//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23648 SUBJECT: GRB 190109B: Swift detection of a burst DATE: 19/01/09 12:18:35 GMT FROM: Scott Barthelmy at NASA/GSFC B. Sbarufatti (PSU), S. D. Barthelmy (GSFC), J.D. Gropp (PSU), J. A. Kennea (PSU) and K. L. Page (U Leicester) report on behalf of the Neil Gehrels Swift Observatory Team: At 11:56:09 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 190109B (trigger=882809). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 55.595, +63.578, which is RA(J2000) = 03h 42m 23s Dec(J2000) = +63d 34' 40" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve shows a single peak with a duration of about 10 sec. The peak count rate was ~1700 counts/sec (15-350 keV), at ~0 sec after the trigger. The XRT began observing the field at 11:57:36.3 UT, 87.1 seconds after the BAT trigger. No source was detected in the 2.5-s promptly available image. We are waiting for the full dataset to detect and localise the XRT counterpart. UVOT took a finding chart exposure of 150 seconds with the White filter starting 90 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 25% of the BAT 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 BAT error circle. The list of sources is typically complete to about 18 mag. No correction has been made for the expected extinction corresponding to E(B-V) of 0.70. Even without an XRT detection, we believe this event to be a real GRB given an 8.6 sigma detection in BAT and that there is a temporal coincidence with a Fermi-GBM event. However there still is a possibility that this is not real. We will have to wait for the full data set to be downlinked. Burst Advocate for this burst is B. Sbarufatti (bxs60 AT psu.edu). 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: 23651 SUBJECT: GRB 190109B: Swift-XRT observations DATE: 19/01/09 13:21:11 GMT FROM: Phil Evans at U of Leicester D.N. Burrows (PSU), J.A. Kennea (PSU), S. Campana (INAF-OAB), G. Cusumano (INAF-IASF PA), P.A. Evans (U. Leicester) and J.P. Osborne (U. Leicester) report on behalf of the Swift-XRT team: The XRT began observing the field of GRB 190109B at 11:57:36.3 UT, 87.1 seconds after the BAT trigger. Using promptly downlinked data we find a fading, uncatalogued X-ray source with an enhanced position: RA, Dec 55.4870, 63.5920 which is equivalent to: RA(J2000) = 03h 41m 56.88s Dec(J2000) = +63d 35' 31.2" with an uncertainty of 2.1 arcseconds (radius, 90% containment). This location is 180 arcseconds from the BAT onboard position, outside 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. A power-law fit to a spectrum formed from promptly downlinked event data gives a column density consistent with the Galactic value of 4.56 x 10^21 cm^-2 (Willingale et al. 2013). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23652 SUBJECT: GRB 190109B: Enhanced Swift-XRT position DATE: 19/01/09 14:22:21 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 649 s of XRT Photon Counting mode data and 1 UVOT images for GRB 190109B, 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 = 55.48723, +63.59203 which is equivalent to: RA (J2000): 03h 41m 56.94s Dec (J2000): +63d 35' 31.3" with an uncertainty of 1.8 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: 23654 SUBJECT: GRB 190109B: Mondy optical upper limit DATE: 19/01/09 15:29:40 GMT FROM: Alexei Pozanenko at IKI, Moscow S. Belkin (IKI), E. Klunko (ISTP), A. Pozanenko (IKI), E. Mazaeva (IKI), A. Volnova (IKI) report on behalf of IKI-FuN: We observed the field of the GRB 190109B (Sbarufatti et al., GCN 23648) with AZT-33IK telescope of Sayan observatory (Mondy). We obtained several images in R-filter starting on Jan. 09 (UT) 12:17:03, i.e. 21 minutes after the burst trigger. We do not detect any object within enhanced Swift-XRT position (Beardmore et al., GCN 23652). Preliminary photometry of the field is following. Date UT start t-T0 Filter Exp. OT Err. UL(3sigma) (mid, days) (s) 2019-01-09 12:17:03 0.02463 R 1900 n/d n/d 22.6 The photometry is based on several nearby USNO-B1.0 stars. [GCN OPS NOTE(09jan19): Using information from Circ# 23657, the SUBJECT-line and first sentence has been changed from 190109A to 190109B.] //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23655 SUBJECT: GRB 190109B: BOOTES-5/JGT optical observations DATE: 19/01/09 15:44:19 GMT FROM: Alberto Castro-Tirado at Inst.de Astro. de Andalucia X.-Y.Li, Y.-D. Hu, I. Carrasco, E. Fernandez-Garcia and A. J. Castro-Tirado (IAA-CSIC), D. Hiriart and W. H. Lee (UNAM), S. Jeong and I. H. Park (SKKU) and M. D. Caballero-Garcia (ASU-CAS, CZ) on behalf of a larger collaboration, report: The 60cm BOOTES-5/JGT robotic telescope at Observatorio Astronomico Nacional in San Pedro Martir (Mexico) followed-up GRB 190109B (Sbarufatti et al., GCNC 23648) starting at 13:30 UT (~1.6 hr after trigger). Within the enhanced Swift/XRT position (Beardmore et al., GCNC 23652), no optical afterglow is found down to 20.4 mag in the r-band on the co-added image, in agreement with the UVOT upper limit (Sbarufatti et al., GCNC 23648). We thank the staff at Observatorio Astronomico Nacional in San Pedro Martir for its excellent support. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23656 SUBJECT: GRB 190109B: COATLI Optical Observations DATE: 19/01/09 16:11:22 GMT FROM: Alan M. Watson at Instituto de Astronomia UNAM Eleonora Troja (GSFC), Alan M. Watson (UNAM), Nat Butler (ASU), Rosa L. Becerra (UNAM), William H. Lee (UNAM), Margarita Pereyra (UNAM), Carlos Román-Zúñiga (UNAM), and Alexander Kutyrev (GSFC) report: We observed the field of GRB 190109B (Sbarufatti et al., GCN Circ. 23642) 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 2019-01-09 11:57:47.6 to 13:27:45.2 (from 98.5 seconds to 1.53 hours after the trigger) at air masses above 3, obtaining a total of 59.1 minutes of exposure in the w filter. We do not detect an optical source within the enhanced XRT position region (Beardmore et al., GCN Circ. 23652) to a 5-sigma limiting magnitude of w = 20.3. 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 thank the COATLI technical team and the staff of the Observatorio Astronómico Nacional. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23657 SUBJECT: Correction to the GCN circ. 23654 / GRB 190109B: Mondy optical upper limit DATE: 19/01/09 16:43:11 GMT FROM: Alexei Pozanenko at IKI, Moscow A. Pozanenko (IKI) report on behalf of IKI-FuN: The title and text of the GCN circ. 23654 refers to the GRB 190109B, not GRB 190109A. We apologize for possible inconvenience. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23659 SUBJECT: GRB 190109B: Swift-BAT refined analysis DATE: 19/01/09 17:11:22 GMT FROM: Scott Barthelmy at NASA/GSFC M. Stamatikos (OSU), S. D. Barthelmy (GSFC), J. R. Cummings (CPI), H. A. Krimm (NSF/USRA), A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU), B. Sbarufatti (PSU), T. N. Ukwatta (LANL) (i.e. the Swift-BAT team): Using the data set from T-60 to T+243 sec from recent telemetry downlinks, we report further analysis of BAT GRB 190109B (trigger #882809) (Sbarufatti, et al., GCN Circ. 23648). The BAT ground-calculated position is RA, Dec = 55.563, 63.592 deg, which is RA(J2000) = 03h 42m 15.1s Dec(J2000) = +63d 35' 31.7" with an uncertainty of 1.4 arcmin, (radius, sys+stat, 90% containment). The partial coding was 60%. The mask-weighted light curve shows a couple overlapping peaks starting at ~T-4sec, peaking at ~T+1 sec, and a shallow tail out to ~T+40 sec. T90 (15-350 keV) is 5.92 +- 0.78 sec (estimated error including systematics). The time-averaged spectrum from T-4.24 to T+3.31 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.58 +- 0.16. The fluence in the 15-150 keV band is 4.8 +- 0.5 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T-0.12 sec in the 15-150 keV band is 1.7 +- 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/882809/BA/ //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23662 SUBJECT: GRB 190109B: Swift-XRT refined Analysis DATE: 19/01/09 19:58:19 GMT FROM: Phil Evans at U of Leicester P.A. Evans (U. Leicester), A. Melandri (INAF-OAB), P. D'Avanzo (INAF-OAB), V. D'Elia (ASDC), S. J. LaPorte (PSU), J.A. Kennea (PSU), J.P. Osborne (U. Leicester), K.L. Page (U. Leicester) and B. Sbarufatti report on behalf of the Swift-XRT team: We have analysed 6.5 ks of XRT data for GRB 190109B (Sbarufatti et al. GCN Circ. 23648), from 96 s to 18.3 ks after the BAT trigger. The data are entirely in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Beardmore et al. (GCN Circ. 23652). The light curve can be modelled with a power-law decay with a decay index of alpha=0.97 (+/-0.06). A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 2.04 (+0.27, -0.21). The best-fitting absorption column is 5.1 (+1.6, -0.5) x 10^21 cm^-2, consistent with the Galactic value of 4.6 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 4.0 x 10^-11 (6.7 x 10^-11) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Total column: 5.1 (+1.6, -0.5) x 10^21 cm^-2 Galactic foreground: 4.6 x 10^21 cm^-2 Excess significance: <1.6 sigma Photon index: 2.04 (+0.27, -0.21) If the light curve continues to decay with a power-law decay index of 0.97, the count rate at T+24 hours will be 2.2 x 10^-3 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 8.7 x 10^-14 (1.5 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/00882809. This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23664 SUBJECT: GRB 190109B: Swift/UVOT Upper Limits DATE: 19/01/09 20:37:32 GMT FROM: Kira Simpson at PSU GRB 190109B: Swift/UVOT Upper Limits K. K. Simpson (PSU) and B. Sbarufatti (PSU) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 190109B 91 s after the BAT trigger (Sbarufatti et al., GCN Circ. 23648). No optical afterglow consistent with the XRT position (Beardmore et al. GCN Circ. 23652) 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 91 241 147 >20.7 u_FC 303 553 246 >20.7 white 91 6461 727 >22.1 v 634 6860 441 >20.4 b 559 6256 432 >20.9 u 303 6050 470 >21.0 w1 683 5845 236 >20.2 m2 5440 5640 197 >20.8 w2 5030 6666 393 >20.2 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.72 in the direction of the burst (Schlegel et al. 1998). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23666 SUBJECT: GRB 190109B: Fermi GBM observation DATE: 19/01/09 23:30:49 GMT FROM: Cori Fletcher at USRA/NASA C. Fletcher (USRA) and C. Meegan (UAH) report on behalf of the Fermi GBM Team: "At 11:56:10.76 UT on 09 January 2019, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 190109B (trigger 568727775 / 190109497) which was also detected by the Swift (Sbarufatti et al. 2019, GCN 23648). The GBM on-ground location is consistent with the Swift position. The angle from the Fermi LAT boresight at the GBM trigger time is 46 degrees. The GBM light curve consists of a single peak with a duration (T90) of about 8 s (50-300 keV). The time-averaged spectrum from T0-6.1 s to T0+3.1 s is best fit by a power law function with an exponential high-energy cutoff. The power law index is -0.85 +/- 0.25 and the cutoff energy, parameterized as Epeak, is 92 +/- 14 keV. The event fluence (10-1000 keV) in this time interval is (6.76 +/- 0.67)E-7 erg/cm^2. The 1-sec peak photon flux measured starting from T0-1.6 s in the 10-1000 keV band is 2.8 +/- 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: 23711 SUBJECT: GRB190109B: MITSuME Akeno optical upper limits DATE: 19/01/15 11:15:43 GMT FROM: Motoki Oeda at Tokyo Inst. of Tech. M. Oeda, K. L. Murata, R. Itoh, Y. Tachibana, S. Harita, K. Morita, K.Shiraishi, K. Iida, M. Niwano, R. Adachi, Y. Yatsu, and N. Kawai (TokyoTech) report on behalf of the MITSuME collaboration: We searched for the optical counterpart of GRB 190109B (B. Sbarufatti et al.,GCN Circular #23648) with the optical three color (g', Rc, and Ic) CCD cameras attached to the MITSuME 50 cm telescope of Akeno Observatory,Yamanashi, Japan. The observation started on 11:57:03.81 UT. We did not find any new point source within the enhanced XRT circle (A.P. Beardmore et al., GCN Circular #23652) in all three bands. We obtained following 5 sigma limits for the magnitudes. T0+[min] MID-UT T-EXP[sec] g' Rc Ic ------------------------------------------------------------------------------------------------------- 0.913 11:57:33.81 60 >17.54 >17.26 >16.72 0.913 12:31:59.3 3660 >19.29 >17.67 >17.12 ------------------------------------------------------------------------------------------------------- T0+ : Elapsed time after the burst T-EXP: Total Exposure time We used UCAC-4 catalog for flux calibration.