//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15269 SUBJECT: GRB 130929A: Swift detection of a burst DATE: 13/09/29 10:07:59 GMT FROM: Jamie A. Kennea at PSU/Swift-XRT F. E. Marshall (NASA/GSFC), J. R. Cummings (NASA/UMBC), J. A. Kennea (PSU), C. Pagani (U Leicester), K. L. Page (U Leicester), M. H. Siegel (PSU) and T. N. Ukwatta (MSU) report on behalf of the Swift Team: At 09:36:33 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 130929A (trigger=572308). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 135.069, -47.565 which is RA(J2000) = 09h 00m 17s Dec(J2000) = -47d 33' 53" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a single peak structure with a duration of about 10 sec. The peak count rate was ~3407 counts/sec (15-350 keV), at ~0 sec after the trigger. The XRT began observing the field at 09:38:14.6 UT, 101.5 seconds after the BAT trigger. Using promptly downlinked data we find an uncatalogued X-ray source with an enhanced position: RA, Dec 135.0241, -47.5605 which is equivalent to: RA(J2000) = 09h 00m 05.78s Dec(J2000) = -47d 33' 37.9" with an uncertainty of 2.1 arcseconds (radius, 90% containment). This location is 110 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 does not constrain the column density. UVOT took a finding chart exposure of 150 seconds with the White filter starting 280 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 0% of the XRT error circle. 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 large, but uncertain extinction expected. Burst Advocate for this burst is F. E. Marshall (marshall AT milkyway.gsfc.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: 15270 SUBJECT: GRB 130929A: TAROT La Silla observatory optical observations DATE: 13/09/29 11:59:55 GMT FROM: Alain Klotz at IRAP-CNRS-OMP Klotz A. (IRAP-CNRS-OMP), Gendre B. (IRAP-CNRS-OMP), Boer M., Siellez K., Dereli H., Bardho O. (UNS-CNRS-OCA), Atteia J.L. (IRAP-CNRS-OMP) report: We imaged the field of GRB 130929A detected by SWIFT (trigger 572308) with the TAROT robotic telescope (D=25cm) located at the European Southern Observatory, La Silla observatory, Chile. The observations started 38.0s after the GRB trigger (15.1s after the notice). The elevation of the field increased from 45 degrees above horizon and weather conditions were partially cloudy. 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 with a limiting magnitude of: t0+38.0s to t0+98.0s : Rlim = 13.6 The second image is 30.0s exposure in tracking mode: t0+112s to t0+142s : Rlim = 14.4 We co-added a series of exposures: t0+112s to t0+303s : Rlim = 15.1 Magnitudes were estimated with the nearby NOMAD1 stars and are not corrected for galactic dust extinction. N.B. Galactic coordinates are lon=268.1127 lat= -0.9424 and the galactic extinction in R band is about 8 magnitudes estimated from D. Schlegel et al. 1998ApJ...500..525S. This message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15271 SUBJECT: GRB 130929A: Enhanced Swift-XRT position DATE: 13/09/29 14:59:06 GMT FROM: Phil Evans at U of Leicester M.R. Goad, J.P. Osborne, A.P. Beardmore and P.A. Evans (U. Leicester) report on behalf of the Swift-XRT team. Using 2970 s of XRT Photon Counting mode data and 3 UVOT images for GRB 130929A, 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 = 135.02362, -47.56076 which is equivalent to: RA (J2000): 09h 00m 5.67s Dec (J2000): -47d 33' 38.7" with an uncertainty of 1.9 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: 15272 SUBJECT: GRB 130929A, Swift-BAT refined analysis DATE: 13/09/29 17:14:26 GMT FROM: Jay R. Cummings at NASA/GSFC/Swift D. M. Palmer (LANL), 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), A. Y. Lien (NASA/GSFC/ORAU), C. B. Markwardt (GSFC), F. E. Marshall (NASA/GSFC), T. Sakamoto (AGU), 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-70 to T+963 sec from the recent telemetry downlink, we report further analysis of BAT GRB 130929A (trigger #572308) (Marshall, et al., GCN Circ. 15269). The BAT ground-calculated position is RA, Dec = 135.028, -47.554 deg which is RA(J2000) = 09h 00m 06.7s Dec(J2000) = -47d 33' 14.6" with an uncertainty of 1.6 arcmin, (radius, sys+stat, 90% containment). The partial coding was 44%. The mask-weighted light curve shows a single FRED peak. T90 (15-350 keV) is 11.10 +- 2.98 sec (estimated error including systematics). The time-averaged spectrum from T-1.93 to T+11.50 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 2.00 +- 0.18. The fluence in the 15-150 keV band is 6.9 +- 0.8 x 10^-07 erg/cm2. The 1-sec peak photon flux measured from T+1.32 sec in the 15-150 keV band is 1.7 +- 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/572308/BA/ //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15273 SUBJECT: GRB 130929A: Swift-XRT refined Analysis DATE: 13/09/30 05:08:04 GMT FROM: Phil Evans at U of Leicester J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), C. Pagani (U. Leicester), A. Melandri (INAF-OAB), B. Sbarufatti (INAF-OAB/PSU), P. D'Avanzo (INAF-OAB), V. Mangano (PSU), M.C. Stroh (PSU), D.N. Burrows (PSU) and F.E. Marshall report on behalf of the Swift-XRT team: We have analysed 13 ks of XRT data for GRB 130929A (Marshall et al. GCN Circ. 15269), from 237 s to 45.5 ks after the BAT trigger. The data are entirely in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Goad et al. (GCN. Circ 15271). The light curve can be modelled with a power-law decay with a decay index of alpha=1.23 (+0.13, -0.10). A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 2.2 (+0.7, -0.6). The best-fitting absorption column is 3.3 (+1.3, -1.0) x 10^22 cm^-2, in excess of the Galactic value of 7.1 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 7.8 x 10^-11 (2.8 x 10^-10) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Total column: 3.3 (+1.3, -1.0) x 10^22 cm^-2 Galactic foreground: 7.1 x 10^21 cm^-2 Excess significance: 4.1 sigma Photon index: 2.2 (+0.7, -0.6) If the light curve continues to decay with a power-law decay index of 1.23, the count rate at T+24 hours will be 4.6 x 10^-4 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 3.6 x 10^-14 (1.3 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/00572308. This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15275 SUBJECT: GRB 130929A: Swift/UVOT Upper Limits DATE: 13/09/30 18:07:07 GMT FROM: Frank Marshall at GSFC F. E. Marshall (NASA/GSFC) reports on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 130929A 280 s after the BAT trigger (Marshall et al., GCN Circ. 15269). No optical afterglow consistent with the XRT position (Goad et al. GCN Circ. 15271) 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 280 430 147 >21.0 white 280 1008 334 >21.4 v 586 4628 236 >19.7 b 512 705 39 >19.0 u 487 10592 709 >20.6 w1 462 6710 255 >19.6 m2 437 6505 308 >19.7 w2 562 4423 236 >19.7 The magnitudes in the table are not corrected for the large Galactic extinction in the direction of the burst (Schlegel et al. 1998).