//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23642 SUBJECT: GRB 190109A: Swift detection of a burst DATE: 19/01/09 05:25:13 GMT FROM: Scott Barthelmy at NASA/GSFC J.D. Gropp (PSU), S. D. Barthelmy (GSFC), M. J. Moss (George Washington University), D. M. Palmer (LANL) and A. Tohuvavohu (PSU) report on behalf of the Neil Gehrels Swift Observatory Team: At 05:12:41 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 190109A (trigger=882747). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 33.218, +38.110, which is RA(J2000) = 02h 12m 52s Dec(J2000) = +38d 06' 36" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve shows several peaks with a total duration of about 70 sec. The peak count rate was ~700 counts/sec (15-350 keV), at ~8 sec after the trigger. The XRT began observing the field at 05:15:30.6 UT, 168.9 seconds after the BAT trigger. Using promptly downlinked data we find a bright, fading, uncatalogued X-ray source located at RA, Dec 33.20430, 38.10690 which is equivalent to: RA(J2000) = 02h 12m 49.03s Dec(J2000) = +38d 06' 24.8" with an uncertainty of 3.9 arcseconds (radius, 90% containment). This location is 40 arcseconds from the BAT onboard position, within 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. No spectrum from the promptly downlinked event data is yet available to determine the column density. The initial flux in the 2.5 s image was 2.06e-09 erg cm^-2 s^-1 (0.2-10 keV). UVOT took a finding chart exposure of 150 seconds with the White filter starting 180 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 100% of the XRT 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 XRT 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 0.05. Burst Advocate for this burst is J.D. Gropp (jdg44 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: 23643 SUBJECT: GRB 190109A: Prompt enhanced Swift-XRT position DATE: 19/01/09 05:49:48 GMT FROM: Phil Evans at U of Leicester P.A. Evans (U. Leicester) reports on behalf of the Swift-XRT team: Using promptly downlinked XRT event data for GRB 190109A, we find an enhanced XRT position of the afterglow: RA, Dec: 33.2020, 38.1081 which is equivalent to: RA (J2000) = 02 12 48.48 Dec (J2000) = +38 06 29.1 with an uncertainty of 2.0 arcseconds (radius, 90% confidence). Analysis of the promptly available data is online at http://www.swift.ac.uk/sper/882747. Position enhancement is is described by Goad et al. (2007, A&A, 476, 1401) and Evans et al. (2009, MNRAS, 397, 1177). This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23644 SUBJECT: GRB 190109A: Enhanced Swift-XRT position DATE: 19/01/09 10:51:14 GMT FROM: Phil Evans at U of Leicester J.P. Osborne, A.P. Beardmore, P.A. Evans and M.R. Goad (U. Leicester) report on behalf of the Swift-XRT team. Using 1045 s of XRT Photon Counting mode data and 1 UVOT images for GRB 190109A, 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 = 33.20216, +38.10852 which is equivalent to: RA (J2000): 02h 12m 48.52s Dec (J2000): +38d 06' 30.7" 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: 23645 SUBJECT: GRB 190109A: Swift-XRT refined Analysis DATE: 19/01/09 11:25:39 GMT FROM: Phil Evans at U of Leicester A.P. Beardmore (U. Leicester), P.A. Evans (U. Leicester), A. D'Ai (INAF-IASFPA), A. Melandri (INAF-OAB), P. D'Avanzo (INAF-OAB), A. Tohuvavohu (PSU), S. J. LaPorte (PSU), J.A. Kennea (PSU), J.P. Osborne (U. Leicester) and J.D. Gropp report on behalf of the Swift-XRT team: We have analysed 6.1 ks of XRT data for GRB 190109A (Gropp et al. GCN Circ. 23642), from 175 s to 13.0 ks after the BAT trigger. The data comprise 291 s in Windowed Timing (WT) mode with the remainder in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Osborne et al. (GCN Circ. 23643). The late-time light curve (from T0+4.8 ks) can be modelled with a power-law decay with a decay index of alpha=0.8 (+/-0.3). A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 1.87 (+/-0.04). The best-fitting absorption column is 9.5 (+1.3, -1.2) x 10^20 cm^-2, in excess of the Galactic value of 5.1 x 10^20 cm^-2 (Willingale et al. 2013). The PC mode spectrum has a photon index of 1.88 (+0.11, -0.09) and a best-fitting absorption column consistent with the Galactic value. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.5 x 10^-11 (3.8 x 10^-11) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Total column: 5.1 (+2.1, -0.0) x 10^20 cm^-2 Galactic foreground: 5.1 x 10^20 cm^-2 Excess significance: <1.6 sigma Photon index: 1.88 (+0.11, -0.09) If the light curve continues to decay with a power-law decay index of 0.8, the count rate at T+24 hours will be 0.010 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 3.6 x 10^-13 (4.0 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/00882747. This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23649 SUBJECT: GRB190109A: MITSuME Akeno optical upper limits DATE: 19/01/09 12:34:19 GMT FROM: Motoki Oeda at Tokyo Inst. of Tech. M. Oeda, R. Adachi, K. L. Murata, R. Itoh, Y. Tachibana, S. Harita, K. Morita, K.Shiraishi, K. Iida, M. Niwano, Y. Yatsu, and N. Kawai (TokyoTech) report on behalf of the MITSuME collaboration: We searched for the optical counterpart of GRB 190109A (M. J. Moss et al.,GCN Circular #23642) 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 08:18:30.05 UT. We did not find any new point source within the enhanced XRT circle (P.A. Evans et al., GCN Circular #23643) in all three bands. We obtained following 3 sigma limits for the magnitudes. T0+[hour] MID-UT T-EXP[sec] g' Rc Ic ------------------------------------------------------------------------------------------------------- 3.097 8:42:32.91 1140 >16.23 >15.42 >15.34 ------------------------------------------------------------------------------------------------------- T0+ : Elapsed time after the burst T-EXP: Total Exposure time We used GSC2.3 catalog for flux calibration. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23653 SUBJECT: GRB 190109A: Swift-BAT refined analysis DATE: 19/01/09 15:23:32 GMT FROM: Scott Barthelmy at NASA/GSFC T. Sakamoto (AGU), S. D. Barthelmy (GSFC), J. R. Cummings (CPI), J. D. Gropp (PSU), H. A. Krimm (NSF/USRA), A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), D. M. Palmer (LANL), M. Stamatikos (OSU), T. N. Ukwatta (LANL) (i.e. the Swift-BAT team): Using the data set from T-239 to T+963 sec from the recent telemetry downlink, we report further analysis of BAT GRB 190109A (trigger #882747) (Gropp, et al., GCN Circ. 23642). The BAT ground-calculated position is RA, Dec = 33.213, 38.111 deg, which is RA(J2000) = 02h 12m 51.2s Dec(J2000) = +38d 06' 39.5" with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment). The partial coding was 28%. The mask-weighted light curve shows several overlapping peaks starting at ~T+1 sec, peaking at ~T+40 sec, and returning to baseline at ~T+200 sec. T90 (15-350 keV) is 115.0 +- 33.5 sec (estimated error including systematics). The time-averaged spectrum from T+5.86 to T+205.36 sec (with a 1.03 sec gap in the data at T+111.97 sec) is best fit by a power law with an exponential cutoff. This fit gives a photon index 0.36 +- 0.47, and Epeak of 49.7 +- 4.0 keV (chi squared 46.05 for 56 d.o.f.). For this model the total fluence in the 15-150 keV band is 5.5 +- 0.3 x 10^-6 erg/cm2 and the 1-sec peak flux measured from T+38.82 sec in the 15-150 keV band is 1.9 +- 0.3 ph/cm2/sec. A fit to a simple power law gives a photon index of 1.86 +- 0.08 (chi squared 87.76 for 57 d.o.f.). 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/882747/BA/ //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23658 SUBJECT: GRB 190109A: Fermi GBM observation DATE: 19/01/09 16:56:02 GMT FROM: Andreas von Kienlin at MPE A. von Kienlin (MPE) reports on behalf of the Fermi GBM Team: "At 05:12:49.45 UT on 09 January 2019, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 190109A (trigger 568703574 / 190109217), which was also detected by the Swift/BAT (Gropp et al. 2019, GCN 23642) The GBM on-ground location is consistent with the Swift position. The angle from the Fermi LAT boresight at the GBM trigger time is 65 degrees. The GBM light curve shows a structured emission with a duration (T90) of about 120 s (50-300 keV). The time-averaged spectrum from T0-4.096 s to T0+114.690 s is best fit by a Band function with Epeak = 46.8 +/- 2.2 keV, alpha = 1.3 +/- 0.3, and beta = -2.71 +/- 0.13 The event fluence (10-1000 keV) in this time interval is (7.6 +/- 0.4)E-06 erg/cm^2. The 1.024-sec peak photon flux measured starting from T0+30.91 s in the 10-1000 keV band is 2.6 +/- 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: 23663 SUBJECT: GRB 190109A: Swift/UVOT Upper Limits DATE: 19/01/09 20:36:24 GMT FROM: Kira Simpson at PSU GRB 190109A: Swift/UVOT Upper Limits K. K. Simpson (PSU) and J. D. Gropp (PSU) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 190109A 181 s after the BAT trigger (Gropp et al., GCN Circ. 23642). No optical afterglow consistent with the XRT position (Osborne et al. GCN Circ. 23644) 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 181 331 147 >99.0 u_FC 340 590 246 >17.3 white 181 12997 1291 >99.0 v 670 6867 490 >16.8 b 596 18739 1727 >18.6 u 340 24226 2551 >17.5 w1 720 23954 2223 >17.4 m2 695 23048 1357 >18.1 w2 646 6662 491 >17.9 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.05 in the direction of the burst (Schlegel et al. 1998). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23673 SUBJECT: Correction to GCN Circular 23663: GRB 190109A: Swift UVOT Upper Limits DATE: 19/01/11 15:01:41 GMT FROM: Kira Simpson at PSU The values for magnitude UVOT's white filter were listed as 99th magnitude in the previous circular and have been corrected here. GRB 190109A: Swift/UVOT Upper Limits K. K. Simpson (PSU) and J. D. Gropp (PSU) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 190109A 181 s after the BAT trigger (Gropp et al., GCN Circ. 23642). No optical afterglow consistent with the XRT position (Osborne et al. GCN Circ. 23644) 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 181 331 147 >21.60 white 181 12997 1291 >20.27 v 670 6867 490 >16.8 b 596 18739 1727 >18.6 u 340 24226 2551 >17.5 w1 720 23954 2223 >17.4 m2 695 23048 1357 >18.1 w2 646 6662 491 >17.9 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.05 in the direction of the burst (Schlegel et al. 1998).