//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 19522 SUBJECT: GRB 160611A: Swift detection of a burst DATE: 16/06/11 21:49:29 GMT FROM: Scott Barthelmy at NASA/GSFC D. Malesani (DARK/NBI), S. D. Barthelmy (GSFC), D. M. Palmer (LANL) and M. H. Siegel (PSU) report on behalf of the Swift Team: At 21:40:34 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 160611A (trigger=690598). Swift did not slew due to an observing constraint. The BAT on-board calculated location is RA, Dec 164.438, -70.395, which is RA(J2000) = 10h 57m 45s Dec(J2000) = -70d 23' 40" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve shows multiple peaks with a duration of about 30 sec. The peak count rate was ~2000 counts/sec (15-350 keV), at ~4 sec after the trigger. Due to an observing constraint, Swift will not slew until T0+43.3 minutes. There will be no XRT or UVOT data until this time. Burst Advocate for this burst is D. Malesani (malesani AT dark-cosmology.dk). 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: 19523 SUBJECT: GRB 160611A: Swift-XRT observations DATE: 16/06/11 23:00:57 GMT FROM: Phil Evans at U of Leicester J.P. Osborne (U. Leicester), D.N. Burrows (PSU), J.A. Kennea (PSU), G. Tagliaferri (INAF-OAB), S. Campana (INAF-OAB) and P.A. Evans (U. Leicester) report on behalf of the Swift-XRT team: The XRT began observing the field of GRB 160611A at 22:25:16.5 UT, 2682.1 seconds after the BAT trigger. Using promptly downlinked data we find an uncatalogued X-ray source located at RA, Dec 164.42342, -70.39301 which is equivalent to: RA(J2000) = 10h 57m 41.62s Dec(J2000) = -70d 23' 34.8" with an uncertainty of 3.6 arcseconds (radius, 90% containment). This location is 19 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. A power-law fit to a spectrum formed from promptly downlinked event data gives a column density in excess of the Galactic value (1.70 x 10^21 cm^-2, Willingale et al. 2013), with an excess column of 7.6 (+2.39/-2.15) x 10^21 cm^-2 (90% confidence). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 19524 SUBJECT: GRB 160611A: Enhanced Swift-XRT position DATE: 16/06/12 05:32:33 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 4788 s of XRT Photon Counting mode data and 10 UVOT images for GRB 160611A, 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 = 164.42229, -70.39243 which is equivalent to: RA (J2000): 10h 57m 41.35s Dec (J2000): -70d 23' 32.7" with an uncertainty of 1.5 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: 19525 SUBJECT: GRB160611.9 MASTER-Net OT detection DATE: 16/06/12 06:00:17 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, E. Gorbovskoy, N.Tyurina, V.Kornilov, P.Balanutsa, A.Kuznetsov, D.Kuvshinov, Lomonosov Moscow State University, Sternberg Astronomical Institute D.Buckley, S. Potter, A.Kniazev, M.Kotze South African Astronomical Observatory K.Ivanov, S.Yazev, N.M.Budnev, O.Gres, O.Chuvalaev, V.A.Poleshchuk Irkutsk State University A. Tlatov, A.V. Parhomenko, D. Dormidontov, V.Senik Kislovodsk Solar Station of the Pulkovo Observatory V.Yurkov, Yu.Sergienko, D.Varda, E.Sinyakov Blagoveschensk Educational State University, Blagoveschensk V.Krushinski, I.Zalozhnih, A. Popov Ural Federal University, Kourovka Hugo Levato and Carlos Saffe Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE) Claudio Mallamaci, Carlos Lopez and Federico Podest Observatorio Astronomico Felix Aguilar (OAFA) R. Rebolo, M. Serra, N. Lodieu, G. Israelian, L. Suarez-Andres The Instituto de Astrofisica de Canarias MASTER II robotic telescope (MASTER-Net: http://observ.pereplet.ru) located in SAAO was pointed to the GRB160611.9 24 sec after notice time and 54 sec after trigger time at 2016-06-11 21:41:28 UT. On our first (10s exposure) set we found 1 optical transient within SWIFT error-box (ra=10 57 45 dec=-70 23 41 r=0.050000) brighter then 15. T-Tmid Date Time Expt. Ra Dec Mag ---------|---------------------|-------|-----------------|-----------------|------- 59 2016-06-11 21:41:28 10 (10h 57m 57.87s , -70d 24m 47.1s) 14.67 The 5-sigma upper limit has been about 15mag The message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 19526 SUBJECT: GRB 160611A: GCN19525 OT is known star DATE: 16/06/12 08:33:51 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov (MASTER, LMSU) The OT wich published in GCN 19525 is the result of the false identification. I am sorry for my mistake. The message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 19527 SUBJECT: GRB 160611A: Swift-XRT refined Analysis DATE: 16/06/12 12:58:59 GMT FROM: Phil Evans at U of Leicester T.G.R. Roegiers (PSU), L.M. McCauley (PSU), J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), B. Mingo (U. Leicester), P. D'Avanzo (INAF-OAB), V. D'Elia (ASDC), A. D'Ai (INAF-IASFPA), J.A. Kennea (PSU) and D. Malesani report on behalf of the Swift-XRT team: We have analysed 7.9 ks of XRT data for GRB 160611A (Malesani et al. GCN Circ. 19522), from 2.7 ks to 44.8 ks after the BAT trigger. The data comprise 50 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. 19524). The light curve can be modelled with a series of power-law decays. The initial decay index is alpha=1.54 (+0.48, -0.21). At T+5128 s the decay flattens to an alpha of -0.7 (+1.3, -0.8) before breaking again at T+7161 s to a final decay with index alpha=1.28 (+0.10, -0.09). A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 2.01 (+0.12, -0.11). The best-fitting absorption column is 5.0 (+0.7, -0.6) x 10^21 cm^-2, in excess of the Galactic value of 1.7 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 (6.6 x 10^-11) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Total column: 5.0 (+0.7, -0.6) x 10^21 cm^-2 Galactic foreground: 1.7 x 10^21 cm^-2 Excess significance: 8.5 sigma Photon index: 2.01 (+0.12, -0.11) If the light curve continues to decay with a power-law decay index of 1.28, the count rate at T+24 hours will be 0.021 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 8.4 x 10^-13 (1.4 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/00690598. This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 19529 SUBJECT: GRB 160611A: Swift-BAT refined analysis DATE: 16/06/12 18:47:00 GMT FROM: Hans Krimm at NASA-GSFC T. Sakamoto (AGU), S. D. Barthelmy (GSFC), J. R. Cummings (GSFC/UMBC), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), A. Y. Lien (GSFC/UMBC), D. Malesani (DARK/NBI), C. B. Markwardt (GSFC), 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+962 sec from the recent telemetry downlink, we report further analysis of BAT GRB 160611A (trigger #690598) (Malesani, et al., GCN Circ. 19522). The BAT ground-calculated position is RA, Dec = 164.417, -70.396 deg which is RA(J2000) = 10h 57m 40.0s Dec(J2000) = -70d 23' 45.8" with an uncertainty of 1.2 arcmin, (radius, sys+stat, 90% containment). The partial coding was 45%. The mask-weighted light curve shows a single episode with several overlapping pulses. The emission starts at T-15 sec, peaks at T+3 sec and ends at T+20 sec. T90 (15-350 keV) is 34.1 +- 5.6 sec (estimated error including systematics). A pre-planned spacecraft slew moved the source out of the field of view at about T+165 sec. The time-averaged spectrum from T-31.38 to T+10.37 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.67 +- 0.12. The fluence in the 15-150 keV band is 1.7 +- 0.1 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+2.84 sec in the 15-150 keV band is 2.0 +- 0.3 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/690598/BA/ //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 19530 SUBJECT: GRB 160611A: Swift/UVOT observations DATE: 16/06/12 18:52:25 GMT FROM: Massimiliano de Pasquale at IASF-Palermo M. De Pasquale (UCL-MSSL) and D. Malesani (DARK/NBI) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 160611A 2687 s after the BAT trigger (Malesani et al., GCN Circ. 19522). Very close to the XRT error circle (Osborne et al. GCN Circ. 19523), two sources are detected in the UVOT images. These sources are also detected in the Digitized Sky Survey (DSS) and are listed in the USNO catalog. Their light would blend with any new source at the XRT position, making the analysis more delicate. None of the two sources shows any significant flux decrease in the white filter between the first two white exposures (mid-time: 3071 s after the trigger) and the last three white exposures (mid-time: 10030 s after the trigger). Similarly, we find no significant decrease of the flux of the two sources in the u filter between the first u filter exposure (mid-time: 2946 s) and the last one (mid-time: 8560 s). We conclude that no optical afterglow consistent with the XRT position is detected in the UVOT exposures. Preliminary 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) are: Filter T_start(s) T_stop(s) Exp(s) Mag white 2687 3456 344 >19.6 white 9578 10478 880 >19.8 v 3668 3867 197 >18.1 b 3051 9573 1082 >18.9 u 2846 8660 393 >19.6 w1 4078 5167 191 >19.7 m2 3873 4072 197 >19.4 w2 3463 10905 611 >20.6 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.22 in the direction of the burst (Schlegel et al. 1998).