GRB220706A

This page lists all entries on GRB220706A in GRBweb

Summary IPN Swift GCN 32329 GCN 32330 GCN 32331 GCN 32332 GCN 32333 GCN 32335 GCN 32337 GCN 32338 GCN 32339 GCN 32340 GCN 32342 GCN 32348 GCN 32351 GCN 32353

Summary table
Variable Value Source
T0 16:09:14 UTC GCN_circulars,Swift Det
ra 0.6045° Swift
decl -16.4111° Swift
pos_error 2.46e-04° Swift
GBM_located False
mjd 59766.6730787037 GCN_circulars,Swift Det
IPN table
GRB_name GRB220706A
ra 0.5875°
decl -16.3833°
pos_error 5.00e-02°
Swift table
GRB_name GRB220706A
t_trigger 16:09:14 UTC
ra 0.6045°
decl -16.4111°
pos_error 2.46e-04°
GCN 32329 table
GRB_name GRB220706A
GCN_number 32329
Detection_method Swift Det
t_trigger 16:09:14 UTC
ra 0.5870°
decl -16.3910°
Circular_text TITLE: GCN CIRCULAR NUMBER: 32329 SUBJECT: GRB 220706A: Swift detection of a burst DATE: 22/07/06 16:27:19 GMT FROM: Antonino D'Ai at IASF-PA A. D'Ai (INAF-IASFPA), E. Ambrosi (INAF-IASFPA), V. D'Elia (SSDC & INAF-OAR), J.D. Gropp (PSU), J. A. Kennea (PSU), N. J. Klingler (GSFC/UMBC/CRESSTII), S. Laha (GSFC/UMBC), F. E. Marshall (NASA/GSFC), K. L. Page (U Leicester), T. M. Parsotan (GSFC/UMBC/CRESSTII), M. H. Siegel (PSU) and M. A. Williams (PSU) report on behalf of the Neil Gehrels Swift Observatory Team: At 16:09:14 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 220706A (trigger=1114937). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 0.587, -16.391 which is RA(J2000) = 00h 02m 21s Dec(J2000) = -16d 23' 28" 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 50 sec. The peak count rate was ~1400 counts/sec (15-350 keV), at ~1 sec after the trigger. The XRT began observing the field at 16:10:57.0 UT, 102.8 seconds after the BAT trigger. Using promptly downlinked data we find an uncatalogued X-ray source located at RA, Dec 0.60368, -16.41065 which is equivalent to: RA(J2000) = 00h 02m 24.88s Dec(J2000) = -16d 24' 38.3" with an uncertainty of 3.5 arcseconds (radius, 90% containment). This location is 91 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 (2.40 x 10^20 cm^-2, Willingale et al. 2013), with an excess column of 6.6 (+4.12/-3.33) x 10^21 cm^-2 (90% confidence). UVOT took a finding chart exposure of 150 seconds with the White filter starting 107 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 0.025. Burst Advocate for this burst is A. D'Ai (antonino.dai 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 32330 table
GRB_name GRB220706A
GCN_number 32330
Detection_method Swift-XRT Other
ra 0.6046°
decl -16.4111°
Circular_text TITLE: GCN CIRCULAR NUMBER: 32330 SUBJECT: GRB 220706A: Prompt enhanced Swift-XRT position DATE: 22/07/06 16:57:59 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 220706A, we find an enhanced XRT position of the afterglow: RA, Dec: 0.60455, -16.41107 which is equivalent to: RA (J2000) = 00 02 25.09 Dec (J2000) = -16 24 39.9 with an uncertainty of 1.9 arcseconds (radius, 90% confidence). Analysis of the promptly available data is online at http://www.swift.ac.uk/sper/1114937. 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 32331 table
GRB_name GRB220706A
GCN_number 32331
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 32331 SUBJECT: GRB 220706A: Zadko observatory - Gingin optical observations DATE: 22/07/06 17:57:05 GMT FROM: Bruce Gendre at UVI B. Gendre, E. Moore, J. A. Moore, F. Panther (OzGrav-UWA), A. Klotz (IRAP-CNRS-OMP), P. Thierry (Les Makes observatory), and D. Coward (OzGrav-UWA), report: We imaged the field of GRB 220706A detected by SWIFT (trigger 1114937, D'Ai et al. GCN 32329) with the Zadko robotic telescope (D=100cm) located at the observatory - Gingin, Australia. The observations started 157.6s after the GRB trigger (123.9s after the notice). The elevation of the field increased from 18 degrees above horizon and weather conditions were good. At the position of the X-ray afterglow reported by Evans et al. (GCN 32330), we do not detect any source using a clear filter. t0+157.6s to t0+167.6s : R > 14.5 We co-added a series of long exposures: t0+1414s to t0+1962s : R > 17.0 Magnitudes were estimated with the nearby USNO-B1 stars and are not corrected for galactic dust extinction. N.B. Galactic coordinates are lon= 73.7767 lat=-74.3612 This message may be cited.
GCN 32332 table
GRB_name GRB220706A
GCN_number 32332
Detection_method Swift Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 32332 SUBJECT: Swift GRB 220706A: Global MASTER-Net observations report DATE: 22/07/06 22:45:23 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 220706A ( A. D'Ai et al., GCN 32329) errorbox 22935 sec after notice time and 22975 sec after trigger time at 2022-07-06 22:32:09 UT, with upper limit up to 18.2 mag. The observations began at zenith distance = 71 deg. The sun altitude is -80.3 deg. The galactic latitude b = -75 deg., longitude l = 76 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2023835 We obtain a following upper limits. Tmid-T0 | Site |Filt.| Expt. | Limit| Comment _________|_____________________|_____|_______|______|________ 23065 | MASTER-SAAO | C | 180 | 18.2 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited.
GCN 32333 table
GRB_name GRB220706A
GCN_number 32333
Detection_method Swift-XRT Det
ra 0.6043°
decl -16.4112°
Circular_text TITLE: GCN CIRCULAR NUMBER: 32333 SUBJECT: GRB 220706A: Enhanced Swift-XRT position DATE: 22/07/06 23:58:49 GMT FROM: Phil Evans at U of Leicester M.R. Goad, J.P. Osborne, A.P. Beardmore and P.A. Evans (U. Leicester) report on behalf of the Swift-XRT team. Using 822 s of XRT Photon Counting mode data and 1 UVOT images for GRB 220706A, 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 = 0.60427, -16.41121 which is equivalent to: RA (J2000): 00h 02m 25.03s Dec (J2000): -16d 24' 40.4" 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 32335 table
GRB_name GRB220706A
GCN_number 32335
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 32335 SUBJECT: GRB 220706A: Nanshan/NEXT optical upper limits DATE: 22/07/07 02:45:18 GMT FROM: Dong Xu at NAOC/CAS S.Q. Jiang (NAOC), Z.P. Zhu (NAOC,HUST), S.Y. Fu , X. Liu, D. Xu (NAOC), X. Gao (Urumqi No.1 Senior High School), J.Z. Liu (XAO) report: We observed the field of GRB 220706A detected by Swift (D'Ai et al., GCN 32329) using the NEXT-0.6m telescope located at Nanshan, Xinjiang, China. We obtained 7x200 s frames in the Sloan r-band and 5x200 s frames in the Sloan z-band, starting at 20:21:09 UT on 2022-07-06, i.e., 4.2 hr after the BAT trigger. No optical source is detected in our stacked images at the enhanced XRT position (Goad et al., GCN 32333), with upper limits as follows: T_mid-T0 (hr) Filter Upper limit(3-sigma) 4.41 r >20.7 4.79 z >18.8 calibrated with the nearby PanSTARRS field and not corrected for Galactic extinction.
GCN 32337 table
GRB_name GRB220706A
GCN_number 32337
Detection_method MAXI Det
t_trigger 17:33:25 UTC
ra 0.2190°
decl -16.4710°
Circular_text TITLE: GCN CIRCULAR NUMBER: 32337 SUBJECT: GRB 220706A: MAXI/GSC detection 84 minutes after the Swift Trigger DATE: 22/07/07 05:18:45 GMT FROM: Motoko Serino at Aoyama Gakuin U. M. Serino, T. Sakamoto (AGU), W. Iwakiri (Chuo U.), H. Negoro (Nihon U.), Y. Kawakubo (LSU), N. Kawai, M. Niwano, R. Hosokawa, Y. Imai, N. Ito, Y. Takamatsu (Tokyo Tech), M. Nakajima, K. Kobayashi, M. Tanaka, Y. Soejima (Nihon U.), T. Mihara, T. Kawamuro, S. Yamada, T. Tamagawa, M. Matsuoka (RIKEN), S. Sugita, H. Hiramatsu, A. Yoshida (AGU), Y. Tsuboi, J. Kohara (Chuo U.), M. Shidatsu, M. Iwasaki (Ehime U.), S. Nakahira, S. Ueno, H. Tomida, M. Ishikawa, M. Tominaga, T. Nagatsuka, T. Kurihara (JAXA), Y. Ueda, S. Ogawa, K. Setoguchi, T. Yoshitake, K. Inaba (Kyoto U.), H. Tsunemi (Osaka U.), M. Yamauchi, T. Sato, R. Hatsuda, R. Fukuoka, Y. hagiwara, Y. Umeki (Miyazaki U.), K. Yamaoka (Nagoya U.), M. Sugizaki (NAOC) report on behalf of the MAXI team: The MAXI/GSC nova alert system triggered a bright uncatalogued X-ray transient source at 17:33:25 UT on 2022 July 6 at (R.A., Dec) = (0.219 deg, -16.471 deg) (J2000) This position was consistent with GRB 220607A (GCN #32329) and the scan transit was 5051 sec after the BAT trigger time (T0). The scan was not completed because the GSC HV turned off due to the high latitude constraint. The preliminary observed flux was about 200 mCrab in the 2 - 10 keV band. The transient was also observed at the next scan transit (17:53, T0+6260s) and the flux decayed to about 60 mCrab in the same energy band. We note that Swift/XRT also detected bright X-ray flare around T0+5400s. There was no significant excess flux in the previous transit at 16:00 UT and in the third transit at 19:26 UT with an upper limit of 20 mCrab for each. Since the X-ray flaring activity of this GRB was unusual, we encourage multi-wavelength observations.
GCN 32338 table
GRB_name GRB220706A
GCN_number 32338
Detection_method Other
ra 0.6042°
decl -16.4103°
Circular_text TITLE: GCN CIRCULAR NUMBER: 32338 SUBJECT: GRB 220706A: Optical observations from NOT DATE: 22/07/07 07:06:31 GMT FROM: Antonio de Ugarte Postigo at OCA A. de Ugarte Postigo, (OCA), D.B. Malesani (Radboud Univ. and DAWN/NBI), and A. Kasikov (NOT, Aarhus Univ, Univ. of Tartu) report on behalf of a larger collaboration, We observed the field of GRB 220706A (D’Ai et al. GCN 32329) with AlFOSC on the 2.5m NOT telescope at Roque de los Muchachos Observatory (La Palma, Spain). The observation started at 04:33 UT (11.68 hrs after the burst) and consisted on 3x300s imaging in r-band and 5x200s in z-band. No new object is detected within the refined XRT error box (Evans et al. GCN 32330) in neither of the bands. The 3-signa detection limit in the r-band is 24.5 mag and 23.6 in z-band, calibrated with respect to Pan-STARRS field stars. Our non detection is consistent with previous reports (Gendre et al. GCN 32331, Lipunov et al. GCN 32332, Jiang et al. GCN 32335). We do note that there is a faint source at the Northern edge of the error box, at a distance of ~2.9“ from the centre of the XRT position, which is also marginally detected in the Pan-STARRS images, and for which we measure a magnitude of 24.1+/-0.3, with coordinates (J2000): R.A.: 00:02:25.01 Dec.: -16:24:37.0
GCN 32339 table
GRB_name GRB220706A
GCN_number 32339
Detection_method Swift-XRT Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 32339 SUBJECT: GRB 220706A, GROND observations DATE: 22/07/07 13:17:52 GMT FROM: Ana Nicuesa at TLS Tautenburg A. Nicuesa Guelbenzu, S. Klose (both TLS Tautenburg), and A. Rau (MPE Garching) report: We observed the field of GRB 220706A (DAi et al., GCN 32329) with GROND mounted at the 2.2m MPG telescope at La Silla Observatory (Chile). Observations started at a midtime of 09:40 UT on July 07, 2022, about 17.5 hours after the GRB trigger and were on target for 20 minutes. They were performed at an average seeing of 1.2 arcsec and at an airmass close to 1.0. Inside the enhanced Swift/XRT error circle (Goad et al., GCN 32333), we do not detect an optical/NIR transient in any band down to the following upper limits (AB mags; 3 sigma): g' > 25.2, r' > 24.9, i' > 24.2, J > 21.7, H > 21.0, K > 19.9. Combining the GROND optical (g'r'i') and NIR (JHK) bands, no object is detected inside the enhanced XRT error circle either. Our measurements add to previousely reported results (Gendre et al., GCN 32331; Lipunov et al., GCN 32332; Jiang et al., GCN 32335; de Ugarte-Postigo et al., GCN 32338). The source at the northern border of the enhanced XRT error circle reported by de Ugarte Postigo et al. (GCN 32338) is clearly detected in our combined gri images. At present we cannot decide whether this is a galaxy or not. The given limits are derived based on calibrating the optical images against the Pan-STARRS catalog and the JHK data against 2MASS stars. We thank Sam Kim for excellent support and for performing the observations.
GCN 32340 table
GRB_name GRB220706A
GCN_number 32340
Detection_method Swift-XRT Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 32340 SUBJECT: GRB 220706A: Swift-XRT refined Analysis DATE: 22/07/07 13:36:08 GMT FROM: Phil Evans at U of Leicester J.A. Kennea (PSU), A. Tohuvavohu (U. Toronto), A.P. Beardmore (U. Leicester), P.A. Evans (U. Leicester), J.P. Osborne (U. Leicester), T. Sbarrato (INAF-OAB), P. D'Avanzo (INAF-OAB), M.G. Bernardini (INAF-OAB), B. Sbarufatti (PSU) and A. D'Ai report on behalf of the Swift-XRT team: We have analysed 6.6 ks of XRT data for GRB 220706A (D'Ai et al. GCN Circ. 32329), from 87 s to 67.9 ks after the BAT trigger. The data comprise 578 s in Windowed Timing (WT) mode (the first 8 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 Goad et al. (GCN Circ. 32330). The late-time light curve (from T0+4.4 ks) can be modelled with a power-law decay with a decay index of alpha=1.3 (+/-0.4). A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 2.33 (+0.15, -0.14). The best-fitting absorption column is 6.0 (+/-0.8) x 10^21 cm^-2, in excess of the Galactic value of 2.4 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 3.5 x 10^-11 (7.6 x 10^-11) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Total column: 6.0 (+/-0.8) x 10^21 cm^-2 Galactic foreground: 2.4 x 10^20 cm^-2 Excess significance: 12.4 sigma Photon index: 2.33 (+0.15, -0.14) If the light curve continues to decay with a power-law decay index of 1.3, the count rate at T+24 hours will be 0.016 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 5.6 x 10^-13 (1.2 x 10^-12) erg cm^-2 s^-1. The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/01114937. This circular is an official product of the Swift-XRT team.
GCN 32342 table
GRB_name GRB220706A
GCN_number 32342
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 32342 SUBJECT: GRB 220706A: LCO Optical Upper Limits DATE: 22/07/08 01:42:44 GMT FROM: Robert Strausbaugh at U. of the Virgin Islands R. Strausbaugh (U. of the Virgin Islands), A. Cucchiara (College of Marin) report on behalf of a larger collaboration: We observed the Swift GRB 220706A (D'Ai et al., GCN 32329) field with the Siding Spring Observatory, Australia site, on July 6, from 18:15 to 18:52 (corresponding to 2.10 to 2.72 hours from the GRB trigger time) with the SDSS r and i filters. We performed a series of 3x300s exposures in i and 2x300 and 1x135 r bands (the last r-band observation was interrupted). We do not detect an optical counterpart within the XRT enhanced error region (Goad et al., GCN 32333) in either band, consistent with other non-detections (Gendre et al., GCN 32331; Lipunov et al., GCN 32332; Jiang et al., GCN 32335; de Ugarte-Postigo et al., GCN 32338; Guelbenzu et al., GCN 32339). The following upper limits are calculated using the PanSTARRS catalog as reference: r>23.0 i>22.5 We also observed with the LCO 1-m Sinistro instrument at the Teide Observatory, on Tenerife, on July 7, from 04:25 to 04:52 UT (corresponding to 12.27 to 12.72 hours from the GRB trigger time) with the SDSS r and i filters. We performed a series of 3x300s exposures in i and r bands. The following upper limits are calculated using the PanSTARRS catalog as reference: r>22.4 i>22.4 These magnitudes are not corrected for galactic extinction. R.S. is funded by NSF AST grant #1831682
GCN 32348 table
GRB_name GRB220706A
GCN_number 32348
Detection_method Swift-BAT Det
ra 0.5770°
decl -16.4110°
Circular_text TITLE: GCN CIRCULAR NUMBER: 32348 SUBJECT: GRB 220706A: Swift-BAT refined analysis DATE: 22/07/08 14:07:29 GMT FROM: Takanori Sakamoto at AGU M. Stamatikos (OSU), S. D. Barthelmy (GSFC), A. D'Ai (INAF-IASFPA), 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), T. Sakamoto (AGU), (i.e. the Swift-BAT team): Using the data set from T-240 to T+962 sec from the recent telemetry downlink, we report further analysis of BAT GRB 220706A (trigger #1114937) (D'Ai, et al., GCN Circ. 32329). The BAT ground-calculated position is RA, Dec = 0.577, -16.411 deg which is RA(J2000) = 00h 02m 18.5s Dec(J2000) = -16d 24' 38.8" with an uncertainty of 1.8 arcmin, (radius, sys+stat, 90% containment). The partial coding was 73%. The BAT mask-weighted light curve shows a bright peak starting from T-3 s to T+30 s. The weak emission is evident in the 10-s binned light curve starting from T-80 s to T+70 s. T90 (15-350 keV) is 86.9 +- 18.0 sec (estimated error including systematics). The time-averaged spectrum from T-71.84 to T+36.15 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.75 +- 0.17. The fluence in the 15-150 keV band is 1.4 +- 0.1 x 10^-06 erg/cm2. The 1-sec peak photon flux measured from T+3.72 sec in the 15-150 keV band is 0.9 +- 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/1114937/BA/
GCN 32351 table
GRB_name GRB220706A
GCN_number 32351
Detection_method Swift-UVOT Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 32351 SUBJECT: GRB 220706A: Swift/UVOT Upper Limits DATE: 22/07/08 20:06:11 GMT FROM: Sam LaPorte at PSU GRB 220706A: Swift/UVOT Upper Limits S. J. LaPorte (PSU) and A. D'Ai (INAF-IASFPA) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 220706A 107 s after the BAT trigger (D'Ai et al., GCN Circ. 32329). No optical afterglow consistent with the XRT position (Goad et al. GCN Circ. 32333) is detected in the initial UVOT exposures. Preliminary 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first finding chart (FC) exposure and subsequent exposures are: Filter T_start(s) T_stop(s) Exp(s) Mag white_FC 107 257 147 >20.5 u_FC 320 570 246 >20.0 white 107 1025 334 >20.5 b 751 771 19 >18.5 u 320 570 246 >20.0 w1 701 720 19 >17.8 m2 849 869 19 >18.6 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.025 in the direction of the burst (Schlegel et al. 1998).
GCN 32353 table
GRB_name GRB220706A
GCN_number 32353
Detection_method Swift Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 32353 SUBJECT: GRB 220706A : NICER detection of re-brightening 1 day after the Swift trigger DATE: 22/07/09 00:07:58 GMT FROM: Motoko Serino at Aoyama Gakuin U. W. Iwakiri (Chuo U.), M. Shidatsu (Ehime.U), M. Serino (AGU), K. C. Gendreau, Z. Arzoumanian (NASA/GSFC), T. Enoto, T. Mihara (RIKEN) We report on initial NICER observations of GRB 220706A (GCN #32329) carried out on 2022 July 7. The observations were carried out in two parts. The first epoch began at 01:36 UT, approximately a half-day after the Swift/BAT trigger (GCN #32329), and ended at 03:34 UT, with ~1.5 ksec of exposure across two successive orbits of the International Space Station (ISS). The lightcurve shows a slow decay: the NICER-measured X-ray flux decreased from 8 x 10-13 to 6 x 10-13 erg/cm2/s in the 0.3-10 keV band. The emission overall was soft, with hardness ratio of 0.1 between the 0.3-2.0 and 2.0-10.0 keV bands. The second epoch was from 17:08 to 22:09 UT (~1 day after the Swift/BAT detection), with 3.4 ksec exposure in total. We found re-brightening of the afterglow: the NICER average flux during the second epoch was 6.5 x 10-12 erg/cm2/s in 0.3-10 keV, with a hardness ratio of 0.6. The result suggests that the spectrum has significantly hardened compared with the first-epoch results, unlike typical GRBs. NICER will continue to monitor this source. Multi-wavelength followup observations are strongly encouraged. Note: Because the nature of the source is unknown, this message is cross-posted to ATel and GCN.