//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 20131 SUBJECT: GRB 161105A: Swift detection of a burst DATE: 16/11/05 05:14:04 GMT FROM: Kim Page at U.of Leicester K. L. Page (U Leicester), A. Y. Lien (GSFC/UMBC), D. M. Palmer (LANL) and M. H. Siegel (PSU) report on behalf of the Swift Team: At 04:53:02 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 161105A (trigger=720697). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 120.163, -44.780 which is RA(J2000) = 08h 00m 39s Dec(J2000) = -44d 46' 46" 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 140 sec. The peak count rate was ~2500 counts/sec (15-350 keV), at ~8 sec after the trigger. The XRT began observing the field at 04:54:10.1 UT, 67.8 seconds after the BAT trigger. Using promptly downlinked data we find a bright, uncatalogued X-ray source with an enhanced position: RA, Dec 120.1839, -44.7753 which is equivalent to: RA(J2000) = 08h 00m 44.14s Dec(J2000) = -44d 46' 31.1" with an uncertainty of 2.6 arcseconds (radius, 90% containment). This location is 56 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. We cannot determine whether the source is fading at the present time. A power-law fit to a spectrum formed from promptly downlinked event data gives a column density consistent with the Galactic value of 4.15 x 10^21 cm^-2 (Willingale et al. 2013). The initial flux in the 2.5 s image was 3.12e-09 erg cm^-2 s^-1 (0.2-10 keV). UVOT took a finding chart exposure of 150 seconds with the White filter starting 586 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 0.32. Burst Advocate for this burst is K. L. Page (klp5 AT leicester.ac.uk). 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: 20133 SUBJECT: GRB 161105A: MASTER-IAC early optical observations DATE: 16/11/05 10:56:14 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, E.Gorbovskoy, N.Tyurina, V.Kornilov, O.Gress, P.Balanutsa, A.Kuznetsov, D.Kuvshinov Lomonosov Moscow State University, Sternberg Astronomical Institute R. Rebolo, M. Serra Ricart, N. Lodieu, G. Israelian The Instituto de Astrofisica de Canarias R.Podesta, C.Lopez, F.Podesta Observatorio Astronomico Felix Aguilar (OAFA), San Juan Univerdity, H. Levato, C. Saffe Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE) D.Buckley, S. Potter, South African Astronomical Observatory O.Gres, K.Ivanov, J.Rabinovich, N.M.Budnev, Irkutsk State University A. Tlatov, V.Senik, D. Dormidontov, A.Parkhomenko Kislovodsk Solar Station of the Pulkovo Observatory V.Yurkov, Yu.Sergienko, A.Gabovich Blagoveschensk Educational State University, Blagoveschensk MASTER II robotic telescope (MASTER-Net: http://observ.pereplet.ru) located in IAC was pointed to the GRB161105A 27 sec after notice time and 42 sec after trigger time at 2016-11-05 04:53:44 UT. On our first (10s exposure) set we haven`t found optical transient within SWIFT error-box (ra=120.163 dec=-44.7794 r=0.05) (Page et al., GCN 20131). The 5-sigma upper limit has been about 16.4 mag (polaroid, unfiltered). The observations made on zenit distance = 75 degrees, galaxy latitude b = -7 degree. The moon (25 % bright part) below the horizon (The altitude of the Moon is -80 degree ). The sun altitude is -32.4 degree. The object can be observed till sunrise at 2016-11-05 07:20:31 Maximal coadded limit ~19.5 m. No OT found. The message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 20135 SUBJECT: GRB 161105A: Enhanced Swift-XRT position DATE: 16/11/05 16:45:10 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 2913 s of XRT Photon Counting mode data and 6 UVOT images for GRB 161105A, 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 = 120.18375, -44.77529 which is equivalent to: RA (J2000): 08h 00m 44.10s Dec (J2000): -44d 46' 31.0" 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: 20136 SUBJECT: GRB 161105A: Swift-BAT refined analysis DATE: 16/11/05 17:50:26 GMT FROM: Amy Lien at GSFC C. B. Markwardt (GSFC), S. D. Barthelmy (GSFC), J. R. Cummings (GSFC/UMBC), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), A. Y. Lien (GSFC/UMBC), D. M. Palmer (LANL), K. L. Page (U Leicester), T. Sakamoto (AGU), 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 161105A (trigger #720697) (Page et al. GCN Circ. 20131). The BAT ground-calculated position is RA, Dec = 120.198, -44.763 deg which is RA(J2000) = 08h 00m 47.5s Dec(J2000) = -44d 45' 47.6" with an uncertainty of 1.2 arcmin, (radius, sys+stat, 90% containment). The partial coding was 85%. The mask-weighted light curve shows a multi-peaked structure that starts at ~T-90 s and ends at ~T+160 s. There are roughly two main pulses in the structure. The first one contains two obvious peaks at ~T0 and ~T+10s, and the second one peaks at ~T+50 s. T90 (15-350 keV) is 177.3 +- 25.8 sec (estimated error including systematics). The time-averaged spectrum from T-88.00 to T+164.81 sec is best fit by a power law with an exponential cutoff. This fit gives a photon index 1.02 +- 0.24, and Epeak of 159.1 +- 135.3 keV (chi squared 55.64 for 56 d.o.f.). For this model the total fluence in the 15-150 keV band is 6.1 +- 0.2 x 10^-6 erg/cm2 and the 1-sec peak flux measured from T+0.63 sec in the 15-150 keV band is 1.4 +- 0.2 ph/cm2/sec. A fit to a simple power law gives a photon index of 1.35 +- 0.06 (chi squared 61.67 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/720697/BA/ //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 20138 SUBJECT: GRB 161105A: Swift-XRT refined Analysis DATE: 16/11/06 05:13:05 GMT FROM: Phil Evans at U of Leicester T.G.R. Roegiers (PSU), L.M. McCauley (PSU), A.P. Beardmore (U. Leicester), P.A. Evans (U. Leicester), S.L. Gibson (U. Leicester), P. D'Avanzo (INAF-OAB), V. D'Elia (ASDC), A. D'Ai (INAF-IASFPA), J.A. Kennea (PSU) and K.L. Page report on behalf of the Swift-XRT team: We have analysed 5.0 ks of XRT data for GRB 161105A (Page et al. GCN Circ. 20131), from 560 s to 23.3 ks after the BAT trigger. The data are entirely in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Osborne et al. (GCN Circ. 20135). The light curve can be modelled with an initial power-law decay with an index of alpha=4.6 (+/-1.2), followed by a break at T+909 s to an alpha of 0.86 (+0.14, -0.15). A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 1.90 (+0.28, -0.15). The best-fitting absorption column is consistent with the Galactic value of 4.1 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 4.1 x 10^-11 (5.8 x 10^-11) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Total column: 4.1 (+/-1.1) x 10^21 cm^-2 Galactic foreground: 4.1 x 10^21 cm^-2 Excess significance: <1.6 sigma Photon index: 1.90 (+0.28, -0.15) If the light curve continues to decay with a power-law decay index of 0.86, the count rate at T+24 hours will be 4.5 x 10^-3 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.8 x 10^-13 (2.6 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/00720697. This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 20152 SUBJECT: GRB 161105A: TAROT La Silla observatory optical observations DATE: 16/11/08 22:25:29 GMT FROM: Alain Klotz at IRAP-CNRS-OMP Klotz A., Turpin D., Atteia J.L. (CNRS-OMP-IRAP), Boer, M., Laugier, R. (CNRS-ARTEMIS), Gendre B. (UVI - Etelman Obs.) report: We imaged the field of GRB 161105A detected by SWIFT (trigger 720697) with the TAROT robotic telescope (D=25cm) located at the European Southern Observatory, La Silla observatory, Chile. The observations started 27.4s after the GRB trigger (14.8s after the notice). The elevation of the field increased from 31 degrees above horizon and weather conditions were excellent. The first image is trailed with a duration of 60.0s (see the description in Klotz et al., 2006, A&A 451, L39). We do not detect any OT (in the XRT error box provided by Page et al. GCNC 20131) with a limiting magnitude of: t0+27.4s to t0+87.4s : Rlim = 16.5 Due to technical problems the second image was taken only 743 seconds after the GRB: t0+743.2s to t0+833.2s : Rlim = 19.8 No more candidate were found in the next images taken until 2000 seconds after the GRB at the same limiting magnitude. Magnitudes were estimated with the nearby NOMAD1 stars and are not corrected for galactic dust extinction. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 20157 SUBJECT: GRB 161105A: Swift/UVOT Upper Limits DATE: 16/11/09 17:08:21 GMT FROM: Mike Siegel at PSU/Swift MOC M. H. Siegel (PSU) and K. L. Page (U. Leicester) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 161105A 586 s after the BAT trigger (Page et al., GCN Circ. 20131). No optical afterglow consistent with the XRT position (Osborne et al. GCN Circ. 20135) 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 initial exposures are: Filter T_start(s) T_stop(s) Exp(s) Mag white (fc) 586 735 147 >20.44 white 586 5286 549 >21.11 v 1046 7179 274 >18.86 b 841 5081 274 >20.07 u 816 1652 86 >18.62 uvw1 792 11242 713 >19.91 uvm2 767 7384 293 >19.12 uvw2 1022 6974 290 >19.24 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.33 in the direction of the burst (Schlegel et al. 1998).