//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 31468 SUBJECT: GRB 220117B: Swift detection of a burst DATE: 22/01/17 20:18:29 GMT FROM: David Palmer at LANL A. Melandri (INAF-OAB), M. G. Bernardini (INAF-OAB), J.D. Gropp (PSU), N. J. Klingler (GSFC/UMBC/CRESSTII), A. Y. Lien (U Tampa), F. E. Marshall (NASA/GSFC), D. M. Palmer (LANL), T. M. Parsotan (GSFC/UMBC/CRESSTII), T. Sbarrato (INAF-OAB) and M. H. Siegel (PSU) report on behalf of the Neil Gehrels Swift Observatory Team: At 20:05:28 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 220117B (trigger=1093611). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 191.947, -28.744 which is RA(J2000) = 12h 47m 47s Dec(J2000) = -28d 44' 38" 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 ~1000 counts/sec (15-350 keV), at ~1 sec after the trigger. The XRT began observing the field at 20:07:04.0 UT, 95.9 seconds after the BAT trigger. XRT found a bright, uncatalogued X-ray source located at RA, Dec 191.9514, -28.7446 which is equivalent to: RA(J2000) = 12h 47m 48.34s Dec(J2000) = -28d 44' 40.6" with an uncertainty of 6.5 arcseconds (radius, 90% containment). This location is 14 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 2.5 s image was 4.69e-10 erg cm^-2 s^-1 (0.2-10 keV). UVOT took a finding chart exposure of nominal 150.000 seconds with the White filter starting 104 seconds after the BAT trigger. No credible afterglow candidate has been found in the initial data products. Data from the 2.7'x2.7' sub-image are not available at this time. 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 0.075. Burst Advocate for this burst is A. Melandri (andrea.melandri AT brera.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/) //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 31469 SUBJECT: Swift GRB 220117B: Global MASTER-Net observations report DATE: 22/01/17 20:24:34 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, T.Pogrosheva, E.Minkina, A.Chasovnikov, V.Topolev, V.Grinshpun, 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 (Irkutsk State University, API), B.L.Carrasco, J.R.Valdes,V.Chavushyan, C.J.Martinez, V.M.Patino Alvarez, M.L.H.Rodriguez (INAOE, OAGH) A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), A. Gabovich, V.Yurkov (Blagoveschensk Educational State University) MASTER-Amur robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Blagoveshchensk State Pedagogical University) was pointed to the Swift GRB 220117B ( A. Melandri et al., GCN 31468) errorbox 380 sec after notice time and 437 sec after trigger time at 2022-01-17 20:12:45 UT, with upper limit up to 12.4 mag. The observations began at zenith distance = 79 deg. The sun altitude is -29.8 deg. The galactic latitude b = 34 deg., longitude l = 303 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=1852756 We obtain a following upper limits. Tmid-T0 | Site |Filt.| Expt. | Limit| Comment _________|_____________________|_____|_______|______|________ 483 | MASTER-Amur | P/ | 90 | 12.4 | The observation and reduction will continue. The message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 31473 SUBJECT: GRB 220117B: Enhanced Swift-XRT position DATE: 22/01/18 02:07:41 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 867 s of XRT Photon Counting mode data and 3 UVOT images for GRB 220117B, 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 = 191.95292, -28.74540 which is equivalent to: RA (J2000): 12h 47m 48.70s Dec (J2000): -28d 44' 43.4" with an uncertainty of 2.3 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. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 31474 SUBJECT: GRB 220117B: MITSuME Akeno optical upper limits DATE: 22/01/18 02:45:51 GMT FROM: Naohiro Ito at Tokyo Tech N. Ito, R. Hosokawa, K. L. Murata, M. Niwano, Y. Imai, Y. Takamatsu, R. Yamaguchi, R. Noto, S. Sato, M. Takaku, Y. Yatsu, and N. Kawai (Tokyo Tech) report on behalf of the MITSuME collaboration: We observed the field of GRB 220117B (A. Melandri et al. GCN Circular #31468, V. Lipunov et al. GCN Circular #31469) with the optical three color (g', Rc, and Ic) CCD cameras attached to the MITSuME 50 cm telescope Akeno. The observation started at 2022-01-17 20:06:58 UT (1.5 minutes after Swift trigger). We stacked the images with good conditions. We did not detect any sources within the XRT error region (A. Melandri et al. GCN Circular #31468). We obtained the 5-sigma limits of the stacked images as follows. T0+[minutes] MID-UT T-EXP[sec] 5-sigma limits ------------------------------------------------------------------------------------------------ 2.9 2022-01-17 20:08:19 80 g'>16.3, Rc>16.4, Ic>15.8 28.7 2022-01-17 20:34:10 2280 g'>16.5, Rc>17.0, Ic>16.5 ------------------------------------------------------------------------------------------------ T0+ : Elapsed time after the burst T-EXP: Total Exposure time We used PS1 catalog for flux calibration. The magnitudes are expressed in the AB system. The images were processed in real-time through the MITSuME GPU reduction pipeline (Niwano et al. 2021, PASJ, Vol.73, Issue 1, Pages 4-24; https://github.com/MNiwano/Eclaire). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 31475 SUBJECT: GRB 220117B: Nanshan/NEXT optical upper limit DATE: 22/01/18 03:25:24 GMT FROM: Dong Xu at NAOC/CAS S.Y. Fu (NAOC), Z.P. Zhu (NAOC,HUST), X. Liu, S.Q. Jiang, D. Xu (NAOC), X. Gao (Urumqi No.1 Senior High School), J.Z. Liu (XAO) report: We observed the field of GRB 220117B detected by Swift (Melandri et al., GCN 31468) using the NEXT-0.6m telescope located at Nanshan, Xinjiang, China. Observations automatically started at 20:07:36 UT on 2022-01-17, i.e., 128 s after the BAT trigger, and a series of 40 s, 60 s, 90 s frames were obtained in the Sloan r-band. No uncatalogued optical transient is detected in our stacked images at the Swift-XRT position (GCN 31468), down to limiting magnitudes of r~18.5, calibrated with the nearby PanSTARRS field. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 31478 SUBJECT: GRB 220117B: Swift-XRT refined Analysis DATE: 22/01/18 09:11:37 GMT FROM: Phil Evans at U of Leicester J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), A.P. Beardmore (U. Leicester), M.G. Bernardini (INAF-OAB), E. Ambrosi (INAF-IASFPA) , M. Capalbi (INAF-IASFPA), A. Tohuvavohu (U. Toronto), B. Sbarufatti (PSU), D.N. Burrows (PSU) and A. Melandri report on behalf of the Swift-XRT team: We have analysed 6.7 ks of XRT data for GRB 220117B (Melandri et al. GCN Circ. 31468), from 88 s to 28.6 ks after the BAT trigger. The data comprise 203 s in Windowed Timing (WT) mode (the first 6 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 Evans et al. (GCN Circ. 31473). The late-time light curve (from T0+3.5 ks) can be modelled with a power-law decay with a decay index of alpha=0.79 (+/-0.09). A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 2.65 (+0.11, -0.10). The best-fitting absorption column is 4.5 (+/-0.4) x 10^21 cm^-2, in excess of the Galactic value of 7.6 x 10^20 cm^-2 (Willingale et al. 2013). The PC mode spectrum has a photon index of 2.04 (+0.19, -0.18) and a best-fitting absorption column of 3.0 (+0.8, -0.7) x 10^21 cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.6 x 10^-11 (5.4 x 10^-11) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Total column: 3.0 (+0.8, -0.7) x 10^21 cm^-2 Galactic foreground: 7.6 x 10^20 cm^-2 Excess significance: 5.2 sigma Photon index: 2.04 (+0.19, -0.18) If the light curve continues to decay with a power-law decay index of 0.79, the count rate at T+24 hours will be 0.024 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 8.8 x 10^-13 (1.3 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/01093611. This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 31483 SUBJECT: GRB 220117B: Swift/UVOT Upper Limits DATE: 22/01/18 14:15:21 GMT FROM: Alice Breeveld at MSSL-UCL A. A. Breeveld (UCL-MSSL) and A. Melandri (INAF-OAB) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 220117B 104 s after the BAT trigger (Melandri et al., GCN Circ. 31468). No optical afterglow consistent with the XRT position (Evans et al. GCN Circ. 31473) 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 104 254 147 >19.7 white 104 3930 344 >20.5 v 4141 4341 197 >19.2 b 3525 5048 281 >20.7 u 262 4957 239 >19.8 w1 4552 4752 197 >20.0 m2 4346 4546 197 >20.3 w2 3936 4136 197 >20.4 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.075 in the direction of the burst (Schlegel et al. 1998). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 31486 SUBJECT: GRB 220117B: Swift-BAT refined analysis DATE: 22/01/18 15:36:36 GMT FROM: Amy Lien at GSFC T. Parsotan (GSFC/UMBC), S. D. Barthelmy (GSFC), H. A. Krimm (NSF), S. Laha (GSFC/UMBC), A. Y. Lien (U Tampa), C. B. Markwardt (GSFC), A. Melandri (INAF-OAB), D. M. Palmer (LANL), T. Sakamoto (AGU), M. Stamatikos (OSU) (i.e. the Swift-BAT team): Using the data set from T-240 to T+717 sec from the recent telemetry downlink, we report further analysis of BAT GRB 220117B (trigger #1093611) (Melandri et al., GCN Circ. 31468). The BAT ground-calculated position is RA, Dec = 191.989, -28.762 deg which is RA(J2000) = 12h 47m 57.3s Dec(J2000) = -28d 45' 42.8" with an uncertainty of 2.7 arcmin, (radius, sys+stat, 90% containment). The partial coding was 96%. The mask-weighted light curve shows a weak structure that starts at ~T-3 s and ends at ~T+23 s. T90 (15-350 keV) is 24.37 +- 4.63 sec (estimated error including systematics). The time-averaged spectrum from T-2.73 to T+23.29 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.94 +- 0.32. The fluence in the 15-150 keV band is 2.9 +- 0.6 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T-0.13 sec in the 15-150 keV band is 0.5 +- 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/1093611/BA/ //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 31492 SUBJECT: GRB 220117B: z-band limit DATE: 22/01/18 21:55:44 GMT FROM: Daniele B Malesani at Radboud U A. Rossi (INAF/OAS), J. Palmerio (CNRS, GEPI - Paris Observatory), D. B. Malesani (Radboud Univ. and DAWN/NBI), N. R. Tanvir (Univ. Leicester), D. A. Kann (IAA/CSIC) report on behalf of the Stargate collaboration: We observed the field of GRB 220117B (Melandri et al., GCN 31468) using the acquisition camera of the X-shooter spectrograph, mounted on the ESO VLT UT3 (Melipal). A single z-band image (120 s exposure time) is available to us, taken approximately on January 18.2 UT (about 8.3 hr after the GRB). Inside the XRT position (Evans et al., GCN 31473), we detect no source down to a limiting magnitude z > 21.5 mag (AB, 3 sigma limit). We acknowledge excellent support from the ESO observing staff in Paranal, in particular Michael Abdul-Masih, Diego Parraguez, and Jonathan Smoker. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 31518 SUBJECT: GRB 220117B: TARGET optical upper limit DATE: 22/01/23 08:06:29 GMT FROM: Takanori Sakamoto at AGU Y. Koyanagi, K. Hasuda, T. Sakamoto (AGU) We observed the field of GRB 220117B detected by Swift (Melandri et al., GCN Circ. 31468) with The AGU Robotic Gravitational-wave Electromagnetic Telescope (TARGET) equipped with the Veloce RH200 (20 cm OTA) and the large format CCD camera (ATK11000) located at the Machida field of Aoyama Gakuin University. 18 images of 60 sec exposures were taken in the R filter starting from January 17 20:08:41 (UT) about 3.2 minutes after the trigger and stopped on January 17 20:41:42 (UT). We do not detect the optical afterglow both in the individual images and the stacked image at the enhanced XRT position (Evans, et al. GCN Circ. 31473). The estimated five sigma upper limit of the combined image (total exposure of 1080 sec) is ~15.3 mag using the USNO-B1 catalog.