//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23769 SUBJECT: GRB 190123A: Swift detection of a burst DATE: 19/01/23 12:32:59 GMT FROM: Kim Page at U.of Leicester A. D'Ai (INAF-IASFPA), D. N. Burrows (PSU), J.D. Gropp (PSU), N. P. M. Kuin (UCL-MSSL), K. L. Page (U Leicester) and M. H. Siegel (PSU) report on behalf of the Neil Gehrels Swift Observatory Team: At 12:19:13 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 190123A (trigger=885314). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 53.229, +45.484 which is RA(J2000) = 03h 32m 55s Dec(J2000) = +45d 29' 02" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a single-peaked structure with a duration of about 20 sec. The peak count rate was ~1400 counts/sec (15-350 keV), at ~4 sec after the trigger. The XRT began observing the field at 12:21:10.4 UT, 117.3 seconds after the BAT trigger. Using promptly downlinked data we find a bright, uncatalogued X-ray source located at RA, Dec 53.22071, 45.52425 which is equivalent to: RA(J2000) = 03h 32m 52.97s Dec(J2000) = +45d 31' 27.3" with an uncertainty of 4.0 arcseconds (radius, 90% containment). This location is 146 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 http://www.swift.ac.uk/sper. We cannot determine whether the source is fading at the present time. No spectrum from the promptly downlinked event data is yet available to determine the column density. The initial flux in the 2.5 s image was 7.12e-10 erg cm^-2 s^-1 (0.2-10 keV). UVOT took a finding chart exposure of 125 seconds with the White filter starting 124 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 extinction. Burst Advocate for this burst is A. D'Ai (antonino.dai AT gmail.com). 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/too.html.) //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23770 SUBJECT: GRB 190123A: MASTER Global Robotic Net optical observation DATE: 19/01/23 13:27:41 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, V.Kornilov, E. Gorbovskoy, N.Tiurina, P.Balanutsa, D.Vlasenko, V.Vladimirov, A.Kuznetsov, D.Kuvshinov, A.Chasovnikov (Lomonosov Moscow State University,SAI, Physics Department), O. Gres, N.M. Budnev, (Applied Physics Institute of Irkutsk State University) V. Yurkov, A. Gabovich, Yu. Sergienko, D. Kobcev (Blagoveschensk Educational State University) R. Rebolo, M. Serra, N. Lodieu, G. Israelian, L. Suarez-Andres (The Instituto de Astrofisica de Canarias) D. Buckley (South African Astronomical Observatory) A. Tlatov, V.Senik, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory) R. Podesta, C. Lopez, C.Francile, F. Podesta Observatorio Astronomico Felix Aguilar (OAFA) H. Levato (Instituto de Ciencias Astronomicas, de la Tierra y del Espacio ICATE) MASTER-Tunka robotic telescope (MASTER Global Robotic Net http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, v.2010, 30L) located in Russia (Applied Physics Institute, Irkutsk State University) was pointed to the GRB190123A 17 sec after notice time (66 sec after trigger time) at 2019-01-23 12:20:25 UT. On our first (10s exposure) image we don't find optical transient within SWIFT-XRT error-box ( A. D'Ai et al. GCN 23769 RA,Dec(2000)=03h 32m 52.97s +45d 31' 27.3" r=4") up to 16.7 unfiltered magnitude limit (5-sigma) The galactic latitude b = -8 deg., longitude l = 151 deg. The observations made on zenit distance = 7 deg. The Moon altitude is -1 deg. (92 % bright part) The sun altitude is -24.7 deg. MASTER-Amur robotic telescope ocated in Russia (Blagoveshchensk State Pedagogical University) was pointed to the GRB190123A 27 sec after notice time (77 sec after trigger time) at 2019-01-23 12:20:35 UT. On our first (10s exposure, mlim=16.3 (5-sigma)) image we don't find optical transient within SWIFT-XRT error-box. The observations made on zenit distance = 15 deg. The moon (92 % bright part) is 14 deg. above the horizon. The sun altitude is -40.1 deg. The message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23771 SUBJECT: GRB 190123A: Enhanced Swift-XRT position DATE: 19/01/23 14:07:26 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 80 s of XRT Photon Counting mode data and 1 UVOT images for GRB 190123A, 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 = 53.22060, +45.52531 which is equivalent to: RA (J2000): 03h 32m 52.94s Dec (J2000): +45d 31' 31.1" 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: 23772 SUBJECT: GRB 190123A: BOOTES-4/MET optical limit DATE: 19/01/23 14:11:37 GMT FROM: Alberto Castro-Tirado at Inst.de Astro. de Andalucia Y.-D. Hu, X.-Y.Li, E. Fernandez-Garcia, A. Ayala, A. J. Castro-Tirado (IAA-CSIC), C. Perez del Pulgar, A. Castellon, I. Carrasco (Univ. de Malaga),  S. Guziy (Univ. of Nikolaev) and D. Xiong, Y. Fan, X. Zhao, J. Bai, C. Wang, Y. Xin (Yunnan Nacional Astronomical Observatory) on behalf of a larger collaboration, report: "Following the detection of GRB 190123A by Swift (D'Ai et al. GCNC 23769), the 0.6m BOOTES-4/MET robotic telescope at Lijiang Astronomical Observatory (China) gathered images starting at 12:36 UT (~0.29 hr after trigger). No optical afterglow is found down to 20.9 mag (unfiltered images) within the Swift/XRT error box, consistent with the non-detections by Swift/UVOT (D'Ai et al. GCNC 23769) or MASTER (Lipunov et al. GCNC 23770). Observations are ongoing." //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23773 SUBJECT: GRB 190123A: Fermi GBM observation DATE: 19/01/23 17:30:47 GMT FROM: Elisabetta Bissaldi at INFN,Bari E. Bissaldi (Politecnico & INFN Bari) reports on behalf of the Fermi GBM Team: "At 12:19:18.22 UT on 23 January 2019, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 190123A (trigger 569938763 / 190123513), which was also detected by the Swift/BAT (D'Ai et al. 2019, GCN 23769). The GBM on-ground location is consistent with the Swift position. The angle from the Fermi LAT boresight at the GBM trigger time is 42 degrees. The GBM light curve consists of a multipeaked emission episode with a duration (T90) of about 17 s (50-300 keV). The time-averaged spectrum from T0-5.1 s to T0+10.8 s is adequately fit by a power law function with an exponential high-energy cutoff. The power law index is -0.68 +/- 0.25 and the cutoff energy, parameterized as Epeak, is 310 +/- 100 keV. The event fluence (10-1000 keV) in this time interval is (2.07 +/- 0.04)E-06 erg/cm^2. The 1-sec peak photon flux measured starting from T0+7.1 s in the 10-1000 keV band is 1.8 +/- 0.2 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog." //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23774 SUBJECT: GRB 190123A: GOTO optical limit DATE: 19/01/23 22:41:39 GMT FROM: Danny Steeghs at U.of Warwick/GOTO D.Steeghs, J.Lyman, K.Ulaczyk (U. Warwick), G.Ramsay (Armagh O.), M.Dyer (U. Sheffield), A.Obradovic, K. Ackley, D.K. Galloway, E.Rol (Monash U.), K. Wiersema, B.Gompertz, A.Levan, R.Cutter (U. Warwick), V.Dhillon (U. Sheffield), P.O'Brien, R.Starling (U. Leicester), S.Poshyachinda (NARIT), D.Pollacco (U. Warwick), E.Thrane (Monash U.), E.Palle (IAC) report on behalf of the GOTO collaboration: In response to GRB 190123A (D'Ai et al. GCN Circ. 23769), the Gravitational-wave Optical Transient Observer (GOTO) observed the field covering the Swift BAT/XRT positions. Observations started at 2019-01-23T19:51:53 (7.54 hours post burst) consisting of a set of 5x120s exposures in our wide L filter (400-700nm). In line with other reports (Hu et al. GCN 23772; Lipunov et al. GCN 23770), no optical source g<21.0 is visible at the updated XRT position (Beardmore et al. GCN 23771), based on PS1 and SDSS calibrators. GOTO is operated at the La Palma observing facilities of the University of Warwick on behalf of a consortium including the University of Warwick, Monash University, Armagh Observatory, the University of Leicester, the University of Sheffield, the National Astronomical Research Institute of Thailand (NARIT) and the Instituto de Astrofisica de Canarias (IAC) (https://goto-observatory.org/) //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23775 SUBJECT: GRB 190123A: Swift-XRT refined Analysis DATE: 19/01/24 01:25:27 GMT FROM: Phil Evans at U of Leicester A. Tohuvavohu (PSU), S. J. LaPorte (PSU), J.A. Kennea (PSU), P.A. Evans (U. Leicester), J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), A. Melandri (INAF-OAB), P. D'Avanzo (INAF-OAB), V. D'Elia (ASDC) and A. D'Ai report on behalf of the Swift-XRT team: We have analysed 8.3 ks of XRT data for GRB 190123A (D'Ai et al. GCN Circ. 23769), from 123 s to 33.3 ks after the BAT trigger. The data comprise 41 s in Windowed Timing (WT) mode with the remainder in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Beardmore et al. (GCN Circ. 23771). The light curve can be modelled with a power-law decay with a decay index of alpha=1.28 (+0.06, -0.05). A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 1.8 (+0.5, -0.4). The best-fitting absorption column is 2.3 (+0.9, -0.7) x 10^22 cm^-2, in excess of the Galactic value of 4.4 x 10^21 cm^-2 (Willingale et al. 2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 7.0 x 10^-11 (1.3 x 10^-10) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Total column: 2.3 (+0.9, -0.7) x 10^22 cm^-2 Galactic foreground: 4.4 x 10^21 cm^-2 Excess significance: 4.3 sigma Photon index: 1.8 (+0.5, -0.4) If the light curve continues to decay with a power-law decay index of 1.28, the count rate at T+24 hours will be 1.2 x 10^-3 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 8.6 x 10^-14 (1.6 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/00885314. This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23777 SUBJECT: GRB 190123A: GMG observational limit DATE: 19/01/24 05:53:15 GMT FROM: Jirong Mao at Yunnan Obs J. Mao, L.-F. Xing, M. Xiao, J.-M. Bai (YNAO) report: We observed the field of GRB 190123A (D'Ai et al. GCN Circ. 23769) with the 2.4-meter optical telescope at Gao-Mei-Gu (GMG) station of Yunnan Observatories. The observation began at UT 13:15:51, 23, Jan, 2019, about 1 hour after the trigger. We did not detect any source within the Swift-XRT error circle down to a magnitude of R~22.7. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23778 SUBJECT: GRB190123A: MITSuME Akeno optical upper limits DATE: 19/01/24 10:11:22 GMT FROM: Kazuki Shiraishi at Tokyo Institute of Technology K. Shiraishi, K. L. Murata, R. Itoh, Y. Tachibana, S. Harita, K. Morita, K. Iida, M. Niwano, R. Adachi, M. Oeda, Y. Yatsu, and N. Kawai (Tokyo Tech) report on behalf of the MITSuME collaboration We searched for the optical counterpart of GRB 190123A (A. D'Ai et al., GCN #23769) with the optical three color (g', Rc, and Ic) CCD cameras attached to the MITSuME 50 cm telescope at Akeno Observatory,Yamanashi, Japan. The observation started on 12:20:56 UT which corresponds to 103 sec after the trigger. We did not find any new point source within the enhanced XRT circle D’Ai et al., GCN #23769; A.P. Beardmore et al., GCN #23771) in all three bands. We obtained following 5 sigma limits for the magnitudes. T0+[sec] MID-UT T-EXP[sec] g' Rc Ic ------------------------------------------------------------------------------------------------------- 103 12:25:31 540 >18.2 >17.8 >17.0 723 12:35:51 540 >17.9 >17.7 >17.6 1,764 14:21:35 10,800 >18.4 >18.2 >17.4 ------------------------------------------------------------------------------------------------------- T0+ : Elapsed time after the burst T-EXP: Total Exposure time We used UCAC-4 catalog for flux calibration. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23780 SUBJECT: GRB 190123A: Swift-BAT refined analysis DATE: 19/01/24 12:20:11 GMT FROM: Hans Krimm at NSF/NASA-GSFC A. Y. Lien (GSFC/UMBC), S. D. Barthelmy (GSFC), J. R. Cummings (CPI), A. D'Ai (INAF-IASFPA), H. A. Krimm (NSF/USRA), 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 190123A (trigger #885314) (D'Ai, et al., GCN Circ. 23769). The BAT ground-calculated position is RA, Dec = 53.175, 45.505 deg, which is RA(J2000) = 03h 32m 42.0s Dec(J2000) = +45d 30' 16.3" with an uncertainty of 1.7 arcmin, (radius, sys+stat, 90% containment). The partial coding was 64%. The mask-weighted light curve shows a single FRED-shaped peak from about T-5 to T+20 sec, with a peak around T+3 sec. Observations were discontinued due to an observing constraint at ~T+325 sec. T90 (15-350 keV) is 24.4 +- 4.3 sec (estimated error including systematics). The time-averaged spectrum from T-1.22 to T+28.06 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.13 +- 0.23. The fluence in the 15-150 keV band is 8.4 +- 1.1 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T+4.82 sec in the 15-150 keV band is 1.0 +- 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/885314/BA/ //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23781 SUBJECT: GRB 190123A: COATLI Optical Observations DATE: 19/01/24 12:51:10 GMT FROM: Alan M. Watson at Instituto de Astronomia UNAM Alan M. Watson (UNAM), Nat Butler (ASU), Rosa L. Becerra (UNAM), Diego González (UNAM), William H. Lee (UNAM), Margarita Pereyra (UNAM), Carlos Román-Zúñiga (UNAM), Alexander Kutyrev (GSFC), and Eleonora Troja (GSFC) report: We observed the field of GRB 190123A (D'Ai et al., GCN Circ. 23769) with the COATLI 50-cm telescope and interim imager at the Observatorio Astronómico Nacional on the Sierra de San Pedro Mártir (http://coatli.astroscu.unam.mx) from 2019-01-24 02:30 to 2019-01-23 10:56 (from 14.2 to 22.6 hours after the trigger), obtaining a total of 6.7 hours of exposure in the w filter. We do not detect a source at the enhanced XRT position (Beardmore et al., GCN Circ. 23771) to a 5-sigma upper limit of w > 22.9. Our w magnitudes are calibrated against the USNO-B1 catalog (adjusted to an approximate AB system) and are not corrected for Galactic extinction in the direction of the GRB. Our deeper non-detection follows non-detections reported by Lipunov et al. (GCN Circ. 23770), Hu et al. (GCN Circ. 23772), Steeghs et al. (GCN Circ. 23774), and Shiraishi et al.(GCN Circ. 23778). We thank the COATLI technical team and the staff of the Observatorio Astronómico Nacional. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23784 SUBJECT: GRB 190123A: Swift/UVOT Upper Limits DATE: 19/01/24 14:44:09 GMT FROM: Mike Siegel at PSU/Swift MOC M. H. Siegel (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 190123A 124 s after the BAT trigger (D'Ai et al., GCN Circ. 23769). No optical afterglow consistent with the XRT position (Beardmore et al. GCN Circ. 23771) 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 124 250 123 >20.3 white 124 10248 1258 >22.0 v 3470 11721 947 >20.3 b 4290 5926 393 >21.1 u 4085 5721 393 >21.0 w1 3880 5516 393 >20.1 m2 3675 5310 393 >19.9 w2 4701 11151 1079 >21.1 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.44 in the direction of the burst (Schlegel et al. 1998). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23786 SUBJECT: GRB 190123A: AROMA-N Optical Observation DATE: 19/01/24 14:59:31 GMT FROM: Takanori Sakamoto at AGU M. Nakamura, T. Sakamoto (AGU) We observed the field of GRB 190123A detected by Swift (D'Ai et al., GCN Circ. 23769) with the 14-inch AGU Robotic Optical Monitor for Astrophysical object - Narrow (AROMA-N) located at the Sagamihara campus of Aoyama Gakuin University. 30 images of 60 sec exposures were taken in the R filter starting from January 23 12:21:49 (UT) about 156 seconds after the trigger and stopped on January 23 12:58:25 (UT). We do not detect the optical afterglow both in the individual images and the stacked image. The estimated five sigma upper limit of the combined image (total exposure of 1800 sec) is ~17.7 mag using the USNO-B1 catalog. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23788 SUBJECT: GRB 190123A: NEXT-0.6m optical limit DATE: 19/01/24 17:11:59 GMT FROM: Dong Xu at NAOC/CAS D. Xu, Z.P. Zhu (NAOC) report on behalf of a larger collaboration We observed the field of GRB 190123A (D'Ai et al., GCN Circ. 23769) with the robotic NEXT-0.6m telescope located at Nanshan, Xinjiang, China. We obtained 3x40s, 4x60s, 3x90s R-band frames, starting at 12:20:56 UT on 2019-01-23, i.e., 103 sec after the BAT trigger. No optical afterglow consistent with the XRT position (Beardmore et al. GCN Circ. 23771) is detected in the stacked image, download a limiting magnitude of R~19.5, calibrated with the USNO-B1 catalog. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23789 SUBJECT: GRB 190123A: IKI-GRB-FuN optical upper limit DATE: 19/01/24 17:24:58 GMT FROM: Alina Volnova at SAI MSU A. Volnova (IKI), A. Pozanenko (IKI), E. Mazaeva (IKI), E. Klunko (ISTP), A. Kusakin (FAPHI), I. Reva (FAPHI), R. Inasaridze (AAO), A. Ivanov (KubSU), S. Belkin (IKI) report on behalf of IKI-GRB-FuN: We observed the field of GRB 190123A (D'Ai et al., GCN 23769) on Jan., 23 with Zeiss-1000 1-m telescope of Tien Shan Astronomical Observatory starting on 13:38:38, with MC 0.25-meter telescope of Kuban State University Astrophysical observatory starting on 15:09:35 UT, with AS-32 (0.7m) telescope of Abastumani Observatory starting on 16:12:18 UT, and with AZT-33IK telescope of Sayan observatory (Mondy) starting on 18:24:05 UT. We took several frames in R band with every listed telescope. We do not detect any source at the enhanced XRT position (Beardmore et al., GCN 23771) in stacked images of each observatory. Preliminary photometry of AZT-33IKI observations is based on several nearby USNO-B1.0 stars: Date UT_start t-T0 Filter Exp. OT UL(3sigma) (mid, days) (s) 2019-01-23 18:24:05 0.28248 R 4980 n/d 22.5 Our non-detection is consistent with non-detections reported by Lipunov et al. (GCN 23770), Hu et al. (GCN 23772), Steeghs et al. (GCN 23774), Shiraishi et al.(GCN 23778), Watson et al. (GCN 23781), Siegel et al. (GCN 23784), and Nakamura & Sakamoto (GCN 23786).