//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 27145 SUBJECT: GRB 200219C: Fermi GBM Final Real-time Localization DATE: 20/02/20 00:07:23 GMT FROM: Fermi GBM Team at MSFC/Fermi-GBM The Fermi GBM team reports the detection of a likely LONG GRB At 23:57:10 UT on 19 Feb 2020, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 200219C (trigger 603849435.33311 / 200219998). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 264.5, Dec = 8.4 (J2000 degrees, equivalent to J2000 17h 37m, 8d 24'), with a statistical uncertainty of 1.0 degrees. The angle from the Fermi LAT boresight is 43.0 degrees. The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200219998/quicklook/glg_skymap_all_bn200219998.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/bn200219998/quicklook/glg_healpix_all_bn200219998.fit The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200219998/quicklook/glg_lc_medres34_bn200219998.gif //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 27151 SUBJECT: GRB 200219C: Fermi-LAT detection DATE: 20/02/20 07:49:00 GMT FROM: Makoto Arimoto at Tokyo Inst of Tech F. Dirirsa (Univ. of Johannesburg), M. Arimoto (Kanazawa Univ.), M. Axelsson (KTH & Stockholm Univ.), F. Longo (University & INFN Trieste), and N. Omodei (Stanford U.) report on behalf of the Fermi-LAT Collaboration: On February 19, 2020, Fermi-LAT detected high-energy emission from GRB 200219C, which was also detected by Fermi-GBM (trigger 603849435/200219998, GCN 27145). The best LAT on-ground location is found to be RA, Dec = 262.7, 10.5 (degrees, J2000) with an error radius of 0.24 deg (90% containment, statistical error only). This was 43 deg from the LAT boresight at the time of the GBM trigger: T0 = 23:57:10.3 UT. The data from the Fermi-LAT show a significant increase in the event rate after the GBM trigger that is spatially correlated with the GBM emission (2.7 degrees from the GBM position) with high significance. The photon flux above 100 MeV in the time interval 0-1500 s after the GBM trigger is 2.2 +/- 0.8 e-6 ph/cm2/s. The estimated photon index above 100 MeV is -2.1 +/- 0.3. The highest-energy photon is a 1.17 GeV event which is observed 344.6 seconds after the GBM trigger. A Swift ToO has been requested for this burst. The Fermi-LAT point of contact for this burst is Feraol Fana Dirirsa (fdirirsa@uj.ac.za). The Fermi-LAT is a pair conversion telescope designed to cover the energy band from 20 MeV to greater than 300 GeV. It is the product of an international collaboration between NASA and DOE in the U.S. and many scientific institutions across France, Italy, Japan and Sweden. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 27152 SUBJECT: GRB 200219C: Tiled Swift observations DATE: 20/02/20 12:01:20 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 Fermi/LAT GRB 200219C. Automated analysis of the XRT data will be presented online at http://www.swift.ac.uk/xrt_products/TILED_GRB00088 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 Fermi/LAT 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: 27155 SUBJECT: GRB 200219C: Fermi GBM detection DATE: 20/02/20 17:06:32 GMT FROM: Rachel Hamburg at UAH R. Hamburg (UAH), C. Meegan (UAH) and E. Bissaldi (Politecnico and INFN Bari) report on behalf of the Fermi GBM Team: "At 23:57:10.33 UT on 19 February 2020, the Fermi Gamma-Ray Burst Monitor (GBM) triggered and located GRB 200219C (trigger 603849435 / 200219998), which was also detected by Fermi-LAT (Dirirsa et al. 2020, GCN 27151). The Fermi GBM Final Real-time Localization (GCN 27145) is consistent with the LAT position. The GBM light curve shows a bright main peak followed by a weaker emission episode and has a duration (T90) of about 22 s (50-300 keV). The time-averaged spectrum from T0-0.00 s to T0+25.9 s is best fit by a power law function with an exponential high-energy cutoff. The power law index is -1.09 +/- 0.03 and the cutoff energy, parameterized as Epeak, is 199 +/- 9 keV. A Band function fits the spectrum equally well with Epeak = 181 +/- 12 keV, alpha = -1.05 +/- 0.03 and beta = -2.50 +/- 0.24. The event fluence (10-1000 keV) in this time interval is (1.87 +/- 0.04)E-05 erg/cm^2. The 1-sec peak photon flux measured starting from T0+3.7 s in the 10-1000 keV band is 24.8 +/- 0.4 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: 27156 SUBJECT: GRB 200219C: DDOTI Observations DATE: 20/02/20 18:58:16 GMT FROM: Alan M Watson at UNAM Alan M. Watson (UNAM), Eleonora Troja (GSFC/UMD), Nat Butler (ASU), William H. Lee (UNAM), Simone Dichiara (GSFC/UMD), Alexander Kutyrev (GSFC/UMD), Margarita Pereyra (UNAM), Rosa L. Becerra (UNAM), Diego Gonzalez (UNAM), and Tanner Wolfram (ASU) report: We observed the field of 200219C, detected by both Fermi/GBM (Fermi GBM Team, GCN Circ. 27145) and Fermi/LAT (Dirirsa et al., GCN Circ. 27151), with the DDOTI/OAN wide-field imager at the Observatorio Astronomico Nacional on Sierra San Pedro Martir (http://ddoti.astroscu.unam.mx) on the night of 2020-02-20 UTC. We observed from 2020-02-20 11:37 UTC to 2020-02-13 13:08 UTC (from 11.7 to 13.2 hours after the event) obtaining 72 minutes of exposure in the w filter. We calibrate our images against the APASS catalog. Our 5-sigma limiting magnitude is w = 20.4. Comparing our observations to the USNO-B1 and PanSTARRS PS1 DR2 catalogs, we detect no uncatalogued sources in the Fermi/LAT error region (Dirirsa et al., GCN Circ. 27151) to our 5-sigma limit. The Fermi/LAT error includes the probably XRT afterglow candidate (Evans et al., GCN Circ. 27152) at 17:30:02.34 +10:32:22.9 J2000 (source #2 at https://www.swift.ac.uk/xrt_products/TILED_GRB00088/). We see no evidence for an optical counterpart at this position to our 5-sigma limit. We thank the staff of the Observatorio Astronomico Nacional in San Pedro Martir. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 27157 SUBJECT: GRB 200219C: Swift-XRT afterglow detection DATE: 20/02/20 20:10:40 GMT FROM: Valerio D'Elia at ASDC D.N. Burrows (PSU), J. D. Gropp (PSU), J.A. Kennea (PSU), J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), A.P. Beardmore (U. Leicester), A. Melandri (INAF-OAB), T. Sbarrato (INAF-OAB), P. D'Avanzo (INAF-OAB) and P.A. Evans (U. Leicester) report on behalf of the Swift-XRT team: Swift-XRT has performed follow-up observations of the Fermi/LAT-detected burst GRB 200219C (Dirirsa et al. GCN Circ. 27151) in a series of observations tiled on the sky. The total exposure time is 2.4 ks, distributed over 4 tiles; the maximum exposure at a single sky location was 2.4 ks. The data were collected between T0+43.0 ks and T0+56.0 ks, and are entirely in Photon Counting (PC) mode. Two uncatalogued X-ray sources are detected, of which one ("Source 2") is above the RASS limit, and is therefore likely the GRB afterglow. Using 2417 s of PC mode data and 5 UVOT images, we find an enhanced XRT position (using the XRT-UVOT alignment and matching UVOT field sources to the USNO-B1 catalogue): RA, Dec = 262.50899, +10.53933 which is equivalent to: RA (J2000): 17h 30m 02.16s Dec(J2000): +10d 32' 21.6" with an uncertainty of 2.1 arcsec (radius, 90% confidence). This position is 12.9 arcmin from the Fermi/LAT position. The light curve is consistent with a constant source of mean count rate 1.1e-01 ct/sec. A power-law fit gives an index of 0.9 (+1.4, -1.5). A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 2.1 (+/-0.4). The best-fitting absorption column is 3.2 (+1.6, -1.4) x 10^21 cm^-2, in excess of the Galactic value of 1.2 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 3.1 x 10^-11 (4.9 x 10^-11) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Total column: 3.2 (+1.6, -1.4) x 10^21 cm^-2 Galactic foreground: 1.2 x 10^21 cm^-2 Excess significance: 2.4 sigma Photon index: 2.1 (+/-0.4) The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00020973. The results of the full analysis of the tiled XRT observations are available at https://www.swift.ac.uk/xrt_products/TILED_GRB00088. This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 27161 SUBJECT: GRB 200219C: Nanshan/NEXT optical upper limit and possible host galaxy from PanSTARRS DATE: 20/02/21 05:15:46 GMT FROM: Dong Xu at NAOC/CAS D. Xu, X. Liu, Z.P. Zhu, B.Y. Yu, Y. Ma (NAOC), X. Gao (Urumqi No.1 Senior High School) report: We observed the field of the possible X-ray afterglow by Swift/XRT (Burrows et al., GCN 27157) of GRB 200219C detected by Fermi/GBM and Fermi/LAT (GCN 27145; Dirirsa et al., GCN 27151), using the 0.6m NEXT telescope located at Nanshan, Xinjiang, China. Observations started at 22:45:55 UT on 2020-02-20 (i.e., 22.8 h after the Fermi trigger) and 10x300 s Sloan r-band frames were obtained. No optical counterpart is detected in our stacked image at the Swift XRT position, down to a limiting magnitude of r~21.0. Inspection of PanSTARRS reveals a faint, extended source within the XRT error circle. It's localized at coordinates: R.A. (J2000) = 17:30:02.21, Dec.(J2000) = +10:32:22.69, and has r = 22.70 +/- 0.15 mag. Thus is may be the host galaxy of the GRB, if the Swift XRT detection is the afterglow of the GRB. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 27162 SUBJECT: GRB 200219С: Mondy and TSHAO optical observations DATE: 20/02/21 10:54:35 GMT FROM: Alexei Pozanenko at IKI, Moscow I. Reva (FAPHI), A. Pozanenko (IKI), M. Krugov (FAPHI), with Zeiss-1000 1-m telescope of Tien Shan Astronomical Observatory A. Pozanenko (IKI), S. Belkin (IKI), E. Klunko (ISTP), I. Reva (FAPHI), M. Krugov (FAPHI), E. Mazaeva (IKI), A. Volnova (IKI) report on behalf of IKI-GRB-FuN: We observed the field of GRB 200219С (The Fermi GBM team, GCN 27145; Dirirsa et al., GCN 27151; Hamburg et al., GCN 27155) with AZT-33IK 1.5-m telescope of Sayan observatory (Mondy) starting on Feb. 20 (UT) 21:21:45 and with Zeiss-1000 1-m telescope of Tien Shan Astronomical Observatory starting on Feb. 20 (UT) 23:17:45. Within enhanced XRT position of XRT afterglow (Burrows et al., GCN 27157) we detected an optical object in coordinates of (J2000) 17:30:02.275 +10:32:22.47 with uncertainities of 0.3 arcsec in both coordinates. Coordinates are consistent with possible host galaxy (Xu et al., GCN 27161) which is presented in Pan-STARRS catalaog. Preliminary photometry of the object is following. Date UT start t-T0 Filter Exp. OT Err UL(3sigma) telesope (mid, days) (s) 2020-02-20 21:21:45 0.90596 R 40*60 21.55 0.15 22.2 AZT-33IK 2020-02-20 23:17:45 0.99207 R 56*60 n/d n/d 21.3 Z-1000 Photometry is based on the USNO-B2.0 nearby stars. USNO-B1.0 R2 1005-0285285 17.74 1005-0285301 19.23 1005-0285213 19.99 The object is somewhat brighter than that presented in Pan-STARRS DR1, and we suggest this object is a candidate for the afterglow of GRB 200115A. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 27163 SUBJECT: GRB 200219C: CALET Gamma-Ray Burst Monitor detection DATE: 20/02/21 15:33:14 GMT FROM: Valentin Pal'shin at AGU S. Sugita, A. Yoshida, T. Sakamoto, V. Pal'shin (AGU), Y. Kawakubo (LSU), 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 GRB 200219C (Fermi GBM detection: Fermi GBM Team, GCN Circ. 27145, Hamburg et al., GCN Circ. 27155; Fermi-LAT detection: Dirirsa et al., GCN Circ. 27151; https://gcn.gsfc.nasa.gov/other/200219C.gcn3) triggered the CALET Gamma-ray Burst Monitor (CGBM) at 23:57:10.630 UTC on 19 February 2020. The burst signal was seen by only the SGM detector. The burst light curve shows a multi-peaked pulse which starts at T+0.1 sec, peaks at T+1.6 sec and ends at T+4.6 sec. The T90 and T50 durations measured by the SGM data are 4.0 +- 0.7 sec and 2.1 +- 0.9 sec (40-1000 keV), respectively. The ground processed light curve is available at http://cgbm.calet.jp/cgbm_trigger/ground/1266191565/ The CALET data used in this analysis are provided by the Waseda CALET Operation Center located at the Waseda University. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 27166 SUBJECT: GRB 200219C: OAJ afterglow confirmation DATE: 20/02/21 20:03:17 GMT FROM: Alexander Kann at IAA-CSIC M. Blazek, D. A. Kann (both HETH/IAA-CSIC), A. de Ugarte Postigo (HETH/IAA-CSIC, DARK/NBI), C. C. Thoene, J. F. Agui Fernandez (both HETH/IAA-CSIC), N. Maicas, and J. L. Lamadrid (both CEFCA) report: We observed the position of the Fermi GBM/LAT GRB 200219C (Fermi GBM team, GCN #27145, Hamburg et al., GCN #27155, Dirirsa et al., GCN #27151) with the Javalambre Observatory OAJ 80cm telescope in g'r'i'z', obtaining 3 x 300 s exposures in g'r' each, and 5 x 180 s exposures in i'z' each. Observations started on 2020-02-21, 03:17:55 UT. No observations were obtained the night before as the LAT position came only after twilight had started. In the stacked r' image (midtime 1.14375 days after the GRB), we clearly detect a source within the enhanced XRT error circle (Burrows et al., GCN #27157) for which we measure r'(AB) = 22.11 ± 0.13 mag against PanSTARRS field stars. We note this implies a decay compared with the afterglow discovery by Reva et al. (GCN #27162) who find R ~ 21.72 ± 0.15 mag (AB) about six hours earlier. It is still brighter than the PanSTARRS host galaxy magnitude given by Xu et al. (GCN #27161) at r' = 22.70 ± 0.15 mag. The relatively bright host galaxy may be indicative of a low-redshift event. As the source is improving in visibility and will be observable for several months to come, a search for associated supernova emission may be worthwhile. Spectroscopy is encouraged. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 27180 SUBJECT: GRB 200219C: Swift-XRT afterglow confirmation DATE: 20/02/24 21:22:36 GMT FROM: Valerio D'Elia at ASDC V. D’Elia (SSDC) reports on behalf of the Swift-XRT team: We provide an update on the XRT light curve evolution of the candidate X-ray afterglow of GRB 200219C (GCN Circ. 27157). The XRT light curve now comprises data up to 260 ks from the Fermi trigger (GCN Circs. 27151 and 27155). There is a firm indication of fading with respect to the first observation, with a decay index of 0.8 (+0.4 -0.3). We thus confirm that this is indeed the afterglow of GRB 200219C. The latest results can be viewed via: https://www.swift.ac.uk/xrt_curves/00020973/ This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 27228 SUBJECT: Konus-Wind observation of GRB 200219C DATE: 20/02/26 19:03:50 GMT FROM: Dmitry Svinkin at Ioffe Institute D. Svinkin, S. Golenetskii, R. Aptekar, D. Frederiks, M. Ulanov, A. Tsvetkova, A. Lysenko, A. Ridnaia, and T. Cline on behalf of the Konus-Wind team, report: The long-duration GRB 200219C (Fermi-GBM detection: The Fermi GBM team, GCN Circ. 27145; Hamburg et al., GCN Circ. 27155; Fermi-LAT detection: Dirirsa et al., GCN Circ. 27151; CALET-GBM detection: Sugita et al., GCN Circ. 27163) triggered Konus-Wind at T0=86229.162 s UT (23:57:09.162). The burst light curve shows a bright peak which starts at ~T0-3.4 s and has a duration of ~9.8 s, followed by a weaker emission seen up to ~T0+23 s. Total burst duration is ~27 s. The emission is seen up to ~4 MeV. The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB200219_T86229 As observed by Konus-Wind, the burst had a fluence of 1.87(-0.11,+0.13)x10^-5 erg/cm2, and a 64-ms peak flux, measured from T0+3.488 s, of 5.40(-1.08,+1.23)x10^-6 erg/cm2/s (both in the 20 keV - 10 MeV energy range). The time-averaged spectrum of the burst (measured from T0 to T0+29.952 s) is best fit in the 20 keV - 2 MeV range by a power law with exponential cutoff model: dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep) with alpha = -1.08(-0.12,+0.12) and Ep = 209(-21,+27) keV (chi2 = 60/61 dof). Fitting by a GRB (Band) model yields the same alpha and Ep, and an upper limit on the high energy photon index: beta < -2.6 (chi2 = 60/60 dof). The spectrum near the maximum count rate (measured from T0+0.256 to T0+5.376 s) is best fit in the 20 keV - 4 MeV range by the GRB (Band) model with the following parameters: the low-energy photon index alpha = -0.83(-0.10,+0.12), the high energy photon index beta = -3.58(-6.42,+0.82), the peak energy Ep = 234(-22,+20) keV (chi2 = 62/75 dof). All the quoted errors are at the 90% confidence level. All the quoted values are preliminary. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 27298 SUBJECT: GRB 200219C: VLA Detection DATE: 20/03/03 03:29:34 GMT FROM: Virginia Cunningham at U of MD V. Cunningham (UMD), S. B. Cenko (NASA GSFC), S. Vogel (UMD) We observed the Fermi GBM/LAT GRB 200219C (The Fermi GBM Team, GCN 27145; Dirirsa et al., GCN 27151; Hamburg et al., GCN 27155) at 6 GHz with the Karl G. Jansky Very Large Array (VLA) on 2020 Feb 25 11:23:02 UTC (5.48 days post GBM trigger). We report a preliminary flux density of ~658 uJy at position: RA (J2000): 17:30:02.295 +/- 0.011 Dec (J2000): +10:32:22.237 +/- 0.011 This is consistent with the position of the potential host galaxy (Xu et al., GCN 27161), optical afterglow (Reva et al., GCN 27162; Blazek et al., GCN 27166), and X-ray afterglow (Burrows et al., GCN 27157). We thank the VLA staff for their assistance in completing these observations.