//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15533 SUBJECT: GRB 131128A: Swift detection of a burst DATE: 13/11/28 15:22:39 GMT FROM: David Palmer at LANL E. Sonbas (NASA/GSFC/Adiyaman Univ.), W. H. Baumgartner (GSFC/UMBC), M. G. Bernardini (INAF-OAB), S. B. Cenko (GSFC), P. D'Avanzo (INAF-OAB), V. D'Elia (ASDC), P. A. Evans (U Leicester), N. Gehrels (NASA/GSFC), S. T. Holland (STScI), A. Y. Lien (NASA/GSFC/ORAU), D. Malesani (DARK/NBI), C. B. Markwardt (NASA/GSFC), F. E. Marshall (NASA/GSFC), A. Maselli (INAF-IASFPA), A. Melandri (INAF-OAB), P. T. O'Brien (U Leicester), K. L. Page (U Leicester), D. M. Palmer (LANL), M. H. Siegel (PSU), R. L. C. Starling (U Leicester) and E. Troja (NASA/GSFC/UMCP) report on behalf of the Swift Team: At 15:06:24 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 131128A (trigger=579683). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 355.323, +31.279 which is RA(J2000) = 23h 41m 18s Dec(J2000) = +31d 16' 45" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a single FRED peak structure with a duration of about 3 sec with a possible precursor around T-8. The peak count rate was ~3000 counts/sec (15-350 keV), at ~0 sec after the trigger. The XRT began observing the field at 15:07:51.3 UT, 86.8 seconds after the BAT trigger. Using promptly downlinked data we find a fading, uncatalogued X-ray source with an enhanced position: RA, Dec 355.3084, 31.3057 which is equivalent to: RA(J2000) = 23h 41m 14.02s Dec(J2000) = +31d 18' 20.7" with an uncertainty of 2.2 arcseconds (radius, 90% containment). This location is 106 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 consistent with the Galactic value of 5.16 x 10^20 cm^-2 (Kalberla et al. 2005). UVOT took a finding chart exposure of 150 seconds with the White filter starting 90 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 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 E. Sonbas (edasonbas AT yahoo.com). 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: 15535 SUBJECT: GRB 131128A: Nanshan afterglow candidate DATE: 13/11/28 15:49:12 GMT FROM: Dong Xu at DARK/NBI D. Xu (DARK/NBI), H.-B. Niu, J.-Z. Liu, G.-J. Feng, C.-H. Bai, A. Esamdin, L. Ma (XAO) report: We observed the fields of GRB 131128A (Sonbas et al., GCN 15533), using the 1m telescope located on Mt. Nanshan, Xinjiang, China. Observations started 880s after the Swift trigger and a series of R-band frames were obtained. An optical source is clearly detected at coordinates: R.A. (J2000) = 23:41:13.75 Dec.(J2000) = +31:18:23.14 Error Radius: ~1 arcsec which is consistent with the SPER XRT position of this burst (http://www.swift.ac.uk/sper/), thus it's likely the afterglow of the GRB. Note that there is a very bright star (r=14.76 mag from SDSS) just a few arcsec away from this optical transient. Observations are ongoing. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15536 SUBJECT: GRB 131128A: MASTER-Net optical observations DATE: 13/11/28 16:59:35 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, D.Denisenko, Sternberg Astronomical Institute, Moscow State University 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 A. Tlatov, A.V. Parhomenko, D. Dormidontov, V.Sennik Kislovodsk Solar Station of the Pulkovo Observatory V.Krushinsky, I.Zalozhnih, A. Popov Ural Federal University, Yekaterinburg, Kourovka 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 GRB131128.63 12 sec after notice time and 315 sec after GRB time at 2013-11-28 15:11:39.707 UT. On our first (60s exposure) set we haven`t found optical transient within XRT SWIFT error-box. There is bright star near XRT position USNO-A2.0 1200-19996598 R_mag ~ 12. The 5-sigma upper limit has been about 17.1 mag. We do not see OT at the Nanshan afterglow candidate position (Xu et al., GCN15535). The message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15537 SUBJECT: GRB 131128A: Nanshan afterglow confirmation DATE: 13/11/28 17:21:23 GMT FROM: Dong Xu at DARK/NBI D. Xu (DARK/NBI), H.-B. Niu, J.-Z. Liu, G.-J. Feng, C.-H. Bai, A. Esamdin, L. Ma (XAO) report: Continued observations of GRB 131128A, 120s each for the beginning and 240s each for the subsequent all in R-band, at the Nanshan observatory show that the afterglow candidate in Xu et al (GCN 15535) has decayed by more than 1 magnitude at 1.95 hr after the Swift trigger, calibrated with the same nearby SDSS stars. The initial magnitude is R~19 mag in GCN 15535. We thus conclude that this object is the optical afterglow of GRB 131128A. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15538 SUBJECT: GRB 131128A: Enhanced Swift-XRT position DATE: 13/11/28 20:20:50 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 1158 s of XRT Photon Counting mode data and 2 UVOT images for GRB 131128A, 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 = 355.30781, +31.30635 which is equivalent to: RA (J2000): 23h 41m 13.88s Dec (J2000): +31d 18' 22.9" with an uncertainty of 1.8 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: 15539 SUBJECT: GRB 131128A: Swift-BAT refined analysis DATE: 13/11/28 20:51:42 GMT FROM: Scott Barthelmy at NASA/GSFC S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), A. Y. Lien (NASA/UMBC), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU), E. Sonbas (NASA/GSFC/Adiyaman Univ.), 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+962 sec from recent telemetry downlinks, we report further analysis of BAT GRB 131128A (trigger #579683) (Sonbas, et al., GCN Circ. 15533). The BAT ground-calculated position is RA, Dec = 355.305, 31.293 deg which is RA(J2000) = 23h 41m 13.3s Dec(J2000) = +31d 17' 34.1" with an uncertainty of 1.6 arcmin, (radius, sys+stat, 90% containment). The partial coding was 41%. The mask-weighted light curve shows a single symetric peak starting at ~T-2 sec, peaking at ~T+0.2 src, and ending at ~T+2.5 sec. T90 (15-350 keV) is 3.00 +- 1.41 sec (estimated error including systematics). The time-averaged spectrum from T-0.90 to T+2.10 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.81 +- 0.17. The fluence in the 15-150 keV band is 3.2 +- 0.4 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T+0.10 sec in the 15-150 keV band is 2.7 +- 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/579683/BA/ //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15540 SUBJECT: GRB 131128A: T100 observations DATE: 13/11/28 22:43:36 GMT FROM: Eda Sonbas at NASA/GSFC E. Sonbas (Adiyaman Univ.), T. Guver (Sabanci Univ.), E. Gogus (Sabanci Univ.), O. Erece (Akdeniz Univ), M. Kocak (TUG), M. Kaplan (Akdeniz Univ.) report on behalf of a larger collaboration We observed the field of Swift GRB 131128A (Sonbas et al., GCN#15533) with the 1.0 meter T100 telescope (Bakirlitepe, TUBITAK National Observatory, Turkey), starting November, 28, 17:16:02 UT (~ 2.2 hours after the trigger). 300 s $\times$ 5 exposures were obtained in the R filter under moderate weather conditions. We do not detect an optical afterglow within the reported XRT error circle down to a limiting magnitude of 21.2 in the R band. Our image is calibrated using USNO B1.0 star USNO-B1 1213-0590145 at RA :355.25992, DEC : +31.301542 (J2000). We are grateful to TUBITAK National Observatory for prompt scheduling the observations and technical support. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15541 SUBJECT: GRB 131128A: Kanata/HOWPol optical observation DATE: 13/11/29 03:01:30 GMT FROM: Koji Kawabata at HASC,Hiroshima U K. S. Kawabata, R. Itoh, N. Ebisuda, I. Ueno (Hiroshima Univ.) report on behalf of Kanata team: We performed a series of optical imaging (polarimetric mode) for the optical afterglow of GRB 131128A (Sonbas et al., GCN 15533; Xu et al., GCN 15535; Gorbovskoy et al, GCN 15536; Goad et al., GCN 15538; Sonbas et al., GCN 15540) using HOWPol attached to the 1.5-m Kanata telescope at Higashi-Hiroshima Observatory, Japan. Our first 30 sec exposure began at t=360 sec since Swift/BAT trigger and we detected the afterglow located at 9" west and 4" north of the bright star, USNO-B 2766-00858-1 (R2 = 11.63 mag). The magnitude of the afterglow is preliminarily estimated to be about R=17.5, although it might be still contaminated by the neaby bright star. The afterglow quickly decayed and became fainter than ~18 mag at t=620 sec. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15542 SUBJECT: GRB 131128A: Swift-XRT refined Analysis DATE: 13/11/29 07:22:04 GMT FROM: Phil Evans at U of Leicester P.A. Evans (U. Leicester), B.P. Gompertz (U. Leicester), A. Melandri (INAF-OAB), B. Sbarufatti (INAF-OAB/PSU), P. D'Avanzo (INAF-OAB), D.N. Burrows (PSU), J.A. Kennea (PSU), V. Mangano (PSU), J.P. Osborne (U. Leicester) and E. Sonbas report on behalf of the Swift-XRT team: We have analysed 7.6 ks of XRT data for GRB 131128A (Sonbas et al. GCN Circ. 15533), from 72 s to 40.8 ks after the BAT trigger. The data comprise 7 s in Windowed Timing (WT) mode (taken while Swift was slewing), with the remainder in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Goad et al. (GCN. Circ 15538). The light curve can be modelled with a series of power-law decays. The initial decay index is alpha=1.9 (+/-0.4). At T+423 s the decay flattens to an alpha of 0.38 (+0.08, -0.14) before breaking again at T+16.0 ks to a final decay with index alpha=1.7 (+0.7, -0.6). A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 1.53 (+0.18, -0.12). The best-fitting absorption column is 5.8 (+4.6, -0.7) x 10^20 cm^-2, consistent with the Galactic value of 5.2 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 4.6 x 10^-11 (5.0 x 10^-11) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Total column: 5.8 (+4.6, -0.7) x 10^20 cm^-2 Galactic foreground: 5.2 x 10^20 cm^-2 Excess significance: <1.6 sigma Photon index: 1.53 (+0.18, -0.12) If the light curve continues to decay with a power-law decay index of 1.7, the count rate at T+24 hours will be 3.8 x 10^-3 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.7 x 10^-13 (1.9 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/00579683. This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15544 SUBJECT: GRB 131128A: AROMA-N Optical Observation DATE: 13/11/29 11:17:17 GMT FROM: Takanori Sakamoto at AGU D. Kawamura, T. Sakamoto, I. Takahashi, S. Sugai, A. Yoshida (AGU) We observed the field of GRB 131128A detected by Swift (trigger #579683; Sonbas et al., GCN Circ. 15533) with the 12-inch AGU Robotic Optical Monitor for Astrophysical object - Narrow (AROMA-N) located at the Sagamihara campus of Aoyama Gakuin University. 60 images of 10 sec exposures were taken in the R filter starting from November 28 15:12:47 (UT) about 383 sec after the trigger (77 sec after the BAT position notice) and stopped on November 28 15:30:30 (UT). We do not detect the optical afterglow both in the individual images and the stacked image inside the enhanced XRT position (Evans, et al., GCN #15538). The estimated five sigma upper limit of the combined image (total exposure of 600 sec) is ~16.2 mag using the USNO-B1 catalog. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15545 SUBJECT: GRB 131128A: Swift/UVOT Detection DATE: 13/11/29 11:54:03 GMT FROM: Samantha Oates at MSSL S. R. Oates (UCL-MSSL) and E. Sonbas (NASA/GSFC/Adiyaman Univ.) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 131128A 91 s after the BAT trigger (Sonbas et al., GCN Circ. 15533). A source consistent with the optical position (Xu et al., GCN Circ. 15535) and the enhanced Swift-XRT position (Goad et al., GCN Circ 15538) is detected in the first UVOT white exposure only. A USNO-B1 catalogued star heavily contaminates the position of the optical candidate afterglow making the measurement very complicated. Preliminary detection and 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early exposures are: Filter T_start(s) T_stop(s) Exp(s) Mag white (FC) 91 241 147 19.11 +/- 0.11 white 583 1181 206 >21.44 u (FC) 303 552 245 >20.2 u 303 1130 285 >20.3 v 632 1231 78 >19.0 b 558 1155 58 >19.8 w1 683 1275 53 >18.9 m2 657 1255 78 >19.0 w2 608 1206 78 >19.4 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.07 in the direction of the burst //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15547 SUBJECT: GRB 131128A: GROND observations of the afterglow DATE: 13/11/29 14:41:34 GMT FROM: Sylvio Klose at TLS Tautenburg S. Schmidl, S. Klose, A. Nicuesa Guelbenzu (TLS Tautenburg), and J. Greiner (MPE Garching) report: We observed the field of GRB 131128A (Swift trigger 579683; Sonbas et al., GCN 15533) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, PASP 120, 405) mounted at the 2.2m MPG telescope at ESO La Silla Observatory (Chile). Observations started at 00:27 UT on November 29, about 9.5 hrs after the GRB trigger and were performed under moderate seeing conditions (1.6") and moderate airmass (2.3). For the optical afterglow discovered by Xu et al. (GCN 15535, 15537) we measure RA, DEC (J2000) = 23:41:13.795, +31:18:22.32 (+/- 0.2"), and r'(AB) = 22.6 +/- 0.1, calibrated against SDSS field stars (mean time 01:12 UT). Photometry in the other GROND bands is affected by a bright star very close to the afterglow. It might be improved once second-epoch data are obtained. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15554 SUBJECT: GRB 131128A; Fermi GBM observation DATE: 13/11/29 20:02:16 GMT FROM: Hoi-Fung Yu at MPE Subject: GRB 131128A: Fermi GBM observation Hoi-Fung Yu (MPE) reports on behalf of the Fermi GBM Team: "At 15:06:25.28 UT on 28 November 2013, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 131128A (trigger 407343988 / 131128629), which was also detected by the Swift/BAT (Sonbas et al., GCN 15533). This burst, tentatively classified as a particle event by the FSW onboard, is in fact a gamma-ray burst. The GBM on-ground location is consistent with the Swift/XRT position. The angle from the Fermi LAT boresight is 71 degrees. The GBM light curve consists of a single pulse with a duration (T90) of ~2.0 s (50-300 keV). The time-averaged spectrum from T0-1.024 s to T0+2.560 s is adequately fit by a power law function with an exponential high-energy cutoff. The power law index is -0.9 +/- 0.3 and the cutoff energy, parameterized as Epeak, is 61.0 +/- 9.0 keV. The event fluence (10-1000 keV) in this time interval is (4.4 +/- 0.5)E-07 erg/cm^2. The 1-sec peak photon flux measured starting from T0-0.83 s in the 10-1000 keV band is 3.8 +/- 0.3 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: 15556 SUBJECT: GRB 131128A: Bassano Bresciano Observatory optical upper limit DATE: 13/12/01 15:34:26 GMT FROM: Ulisse Quadri at Bassano Bresciano Obs U.Quadri, L.Strabla and R.Girelli report: We imaged the field of GRB 131128A detected by SWIFT(trigger 579683) with the robotic telescope of (IAU station 565) Bassano Bresciano Observatory, Italy (member of ISSP:Italian Supernovae Search Project) The observations started 1h 28m after the GRB trigger at the end of the twilight with our schmidt telescope D=320/400 mm F/D=3.1. Weather conditions were good. We co-added 6 series of 10 exposures of 120 sec each. We did not found any optical counterpart in the error box of the XRTcandidate (E.Sonbas et al. GCNC 15533). Start End Vlim 88min 279min 19.3 The afterglow probably results absorbed in the light of the near star USNO-B 2766-00858-1 (R2 = 11.63 mag) due to the focal lenght very short (1000mm) of our Schmidt telescope. Magnitudes were estimated with the USNO-B1 cat. and are not corrected for galactic dust extinction. The images are available at: http://www.osservatoriobassano.org/GRB.asp The message may be cited.