//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 13049 SUBJECT: GRB 120312A: Swift detection of a burst DATE: 12/03/12 16:33:53 GMT FROM: David Palmer at LANL M. Stamatikos (OSU/NASA/GSFC), S. Campana (INAF-OAB), M. M. Chester (PSU), V. D'Elia (ASDC), N. Gehrels (NASA/GSFC), S. T. Holland (STScI), J. A. Kennea (PSU), V. Mangano (INAF-IASFPA), F. E. Marshall (NASA/GSFC), A. Maselli (INAF-IASFPA), A. Melandri (INAF-OAB), J. P. Osborne (U Leicester), K. L. Page (U Leicester), D. M. Palmer (LANL), P. Romano (INAF-IASFPA), B. Sbarufatti (INAF-OAB/PSU), M. H. Siegel (PSU), M. C. Stroh (PSU), C. A. Swenson (PSU), G. Tagliaferri (INAF-OAB) and B.-B. Zhang (PSU) report on behalf of the Swift Team: At 16:06:28 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 120312A (trigger=517566). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 251.764, +23.857 which is RA(J2000) = 16h 47m 03s Dec(J2000) = +23d 51' 24" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a single-peaked FRED structure with a duration of 12 about sec. The peak count rate was ~1300 counts/sec (15-350 keV), at ~0 sec after the trigger. Using promptly downlinked data we find an uncatalogued X-ray source with an enhanced position: RA, Dec 251.7885, 23.8586 which is equivalent to: RA(J2000) = 16h 47m 09.23s Dec(J2000) = +23d 51' 30.8" with an uncertainty of 2.1 arcseconds (radius, 90% containment). 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 (4.08 x 10^20 cm^-2, Kalberla et al. 2005), with an excess column of 1.7 (+1.51/-1.34) x 10^21 cm^-2 (90% confidence). UVOT took a finding chart exposure of 150 seconds with the White filter starting 112 s 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 0.07. 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: 13052 SUBJECT: GRB 120312A: Swift-BAT refined analysis DATE: 12/03/12 22:24:54 GMT FROM: Scott Barthelmy at NASA/GSFC S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (GSFC/UMBC), G. Sato (ISAS), M. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (MSU) (i.e. the Swift-BAT team): Using the data set from T-240 to T+736 sec from the recent telemetry downlink, we report further analysis of BAT GRB 120312A (trigger #517566) (Stamatikos, et al., GCN Circ. 13049). The BAT ground-calculated position is RA, Dec = 251.812, 23.881 deg, which is RA(J2000) = 16h 47m 14.8s Dec(J2000) = +23d 52' 50.3" with an uncertainty of 2.1 arcmin, (radius, sys+stat, 90% containment). The partial coding was 35%. The mask-weighted light curve shows a single slightly symmetric peak starting at ~T-10 sec, peaking at ~T+0.5 sec, and ending at ~T+35 sec. T90 (15-350 keV) is 14.2 +- 3.4 sec (estimated error including systematics). The time-averaged spectrum from T-1.42 to T+15.87 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.72 +- 0.23. The fluence in the 15-150 keV band is 5.7 +- 0.8 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T+0.95 sec in the 15-150 keV band is 1.3 +- 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/517566/BA/ //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 13053 SUBJECT: GRB 120312A: Swift-XRT refined Analysis DATE: 12/03/13 04:34:08 GMT FROM: Phil Evans at U of Leicester V. Mangano (INAF-IASFPA), A. Melandri (INAF-OAB), B. Sbarufatti (INAF-OAB/PSU), J.A. Kennea (PSU), M.C. Stroh (PSU), D.N. Burrows (PSU), A.P. Beardmore (U. Leicester), P.A. Evans (U. Leicester), O.M. Littlejohns (U. Leicester) and M. Stamatikos report on behalf of the Swift-XRT team: We have analysed 9.9 ks of XRT data for GRB 120312A (Stamatikos et al. GCN Circ. 13049), from 112 s to 19.6 ks after the BAT trigger. The data are entirely in Photon Counting (PC) mode. Using 2188 s of PC mode data and 2 UVOT images, we find an enhanced XRT position (using the XRT-UVOT alignment and matching UVOT field sources to the USNO-B1 catalogue): RA, Dec = 251.78816, +23.85817 which is equivalent to: RA (J2000): 16h 47m 09.16s Dec(J2000): +23d 51' 29.4" with an uncertainty of 1.6 arcsec (radius, 90% confidence). The light curve can be modelled with a power-law decay with a decay index of alpha=1.28 (+0.14, -0.13). A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 1.54 (+0.26, -0.25). The best-fitting absorption column is 1.4 (+0.9, -0.8) x 10^21 cm^-2, in excess of the Galactic value of 4.1 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 4.9 x 10^-11 (5.7 x 10^-11) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Total column: 1.4 (+0.9, -0.8) x 10^21 cm^-2 Galactic foreground: 4.1 x 10^20 cm^-2 Excess significance: 2.1 sigma Photon index: 1.54 (+0.26, -0.25) The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00517566. This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 13054 SUBJECT: GRB 120312A: NOT observations DATE: 12/03/13 04:42:24 GMT FROM: Paul Vreeswijk at U of Iceland Paul Vreeswijk (U. Iceland), Dong Xu (WIS), John Telting, Gintaras Barisevicius (NOT), Daniele Malesani (DARK/NBI), Páll Jakobsson (U. Iceland) report on behalf of a larger collaboration: Using ALFOSC on the Nordic Optical Telescope (NOT) we have obtained r'- (3 x 300 s) and z'-band (6 x 300 s) imaging of the field of the Swift GRB 120312A (Stamatikos et al., GCN 13049; Barthelmy et al., GCN 12052), starting on 2012 March 13.085 UT (9.93 hr after the GRB). The seeing during the observations was around 1". We do not detect any object within the enhanced Swift-XRT error circle (Mangano et al., GCN 13053) down to approximate limiting magnitudes of r'>23.5 and z'>22.2 (calibrated against the SDSS catalog). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 13055 SUBJECT: GRB 120312A: WHT candidate afterglow DATE: 12/03/13 07:36:16 GMT FROM: Nial Tanvir at U.Leicester N. R. Tanvir (U. Leicester), O. Hartoog (U. Amsterdam), and T. Schrabback (U. Bonn) report on behalf of a larger collaboration: We imaged the field of GRB120312A (Stamatikos et al. GCN13049) using the WHT/ACAM beginning 05:15 UT on March 13th (approximately 13 hours post-burst). A 24 minute integration was obtained in the z-band.   Within the refined XRT error circle (Mangano et al. GCN13053) we find a source at position: RA(2000) = 16 47 09.23 dec(2000)= +23 51 28.9 The source may be slightly extended, although the S/N is too poor to determine this with confidence.  Its provisional magnitude is z~23.8 +/- 0.2 calibrated against nearby SDSS DR8 stars. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 13056 SUBJECT: GRB 120312A: MASTER-NET optical observations DATE: 12/03/13 08:29:29 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs K.Ivanov, S.Yazev, N.M.Budnev, O.Gres, O.Chuvalaev, V.A.Poleshchuk Irkutsk State University E. Gorbovskoy, V. Lipunov, V.Kornilov, D.Kuvshinov, A.Belinski, N.Tyurina, N.Shatskiy, P.Balanutsa, D.Zimnukhov, A.Kuznetsov, V.V.Chazov, A.Kuznetsov, A.Sankovich Sternberg Astronomical Institute, Moscow State University V.Yurkov, Yu.Sergienko, D.Varda, E.Sinyakov Blagoveschensk Educational State University, Blagoveschensk A. Tlatov, A.V. Parhomenko, D. Dormidontov, V.Sennik Kislovodsk Solar Station of the Pulkovo Observatory V.Krushinski, I.Zalozhnich, A. Popov Ural Federal University 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) MASTER II robotic telescope (MASTER-Net: http://observ.pereplet.ru) located in Tunka was pointed to the GRB120312A 403 s after notice time and 512 s after GRB time at 2012-03-12 16:15:01 UT in two polarizations. On our first (180s exposure) set we haven`t found optical transient within SWIFT error-box. The 5-sigma upper limit has been about 17.6 mag The object has been observed in high zenit distance (~80 deg). The big time delay (in pointing) is caused by a non-standard format of the socket messages. The message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 13057 SUBJECT: GRB 120312A: Swift/UVOT Upper Limits DATE: 12/03/13 11:11:56 GMT FROM: Samantha Oates at MSSL S. R. Oates (MSSL-UCL) and M. Stamatikos (OSU/NASA/GSFC) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 120312A 105 s after the BAT trigger (Stamatikos et al., GCN Circ. 13049). No optical afterglow consistent with the XRT position (Mangano et al., GCN Circ 13053) or the WHT optical candidate position (Tanvir et al., GCN Circ 13055) 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 105 255 147 >21.3 u_FC 318 567 246 >20.6 white 105 7764 861 >21.9 v 647 18848 1378 >20.5 b 573 7559 568 >20.9 u 318 13854 1583 >21.3 w1 696 13039 1434 >21.0 m2 844 19630 1998 >21.4 w2 795 17934 1434 >21.4 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.071 in the direction of the burst (Schlegel et al. 1998). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 13064 SUBJECT: GRB 120312A: Gemini and UKIRT imaging DATE: 12/03/13 22:57:53 GMT FROM: Nial Tanvir at U.Leicester N. R. Tanvir (U. Leicester), D. Perley (Caltech), K. Wiersema (U. Leicester), A. Cucchiara (UCSC/UCO Lick), K. Roth (Gemini) and J. Ehle (JACH) report on behalf of a larger collaboration: We observed the location of GRB 120312A with Gemini-N/GMOS in the z-band and UKIRT/WFCAM in the J- and K-bands.  All observations were obtained approximately 23 hours post-burst. With GMOS we detect the source reported by Tanvir et al. (GCN 13055). Calibrating against SDSS field stars we find a magnitude z=24.35 +- 0.12, indicating a fading compared to the WHT epoch, and confirming this source as the afterglow of the GRB. From a provisional reduction of the UKIRT data, the afterglow is undetected to 3-sigma limits of J=21.1 and K=19.5 (calibrated against 2MASS), showing that it is not extremely red, as might have been expected if its faintness were due to a very dusty line of sight. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 13065 SUBJECT: GRB 120312A: CrAO optical upper limit DATE: 12/03/14 21:35:32 GMT FROM: Alexei Pozanenko at IKI, Moscow V. Rumyantsev, N. Pit' (CrAO), A. Pozanenko (IKI) report on behalf of larger GRB follow-up collaboration: We observed the field of GRB 120312A (Stamatikos et al., GCN 13049) with AZT-11 telescope of CrAO observatory starting on March 12 (UT) 23:21:13 under moderate weather conditions and seeing of about 2.4 arsces. Within enhanced Swift-XRT position (Mangano et al., GCN 13053) we do not detected any optical source, in particular afterglow candidate (Tanvir et al., GCN 13055). A photometry is based on the USNO-B1.0 star 1138-0244157 (16:47:09.53 +23:51:17.4) assuming R=17.3: T_start UT T0+ Filter, Exposure, OT, uplim (3 sigma) (mid, d) (s) 23:21:13 0.3291 R 26x180 n/d 20.75 //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 13066 SUBJECT: GRB 120312A, the review of the sky area in plate archives DATE: 12/03/15 16:45:55 GMT FROM: Valentyna Golovnya at Main Astro Obs,Kyiv V.V.Golovnya (Main Astro Obs, Kyiv) report: We have undertaken the review of the sky area in vicinity of GRB 120312A (V. Mangano et al. GCN Circ.13053) on astronegatives, collected in Ukrainian NAS Main astronomical observatory plate archive (1976-1996). All the plates with the possible object appearance are digitized using Microtek ScanMaker 9800XL TMA and Epson Expression 10000XL flatbed scanners and have been placed into Golosiiv Plate Archive database DBGPA with open access to them. The list of plates is given in the table: YYYYMMDD/TimeUT --Plates-- Exp. LimMag Star USNOA2 19810626/221142 GUA040C001973B 34.0 15.00 1125-07810808 19810626/221142 GUA040D001974 34.0 15.00 1125-07810808 19870424/003510 GUA040C001043A 18.0 16.10 1125-07808472 19870424/010141 GUA040C001044 16.0 15.00 1125-07810808 19890601/214206 GUA040C001474 18.0 16.65 1125-07808939 19900621/205220 GUA040C001663A 16.5 15.00 1125-07810808 19910615/211004 GUA040C001806A 22.5 16.10 1125-07808472 Plates: –the plates archive identifier of DWA (D/F=400/2000, GUA040C, M=103"/mm) of the Ukrainian NAS Main Astro obs. GUA040D (Marsden's number - 83) the plate number [1]. Exp. - Duration of the maximum exposure (minutes). LimM - Limited V mag, derived in the 24 minutes area around the location given in V. Mangano et al. GCN Circ.13053: RA(J2000)= 16h 47m 09.16s, Dec(J2000)= +23d 51' 29.4" Star USNOA2 - Comparison star. The preview images of 7 areas together with the 24x24 min.of arc area from SkyMap can be found in http://gua.db.ukr-vo.org/img/grb/120312A/index.html The images with full resolution are available via e-mail on demand. References: 1.L.Pakuliak DATABASE of GOLOSIIV PLATE ARCHIVE (DBGPA V2.0), http://gua.db.ukr-vo.org