//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 26624 SUBJECT: GRB 200101A: Fermi GBM Final Real-time Localization DATE: 20/01/01 20:49:47 GMT FROM: Fermi GBM Team at MSFC/Fermi-GBM The Fermi GBM team reports the detection of a likely LONG GRB At 20:39:26 UT on 1 Jan 2020, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 200101A (trigger 599603971.45143 / 200101861). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 257.4, Dec = -35.1 (J2000 degrees, equivalent to J2000 17h 09m, -35d 06'), with a statistical uncertainty of 1.0 degrees. The angle from the Fermi LAT boresight is 61.0 degrees. The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200101861/quicklook/glg_skymap_all_bn200101861.png The HEALPix FITS file, including the estimated localization systematic, can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200101861/quicklook/glg_healpix_all_bn200101861.fit The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200101861/quicklook/glg_lc_medres34_bn200101861.gif //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 26625 SUBJECT: GRB 200101A: BALROG localization (Fermi Trigger 599603971 / GRB 200101861) DATE: 20/01/01 21:03:40 GMT FROM: Jochen Greiner at MPE,Garching F. Kunzweiler, B. Biltzinger, F. Berlato, J. Burgess & J. Greiner (all MPE Garching) report: The public trigdat data of the Fermi Gamma-ray Burst Monitor (GBM) trigger 599603971 at 20:39:26 on 01 Jan. 2020 were automatically fitted for spectrum and sky location with BALROG (Burgess et al. 2018, MNRAS 476, 1427; Berlato et al. 2019, ApJ 873, 60). The best-fit position (1 sigma statistical errors) is: RA(2000.0) = 259.1+/-0.4 deg Decl.(2000.0) = -32.7+/-0.4 deg We estimate an additional systematic error of 1 deg. Further details are available at: https://grb.mpe.mpg.de/grb/GRB200101861/ The Healpix map can be downloaded from: https://grb.mpe.mpg.de/grb/GRB200101861/healpix The location parameters are available as JSON at: https://grb.mpe.mpg.de/grb/GRB200101861/json //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 26627 SUBJECT: GRB 200101A: Fermi GBM detection DATE: 20/01/02 03:23:50 GMT FROM: Peter Veres at UAH P. Veres and C. Meegan (both UAH) report on behalf of the Fermi GBM Team: "At 20:39:26.45 UT on 1 January 2020, the Fermi Gamma-Ray Burst Monitor (GBM) triggered and located GRB 200101A (trigger 599603971 / 200101861). The location for this GRB was reported in the Fermi GBM Final Real-time Localization GCN (GCN 26624). The GBM light curve shows of multiple pulses with a duration (T90) of about 10 s (50-300 keV). The time-averaged spectrum from T0+3.3 s to T0+19.8 s is best fit by a Band function with Epeak = 595 +/- 13 keV, alpha = -0.82 +/- 0.01, and beta = -2.15 +/- 0.03. The event fluence (10-1000 keV) in this time interval is (9.38 +/- 0.05)E-5 erg/cm^2. The 1-sec peak photon flux measured starting from T0+11.5 s in the 10-1000 keV band is 124.8 +/- 0.6 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/" //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 26632 SUBJECT: GRB 200101A : AstroSat CZTI detection DATE: 20/01/02 17:58:05 GMT FROM: Ramkrishna Gaikwad at IUCAA/AstroSat R. Gaikwad, S. Gupta, V. Sharma, and D. Bhattacharya (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 GRB 200101A, which was also detected by Fermi GBM Final Real-time Localization (GCN #26624), Global MASTER-Net (Lipunov V. et al., GCN #26626), BALROG localization (Kunzweiler F. et al., GCN #26625) and Fermi GBM (Veres P. et al., GCN #26627). The source was clearly detected in the 40-200 keV energy range. The light curve shows multiple peak of emission with strongest peak at 2020-01-01 20:39:27.0 UT. The measured peak count rate associated with the burst is 1588 cts/s above the background in the combined data of four quadrants, with a total of 6659 cts. The local mean background count rate was 570 cts/s. Using cumulative rates, we measure a T90 of 16.69 s. In preliminary analysis, we find that 497 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: 26635 SUBJECT: IPN triangulation of GRB 200101A DATE: 20/01/03 17:19:30 GMT FROM: Anna Kozlova at Ioffe Institute K. Hurley, on behalf of the IPN, I. G. Mitrofanov, D. V. Golovin, A. S. Kozyrev, M. L. Litvak, and A. B. Sanin, on behalf of the HEND-Odyssey GRB team, A. Ridnaia, S. Golenetskii, R. Aptekar, D. Frederiks, D. Svinkin, and T. Cline on behalf of the Konus-Wind team, A. Goldstein, M. S. Briggs, and C. Wilson-Hodge on behalf of the Fermi GBM team, and W. Boynton, C. Fellows, K. Harshman, H. Enos, and R. Starr, on behalf of the GRS-Odyssey GRB team, report: The long-duration, extremely bright GRB 200101A (Fermi-GBM detection: The Fermi GBM team, GCN Circ. 26624; Veres and Meegan, GCN Circ. 26627; BALROG localization: Kunzweiler et al., GCN Circ. 26625; AstroSat CZTI detection: Gaikwad et al., GCN Circ. 26632) was detected by Konus-Wind, Fermi (GBM trigger 599603971), Mars-Odyssey (HEND), and AstroSat(CZTI) at about 74366 s UT (20:39:26). We have triangulated it to a preliminary, 3 sigma error box whose coordinates are: --------------------------------------------- RA(2000), deg Dec(2000), deg --------------------------------------------- Center: 258.995 (17h 15m 59s) -32.304 (-32d 18' 14") Corners: 259.549 (17h 18m 12s) -31.755 (-31d 45' 20") 258.488 (17h 13m 57s) -33.470 (-33d 28' 11") 258.436 (17h 13m 45s) -32.806 (-32d 48' 22") 259.506 (17h 18m 01s) -30.953 (-30d 57' 11") --------------------------------------------- The error box area is about 2611 sq. arcmin, and its maximum dimension is 2.7 deg (the minimum one is 21.8 arcmin). The Sun distance was about 21 deg. This box may be improved. The IPN localization is consistent with, but reduces the area of, the Fermi-GBM one. A triangulation map is posted at http://www.ioffe.ru/LEA/GRBs/GRB200101_T74367/IPN/ The Konus-Wind time history and spectrum will be given in a forthcoming GCN Circular. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 26637 SUBJECT: Konus-Wind observation of GRB200101A DATE: 20/01/05 21:44:21 GMT FROM: Anastasia Tsvetkova at Ioffe Institute A. Tsvetkova, S. Golenetskii, R.Aptekar, D. Frederiks, M. Ulanov, D. Svinkin, A. Lysenko, A. Ridnaia and T. Cline on behalf of the Konus-Wind team, report: The long-duration, hard-spectrum, very bright GRB200101A (Fermi GBM detection: Veres & Meegan, GCN 26627; AstroSat CZTI detection: Gaikwad et al., GCN 26632; IPN triangulation: Hurley et al., GCN 26635) triggered Konus-Wind at T0=74367.095 s UT (20:39:27.095). The burst light curve shows a a double-peaked structure which starts at ~T0-8.3 s and has a total duration of~81.8 s The emission is seen up to ~20 MeV. As observed by Konus-Wind, the burst had a fluence of 1.43(-0.09,+0.09)x10^-4 erg/cm2, and a 64-ms peak energy flux, measured from T0+7.776 s, of 1.12(-0.12,+0.12)x10^-4 erg/cm2/s (both in the 20 keV - 10 MeV energy range). The time-integrated spectrum of the burst (measured from T0 to T0+17.408 s) is best fit in the 20 keV - 20 MeV range by the GRB (Band) model with the following parameters: the low-energy photon index alpha = -0.74(-0.06,+0.07), the high energy photon index beta = -2.45(-0.23,+0.16), the peak energy Ep = 552(-46,+49) keV, chi2 = 103/97 dof. The spectrum near the peak count rate (measured from T0+7.680 to T0+7.936 s) is best fit in the 20 keV - 20 MeV range by the GRB (Band) model with the following parameters: the low-energy photon index alpha = -0.43(-0.15,+0.18), the high energy photon index beta = -2.06(-0.15,+0.11), the peak energy Ep = 610(-105,+124) keV, chi2 = 50/55 dof. The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB200101_T74367/ All the quoted errors are at the 90% confidence level. All the quoted values are preliminary. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 26663 SUBJECT: GRB 200101A: CALET Gamma-Ray Burst Monitor detection DATE: 20/01/08 02:32:40 GMT FROM: Valentin Pal'shin at AGU Y. Kawakubo (LSU), A. Yoshida, T. Sakamoto, V. Pal'shin, S. Sugita (AGU), K. Yamaoka (Nagoya U), S. Nakahira (RIKEN), Y. Asaoka, S. Torii (Waseda U), Y. Shimizu, T. Tamura (Kanagawa U), N. Cannady (GSFC/UMBC), M. L. Cherry (LSU), S. Ricciarini (U of Florence), P. S. Marrocchesi (U of Siena), and the CALET collaboration: The long bright GRB 200101A (Fermi-GBM detection: The Fermi GBM team, GCN Circ. 26624, Veres and Meegan, GCN Circ. 26627; BALROG localization: Kunzweiler et al., GCN Circ. 26625; AstroSat CZTI detection: Gaikwad et al., GCN Circ. 26632; IPN triangulation: Hurley, GCN Circ. 26635; Konus-Wind observation: Tsvetkova et al., GCN Circ. 26637; https://gcn.gsfc.nasa.gov/other/200101A.gcn3) triggered the CALET Gamma-ray Burst Monitor (CGBM) at 20:39:30.398 UTC on 1 January 2020. The burst signal was seen by all CGBM detectors. Because of a server problem no CGBM GCN notice was automatically distributed for this event. The burst light curve shows the main emission episode with two multi-peaked pulses which starts at T-8.0 sec, peaks at T+8.0 sec and ends at T+16.8 sec, followed by a weak pulse at ~T0+75 sec.The T90 and T50 durations measured by the SGM data are 15.4 +- 12.0 sec and 1.5 +- 0.1 sec (40-1000 keV), respectively. The ground processed light curve is available at http://cgbm.calet.jp/cgbm_trigger/ground/1261946195/ The CALET data used in this analysis are provided by the Waseda CALET Operation Center located at the Waseda University.