//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15371 SUBJECT: GRB 131024B: Swift detection of a burst DATE: 13/10/24 21:56:41 GMT FROM: Hans Krimm at NASA-GSFC H. A. Krimm (CRESST/GSFC/USRA), M. M. Chester (PSU), S. T. Holland (STScI), J. A. Kennea (PSU), V. Mangano (PSU), C. B. Markwardt (NASA/GSFC), F. E. Marshall (NASA/GSFC), A. Maselli (INAF-IASFPA), J. L. Racusin (NASA/GSFC), B. Sbarufatti (INAF-OAB/PSU), C. A. Swenson (PSU), E. Troja (NASA/GSFC/UMCP) and B.-B. Zhang (UAH) report on behalf of the Swift Team: At 21:35:31 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 131024B (trigger=575754). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 144.403, +44.240 which is RA(J2000) = 09h 37m 37s Dec(J2000) = +44d 14' 23" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a multiple-peak structure with a duration of about 30 sec. The peak count rate was ~1000 counts/sec (15-350 keV), at ~2 sec after the trigger. The XRT began observing the field at 21:37:21.8 UT, 110.5 seconds after the BAT trigger. Using promptly downlinked data we find a bright, fading, uncatalogued X-ray source with an enhanced position: RA, Dec 144.5032, 44.2715 which is equivalent to: RA(J2000) = 09h 38m 00.76s Dec(J2000) = +44d 16' 17.6" with an uncertainty of 2.1 arcseconds (radius, 90% containment). This location is 282 arcseconds from the BAT onboard position. 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 (1.27 x 10^20 cm^-2, Kalberla et al. 2005), with an excess column of 2.6 (+1.51/-1.36) x 10^21 cm^-2 (90% confidence). The initial flux in the 2.5 s image was 5.91e-10 erg cm^-2 s^-1 (0.2-10 keV). UVOT took a finding chart exposure of 250 seconds with the U filter starting 278 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 19.2 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 18.0 mag. No correction has been made for the expected extinction corresponding to E(B-V) of 0.02. Burst Advocate for this burst is H. A. Krimm (krimm 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.) [GCN OPS NOTE(24oct13): The Admin changed the burst name from an "A" to a "B" in the first sentence.] //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15374 SUBJECT: GRB 131024B: Enhanced Swift-XRT position DATE: 13/10/25 03:20:30 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 1402 s of XRT Photon Counting mode data and 2 UVOT images for GRB 131024B, 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 = 144.50331, +44.27151 which is equivalent to: RA (J2000): 09h 38m 0.79s Dec (J2000): +44d 16' 17.4" with an uncertainty of 2.8 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: 15376 SUBJECT: GRB 131024B: Nanshan optical upper limit DATE: 13/10/25 03:26:23 GMT FROM: Dong Xu at DARK/NBI D. Xu (DARK/NBI), X. Zhang, C-H. Bai, A. Esamdin, L. Ma (XAO) report: We observed the field of GRB 131024B (Krimm et al., GCN 15371) using the 1m telescope located on Mt. Nanshan, Xinjiang, China. We obtained 4x300s R-band frames at a mean time of 2013-10-24 23:21:53 UT, i.e., 1.773 hr after the BAT trigger. No optical source is detected within the XRT error circle in the stacked image down to a limiting magnitude of R=21.0, calibrated with nearby SDSS field. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15378 SUBJECT: GRB 131024B: Swift-XRT refined Analysis DATE: 13/10/25 13:31:33 GMT FROM: Alessandro Maselli at INAF/IASF Palermo H. A. Krimm (CRESST/GSFC/USRA), A. Maselli (INAF-IASFPA) and P. A. Evans (U. Leicester) report on behalf of the Swift-XRT team: We have analysed 5.5 ks of XRT data for GRB 131024B (Krimm et al. GCN Circ. 15371), from 100 s to 29.1 ks after the BAT trigger. The data comprise 185 s in Windowed Timing (WT) mode (the first 8 s were taken while Swift was slewing) with the remainder in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Beardmore et al. (GCN. Circ 15374). The light curve can be modelled with a series of power-law decays. The initial decay index is alpha=1.30 (+0.22, -0.47). At T+232 s the decay steepens to an alpha of 3.4 (+2.8, -1.0) before breaking again at T+328 s to a final decay with index alpha=1.72 (+0.13, -0.11). A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 1.60 (+/-0.14). The best-fitting absorption column is 1.9 (+0.5, -0.4) x 10^21 cm^-2, in excess of the Galactic value of 1.3 x 10^20 cm^-2 (Kalberla et al. 2005). The PC mode spectrum has a photon index of 1.79 (+0.25, -0.23) and a best-fitting absorption column of 1.0 (+/-0.6) x 10^21 cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 4.1 x 10^-11 (5.0 x 10^-11) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Total column: 1.0 (+/-0.6) x 10^21 cm^-2 Galactic foreground: 1.3 x 10^20 cm^-2 Excess significance: 2.6 sigma Photon index: 1.79 (+0.25, -0.23) If the light curve continues to decay with a power-law decay index of 1.72, the count rate at T+24 hours will be 1.2 x 10^-4 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 5.0 x 10^-15 (6.0 x 10^-15) erg cm^-2 s^-1. The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00575754. This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15379 SUBJECT: GRB 131024B : Xinglong TNT upper limit DATE: 13/10/25 13:48:56 GMT FROM: L.P. Xin at NAOC L. P. Xin, J. Y. Wei, Y. L. Qiu, J. S. Deng, J. Wang, X. H. Han and C. Wu on behalf of EAFON report: We began to observe GRB 131024B (Krimm et al., GCN 15371) with Xinglong 0.8-m TNT telescope at 21:38:56 (UT), about 3.4 min after the burst. 3*300 sec R-band images were obtained. No any optical counterpart within the XRT error circle was detected down to a limit of 18.4 mag in R band, calibrated by USNO B1.0 R2mag at the mean time of 11.25 min after the burst. This message may be cited.//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15380 SUBJECT: GRB 131024B: Swift/UVOT Upper Limits DATE: 13/10/25 14:20:06 GMT FROM: Margaret Chester at PSU M. M. Chester (PSU) and H. A. Krimm (CRESST/GSFC/USRA) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 131024B 121 s after the BAT trigger (Krimm et al., GCN Circ. 15371). No optical afterglow consistent with the XRT position (Beardmore et al. GCN Circ. 15374) 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 second finding chart (FC) exposure and subsequent exposures are given in the following table. (The first finding chart in White was incomplete and is not included in the analysis.) Filter T_start(s) T_stop(s) Exp(s) Mag u_FC 278 528 246 >19.7 white 559 5579 413 >21.8 v 609 5990 413 >20.6 b 535 5374 228 >20.5 u 278 6484 539 >20.3 w1 658 6401 413 >20.4 m2 4558 6195 393 >20.9 w2 585 5785 413 >21.3 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.02 in the direction of the burst (Schlegel et al. 1998). ************************************************************************ Dr. Margaret Chester Swift Deputy Mission Director U.S. Mail: The Pennsylvania State University Swift Explorer Program Department of Astronomy & Astrophysics 2582 Gateway Drive Office: (814) 865-7746 State College, PA 16801 Cell: (814) 359-9026 FAX: (814) 865-9100 //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15381 SUBJECT: GRB 131024B: RATIR Optical and NIR Observations DATE: 13/10/25 15:45:15 GMT FROM: Antonino Cucchiara at UCSC/UCO Lick Antonino Cucchiara (ORAU/GSFC), Nat Butler (ASU), Alan M. Watson (UNAM), Alexander Kutyrev (GSFC), William H. Lee (UNAM), Michael G. Richer (UNAM), Chris Klein (UCB), Ori Fox (UCB), J. Xavier Prochaska (UCSC), Josh Bloom (UCB), Eleonora Troja (GSFC), Owen Littlejohns (ASU), Enrico Ramirez-Ruiz (UCSC), José A. de Diego (UNAM), Leonid Georgiev (UNAM), Jesús González (UNAM), Carlos Román-Zúñiga (UNAM), Neil Gehrels (GSFC), and Harvey Moseley (GSFC) report: We observed the field of GRB 131024B (Krimm, et al., GCN 15371) with the Reionization and Transients Infrared Camera (RATIR; www.ratir.org) on the 1.5m Harold Johnson Telescope at the Observatorio Astronómico Nacional on Sierra San Pedro Mártir from 2013/10 25.41 to 2013/10 25.52 UTC (12.28 to 14.87 hours after the BAT trigger), obtaining a total of 1.78 hours exposure in the r and i bands and 0.74 hours exposure in the Z, Y, J, and H bands. For a source within the Swift-XRT error circle, in comparison with the SDSS DR9 and 2MASS, we obtain the following upper limits (3-sigma): r > 23.68 i > 23.35 Z > 22.44 Y > 22.01 J > 21.75 H > 21.49 These magnitudes are in the AB system and are not corrected for Galactic extinction in the direction of the GRB. We thank the staff of the Observatorio Astronómico Nacional in San Pedro Mártir.//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15382 SUBJECT: GRB 131024B: Fermi GBM observation DATE: 13/10/25 16:48:55 GMT FROM: Binbin Zhang at UAH Bin-Bin Zhang (UAH) reports on behalf of the Fermi GBM Team: "At 21:35:28.85 UT on October 24 2013, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 131024B (trigger 404343331/131024900), which was also detected by Swift (Krimm et al., GCN 15371). The GBM on-ground location is consistent with the Swift/XRT position (Beardmore et al., GCN 15374). The angle from the Fermi LAT boresight is 83 degrees. The GBM light curve consists of a multiple-peak structure with a duration of about 52 s (50-300 keV). The time-averaged spectrum from T0+0 s to T0+41 s is well best fit with a power law function with an exponential high-energy cutoff parameterized as Epeak = 1047 +/- 627 keV and an Index = -1.01 +/- 0.12. The event fluence (10-1000 keV) in this time interval is (6.35 +/- 0.61)E-06 erg/cm^2. The 1.0-sec peak photon flux measured starting from T0+1 s in the 10-1000 keV band is 1.48 +/- 0.2 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog." //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15383 SUBJECT: GRB 131024B, Swift-BAT refined analysis DATE: 13/10/25 19:01:28 GMT FROM: Hans Krimm at NASA-GSFC W. H. Baumgartner (GSFC/UMBC), S. D. Barthelmy (GSFC), J. R. Cummings (GSFC/UMBC), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), A. Y. Lien (NASA/GSFC/ORAU), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU), M. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (MSU) (i.e. the Swift-BAT team): Using the data set from T-61 to T+242 sec from the recent telemetry downlink, we report further analysis of BAT GRB 131024B (trigger #575754) (Krimm, et al., GCN Circ. 15371). The BAT ground-calculated position is RA, Dec = 144.464, 44.284 deg which is RA(J2000) = 09h 37m 51.3s Dec(J2000) = +44d 17' 02.1" with an uncertainty of 2.1 arcmin, (radius, sys+stat, 90% containment). The partial coding was 40%. The mask-weighted light curve shows activity starting around T-10 sec and continuing to ~T+100 sec. There are several weak peak superimposed. T90 (15-350 keV) is 64.00 +- 22 sec (estimated error including systematics). The time-averaged spectrum from T-12.59 to T+51.41 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 0.85 +- 0.23. The fluence in the 15-150 keV band is 1.2 +- 0.2 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+10.91 sec in the 15-150 keV band is 0.1 +- 0.1 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/575754/BA/ //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15390 SUBJECT: GRB 131024B: MASTER prompt optical observation DATE: 13/10/27 11:38:44 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs E. Gorbovskoy, V. Lipunov, D. Denisenko, V. Kornilov, A. Kuznetsov, D. Kuvshinov, N. Tyurina, N. Shatskiy, P. Balanutsa, D. Zimnukhov, V.V. Chazov Lomonosov Moscow State University, Sternberg Astronomical Institute A. Tlatov, A.V. Parhomenko, D. Dormidontov, V. Sennik Kislovodsk Solar Station of the Pulkovo Observatory K. Ivanov, S. Yazev, N.M. Budnev, O. Gres, O. Chuvalaev, V.A. Poleshchuk Irkutsk State University V. Yurkov, Yu. Sergienko, D. Varda, E. Sinyakov Blagoveschensk Educational State University, Blagoveschensk V. Krushinski, I. Zalozhnich, A. Popov, A. Bourdanov Ural Federal University H. Levato and C. Saffe Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE) C. Mallamaci, C. Lopez and F. Podest Observatorio Astronomico Felix Aguilar (OAFA) MASTER II robotic telescope (MASTER-Net: http://observ.pereplet.ru) located in Kislovodsk was pointed to the GRB131024B 27 sec s after notice time and 36 sec after GRB time at 2013-10-24T21-36-07.864 UT. On our first (10s exposure) set we haven`t found optical transient within SWIFT error-box (Krimm et. al GCN15371). The 5-sigma upper limit has been about 17.2 mag. This is the prompt observations becaus GRB duration time T_90 = 64+-22 sec (Baumgartner et al., GCN Baumgartner). Such long circular delay was due to with daily power cut on observatory. The message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15391 SUBJECT: GRB 131024B: Mondy optical upper limits DATE: 13/10/28 15:45:00 GMT FROM: Alexei Pozanenko at IKI, Moscow A.Volnova (IKI), E. Klunko (ISTP), M. Eselevich(ISTP), A. Pozanenko(IKI) report on behalf of larger GRB follow-up collaboration: We observed the field of the Swift GRB 131024B (Krimm et al., GCN 15371) with AZT-33IK telescope of Sayan observatory (Mondy) starting Oct., 24 (UT) 21:49:49, i.e. in ~14 minutes after the burst trigger. We obtained several images in R-filter with exposure of 30 and 60 seconds. Within the enhanced XRT circle (Beardmore et al., GCN 15374) we did not detect any optical counterpart. The details of the photometry are the following: UT start, t-T0 Filter Exp. OT UL (3 sigma) (mid, days) (s) 21:49:49 0.02074 R 1860 n/d 21.8 21:49:49 0.03325 R 4020 n/d 22.5 The photometry is based 3 SDSS stars, R (gri -> R transformations by Lupton 2005): SDSS id R J093757.56+441843.7 15.803 J093748.35+441919.6 17.774 J093744.86+441756.7 15.530 //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15392 SUBJECT: GRB 131024B: AAO optical upper limit DATE: 13/10/28 15:55:03 GMT FROM: Alexei Pozanenko at IKI, Moscow A. Volnova (IKI), R. Inasaridze (AAO), G. Inasaridze (AAO), V. Zhuzhunadze (AAO), Yu. Krugly (IA KhNU), I. Molotov (KIAM), A. Pozanenko (IKI) report on behalf of larger GRB follow-up collaboration: We observed the field of Swift GRB 131024B (Krimm et al., GCN 15371) with AS-32 telescope of Abastumani Observatory starting Oct., 25 (UT) 00:26:12. We obtained several unfiltered images with exposures of 120 s. On stacked images within the enhanced XRT circle (Beardmore et al., GCN 15374) we did not detect any optical counterpart. The details of the photometry are the following: UT start t-T0 Filter Exp. OT UL (3 sigma) (mid, days) (s) 00:26:12 0.16094 None 46x120 n/d 22.6 The photometry is based 3 SDSS stars, R (gri -> R transformations by Lupton 2005): SDSS id R J093757.56+441843.7 15.803 J093748.35+441919.6 17.774 J093744.86+441756.7 15.530 //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15453 SUBJECT: GRB 131024B: Suzaku WAM observation of the prompt emission DATE: 13/11/05 11:35:06 GMT FROM: Makoto Tashiro at Saitama U/Swift Y. Ishida, M. Tashiro, Y. Terada, T. Yasuda, H. Ueno, S. Sugimoto (Saitama U.), M. Ohno, K. Takaki, T. Kawano, R. Nakamura, S. Furui, Y. Fukazawa (Hiroshima U.), M. Yamauchi, N. Ohmori, M. Akiyama (Univ. of Miyazaki), K. Yamaoka (Nagoya U.), S. Sugita (Ehime U.), Y. E. Nakagawa, M. Kokubun, T. Takahashi (ISAS/JAXA), W. Iwakiri (RIKEN), Y. Hanabata (ICRR), Y. Urata (NCU), K. Nakazawa, K. Makishima (Univ. of Tokyo) on behalf of the Suzaku WAM team, report: The long GRB 131024B (Krimm et al. GCN 15371) was detected by the the Suzaku Wide-band All-sky Monitor (WAM) which covers an energy range of 50 keV - 5 MeV at 21:35:31 UT (=T0). The observed light curve shows a single peak with a duration (T90) of about 45 seconds. The fluence in 100 - 1000 keV was 4.26 (+0.84/-2.27) x 10^-6 erg/cm^2. The 1-s peak flux measured from T0+2 s was 0.73 (+0.26/-0.55) photons/cm^2/s in the same energy range. Preliminary result shows that the time-averaged spectrum from T0-5 s to T0+5 s is well fitted by a single power-law with a photon index of 2.13 (+0.28/-0.36) (chi^2/d.o.f = 12.4/14). All the quoted errors are at statistical 90% confidence level, in which the systematic uncertainties are not included. The light curves for this burst will be available at: http://www.astro.isas.jaxa.jp/suzaku/HXD-WAM/WAM-GRB/grb/untrig/grb_table.html