//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 13004 SUBJECT: GRB 120305A: Swift detection of a short burst DATE: 12/03/05 20:03:38 GMT FROM: Scott Barthelmy at NASA/GSFC G. Stratta (ASDC), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), D. N. Burrows (PSU), J. R. Cummings (NASA/UMBC), N. Gehrels (NASA/GSFC), B. Gendre (ASDC), C. Guidorzi (U Ferrara), S. T. Holland (STScI), J. A. Kennea (PSU), H. A. Krimm (CRESST/GSFC/USRA), A. Y. Lien (NASA/GSFC/ORAU), V. Mangano (INAF-IASFPA), C. B. Markwardt (NASA/GSFC), F. E. Marshall (NASA/GSFC), A. Melandri (INAF-OAB), T. Sakamoto (NASA/UMBC), C. J. Saxton (UCL-MSSL), B. Sbarufatti (INAF-OAB/PSU), C. A. Swenson (PSU), G. Tagliaferri (INAF-OAB), E. Troja (NASA/GSFC/ORAU) and B.-B. Zhang (PSU) report on behalf of the Swift Team: At 19:37:30 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 120305A (trigger=516997). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 47.546, +28.493 which is RA(J2000) = 03h 10m 11s Dec(J2000) = +28d 29' 36" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve shows a single spike with a duration of about 200 msec. The peak count rate was ~32000 counts/sec (15-350 keV), at ~0 sec after the trigger. Using promptly downlinked data we find a bright, fading, uncatalogued X-ray source with an enhanced position: RA, Dec 47.5368, 28.4915 which is equivalent to: RA(J2000) = 03h 10m 08.84s Dec(J2000) = +28d 29' 29.3" with an uncertainty of 2.6 arcseconds (radius, 90% containment). This location is 29 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 (1.13 x 10^21 cm^-2, Kalberla et al. 2005), with an excess column of 4 (+3.38/-2.63) x 10^21 cm^-2 (90% confidence). The initial flux in the 2.5 s image was 1.03e-09 erg cm^-2 s^-1 (0.2-10 keV). UVOT took a finding chart exposure of 150 seconds with the White filter starting 71 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 0.43. We note quasi-periodic variability in the BAT lightcurve before and after the burst. We believe it is unrelated to the GRB and could be coming from a different source, but will further examine the data to determine the origin. Burst Advocate for this burst is G. Stratta (giulia.stratta AT asdc.asi.it). 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: 13005 SUBJECT: GRB 120305A: MASTER-NET early optical observations DATE: 12/03/05 20:39:03 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs 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 A. Tlatov, A.V. Parhomenko, D. Dormidontov, V.Sennik Kislovodsk Solar Station of the Pulkovo Observatory V.Yurkov, Yu.Sergienko, D.Varda, E.Sinyakov Blagoveschensk Educational State University, Blagoveschensk K.Ivanov, S.Yazev, N.M.Budnev, O.Gres, O.Chuvalaev, V.A.Poleshchuk Irkutsk State University 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 Kislovodsk was pointed to the short GRB120305A 32 sec after notice time and 57 sec after GRB time at 2012-03-05 19:38:26.385 UT in two polarizations. On our first (10s exposure) set we haven`t found optical transient within SWIFT error-box (ra=03 10 11 dec=+28 29 21 r=0.050000). The 5-sigma upper limit has been about 16.0 mag. The message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 13006 SUBJECT: GRB 120305A - Liverpool Telescope Observations DATE: 12/03/05 21:43:15 GMT FROM: Francisco Virgili at Liverpool John Moores U F. J. Virgili (Liverpool, JMU), C. Guidorzi (U. Ferrara), A. Melandri (INAF-OAB), C.G. Mundell (Liverpool, JMU) report: "The 2-m Liverpool Telescope robotically followed up GRB 120305A (SWIFT trigger 516997; Stratta et al., GCN Circ 13004) 14.00 min after the GRB trigger time. No optical counterpart is detected within the XRT error circle to the following conservative limits: r' > 21.3 mag (vs USNOB1) i' > 21.0 mag (vs USNOB1). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 13007 SUBJECT: GRB 120305A: Swift-BAT refined analysis DATE: 12/03/06 00:10:00 GMT FROM: Scott Barthelmy at NASA/GSFC D. M. Palmer (LANL), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC), T. Sakamoto (GSFC/UMBC), M. Stamatikos (OSU), G. Stratta (ASDC), J. Tueller (GSFC), T. N. Ukwatta (MSU) (i.e. the Swift-BAT team): Using the data set from T-60 to T+243 sec from recent telemetry downlinks, we report further analysis of BAT GRB 120305A (trigger #516997) (Stratta, et al., GCN Circ. 13004). The BAT ground-calculated position is RA, Dec = 47.549, 28.495 deg which is RA(J2000) = 03h 10m 11.8s Dec(J2000) = +28d 29' 41.2" with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment). The partial coding was 92%. The mask-weighted light curve shows a single FRED-like spike starting at ~T+0.00 sec, peaking at ~T+0.02 sec, and returning to baseline at ~T+0.20 sec. At the ~2-sigma level, there is possible emission out to ~T+20 sec. T90 (15-350 keV) is 0.10 +- 0.02 sec (estimated error including systematics). The time-averaged spectrum from T+0.00 to T+0.136 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.00 +- 0.09. The fluence in the 15-150 keV band is 2.0 +- 0.1 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T-0.43 sec in the 15-150 keV band is 2.2 +- 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/516997/BA/ //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 13008 SUBJECT: GRB 120305A: Enhanced Swift-XRT position DATE: 12/03/06 00:24:59 GMT FROM: Phil Evans at U of Leicester A.P. Beardmore, P.A. Evans, M.R. Goad and J.P. Osborne (U. Leicester) report on behalf of the Swift-XRT team. Using 448 s of XRT Photon Counting mode data and 1 UVOT images for GRB 120305A, 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 = 47.53639, +28.49191 which is equivalent to: RA (J2000): 03h 10m 8.73s Dec (J2000): +28d 29' 30.9" with an uncertainty of 2.0 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: 13009 SUBJECT: GRB 120305A: Swift-XRT refined Analysis DATE: 12/03/06 08:03:06 GMT FROM: Phil Evans at U of Leicester K.L. Page (U. Leicester), C. Pagani (U. Leicester), V. D'Elia (ASDC), A. Maselli (INAF-IASFPA), V. Mangano (INAF-IASFPA), M.C. Stroh (PSU), D.N. Burrows (PSU), J.A. Kennea (PSU), A.P. Beardmore (U. Leicester) and G. Stratta report on behalf of the Swift-XRT team: We have analysed 8.2 ks of XRT data for GRB 120305A (Stratta et al. GCN Circ. 13004), from 69 s to 24.9 ks after the BAT trigger. The data comprise 85 s in Windowed Timing (WT) mode with the remainder in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Beardmore et al. (GCN. Circ 13008). The light curve can be modelled with a power-law decay with a decay index of alpha=2.66 (+0.22, -0.19). A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 1.94 (+0.21, -0.20). The best-fitting absorption column is 4.7 (+1.1, -0.9) x 10^21 cm^-2, in excess of the Galactic value of 1.1 x 10^21 cm^-2 (Kalberla et al. 2005). The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 4.5 x 10^-11 (7.5 x 10^-11) erg cm^-2 count^-1. A summary of the WT-mode spectrum is thus: Total column: 4.7 (+1.1, -0.9) x 10^21 cm^-2 Galactic foreground: 1.1 x 10^21 cm^-2 Excess significance: 6.4 sigma Photon index: 1.94 (+0.21, -0.20) The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00516997. This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 13010 SUBJECT: GRB 120305A: EVLA deep limit on a radio counterpart DATE: 12/03/06 15:38:02 GMT FROM: Wen-fai Fong at CFA B. A. Zauderer, W. Fong and E. Berger (Harvard) report: "We observed the location of the short-duration GRB 120305A (GCN 13004) with the EVLA starting on 2012 March 05.98 UT (3.9 hours post-burst). We obtained two hours of observations at a mean frequency of 5.8 GHz. We do not detect any radio source within the latest enhanced XRT position (improved from GCN 13008 with RA = 03:10:08.76, Dec = +28:29:30.2 (J2000), 1.9" uncertainty; http://www.swift.ac.uk/xrt_positions/00516997/) to a 3-sigma limit of ~18 microJy." //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 13011 SUBJECT: GRB 120305A: Swift/UVOT Upper Limits DATE: 12/03/06 17:55:47 GMT FROM: Frank Marshall at GSFC F. E. Marshall (NASA/GSFC) and G. Stratta (ASDC) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 120305A 72 s after the BAT trigger (Stratta et al., GCN Circ. 13004). No optical afterglow consistent with the enhanced XRT position (Beardmore et al., GCN Circular 13008) 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 finding chart (FC) exposures and subsequent exposures are: Filter T_start(s) T_stop(s) Exp(s) Mag white (FC) 72 221 147 >20.1 u (FC) 284 534 246 >20.4 white 72 6382 363 >21.1 v 5158 11729 1082 >19.7 b 540 18740 428 >20.4 u 284 24898 1918 >21.2 w1 5567 24288 1968 >20.7 m2 11734 23381 1740 >21.0 w2 6388 6584 193 >20.4 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.43 in the direction of the burst (Schlegel et al. 1998). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 13015 SUBJECT: GRB 120305A: Swift spectral lag analysis DATE: 12/03/07 13:15:04 GMT FROM: Scott Barthelmy at NASA/GSFC J. Norris (BSU), S.D. Barthelmy (GSFC) for the BAT Team: We report the spectral lag analysis for GRB 120305A (GCN Circ. 13004) based on the BAT data. Using 1-ms binned light curves, the spectral lag for the 15-25 keV to 50-100 keV bands is 2.0 +0.6/-0.9 msec, and -2.6 +0.6/-0.4 msec for the 25-50 keV to 100-350 keV bands for both peaks combined. These lag values place this burst in the short burst category. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 13016 SUBJECT: GRB 120305A: D50 optical limits DATE: 12/03/07 15:37:04 GMT FROM: Jan Strobl at AI AS CR,Ondrejov Jan Strobl (1), Martin Jelinek (2), Cyril Polasek (1), Martin Nekola (1), Martin Blazek (1), Petr Kubanek (3) and Rene Hudec (1) (1. ASU AVCR Ondrejov, 2. IAA-CSIC Granada, 3. FZU AVCR) We observed the field of Swift GRB 120305A (Stratta et al., GCNC 13004) with the 0.5m telescope D50 in Ondrejov (Czech Republic), starting at 19:39:12.6UT i.e. 102.6s after the trigger. A sequence of 20s unfiltered images was obtained. We do not detect any new source in individual (limit Rc~17.5) nor coadded images (limit Rc~19.2). This message can be cited.