//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11553 SUBJECT: GRB 110112A: Swift detection of a possible short burst DATE: 11/01/12 04:26:58 GMT FROM: Michael Stamatikos at OSU/GSFC M. Stamatikos (OSU/NASA/GSFC), A. P. Beardmore (U Leicester), J. R. Cummings (NASA/UMBC), J. M. Gelbord (PSU), S. T. Holland (CRESST/USRA/GSFC), J. A. Kennea (PSU), O. M. Littlejohns (U Leicester), K. L. Page (U Leicester), J. L. Racusin (NASA/GSFC), T. Sakamoto (NASA/UMBC), M. H. Siegel (PSU), E. Sonbas (GSFC/USRA/Adiyaman Univ.) and E. Troja (NASA/GSFC/ORAU) report on behalf of the Swift Team: At 04:12:18 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 110112 A (trigger=442039). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 329.941, +26.489 which is RA(J2000) = 21h 59m 46s Dec(J2000) = +26d 29' 20" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a single peak with a duration of about 2 sec. The peak count rate was ~1700 counts/sec (15-350 keV), at the trigger time. The XRT began observing the field at 04:13:33.9 UT, 75.5 seconds after the BAT trigger. Using promptly downlinked data we find an uncatalogued X-ray source with an enhanced position: RA, Dec 329.9330, 26.4564 which is equivalent to: RA(J2000) = 21h 59m 43.91s Dec(J2000) = +26d 27' 23.0" with an uncertainty of 2.7 arcseconds (radius, 90% containment). This location is 119 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 5.54 x 10^20 cm^-2 (Kalberla et al. 2005). UVOT took a finding chart exposure of 150 seconds with the White filter starting 80 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 none of the XRT error circle. The coverage of the XRT error circle by the 8'x8' region for the list of sources generated on-board is uncertain because the large number of sources filled the available telemetry. No correction has been made for the expected extinction corresponding to E(B-V) of 0.06. Burst Advocate for this burst is M. Stamatikos (Michael.Stamatikos-1 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: http://www.swift.psu.edu/too.html.) //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11554 SUBJECT: GRB110112A: TNT optical afterglow candidate DATE: 11/01/12 13:17:22 GMT FROM: L.P. Xin at NAOC L.P. Xin, T. M. Zhang, Y.L. Qiu, J.Y. Wei, J. Wang, J.S. Deng, C. Wu, X. H. Han on behalf of EAFON report: We began to observe GRB110112A (stamatikos et al., GCN 11553 ) with Xinglong TNT telescope at 10:08:35.375 (UT), 6 hours after the burst. 16 images in R-band were obtained with an exposure time of 300 sec for each frame. After combining all these images, a new marginal source was found within the errorbox of X-ray counterpart ( stamatikos et al., GCN 11553). Its coordinates ( RA and Dec ) are 21:59:43.8 26:27:25.9 (J2000) with an uncertainty of about 1 arcsecond. The brightness of the source is estimated to be about 19.6 +/- 0.3 mag which is derived from USNO B1.0 R2 mag at the mean time of 6.5 hour after the burst. Further observations and confirmation are encouraged. This message may be cited. For more information about Xinglong GRBs Follow-up observations, please visit the website: http://www.xinglong-naoc.org/grb/ //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11556 SUBJECT: GRB 110112A: Enhanced Swift-XRT position DATE: 11/01/12 16:00:11 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 1127 s of XRT Photon Counting mode data and 2 UVOT images for GRB 110112A, 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 = 329.93240, +26.45636 which is equivalent to: RA (J2000): 21h 59m 43.77s Dec (J2000): +26d 27' 22.9" with an uncertainty of 3.2 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: 11557 SUBJECT: GRB 110112A: Swift-BAT refined analysis DATE: 11/01/12 16:32:56 GMT FROM: Scott Barthelmy at NASA/GSFC S. D. Barthelmy (GSFC), T. Sakamoto (GSFC/UMBC), M. Stamatikos (OSU) (on behalf of the Swift-BAT team): Using the data set from T-60 to T+123 sec from the recent telemetry downlink, we report further analysis of BAT short GRB 110112A (trigger #442039) (Stamatikos, et al., GCN Circ. 11553). The BAT ground-calculated position is RA, Dec = 329.936, 26.470 deg, which is RA(J2000) = 21h 59m 44.6s Dec(J2000) = +26d 28' 10.6" with an uncertainty of 2.6 arcmin, (radius, sys+stat, 90% containment). The partial coding was 87%. The mask-weighted light curve shows a single spike starting at ~T-0.1 sec and ending at ~T+0.5 sec. T90 (15-350 keV) is 0.5 +- 0.1 sec (estimated error including systematics). The time-averaged spectrum from T-0.1 to T+0.5 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 2.14 +- 0.46. The fluence in the 15-150 keV band is 3.0 +- 0.9 x 10^-8 erg/cm2. The 1-sec peak photon flux measured from T-0.28 sec in the 15-150 keV band is 0.5 +- 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/442039/BA/ //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11558 SUBJECT: GRB 110112A: MASTER optical observations DATE: 11/01/12 18:20:16 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs E. Gorbovskoy, V. Lipunov, V.Kornilov, A.Belinski, N.Shatskiy, N.Tyurina, D.Kuvshinov, P.Balanutsa, V.V.Chazov, P.V.Kortunov, A.Kuznetsov, D.Zimnukhov, M. Kornilov, V.Shumkov, S.Shurpakov Sternberg Astronomical Institute, Moscow State University V.Krushinski, I.Zalozhnich, A. Popov Ural State University, Kourovka K.Ivanov, O.Chuvalaev, V.Poleschuk, E.Konstantinov, V.Lenok, O.Gres, S.Yazev, N.M.Budnev, Irkutsk State University A. Tlatov, A.V. Parhomenko, D. Dormidontov, V.Sennik Kislovodsk Solar Station of the Pulkovo Observatory V.Yurkov, Yu.Sergienko, D.Varda, I.Kudelina Blagoveschensk Educational State University, Blagoveschensk MASTER II robotic telescope (MASTER-Net: http://observ.pereplet.ru) located in Kislovodsk was pointed to the GRB110112.18 48131 sec s after notice time and 48156 sec after GRB time at 2011-01-12 17:34:54.665 UT. On our first (180s exposure) set we haven`t found optical transient within SWIFT error-box (ra=21 59 45 dec=+26 29 24 r=0.050000). The 5-sigma upper limit has been about 18.3 mag (V) and 19.0 (R). The message generated automaticaly. cited. mailto: lipunov@sai.msu.ru //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11559 SUBJECT: GRB 110112A: WHT candidate afterglow/host galaxy DATE: 11/01/12 22:52:49 GMT FROM: Andrew Levan at U.of Leicester A.J. Levan (U. Warwick), N.R. Tanvir (U. Leicester), D. Baker (U. Leicester/U. Hertfordshire) report for a larger collaboration: "We observed the field of the short GRB 110112A (Stamatikos et al. GCN 11553) with ACAM mounted on the William Herschel Telescope (WHT) on La Palma. Observations began 15.5 hours after the GRB. Within the XRT localization (Evan et al. GCN 11556) we detect a faint, possibly extended source at a position of RA(J2000) 21:59:43.84 DEC(J2000) 26:27:24.0 with an error of ~0.5" in each axis The source has a magnitude of i~22, calibrated against nearby stars from the USNO B1 catalog. This magnitude is fainter than that inferred for a candidate afterglow of Xin et al. (GCN 11554), suggestive of fading between the two epochs. We note that the positions of the two objects are only marginally consistent with each other, and suggest that the source observed in our WHT observations is a candidate host galaxy for GRB 110112A, although with a single epoch we cannot constrain any possible afterglow contribution at this time." //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11560 SUBJECT: GRB 110112A: Swift/UVOT upper limits DATE: 11/01/12 22:53:06 GMT FROM: Alice Breeveld at MSSL-UCL A. A. Breeveld (MSSL/UCL) and M. Stamatikos (OSU/NASA/GSFC) report on behalf of the Swift/UVOT team: Swift UVOT started observing the field of GRB 110112A with the white filter 85s after the trigger (Stamatikos et al., GCN Circ. 11553). No optical afterglow consistent with the TNT or XRT positions (Xin et al., CGN Circ. 11554 and Evans et al., GCN Circ. 11556) is detected in individual or merged UVOT exposures. Preliminary 3-sigma upper limits using the UVOT photometric system (Poole et al. 2008, MNRAS, 383, 627) are: Filter T_start T_stop Exp(s) Mag (Upper limits) --------------------------------------------------------------------------- white 85 235 147 >20.4 white 4499 6134 393 >21.3 v 4909 6544 393 >19.6 b 4294 5929 393 >20.3 u 287 5724 639 >20.2 uvw1 5319 5519 19.7 >18.8 uvm2 5079 6634 280 >18.9 uvw2 4705 6339 393 >19.2 ---------------------------------------------------------------------------- The quoted upper limits have not been corrected for the expected Galactic extinction along the line of sight corresponding to a reddening of E_{B-V} = 0.06 mag (Schlegel et al., 1998, ApJS, 500, 525). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11561 SUBJECT: GRB 110112A: Swift-XRT refined Analysis DATE: 11/01/12 23:05:48 GMT FROM: Andy Beardmore at U Leicester A. P. Beardmore (U. Leicester) and M. Stamatikos (OSU/NASA/GSFC) report on behalf of the Swift-XRT team: We have analysed 23 ks of XRT data for GRB 110112A (Stamatikos et al. GCN Circ. 11553), from 82 s to 52.8 ks after the BAT trigger. The data are entirely in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Evans et al. (GCN. Circ 11556). The light curve can be modelled with a power-law decay with a decay index of alpha=0.95 +/- 0.05. A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 2.3 (+0.4, -0.3). The best-fitting absorption column is 1.4 (+0.8, -0.7) x 10^21 cm^-2, in excess of the Galactic value of 5.5 x 10^20 cm^-2 (Kalberla et al. 2005). The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.4 x 10^-11 (5.4 x 10^-11) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Total column: 1.4 (+0.8, -0.7) x 10^21 cm^-2 Galactic foreground: 5.5 x 10^20 cm^-2 Excess significance: 3.0 sigma Photon index: 2.3 (+0.4, -0.3) The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00442039. This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11566 SUBJECT: GRB 110112A: MITSuME Akeno and Okayama optical upper limits DATE: 11/01/14 09:21:44 GMT FROM: Daisuke Kuroda at OAO/NAOJ H. Nakajima (Tokyo Tech), D. Kuroda, K. Yanagisawa, Y. Shimizu, H. Toda (OAO, NAOJ), S. Nagayama (NAOJ), M. Yoshida (Hiroshima), K. Ohta (Kyoto), Y. Yatsu, T. Enomoto, K. Kawakami, K. Tokoyoda, T. Ohkawa and N. Kawai(Tokyo Tech) report on behalf of the MITSuME collaboration: We observed the field of GRB 110112A (Stamatikos et al.,GCN 11553) with the optical three color (g', Rc and Ic) CCD camera attached to the MITSuME 50cm telescope of Akeno Observatory and Okayama Astrophysical Observatory. We did not find any new point source within the enhanced XRT error circle (Evans et al., GCN 11556) in all the three bands. We could not detect the previously reported afterglow (Xin et al., GCN 11554). Three sigma upper limits of the OT are listed below. We used GSC2.3 catalog for flux calibration. Akeno Observatory: The observation started on 2011-01-12 09:07:48 UT (~5 h after the trigger). T0+[day] MID-UT T-EXP[sec] g' Rc Ic ------------------------------------------------------ 0.21513 09:22:06 1200.0 >20.2 >20.0 >19.4 ------------------------------------------------------ T0+ : Elapsed time after the burst [day] T-EXP: Total Exposure time [sec] Okayama Astrophysical Observatory: The observation started on 2011-01-12 09:15:35 UT (~5.1 h after the trigger). T0+[day] MID-UT T-EXP[sec] g' Rc Ic ------------------------------------------------------ 0.23603 09:52:11 3840.0 >19.9 >19.8 >19.3 ------------------------------------------------------ T0+ : Elapsed time after the burst [day] T-EXP: Total Exposure time [sec] //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11589 SUBJECT: GRB 110112A: optical upper limit DATE: 11/01/20 21:37:07 GMT FROM: Alexei Pozanenko at IKI, Moscow K. Grankin, V. Rumyantsev (CrAO), A. Pozanenko (IKI) report on behalf of larger GRB follow-up collaboration: We observed the field of the Swift GRB 110112A (Stamatikos et al., GCN 11553) with AZT-11 telescope of CrAO starting on Jan. 12 (UT) 16:35. In the enhanced Swift-XRT position (Evanset al., GCN 11556) we do not detect optical afterglow (Xin et al., GCN 11554) up to R=20.6. The photometry is based on the USNO B1.0 star 1164-0563915 (21 59 45.42 +26 27 18.3) assuming R=15.64. T0+ Filter, Exposure, mag. (mid, d) (s) 0.52955 R 13x180 R >20.6 //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11619 SUBJECT: GRB110112A: EVLA Observations DATE: 11/01/31 17:26:28 GMT FROM: Ashley Zauderer at CfA A. Zauderer, E. Berger, and W. Fong (Harvard) report: We observed the position of the short GRB 110112A (GCN #11553) with the EVLA for 1 hour at 5 GHz starting on 2011 January 14.05 UT (1.87 days after the burst). No radio source is detected within the XRT error circle (GCN #11556) to a 3-sigma limit of 75 microJy. We acknowledge the EVLA staff for their support of these observations.