//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23830 SUBJECT: GRB 190202A: Swift detection of a burst with an optical counterpart DATE: 19/02/02 01:58:11 GMT FROM: Aaron Tohuvavohu at PSU/Swift A. Y. Lien (GSFC/UMBC), P. D'Avanzo (INAF-OAB), J.D. Gropp (PSU), N. J. Klingler (PSU), N. P. M. Kuin (UCL-MSSL), F. E. Marshall (NASA/GSFC), D. M. Palmer (LANL), M. H. Siegel (PSU) and A. Tohuvavohu (PSU) report on behalf of the Neil Gehrels Swift Observatory Team: At 01:39:30 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 190202A (trigger=887217). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 166.512, +9.388 which is RA(J2000) = 11h 06m 03s Dec(J2000) = +09d 23' 17" 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 30 sec. The peak count rate was ~4500 counts/sec (15-350 keV), at ~5 sec after the trigger. The XRT began observing the field at 01:42:13.5 UT, 163.2 seconds after the BAT trigger. XRT found a bright, uncatalogued X-ray source located at RA, Dec 166.5026, 9.3779 which is equivalent to: RA(J2000) = 11h 06m 0.62s Dec(J2000) = +09d 22' 40.4" with an uncertainty of 5.9 arcseconds (radius, 90% containment). This location is 49 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. UVOT took a finding chart exposure of 126 seconds with the White filter starting 172 seconds after the BAT trigger. There is a candidate afterglow in the rapidly available 2.7'x2.7' sub-image at RA(J2000) = 11:06:00.63 = 166.50262 DEC(J2000) = +09:22:36.6 = 9.37683 with a 90%-confidence error radius of about 0.74 arc sec. This position is 3.9 arc sec. from the center of the XRT error circle. The estimated magnitude is 16.01 with a 1-sigma error of about 0.14. No correction has been made for the expected extinction corresponding to E(B-V) of 0.02. Burst Advocate for this burst is A. Y. Lien (amy.y.lien AT nasa.gov). 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: /too.html.) //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23831 SUBJECT: GRB 190202A: Koshka Zeiss-1000 optical observations DATE: 19/02/02 03:29:43 GMT FROM: Alexei Pozanenko at IKI, Moscow A. Novichonok (KIAM), A. Pozanenko (IKI), E. Mazaeva (IKI), S. Belkin (IKI), A. Volnova (IKI), I. Molotov (KIAM) report on behalf of larger GRB follow-up collaboration: We observed the field of GRB 190202A (Lien , et al., GCN 23830) with Zeiss-1000 1-m telescope of Koshka Observatory starting on Feb. 02 (UT) 02:40:34 in R-filter. We detect the optical afterglow (Lien , et al., GCN 23830) in coordinates (J2000) 11:06:00.60 +09:22:36.2 (uncertainiies in both coordinates of 0.5 arcsec) coinciding with reported in GCN 23830. Preliminary photometry of the afterglow at 2019-02-02 02:49:35 is R=17.8 +/- 0.15. The photometry is based on several nearby USNO-B1.0 stars. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23832 SUBJECT: GRB 190202A: Enhanced Swift-XRT position DATE: 19/02/02 09:28:31 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 348 s of XRT Photon Counting mode data and 1 UVOT images for GRB 190202A, 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 = 166.50234, +9.37689 which is equivalent to: RA (J2000): 11h 06m 0.56s Dec (J2000): +09d 22' 36.8" with an uncertainty of 1.7 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: 23833 SUBJECT: GRB 190202A: GOTO optical observations DATE: 19/02/02 12:48:07 GMT FROM: Danny Steeghs at U.of Warwick/GOTO D.Steeghs (U.Warwick), Y.-L.Mong (Monash U.), G.Ramsay (Armagh O.), M.Dyer (U. Sheffield), J.Lyman, K.Ulaczyk (U. Warwick), 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.Poshyachindav(NARIT), D.Pollacco (U. Warwick), E.Thrane (Monash U.), E.Palle (IAC) report on behalf of the GOTO collaboration: In response to Swift BAT trigger 887217 (GRB190202A; Lien et al. GCN 23830), the Gravitational-wave Optical Transient Observer (GOTO) observed the survey field covering the Swift BAT/XRT positions. Due to adverse weather, observations started at 2019-02-02T03:51:41 (2.2 hours post burst) consisting of a set of 5x120s exposures in our wide L filter (400-700nm). We detect the optical counterpart coincident with the revised XRT position reported in Evans et al. (GCN 23832) at a S/N of 18. Preliminary pipeline photometry based off a PS1 zeropoint provides g=19.1 +/- 0.2, with the uncertainty including a systematic error component due to the calibration uncertainty. This has not been corrected for galactic extinction. 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: 23834 SUBJECT: GRB 190202A: Swift/UVOT Detection DATE: 19/02/02 13:00:54 GMT FROM: Paul Kuin at MSSL Paul Kuin (UCL/MSSL) and A. Y. Lien (GSFC/UMBC) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 190202A 173 s after the BAT trigger (Lien et al., GCN Circ. 23830). The source was also observed in R (Novichonok et al., GCN Circ. 23831). A source consistent with the XRT position (Evans et al. GCN Circ. 23832) is detected in the initial UVOT exposures. The preliminary UVOT position is: RA (J2000) = 11:06:00.63 = 166.50261 (deg.) Dec (J2000) = +09:22:36.7 = 9.37687 (deg.) with an estimated uncertainty of 0.42 arc sec. (radius, 90% confidence). Preliminary detections and 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early exposures are: Filter T_start(s) T_stop(s) Exp(s) Mag white 173 299 124 16.02 +/- 0.03 v 1613 2153 78 17.94 +/- 0.18 b 1711 1903 39 18.38 +/- 0.16 u 1686 2054 58 18.20 +/- 0.17 w1 1662 2376 97 >18.5 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.02 in the direction of the burst (Schlegel et al. 1998). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23835 SUBJECT: GRB 190202A: AGILE ratemeters detection DATE: 19/02/02 13:29:32 GMT FROM: Francesco Verrecchia at ASDC F. Verrecchia (SSDC, and INAF/OAR), A. Ursi (INAF/IAPS), M. Tavani (INAF/IAPS, and Univ. Roma Tor Vergata), M. Cardillo, Y. Evangelista, G. Piano (INAF/IAPS), C. Pittori, F. Lucarelli, (SSDC, and INAF/OAR), F. Longo (Univ. Trieste and INFN Trieste), A. Bulgarelli, V. Fioretti, F. Fuschino (INAF/OAS-Bologna), A. Argan (INAF/IAPS), A. Giuliani (INAF/IASF-Mi), M. Marisaldi (INAF/OAS, and Bergen University), M. Pilia, A. Trois (INAF/OA-Cagliari), I. Donnarumma (ASI), report on behalf of the AGILE Team: AGILE detected the long GRB 190202A first reported by Swift in Lien et al., GCN 23830, in the scientific ratemeters of the Anti-Coincidence (50-200 keV), Super-AGILE (SA; 18-60 keV) and Mini-Caloremeter (MCAL; 0.4-100 MeV) detectors. The event position was not exposed by the AGILE Gamma-Ray Imaging Detector. The low significance event lasted about 15s in the three light curves with the SA one starting about 8 s before the trigger time and the MCAL one about 10 s before. Further analyses are still in progress. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23836 SUBJECT: GRB 190202A, Swift-BAT refined analysis DATE: 19/02/02 19:42:08 GMT FROM: Amy Lien at GSFC C. B. Markwardt (GSFC), S. D. Barthelmy (GSFC), J. R. Cummings (CPI), H. A. Krimm (NSF/USRA), A. Y. Lien (GSFC/UMBC), 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-240 to T+400 sec from the recent telemetry downlink, we report further analysis of BAT GRB 190202A (trigger #887217) (Lien et al., GCN Circ. 23830). The BAT ground-calculated position is RA, Dec = 166.506, 9.393 deg which is RA(J2000) = 11h 06m 01.4s Dec(J2000) = +09d 23' 33.9" with an uncertainty of 1.9 arcmin, (radius, sys+stat, 90% containment). The partial coding was 4%. The mask-weighted light curve shows two overlapping pulses that start at ~T0 and end at ~T+25 s. The two peaks occur at ~T0 and ~T+5 s, respectively, Note that the burst location came into the BAT field of view at ~T-69 s, and Swift went into SAA at ~T+210 s. T90 (15-350 keV) is 19.4 +- 6.9 sec (estimated error including systematics). The time-averaged spectrum from T-0.90 to T+26.52 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.32 +- 0.13. The fluence in the 15-150 keV band is 6.0 +- 0.5 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+4.68 sec in the 15-150 keV band is 7.8 +- 1.5 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/887217/BA/ //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23838 SUBJECT: GRB 190202A: Fermi GBM observation DATE: 19/02/02 21:12:16 GMT FROM: Peter Veres at UAH P. Veres and C. Meegan (both UAH) report on behalf of the Fermi GBM Team: "At 01:39:26.21 UT on 02 February 2019, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 190202A (trigger 570764371 / 190202069) which was also detected by the Swift/BAT (Lien et al., GCN 23830). The GBM on-ground location is consistent with the Swift position. The angle from the Fermi LAT boresight at the GBM trigger time is 76 degrees. The GBM light curve shows a dominant pulse with some structure with a duration (T90) of about 18.4 s (50-300 keV). The time-averaged spectrum from T0-0.4 s to T0+12.8 s is best fit by a Band function with Epeak = 287 +/- 18 keV, alpha = -0.74 +/- 0.04, and beta = -2.22 +/- 0.12. The event fluence (10-1000 keV) in this time interval is (1.81 +/- 0.03)E-5 erg/cm^2. The 1-sec peak photon flux measured starting from T0+5.4 s in the 10-1000 keV band is 13.6 +/- 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: 23839 SUBJECT: GRB 190202A: LCO-CTIO optical observations DATE: 19/02/02 21:34:03 GMT FROM: Antonino Cucchiara at UVI A. Cucchiara (U. of the Virgin Islands) reports on behalf of a larger collaboration: We observed Swift GRB 190202A (Tohuvavohu et al. GCN 23803) with the LCO 1-m units at CTIO on January 2, from 06:49 to 07:40 UT (corresponding to 0.2 to 0.25 hours from the GRB trigger time) with the SDSS r' and i' filters. We performed a series of 10x120s in both filters and we clearly detect the optical afterglow (Novichonok et al. GCN 23831) with the following magnitudes: r' = 19.57 +- 0.04 i' = 19.19 +- 0.05 These magnitude are calibrated against several SDSS objects near the GRB location and are not corrected for Galactic Extinction. These observations were possible thanks to the USVI NASA-EPSCoR Research Infrastructure Development (RID) grant NNX16AL44A. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23840 SUBJECT: GRB 190202A: Swift-XRT refined Analysis DATE: 19/02/02 23:24:29 GMT FROM: Paolo D'Avanzo at INAF-OAB A. Y. Lien (GSFC/UMBC) reports on behalf of the Swift-XRT team: We have analysed 3.6 ks of XRT data for GRB 190202A (Lien et al. GCN Circ. 23830), from 152 s to 65.6 ks after the BAT trigger. The data comprise 819 s in Windowed Timing (WT) mode (the first 9 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. 23832). The light curve can be modelled with an initial power-law decay with an index of alpha=0.592 (+0.021, -0.077), followed by a break at T+1879 s to an alpha of 1.47 (+0.05, -0.04). A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 1.89 (+/-0.05). The best-fitting absorption column is consistent with the Galactic value of 2.4 x 10^20 cm^-2 (Willingale et al. 2013). The PC mode spectrum has a photon index of 1.82 (+0.13, -0.12) and a best-fitting absorption column of 6.8 (+3.2, -2.9) x 10^20 cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.6 x 10^-11 (4.1 x 10^-11) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Total column: 6.8 (+3.2, -2.9) x 10^20 cm^-2 Galactic foreground: 2.4 x 10^20 cm^-2 Excess significance: 2.5 sigma Photon index: 1.82 (+0.13, -0.12) If the light curve continues to decay with a power-law decay index of 1.47, the count rate at T+24 hours will be 0.027 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 9.8 x 10^-13 (1.1 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/00887217. This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23841 SUBJECT: GRB 190202A: McDonald 0.8-m telescope optical observation DATE: 19/02/03 05:22:41 GMT FROM: Gregory SungHak Paek at SNU Gregory S. H. Paek, Myungshin Im, Lim Gu, on behalf of a larger collaboration We observed the afterglow of GRB 190202A (Lien et al., GCN 23830; Novichonok et al., GCN 23831; Evans et al., GCN 23832; Steeghs et al., GCN 23833; Kuin et al., GCN 23834; Verrecchia et al., GCN 23835; Markwardt et al., GCN 23836; Veres et al., GCN 23838; Cucchiara et al., GCN 23839; Lien et al., GCN 23840) with the 0.8-m telescope at the McDonald observatory. The observation started at 2019-02-02 08:02 UT or about 6.3 hours after the initial alert. The afterglow is detected in R bands, and preliminary magnitudes are derived, using nearby Pan-STARRS stars as photometry references. Filter Date UT-start exptime[sec] AB_mag R 2019-02-02 08:02:05 180*3 19.72 +/- 0.15 //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23842 SUBJECT: GRB 190202A: NOT optical observations DATE: 19/02/03 08:45:29 GMT FROM: Daniele Malesani at Dark Cosmology Centre, Niels Bohr Inst D. Malesani (DAWN/NBI and DARK/NBI), A. de Ugarte Postigo (HETH/IAA-CSIC, DARK/NBI), and H. J. Deeg (IAC) report on behalf of a larger collaboration: We observed the optical afterglow of GRB 190202A (Lien et al., GCN 23830) using the Nordic Optical Telescope (NOT) equipped with the StanCam imager. Observations were carried out starting on 2019 Feb 3.06 UT (0.99 days after the GRB). A total of 3x600 s in the SDSS g band was acquired. Calibrating against nearby reference stars from the SDSS catalog, we measure for the afterglow a preliminary magnitude of g = 21.72 +- 0.03 (AB). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23843 SUBJECT: GRB 190202A: TSHAO optical observations DATE: 19/02/03 11:14:49 GMT FROM: Alexei Pozanenko at IKI, Moscow S. Belkin (IKI), I. Reva (FAPHI), A. Pozanenko (IKI), E. Mazaeva (IKI), A. Volnova (IKI), A. Kusakin (FAPHI), M. Krugov (FAPHI) report on behalf of IKI-GRB-FuN collaboration: We observed the afterglow of GRB 190202A (Lien et al., GCN 23830; Novichonok et al., GCN 23831; Evans et al., GCN 23832; Steeghs et al., GCN 23833; Kuin et al., GCN 23834; Verrecchia et al., GCN 23835; Markwardt et al., GCN 23836; Veres et al., GCN 23838; Cucchiara et al., GCN 23839; Lien et al., GCN 23840; Paek et al., GCN 23841; Malesani et al., GCN 23842) with Zeiss-1000 1-m telescope of Tien Shan Astronomical Observatory starting on Feb. 02 (UT) 21:04:32. Preliminary photometry of the field is following. Date UT start t-T0 Filter Exp. OT Err. UL (mid, days) (s) 2019-02-02 21:04:32 0.82502 R 21*120 20.43 0.11 21.6 The photometry is based on nearby USNO-B1.0 stars //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23844 SUBJECT: GRB 190202A: SAO RAS optical observations DATE: 19/02/03 14:23:55 GMT FROM: Moskvitin Alexander at SAO RAS A. S. Moskvitin and O. I. Spiridonova (SAO RAS) report on behalf of larger collaboration. We observed the field of the GRB 190202A (Lien et al., GCNC #23830) with the Zeiss-1000 telescope of SAO RAS (+ CCD photometer) on February, 3, 2:21:17--3:13:27 UT (mid.date 2:47:22). The observations were carried out in Rc band. We detected the OT (Novichonok et al., GCNC #23831; Steeghs et al., GCNC #23833; Paul Kuin & A. Y. Lien, GCNC #23834; Cucchiara, GCNC #23839; Paek et al., GCNC #23841; Malesani et al., GCNC #23842; Belkin et al., 23843) in the stacked 9 x 300 sec image. Preliminary brightness of OT is R = 21.45 +/- 0.15 (T-T0 = 1.047 d). The calibrations is based on nearby SDSS stars, magnitudes converted with the Lupton 2005 equations. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23853 SUBJECT: GRB 190202A: R and I band observation from HCT DATE: 19/02/04 07:09:08 GMT FROM: Brajesh Kumar at Indian Inst. of Astrophysics Brajesh Kumar (IIA), Avinash Singh (IIA), Ashish Raj (IIA), S. B. Pandey (ARIES), D. K. Sahu (IIA) and G. C. Anupama (IIA) We observed the field of GRB 190202A (Lien et al., GCNC 23830) with the 2-m Himalayan Chandra Telescope (HCT) located at the Indian Astronomical Observatory, Hanle, India on 2019-02-02 (21:32:29 UT). Two frames in Bessell R and I-bands with an exposure time of 300 sec each were obtained. The OT candidate (Novichonok et al., GCNC 23831; Steeghs et al., GCNC 23833; Cucchiara, GCNC 23839; Paek et al., GCNC 23841; Malesani et al., GCNC 23842; Belkin et al., 23843; Moskvitin & Spiridonova, GCNC 23844) is clearly detected in both frames at the Swift UVOT coordinates (Kuin & Lien, GCNC 23834). The preliminary magnitudes calibrated against the USNO-B1.0 catalogue are following: UT-mid Band Mag ------------------- ------ -------------- 2019-02-02 21:34:59 R 20.66 +/- 0.17 2019-02-02 21:40:56 I 20.08 +/- 0.20 We thank the observing staff at IAO and CREST for helping with the observations. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23870 SUBJECT: GRB 190202A: SAO RAS further optical observations DATE: 19/02/04 19:53:15 GMT FROM: Moskvitin Alexander at SAO RAS A. S. Moskvitin, O. I. Spiridonova, O. A. Maslennikova (SAO RAS), and A. A. Volnova (IKI RAS) report on behalf of larger collaboration. We observed the field of the GRB 190202A (Lien et al., GCNC #23830) with the Zeiss-1000 telescope of SAO RAS (+ CCD photometer) on February, 3, 21:15:42--22:45:25 UT (mid. time 22:00:33). The observations were carried out in Rc band. We detected the OT (Novichonok et al., GCNC #23831; Steeghs et al., GCNC #23833; Paul Kuin & A. Y. Lien, GCNC #23834; Cucchiara, GCNC #23839; Paek et al., GCNC #23841; Malesani et al., GCNC #23842; Belkin et al., 23843; Moskvitin & Spiridonova, GCNC #23844; Brajesh Kumar et al., GCNC #23853) in the stacked 15 x 300 sec image. Preliminary brightness of OT is R = 21.9 +/- 0.1 (T-T0 = 1.848 d). The calibrations is based on nearby SDSS stars, magnitudes converted with the Lupton 2005 equations. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23871 SUBJECT: GRB 190202A: Xinglong-2.16m optical observations DATE: 19/02/05 01:35:49 GMT FROM: Dong Xu at NAOC/CAS D. Xu, Z.P. Zhu, B.J. Xi, B.Y. Yu, F. Xiao, H.J. Wang (NAOC), J.H. Liu, X. Zhang (XAO) report on behalf of a larger collaboration: We observed the field of GRB 190202A (Lien et al., GCN 23830) using the Xinglong-2.16m equipped with the BFOSC camera. Observations were carried out starting at 17:26:32 UT on 2019-02-03, and 6x600s R-band frames were obtained. The previously reported afterglow (e.g., Lien et al., GCN 23830; Novichonok et al., GCN 23833, Cucchiara, GCN 23839; Paek et al., GCN 23841; Malesani et al., GCN 23842; Belkin et al., 23843; Moskvitin & Spiridonova, GCN 23844; Kumar et al., GCN 23853; Moskvitin et al., GCN 23870) is very weakly detected in our stacked image, with R=22.0 +/- 0.4 mag (at Tmid-T0 = 1.679 days post-burst), calibrated with nearby SDSS stars. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23874 SUBJECT: GRB190202A: GROWTH-India detection of optical afterglow DATE: 19/02/05 04:35:21 GMT FROM: Varun Bhalerao at Indian Inst of Tech Harsh Kumar (IITB), Shubham Srivastav (IITB), Viraj karambelkar (IITB), Gaurav Waratkar(IITB), Tsewang Stanzin (IAO, IIA), Varun Bhalerao (IITB), G.C. Anupama (IIA) report on behalf of the GROWTH-India collaboration: We observed the optical afterglow of GRB190202A (Lien , et al., GCN 23830, Novichonok et al. GCN 23831, Kuin P, et al. GCN 23834, Cucchiara A, et al. GCN 23839) with the 0.7m robotic GROWTH-India telescope at the Indian Astronomical Observatory.Observation were started at 2019-02-02 19:25:26.704. We observed the field using r filter with 600sec exposure.. We clearly detected a faint afterglow source at coordinates specified in (Kuin P, et al. GCN 23834). Magnitudes were calibrated using PanSTARRs reference stars in the same field from the PS1 catalog. The measured magnitude in r filter image is 20.58 +/- 0.1 (AB magnitude) GROWTH India telescope is a 70-cm telescope with a 0.7 degree field of view, set up by the Indian Institute of Astrophysics and the Indian Institute of Technology Bombay with support from the Indo-US Science and Technology Forum (IUSSTF) and the Science and Engineering Research Board (SERB) of the Department of Science and Technology (DST), Government of India (https://sites.google.com/view/growthindia/). It is located at the Indian Astronomical Observatory (Hanle), operated by the Indian Institute of Astrophysics (IIA). [GCN OPS NOTE(05feb19): The Operator has added the "A" to the GRB name in the SUBJECT-line and in the body of the circular.] //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23875 SUBJECT: GRB 190202A: AstroSat CZTI detection DATE: 19/02/05 06:45:51 GMT FROM: Vidushi Sharma at IUCAA V. Sharma, T. Khanam 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 long GRB 190202A, which was also detected by Swift (Lien A. Y. et al., GCN Circ 23830), AGILE ratemeters (Verrecchia F. et al., GCN Circ 23835) and Fermi GBM (Veres P. et al., GCN Circ 23838). The source was clearly detected in the 20-200 keV energy range. The light curve shows multiple peaks of emission with the strongest peak at 01:39:31.5 UT. The measured peak count rate is 453 cts/s above the background in the combined data of four quadrants, with a total of 3173 cts. The local mean background count rate was 471 cts/s. Using cumulative rates, we measure a T90 of 14.8 s. 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: 23881 SUBJECT: GRB 190202A: Terskol 2-m optical observations DATE: 19/02/07 21:13:59 GMT FROM: Moskvitin Alexander at SAO RAS I. V. Sokolov (Terskol Peak Observatory), A. V. Sergeev (Terskol Peak Observatory), A. S. Moskvitin (SAO RAS), V. B. Petkov (BNO INR RAS) report on behalf of larger collaboration. We observed the field of the GRB 190202A (Lien et al., GCNC #23830) with the Zeiss-2000 telescope of Terskol Peak Observatory on February, 3, 21:14:49--22:52:52 UT. We detected the OT (Novichonok et al., GCNC #23831; Steeghs et al., GCNC #23833; Paul Kuin & A. Y. Lien, GCNC #23834; Cucchiara, GCNC #23839; Paek et al., GCNC #23841; Malesani et al., GCNC #23842; Belkin et al., 23843; Moskvitin & Spiridonova, GCNC #23844; Brajesh Kumar et al., GCNC #23853; Moskvitin et al., GCNC #23870; Xu et al., GCNC #23871) in the stacked 16 x 180 sec. R band image. Preliminary brightness of OT is R = 21.92 +/- 0.17 (T-T0 = 1.850 d). The calibrations is based on nearby SDSS stars, magnitudes converted with the Lupton 2005 equations.