//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23806 SUBJECT: GRB 190129A: MAXI/GSC detection DATE: 19/01/29 13:21:11 GMT FROM: Satoshi Sugita at Aoyama Gakuin U. S. Nakahira (RIKEN), S. Sugita (AGU), H. Negoro, M. Nakajima, A. Sakamaki, W. Maruyama, M. Aoki, K. Kobayashi (Nihon U.), T. Mihara, F. Yatabe, Y. Takao, M. Matsuoka (RIKEN), T. Sakamoto, M. Serino, Y. Kawakubo, T. Hashimoto, A. Yoshida (AGU), N. Kawai, M. Sugizaki, Y. Tachibana, K. Morita (Tokyo Tech), S. Ueno, H. Tomida, M. Ishikawa, Y. Sugawara, N. Isobe, R. Shimomukai, T. Midooka (JAXA), Y. Ueda, A. Tanimoto, T. Morita, S. Yamada, S. Ogawa (Kyoto U.), Y. Tsuboi, W. Iwakiri, R. Sasaki, H. Kawai, T. Sato (Chuo U.), H. Tsunemi, T. Yoneyama, K. Asakura, S. Ide (Osaka U.), M. Yamauchi, K. Hidaka, S. Iwahori (Miyazaki U.), T. Kawamuro (NAOJ), K. Yamaoka (Nagoya U.), M. Shidatsu (Ehime U.), Y. Kawakubo (LSU) report on behalf of the MAXI team: The MAXI/GSC nova alert system triggered a bright uncatalogued X-ray transient source at 12:21:40 UT on January 29, 2019. Assuming that the source flux was constant over the transit, we obtain the source position at (R.A., Dec) = (11.459 deg, -31.887 deg) = (00 45 50, -31 53 13) (J2000) with a statistical 90% C.L. elliptical error region with long and short radii of 0.16 deg and 0.15 deg, respectively. The roll angle of long axis from the north direction is 40.0 deg counterclockwise. There is an additional systematic uncertainty of 0.1 deg (90% containment radius). The X-ray flux averaged over the scan was 306 +- 37 mCrab (4.0-10.0keV, 1 sigma error). Without assumptions on the source constancy,we obtain a rectangular error box for the transient source with the following corners: (R.A., Dec) = (10.934, -32.736) deg = (00 43 44, -32 44 09) (J2000) (R.A., Dec) = (11.230, -32.814) deg = (00 44 55, -32 48 50) (J2000) (R.A., Dec) = (11.935, -30.870) deg = (00 47 44, -30 52 12) (J2000) (R.A., Dec) = (11.645, -30.793) deg = (00 46 34, -30 47 34) (J2000) There was no significant excess flux in the previous transit at UT 10:49 with an upper limit of 20 mCrab. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23808 SUBJECT: IPN Triangulation of GRB 190129B (long/extremely bright) DATE: 19/01/29 18:28:09 GMT FROM: Dmitry Svinkin at Ioffe Institute K. Hurley, on behalf of the IPN, I. G. Mitrofanov, D. Golovin, M. L. Litvak, and A. B. Sanin, on behalf of the HEND-Odyssey GRB team, D. Svinkin, S. Golenetskii, R. Aptekar, D. Frederiks, A. Kozlova and T. Cline on behalf of the Konus-Wind team, A. von Kienlin, X. Zhang, A. Rau, V. Savchenko, E. Bozzo, and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team, and W. Boynton, C. Fellows, K. Harshman, H. Enos, and R. Starr, on behalf of the GRS-Odyssey GRB team, report: The extremely bright, long-duration GRB 190129B was detected by Konus-Wind, INTEGRAL (SPI-ACS), and Mars-Odyssey (HEND) at about 44134 s UT (12:15:34). We have triangulated it to a preliminary, 3 sigma error box whose coordinates are: --------------------------------------------- RA(2000), deg Dec(2000), deg --------------------------------------------- Center: 117.285 (07h 49m 08s) +1.257 ( +1d 15' 24") Corners: 117.253 (07h 49m 01s) +0.258 ( +0d 15' 28") 117.088 (07h 48m 21s) +0.627 ( +0d 37' 38") 117.326 (07h 49m 18s) +2.291 ( +2d 17' 26") 117.485 (07h 49m 56s) +1.896 ( +1d 53' 45") --------------------------------------------- The error box area is about 1284 sq. arcmin, and its maximum dimension is 2.034 deg (the minimum one is 12.84 arcmin). The Sun distance was about 157 deg. This box may be improved. A triangulation map is posted at http://www.ioffe.ru/LEA/GRBs/GRB190129_T44134/IPN The time history and spectrum will be given in forthcoming GCN Circulars. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23809 SUBJECT: Konus-Wind observation of extremely bright GRB 190129B DATE: 19/01/29 18:31:05 GMT FROM: Dmitry Frederiks at Ioffe Institute D. Frederiks, S. Golenetskii, R.Aptekar, A. Kozlova, A.Lysenko, D. Svinkin, A. Tsvetkova, M. Ulanov, and T. Cline, on behalf of the Konus-Wind team, report: The extremely bright, long GRB 190129B (IPN triangulation: Hurley et al., GCN 23808) triggered Konus-Wind (KW) at T0=44134.335 s UT (12:15:34.335). The light curve of the burst shows a multi-peaked pulse, which started at ~T0-10 s and had a duration of ~ 60s, which was followed by a weaker and softer pulse around ~T0+130 s. The emission is seen up to ~20 MeV. The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB190129_T44134/ As observed by Konus-Wind, the burst had a fluence of (5.59 ± 0.40)x10^-4 erg/cm2 and a 64-ms peak energy flux, measured from T0+17.344, of (1.19 ± 0.04)x10^-4 erg/cm2 (both in the 20 keV - 10 MeV energy range). The time-integrated spectrum (measured from T0 to T0+152.832 s) is best fit in the 20 keV - 20 MeV range by the GRB (Band) function with the following model parameters: the low-energy photon index alpha = -0.85 (-0.06,+0.06), the high energy photon index beta = -2.18 (-0.16,+0.11), the peak energy Ep = 561 (-53,+56) keV, chi2 = 107/97 dof. The spectrum near the peak count rate (measured from T0+17.152 s to T0+18.432 s) is best fit in the 20 keV - 20 MeV range by the GRB (Band) function with the following model parameters: the low-energy photon index alpha = -0.64 (-0.06,+0.06), the high energy photon index beta = -2.13 (-0.08,+0.07), the peak energy Ep = 717 (-62,+66) keV, chi2 = 89/77 dof. All the quoted errors are estimated at the 90% confidence level. All the presented results are preliminary. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23810 SUBJECT: GRB 190129A: Fermi GBM detection DATE: 19/01/29 21:36:58 GMT FROM: Bagrat Mailyan at UAH E. Bissaldi (Politecnico & INFN Bari), B. Mailyan (UAH) and C. Meegan (UAH) report on behalf of the Fermi GBM Team: "At 12:21:41.87 UT on 29 January 2019, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 190129A (trigger 570457306 / 190129515), which was also detected by MAXI/GSC (Nakahira et al. 2019, GCN 23806). The GBM on-ground location is consistent with the MAXI/GSC position. The angle from the Fermi LAT boresight at the GBM trigger time is 118 degrees. The GBM light curve shows/consists of a single peak with a duration (T90) of about 8.7 s (50-300 keV). The time-averaged spectrum from T0-1 s to T0+4 s is adequately fit by a power law function with an exponential high-energy cutoff. The power law index is -1.37 +/- 0.23 and the cutoff energy, parameterized as Epeak, is 78 +/- 19 keV. The event fluence (10-1000 keV) in this time interval is (9 +/- 1)E-07 erg/cm^2. The 1-sec peak photon flux measured starting from T0-0.38 s in the 10-1000 keV band is 3.7 +/- 0.3 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: 23812 SUBJECT: GRB 190129B: Tiled Swift observations DATE: 19/01/29 22:45:45 GMT FROM: Phil Evans at U of Leicester P. A. Evans (U. Leicester) reports on behalf of the Swift team: Swift has initiated a series of observations, tiled on the sky, of the IPN GRB 190129B. Automated analysis of the XRT data will be presented online at http://www.swift.ac.uk/xrt_products/TILED_GRB00076 Any uncatalogued X-ray sources detected in this analysis will be reported on this website and via GCN COUNTERPART notices. The probability of finding serendipitous sources, unrelated to the IPN event is high: any X-ray source considered to be a probable afterglow candidate will be reported via a GCN Circular after manual consideration. Details of the XRT automated analysis methods are detailed in Evans et al. (2007, A&A, 469, 379; 2009, MNRAS, 397, 1177 and 2014, ApJS, 210, 8). This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23813 SUBJECT: GRB 190129B: Swift-XRT candidate afterglow detection DATE: 19/01/30 09:11:11 GMT FROM: Andrea Melandri at INAF-OAB S. J. LaPorte (PSU), J.A. Kennea (PSU), J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), A.P. Beardmore (U. Leicester), P. D'Avanzo (INAF-OAB), V. D'Elia (ASDC), A. D'Ai (INAF-IASFPA), B. Sbarufatti (INAF-OAB/PSU) and P.A. Evans (U. Leicester) report on behalf of the Swift-XRT team: Swift-XRT has performed follow-up observations of the IPN-detected burst GRB 190129B in a series of observations tiled on the sky. The total exposure time is 6.3 ks, distributed over 14 tiles; the maximum exposure at a single sky location was 1.1 ks. The data were collected between T0+45.0 ks and T0+60.4 ks, and are entirely in Photon Counting (PC) mode. An uncatalogued X-ray source is detected and is above the RASS limit, and is therefore likely the GRB afterglow. Using 42 s of PC mode data and 1 UVOT image, we find an enhanced XRT position (using the XRT-UVOT alignment and matching UVOT field sources to the USNO-B1 catalogue): RA, Dec = 117.46104, +0.93484 which is equivalent to: RA (J2000): 07h 49m 50.65s Dec(J2000): +00d 56' 05.4" with an uncertainty of 3.0 arcsec (radius, 90% confidence). This position is about 7 arcmin from the edge of the IPN 3 sigma error box (Hurley et al., GCN Circ 23808). The light curve is consistent with a constant source of mean count rate 4.4e-01 ct/sec. A power-law fit gives an index of 1.2 (+1.6, -2.1). A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 1.8 (+/-0.4). The best-fitting absorption column is 4.7 (+2.8, -2.1) x 10^21 cm^-2, in excess of the Galactic value of 7.3 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 4.4 x 10^-11 (6.3 x 10^-11) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Total column: 4.7 (+2.8, -2.1) x 10^21 cm^-2 Galactic foreground: 7.3 x 10^20 cm^-2 Excess significance: 3.1 sigma Photon index: 1.8 (+/-0.4) The results of the XRT-team automatic analysis of the likely afterglow are at http://www.swift.ac.uk/xrt_products/TILED_GRB00076/Source1.php. The results of the full analysis of the tiled XRT observations are available at http://www.swift.ac.uk/xrt_products/TILED_GRB00076. This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23814 SUBJECT: GRB 190129B: GROND possible host candidate DATE: 19/01/30 09:30:29 GMT FROM: Jan Bolmer at MPE/Garching J. Bolmer (MPE, Garching) and H. Steinle report: We observed the field of the extremely bright GRB 190129B (detected by Konus-Wind, INTEGRAL, and Mars-Odyssey; Hurley et al., GCN #23808) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, PASP 120, 405) mounted at the 2.2 m MPG telescope at the ESO La Silla Observatory (Chile). Observations started at 07:38 UT on 30th January, around 19.5 hours after the GRB trigger. They were performed at an average seeing of 1.8" and at an average airmass of 2.1. We found a faint source at the edge of the XRT error circle reported by LaPorte et al. (GCN #23813) at: RA (J2000.0) = 07:49:50.81 DEC (J2000.0) = +00:56:03.8 with an uncertainty of 1.5" in each coordinate. This source is already visible in the the PanSTARRS images and might therefore be the host or an unrelated foreground galaxy. Based on 7.7 min of exposure in g'r'i'z', and 8.0 min in JHK, we report the following preliminary AB magnitudes: g < 23.0 mag r = 22.7 +/- 0.3 mag i = 21.8 +/- 0.3 mag z = 21.7 +/- 0.4 mag J = 20.4 +/- 0.4 mag H = 19.1 +/- 0.2 mag K = 19.0 +/- 0.4 mag The above magnitudes are calibrated against SDSS and 2MASS and are not corrected for the expected Galactic foreground extinction corresponding to a reddening of E_(B-V)=0.08 in the direction of the burst (Schlafly & Finkbeiner 2011). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23815 SUBJECT: GRB 190129A: CALET Gamma-Ray Burst Monitor detection DATE: 19/01/30 12:12:35 GMT FROM: Valentin Pal'shin at AGU H. Onozawa, A. Yoshida, T. Sakamoto, V. Pal'shin, S. Sugita (AGU), Y. Kawakubo (LSU), A. Tezuka, S. Matsukawa, T. Ito, H. Morita, Y. Sone (AGU), K. Yamaoka (Nagoya U), S. Nakahira (RIKEN), I. Takahashi (IPMU), Y. Asaoka, S. Ozawa, S. Torii (Waseda U), Y. Shimizu, T. Tamura (Kanagawa U), W. Ishizaki (ICRR), M. L. Cherry (LSU), S. Ricciarini (U of Florence), A. V. Penacchioni, P. S. Marrocchesi (U of Siena), and the CALET collaboration: The long GRB 190129A (MAXI/GSC detection: Nakahira et al., GCN Circ. 23806; Fermi GBM detection: Bissaldi, Mailyan & Meegan, GCN Circ. 23810) triggered the CALET Gamma-ray Burst Monitor (CGBM) at 12:55:43.519 UTC on 29 January 2019. The burst signal was seen by the HXM2 and SGM detectors. The burst light curve shows a weak pulse which starts at T-2.2 sec and ends at T+4.8 sec. The T90 and T50 durations measured by the SGM data are 6.0 +- 2.2 sec and 3.0 +- 2.2 sec (40-1000 keV), respectively. The ground processed light curve is available at http://cgbm.calet.jp/cgbm_trigger/ground/1232801614/ The CALET data used in this analysis are provided by the Waseda CALET Operation Center located at the Waseda University. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23816 SUBJECT: GRB 190129B: MASTER Global Robotic Net optical observation DATE: 19/01/30 12:25:05 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, E. Gorbovskoy, N.Tyurina, V.Kornilov, D.Vlasenko, V.Vladimirov, D.Zimnukhov, A.Kuznetsov, P.Balanutsa, A. Chasovnikov, D.Kuvshinov (Lomonosov Moscow State University, SAI, Physics Department), R. Rebolo, M. Serra, N. Lodieu, G. Israelian, L. Suarez-Andres (The Instituto de Astrofisica de Canarias), D. Buckley (South African Astronomical Observatory), V. Yurkov, A. Gabovich, Yu. Sergienko, D. Kobcev (Blagoveschensk Educational State University), A. Tlatov, V.Senik, A.V. Parhomenko, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), O. Gress, N.M. Budnev, O.Ershova, Yu.Ishmuhametov (Applied Physics Institute, Irkutsk State University), 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-Kislovodsk robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) was pointed to Konus-Wind GRB190129B (Hurley et al. GCN23808, Frederiks et al. GCN 23809; Ttrig=2019-01-29 12:15:34.335 UT) at 2019-01-29 17:21:59UT. There is no OT at GROND (Bolmer et al. GCN23814) position inside Swift-XRT error-box (LaPorte et al. GCN 23813) RA,Dec=117.46104,+0.93484; +-3arcsec) with 5-sigma upper limit mlim=20.0 (MASTER unfiltered W=0.2B+0.8R calibrated by USNO-B1 field stars) Observations started when error-box altitude was 30.95deg. The sun altitude was -33.77 deg. MASTER-SAAO robotic telescope, located in South African Astronomical Observatory, was pointed to GRB190129B at 2019-01-29 19:09:22 UT. There is no OT inside Swift-XRT error-box and at GROND position with unfiltered mlim=21m (5-sigma upper limit 1080s exp.) Observations started when error-box altitude was 39.29. The sun altitude was -17.36. MASTER-Tavrida robotic telescope, located in Lomonosov MSU SAI Crimean astronomical station, was pointed to GRB190129B at 2019-01-29 2019-01-29 19:11:21UT. There is no OT inside Swift-XRT error-box and at GROND position with mlim=20.4 (5-sigma upper limit on 1080s exp.) Observations started when error-box altitude was 40.18 The sun altitude was -46.51 MASTER-IAC robotic telescope, located in Teide observatory (Tenerife, Canarias islands, Spain, IAC), was pointed to GRB190129B at 2019-01-29 20:57:26UT. There is no OT inside Swift-XRT error-box and at GROND position with mlim=20.3 (5-sigma upper limit on 540s exp.) Observations started when error-box altitude was 34.38 The sun altitude was -29.88. The message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23817 SUBJECT: GRB 190129B: AstroSat CZTI detection DATE: 19/01/30 14:42:38 GMT FROM: Tanazza Khanam at IUCAA T. Khanam, V. Sharma, D. Bhattacharya and A. Vibhute (IUCAA), V. Bhalerao (IIT-B), A. R. Rao (TIFR) and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration: Analysis of AstroSat CZTI data showed the detection of a long GRB 190129B, which was also detected by IPN Triangulation (Hurley K. et al., GCN Circ. 23808), Konus-Wind (Frederiks D. et al., GCN Circ 23809), Swift (Evans P. A. et al., GCN Circ 23812 and LaPorte S. J. et al., GCN Circ 23813) and GROND (Bolmer J. et al,. GCN Circ 23814). The source was clearly detected in the 40-200 keV energy range. The light curve shows multiple peaks of emission with strongest peak at 12:15;45.5 UT. The measured peak count rate is 3638 cts/s above the background in combined data of four quadrants, with a total of 29852 cts. The local mean background count rate was 601 cts/s. Using cumulative rates, we measure a T90 of 15.83 s. In preliminary analysis, we find that 2588 Compton events are associated with this event. It was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range. CZTI GRB detections are reported regularly on the payload site at http://astrosat.iucaa.in/czti/?q=grb. CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, ISAC, IUCAA, SAC and PRL. The Indian Space Research Organisation funded, managed and facilitated the project. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23818 SUBJECT: GRB 190129B: ePESSTO NTT optical observations DATE: 19/01/30 16:53:05 GMT FROM: Paolo D'Avanzo at INAF-OAB S. Piranomonte (INAF-OAR), R. Carini (INAF-OAR), P. D'Avanzo (INAF-OAB), D. Malesani (DAWN/NBI and DARK/NBI), J. Bolmer (MPE, Garching), A. Melandri (INAF-OAB), T.-W. Chen (MPE), M. Nicholl (Univ. Edinburgh), S. C. Williams (Univ. Lancaster), S. Benetti (INAF-OAPd), L. Tomasella (INAF-OAPd), A. Fiore (Univ. Padova and INAF-OAPd), C. Inserra (Cardiff), E. Kankare (Turku), K. Maguire (QUB), S. J. Smartt (QUB), O. Yaron (Weizmann), D. R. Young (QUB), I. Manulis (Weizmann) report: We observed the location of the candidate X-ray afterglow (LaPorte et al., GCN 23813) of the IPN-detected GRB 190129B (Hurley et al., GNC 23808; Frederiks et al., GCN 23809), under the extended Public ESO Spectroscopic Survey for Transient Objects (ePESSTO; see Smartt et al. 2015, A&A, 579, 40; http://www.pessto.org ). The observations were performed on the ESO New Technology Telescope (NTT) at La Silla with the EFOSC2 instrument, starting on 2019 Jan 30 at 07:12:54 UT (i.e. 18.9 hr after the burst). Two images were acquired in the r band, by 120 and 240 s, respectively. The seeing conditions were unfortunately poor (~2”). We confirm a low-S/N detection of the object visible in the Pan-STARRS images, as reported by Bolmer & Steinle (GCN 23814). Astrometry and photometry of this object are unfortunately affected by the presence of a nearby source ~2" to the SE, which is most likely a ghost from an 11-th magnitude star in the field of view. As this object is not seen in nearly-simultaneous GROND images of comparable depth (J. Bolmer, priv. comm.), we conclude that it is likely an artefact. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23819 SUBJECT: GRB 190129B: Swift/UVOT Upper Limits DATE: 19/01/30 19:55:48 GMT FROM: Paul Kuin at MSSL S.W.K. Emery (UCL-MSSL) reports on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 190129B 44980 s after the IPN-detected burst (Hurley et al. GCN Circ. 23808). No optical afterglow consistent with either the XRT position of the uncatalogued X-ray source, source 1 (LaPorte et al. GCN Circ. 23813) or the position of the GROND candidate (Bolmer et al. GCN Circ. 23814) 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 exposures at the position of source 1 are: Filter T_start(s) T_stop(s) Exp(s) Mag u 44980 60425 208 > 20.2 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.10 in the direction of the burst (Schlegel et al. 1998). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23820 SUBJECT: GRB 190129B: DDOTI Detection of the Possible Afterglow and Suggestion of Fading DATE: 19/01/30 20:32:24 GMT FROM: Alan M. Watson at Instituto de Astronomia UNAM Nat Butler (ASU), Alan M. Watson (UNAM), Rosa L. Becerra (UNAM), Diego González (UNAM), William H. Lee (UNAM), Margarita Pereyra (UNAM), Alexander Kutyrev (GSFC), Eleonora Troja (GSFC), and Tanner Wolfram (ASU) report: We observed the entire IPN error box of GRB 190129B (Hurley et al., GCN Circ. 23808) with the DDOTI/OAN wide-field imager at the Observatorio Astronómico Nacional on Sierra San Pedro Mártir (http://ddoti.astroscu.unam.mx) from 2019-01-30 02:15 UTC to 12:48 UTC (14.0 to 24.5 hours after burst) obtaining a total of 4.4 hours exposure in the w filter. If we split our exposures roughly in two, in the first half from 02:15 to 05:40 UTC we clearly detect a faint source close to the error region for the candidate XRT afterglow (LaPorte et al., GCN Circ. 23813) at 07:49:50.82 +00:56:06.1 J2000 (+/- 0.5 arcsec). In the second half from 05:41 to 12:48 UTC, this source is not visible. The presence of a nearby bright star complicates photometry. However, in the difference image we measure a magnitude and 1-sigma error of w = 22.7 +/- 1.0. 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. We assume this source corresponds to the sources reported previously by Bolmer & Steinle (GCN Circ. 23814) and Piranomonte et al. (GCN Circ. 23818) at a similar position and magnitude. However, our observations are the first to suggest fading, albeit at low significance. We thank the DDOTI technical team and the staff of the Observatorio Astronómico Nacional. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23821 SUBJECT: GRB 190129B: GOTO optical observations DATE: 19/01/30 22:22:59 GMT FROM: Danny Steeghs at U.of Warwick/GOTO D.Steeghs, A.Levan, 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, J.Lyman, 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: The Gravitational-wave Optical Transient Observer (GOTO) observed the IPN region of GRB 190129B (Hurley et al., GCN Circ. 23808), between 2019-01-29T21:07:31 and 2019-01-30T02:41:31 with several sets of 5x120s exposures in our wide L filter (400-700nm). No viable counterpart is detected within or near the 3-sigma error region of Hurley et al. down to a 5-sigma detection limit of g=20.9. Our limits are consistent with those reported in Lupinov et al. (GCN 23816) at around the same delta since the burst. We see no evidence for the source candidates reported by Bolmer et al. (GCN 23814), Piranomonto et al. (GCN 23818) and Butler et al. (GCN 23820). 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: 23822 SUBJECT: Improved IPN error box for GRB 190129B DATE: 19/01/30 22:42:18 GMT FROM: Dmitry Svinkin at Ioffe Institute K. Hurley, on behalf of the IPN, I. G. Mitrofanov, D. Golovin, M. L. Litvak, and A. B. Sanin, on behalf of the HEND-Odyssey GRB team, D. Svinkin, S. Golenetskii, R. Aptekar, D. Frederiks, A. Kozlova and T. Cline on behalf of the Konus-Wind team, A. von Kienlin, X. Zhang, A. Rau, V. Savchenko, E. Bozzo, and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team, and W. Boynton, C. Fellows, K. Harshman, H. Enos, and R. Starr, on behalf of the GRS-Odyssey GRB team, report: Using the updated Mars-Odyssey (HEND) data we have triangulated this GRB to an improved, but still preliminary, 3 sigma error box whose coordinates are: --------------------------------------------- RA(2000), deg Dec(2000), deg --------------------------------------------- Center: 117.441 (07h 49m 46s) +0.895 ( +0d 53' 42") Corners: 117.395 (07h 49m 35s) -0.055 ( +0d 03' 17") 117.262 (07h 49m 03s) +0.238 ( +0d 14' 18") 117.494 (07h 49m 58s) +1.875 ( +1d 52' 31") 117.623 (07h 50m 30s) +1.563 ( +1d 33' 46") --------------------------------------------- The error box area is about 1022 sq. arcmin, and its maximum dimension is 1.932 deg (the minimum one is 10.3 arcmin). The Sun distance was about 157 deg. This error box doesn't overlap the initial error box (Hurley et al., GCN Circ. 23808), the distance between box centers is 23.65 arcmin. The distance between the improved box center and the Swift-XRT candidate afterglow (LaPorte et al., GCN Circ. 23813) is 2.68 arcmin, supporting the association of the transient and the GRB. This box may be further improved. A triangulation map is posted at http://www.ioffe.ru/LEA/GRBs/GRB190129_T44134/IPN We apologize for any inconvenience caused. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23824 SUBJECT: GRB 190129B: Insight-HXMT/HE detection DATE: 19/01/31 11:28:42 GMT FROM: QiBin Yi at IHEP, HXMT Q. B. Yi, C. K. Li, X. B. Li, G. Li, J. Y. Liao, S. L. Xiong, C. Z. Liu, X. F. Li, Z. W. Li, Z. Chang, X. F. Lu, J. L. Zhao, A. M. Zhang, Y. F. Zhang, C. L. Zou (IHEP), Y. J. Jin, Z. Zhang (THU), T. P. Li (IHEP/THU), L. M. Song, M. Wu, Y. P. Xu, S. N. Zhang (IHEP), report on behalf of the Insight-HXMT team: At 2019-01-29T12:15:31.000 (T0), the Insight-HXMT/HE detected GRB 190129B (trigger ID: HEB190129510) in a routine search of the data, which was also triggered by IPN (Hurley et al., GCN 23808) and Konus-Wind (Frederiks et al., GCN 23809) The Insight-HXMT/HE light curve mainly consists of multiple pulses with a duration (T90) of 10.1 s measured from T0+8.10 s. The 1-s peak rate, measured from T0+14.07 s, is 18437.6 cnts/s. The total counts from this burst is 126004.0 counts. URL_LC: http://www.hxmt.org/images/GRB/HEB190129510_lc.jpg All measurements above are made with the CsI detectors operating in the regular mode with the energy range of about 80-800 keV (record energy). Only gamma-rays with energy greater than about 200 keV can penetrate the spacecraft and leave signals in the CsI detectors installed inside of the telescope. Insight-HXMT is the first Chinese space X-ray telescope, which was fundedjointly by the China National Space Administration (CNSA) and the Chinese Academy of Sciences (CAS). More information could be found at: http://www.hxmt.org.