det
Circular_text TITLE: GCN CIRCULAR NUMBER: 30484 SUBJECT: GRB 210722A: RATIR Optical Observations DATE: 21/07/23 14:49:14 GMT FROM: Nat Butler at Az State U Nat Butler (ASU), Alan M. Watson (UNAM), Alexander Kutyrev (GSFC), William H. Lee (UNAM), Michael G. Richer (UNAM), Ori Fox (STScI), J. Xavier Prochaska (UCSC), Josh Bloom (UCB), Antonino Cucchiara (UVI), Eleonora Troja (GSFC), Owen Littlejohns (ASU), Enrico Ramirez-Ruiz (UCSC), Jesús González (UNAM), Carlos Román-Zúñiga (UNAM), Harvey Moseley (GSFC), John Capone (UMD), V. Zach Golkhou (U. Wash.), and Vicki Toy (UMD) report: We observed the field of GRB 210722A (D'Avanzo, et al., GCN 30475) with the Reionization and Transients Infrared Camera (RATIR) on the 1.5m Harold Johnson Telescope at the Observatorio Astronómico Nacional on Sierra San Pedro Mártir from 2021/07 23.40 to 2021/07 23.48 UTC (12.43 to 14.36 hours after the BAT trigger), obtaining a total of 1.22 hours exposure in the r and i bands. In comparison with the SDSS DR9 and 2MASS catalogs, we obtain the following detections of the optical afterglow: r = 19.41 +/- 0.05 i = 19.35 +/- 0.04 These magnitudes are in the AB system and are not corrected for Galactic extinction in the direction of the GRB. We thank the staff of the Observatorio Astronómico Nacional in San Pedro Mártir.
GCN 30487 table
GRB_name GRB210722A
GCN_number 30487
Detection_method Other
redshift 1.1450
Circular_text TITLE: GCN CIRCULAR NUMBER: 30487 SUBJECT: GRB 210722A: Redshift from OSIRIS/GTC DATE: 21/07/23 17:50:29 GMT FROM: C. C. Thoene at HETH/IAA-CSIC C. C. Thoene (HETH/IAA-CSIC), A. de Ugarte Postigo (HETH/IAA-CSIC, DARK/NBI), D. A. Kann, M. Blazek, J. F. Agui Fernandez (all HETH/IAA-CSIC), J. P. U Fynbo (DAWN/NBI), L. Izzo (DARK/NBI), N. R. Tanvir (U. Leicester) and N. Castro (GTC) report: We obtained spectroscopy of the afterglow of GRB 210722A (D’Avanzo et al. GCN #30475, Page et al. GCN #30483, Zhu et al. GCN #30476) with OSIRIS mounted on the 10.4 m GTC telescope at the Roque de los Muchachos observatory (La Palma, Spain). Observations started at 05:02:09 UT with a mid-time of 05:17:30 UT (8.38 hr after the burst) and consisted of 2x900s spectra taken with grism R1000B, which covers the spectral range between 3700 and 7800 AA. We also obtained an acquisition image of 60s in r'-band at 04:58:25 UT. Observing conditions were rather bad with a seeing of 1.7 arcsec and taken during morning twilight. We detect several weak absorption lines, consistent with the MgII doublet, FeII 2344, 2374, 2383, 2587 and 2600 at a common redshift of z=1.145. The lines are in the weakest 1.7% of the average GRB absorption line strength (de Ugarte Postigo et al. 2012, A&A 548, 11). The detection of the afterglow in all UVOT filters (Siegel et al. GCN #30482) is consistent with this redshift. The acquisition image shows the afterglow to be r’ = 18.92 +/- 0.03 compared to 7 SDSS field stars.
GCN 30488 table
GRB_name GRB210722A
GCN_number 30488
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 30488 SUBJECT: GRB 210722A: Kitab optical observations, light curve DATE: 21/07/23 17:59:25 GMT FROM: Alexei Pozanenko at IKI, Moscow N. Pankov (IKI, HSE), A. Zhornichenko (KIAM), A. Pozanenko (IKI), V. Agletdinov (KIAM), M. Krugov (FAI), V. Kim (FAI), S. Belkin (IKI), Sh. Ehgamberdiev (UBAI) report on behalf of IKI-GRB-FuN: We observed the field of GRB 210722A (D'Avanzo et al., GCN 30475) with Kitab-ISON RC-36 telescope in Clear filter. Observation started on July, 22 (UT) 21:31:44 and ended on July, 22 (UT) 23:20:06. We clearly detect the bright optical afterglow (D'Avanzo et al., GCN 30475; Zhu et al., GCN 30476; Pankov et al., GCN 30478; Lipunov et al., GCN 30480; Kumar et al., GCN 30481; Siegel et al., GCN 30421; Butler et al., GCN 30484). Preliminary photometry of the first and latest combined images are following Date, UT start, t-T0, Exp., Filter, OT, Err, UL(3 sigma) (mid, days) 2021-07-22 21:31:44 0.02572 5*60 CR 16.00 0.15 18.4 2021-07-22 23:13:54 0.09667 7*60 CR 17.33 0.12 19.0 The photometry is based on nearby USNO-B1.0 stars, R2 magnitude. USNO-B1.0_id R2 USNO_B10-0836-00016699 USNO_B10-0836-00016715 We approximate the light curve by single PL model with power law index of -1.1 which is corroborating with PL index reported by Kumar et al. (GCN 30481). The light curve of our observations in Assy (Pankov et al., GCN 30478) and Kitab observatory can be found at http://grb.rssi.ru/GRB210722A/GRB210722A_LC.jpeg
GCN 30489 table
GRB_name GRB210722A
GCN_number 30489
Detection_method Swift-BAT Det
ra 27.0310°
decl -6.3470°
Circular_text TITLE: GCN CIRCULAR NUMBER: 30489 SUBJECT: GRB 210722A: Swift-BAT refined analysis DATE: 21/07/23 20:37:20 GMT FROM: Amy Lien at GSFC S. D. Barthelmy (GSFC), P. D'Avanzo (INAF-OAB) H. A. Krimm (NSF), S. Laha (GSFC/UMBC), A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU), M. Stamatikos (OSU), T. N. Ukwatta (LANL) (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 210722A (trigger #1061223) (D'Avanzo et al., GCN Circ. 30475). The BAT ground-calculated position is RA, Dec = 27.031, -6.347 deg which is RA(J2000) = 01h 48m 07.4s Dec(J2000) = -06d 20' 49.9" with an uncertainty of 1.2 arcmin, (radius, sys+stat, 90% containment). The partial coding was 43%. The mask-weighted light curve shows a single-peaked structure that starts at ~T-5 s, peaks at ~T0, and ends at ~T+30 s, with some weak tail emission that lasts until ~T+60 s. T90 (15-350 keV) is 50.20 +- 10.54 sec (estimated error including systematics). The time-averaged spectrum from T-4.40 to T+59.59 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.62 +- 0.14. The fluence in the 15-150 keV band is 2.5 +- 0.2 x 10^-06 erg/cm2. The 1-sec peak photon flux measured from T+1.00 sec in the 15-150 keV band is 2.2 +- 0.5 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/1061223/BA/
GCN 30490 table
GRB_name GRB210722A
GCN_number 30490
Detection_method Fermi GBM Det
t_trigger 20:54:40.870 UTC
Circular_text TITLE: GCN CIRCULAR NUMBER: 30490 SUBJECT: GRB 210722A: Fermi GBM observation DATE: 21/07/23 21:29:26 GMT FROM: Joshua Wood at MSFC/Fermi-GBM J. Wood (NASA/MSFC) reports on behalf of the Fermi GBM Team: "At 20:54:40.87 UT on 22 July 2021, the Fermi Gamma-Ray Burst Monitor (GBM) triggered and located GRB 210722A (trigger 648680085 / 210722871) which was also detected by the Swift/BAT and Swift/XRT (P. D'Avanzo et al. 2021, GCN 30475). The GBM on-ground location is consistent with the Swift position. The GBM light curve consists of a single peak with a duration (T90) of about 62 s (50-300 keV). The time-averaged spectrum from T0-1.5 s to T0+62 s is well fit by a power law function with an exponential high-energy cutoff. The power law index is -1.1 +/- 0.1 and the cutoff energy, parameterized as Epeak, is 160 +/- 30 keV The event fluence (10-1000 keV) in this time interval is (5.8 +/- 0.6)E-06 erg/cm^2. The 1-sec peak photon flux measured starting from T0+2.3 s in the 10-1000 keV band is 4.0 +/- 0.3 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 30492 table
GRB_name GRB210722A
GCN_number 30492
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 30492 SUBJECT: GRB 210722A: D50 optical detection DATE: 21/07/24 08:40:09 GMT FROM: Martin Jelinek at Astro.Inst-AVCR,Ondrejov M. Jelinek, J. Strobl, R. Hudec, C. Polasek (ASU CAS Ondrejov) report: We observed the position of the bright GRB 210722A (D'Avanzo et al., GCN 30475; Page et a., GCN 30483; Barthelmy et al. GCN 30489; and Wood, GCN 30490) with the D50 telescope of the Astronomical Institute Ondrejov, near Prague, Czech Republic. We performed a set of 35x 60s exposures in SDSS-i' filter on July 24 from 1:20 to 2:01 UT. The optical afterglow (Zhu et al., GCN 30476; Pankov et al., GCN 30478 & 30488; Kumar et al., GCN 30481; Butler et al., GCN 30484; and Thoene et al., GCN 30487) is weakly detected in the overall combined image with the exposure mean time 28.9h after trigger. The Atlas-calibrated magnitude of the object is i' = 19.8 +/- 0.4.
GCN 30494 table
GRB_name GRB210722A
GCN_number 30494
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 30494 SUBJECT: GRB 210722A: continued Assy optical observations DATE: 21/07/24 12:10:35 GMT FROM: Alexei Pozanenko at IKI, Moscow N. Pankov (HSE, IKI), V. Kim (FAI, Pulkovo Observatory), A. Pozanenko (IKI), M. Krugov (FAI), S. Belkin (IKI) report on behalf of GRB IKI FuN: We continue observations of of the field of GRB 210722A (D'Avanzo et al., GCN 30475; Page et al., GCN 30483; Barthelmy et al. GCN 30489; Wood et al., GCN30490) with AZT-20 telescope of Assy-Turgen observatory. We obtained several frames in r' - filter starting on 21-07-23 (UT) 21:34:39. We clearly detect the bright optical afterglow (D'Avanzo et al., GCN 30475; Zhu et al., GCN 30476; Pankov et al., GCN 30478 & 30488; Kumar et al., GCN 30481; Butler et al., GCN 30484; Thoene et al., GCN 30487; Jelinek et al., GCN 30492). Preliminary photometry of the afterglow in the stacked image is following Date UT start t-T0 Exp. Filter OT Err. UL(3sigma) (mid, days) (s) (AB) 2021-07-23 21:34:39 1.03677 26*60 r' 20.37 0.07 22.5 The photometry is based on the nearby PS1 stars. The light curve can still be approximated by a single power law with a an index of -1.1.
GCN 30504 table
GRB_name GRB210722A
GCN_number 30504
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 30504 SUBJECT: GRB 210722A: Nanshan/NEXT further optical observations DATE: 21/07/25 07:56:29 GMT FROM: Dong Xu at NAOC/CAS S.Y. Fu (NAOC), Z.P. Zhu (NAOC, HUST), X. Liu, D. Xu (NAOC), X. Gao (Urumqi No.1 Senior High School), J.Z. Liu (XAO) report: We continued to observe the field of GRB 210722A (D'Avanzo et al., GCN 30475) using the NEXT-0.6m telescope located at Nanshan, Xinjiang, China. We obtained 15x200 s frames in the Sloan r-band, starting at 20:41:20 UT on 2021-07-24, i.e., 1.99 days after the burst. The previously reported optical afterglow (e.g., D'Avanzo et al., GCN 30475; Zhu et al., GCN 30476) is not detected in our stacked image, down to a limiting magnitude of r~21.0, calibrated with the nearby PanSTARRS field.
GCN 30505 table
GRB_name GRB210722A
GCN_number 30505
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 30505 SUBJECT: GRB 210722A: continued Assy optical observations DATE: 21/07/25 08:13:48 GMT FROM: Alexei Pozanenko at IKI, Moscow V. Kim (FAI, Pulkovo Observatory), A. Pozanenko (IKI), N. Pankov (HSE, IKI), M. Krugov (FAI), S. Belkin (IKI) report on behalf of GRB IKI FuN: We continue observations of of the field of GRB 210722A (D'Avanzo et al., GCN 30475; Page et al., GCN 30483; Barthelmy et al. GCN 30489; Wood et al., GCN30490) with AZT-20 telescope of Assy-Turgen observatory. We obtained several frames in r' - filter starting on 21-07-24 (UT) 21:34:39. We clearly detect the bright optical afterglow (D'Avanzo et al., GCN 30475; Zhu et al., GCN 30476; Pankov et al., GCN 30478, 30488, 30494; Kumar et al., GCN 30481; Butler et al., GCN 30484; Thoene et al., GCN 30487; Jelinek et al., GCN 30492; Fu et al., GCN 30504). Preliminary photometry of the afterglow in the stacked image is following Date UT start t-T0 Exp. Filter OT Err. UL(3sigma) (mid, days) (s) (AB) 2021-07-24 20:56:07 n/d 42*60 r' 21.3 0.2 21.7 The photometry is based on the nearby PS1 stars. The photometry is still compatible with the single power law of the afterglow light curve.
GCN 31754 table
GRB_name GRB210722A
GCN_number 31754
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 31754 SUBJECT: GRB 210722A: TAROT Reunion observatory optical light curve DATE: 22/03/13 22:11:59 GMT FROM: Alain Klotz at IRAP-CNRS-OMP A. Klotz (CNRS-OMP-IRAP), M. Fortune, R. Augerai (Universite de la Renuion), P. Thierry (AGORA), L. Eymar, S. Antier, M. Boer, A. de Ugarte Postigo (CNRS-OCA-ARTEMIS), We analyzed archive images of the SWIFT trigger 1061223 (GRB 210722A, BAT detection by D'Avanzo et al. GCN Circ. 30475, early optical ground observations by Zhu et al. GCN Circ. 30476, redshift by Thoene et al. GCN Circ. 30487) with the TAROT robotic telescope (D=18cm) located at Les Makes Observatory, Reunion Island, France. Images were acquired without any filter, camera FLI PL16803 and Takahashi Epsilon 180ED. According the reference star NOMAD-1 0836-0016935 R=12.57 we give the photometry of the GRB optical transient: t1(s) t2(s) R dmag 2170 2935 16.08 0.16 2944 4067 16.24 0.12 4074 4653 16.78 0.14 4659 5238 16.60 0.14 5244 6744 17.04 0.22 t1 and t2 are start and stop acquisition since the trigger. Magnitudes are not corrected for Galactic dust extinction.