//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15421 SUBJECT: GRB 131031A found in ground analysis of BAT data DATE: 13/10/31 21:10:02 GMT FROM: Jay R. Cummings at NASA/GSFC/Swift J. R. Cummings reports on behalf of the Swift science team: At 11:33:31 UT, Swift-BAT rate-triggered on GRB 131031A (trigger 576277). No significant source was found onboard. In ground analysis, a significant source was found at the very edge of the BAT field of view (3% coded). The location is RA, Dec 29.618, -1.603, which is: RA (J2000) 01h 58m 28.3s Dec (J2000) -01d 36' 11" with an estimated error radius of 4 arcmin (90% containment). This GRB also triggered Fermi GBM. The burst was about 8 seconds long, with a multipeaked structure. A Swift TOO request has been submitted to locate the afterglow with XRT and UVOT. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15422 SUBJECT: GRB 131031A: 1.23m CAHA I-band and 1.5m OSN R-band observations of Swift/BAT error circle DATE: 13/10/31 23:28:53 GMT FROM: Javier Gorosabel at IAA-CSIC V. Terron (IAA-CSIC), J. Gorosabel (IAA-CSIC,UPV/EHU), A. de Ugarte Postigo (IAA-CSIC, DARK/NBI), A.J. Castro-Tirado (IAA-CSIC), A. Sota (IAA-CSIC), report on behalf of a larger collaboration: We imaged the field of the GRB131031A (Cummings GCN 15421) with the 1.23m CAHA telescope. The observations were carried out at 21:24--22:04 UT (mean epoch 10.2 hours post burst) in the I-band with a total exposure time of 7x300s. Visual comparison with the SDSS did not reveal new objects brighter than I~20.5 (Vega) within the BAT error circle. A contemporaneous 900s R-band image taken with the 1.5m OSN telescope did not reveal any new object either brighter than R>19.5 (Vega). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15424 SUBJECT: GRB 131031A: Swift-XRT observations DATE: 13/11/01 06:36:03 GMT FROM: Kim Page at U.of Leicester B.P. Gompertz and K.L. Page (U. Leicester) report on behalf of the Swift-XRT team: We have analysed 3.7 ks of XRT data for the Swift/BAT-detected burst: GRB 131031A, from 39.7 ks to 52.0 ks after the Swift/BAT trigger. The data are entirely in Photon Counting (PC) mode. An X-ray source is detected within the Swift/BAT error circle. Using 1649 s of PC mode data and 1 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 = 29.61022, -1.57882 which is equivalent to: RA (J2000): 01h 58m 26.45s Dec(J2000): -01d 34' 43.7" with an uncertainty of 4.7 arcsec (radius, 90% confidence). This position is 91 arcsec from the Swift/BAT position. The source has a mean count rate of 8.8e-03 ct/sec; we cannot determine at the present time whether it is fading. The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00020317. This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15426 SUBJECT: GRB 131031A: 1.23m CAHA afterglow candidate DATE: 13/11/01 08:48:12 GMT FROM: Antonio de Ugarte Postigo at IAA-CSIC J. Gorosabel (IAA-CSIC,UPV/EHU), A. de Ugarte Postigo (IAA-CSIC, DARK/NBI), V. Terron (IAA-CSIC) report on behalf of a larger collaboration: Further analysis of the observations of the field of GRB 131031A (Cummings GCN 15421) obtained with the 1.23m CAHA in I-band, 10.2 hr after the burst (Terron et al. GCN 15422), reveals a source consistent with the XRT afterglow candidate at the following coordinates (J2000+/-0.5"): R.A.: 01:58:26.46 Dec: -01:34:48.1 This source is not present in the archival SDSS images and has a magnitude of i(AB)=21.63+/-0.25 as compared with SDSS field stars. Thus, we propose it as the optical afterglow of GRB 131031A. Further observations will be needed to check for variability. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15428 SUBJECT: Konus-Wind observation of GRB 131031A DATE: 13/11/01 09:21:25 GMT FROM: Dmitry Frederiks at Ioffe Institute S. Golenetskii, R.Aptekar, D. Frederiks, V. Pal'shin, P. Oleynik, M. Ulanov, D. Svinkin, and T. Cline on behalf of the Konus-Wind team, report: The long-duration GRB 131031A (Cummings, GCN 15421) triggered Konus-Wind at T0=41619.496 s UT (11:33:39.496). The burst light curve shows a multi-peaked structure from ~T0-0.5 s till ~T0+6 s. The emission is seen up to ~7 MeV. The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB131031_T41619/ As observed by Konus-Wind, the burst had a fluence of (4.8 ± 1.2)x10-6 erg/cm2, and a 64-ms peak flux, measured from T0+0.064 s, of (3.8 ± 0.5)x10-6 erg/cm2/s (both in the 20 keV - 10 MeV energy range). The time-averaged spectrum (measured from T0 to T0+8.448 s) is best fit in the 20 keV - 15 MeV range by a simple power law with the photon index 2.09 ± 0.15, chi2 = 82.5/99 dof. The spectrum at the maximum count rate (measured from T0 to T0+0.256 s) is best fit in the 20 keV - 15 MeV range by a simple power law with the photon index 1.96 ± 0.18, chi2 = 51.3/72 dof. All the quoted values are preliminary. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15429 SUBJECT: GRB 131031A: MASTER optical observation DATE: 13/11/01 10:36:33 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V.Yurkov, Yu.Sergienko, D.Varda, E.Sinyakov Blagoveschensk Educational State University, Blagoveschensk 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, A.Sankovich Sternberg Astronomical Institute, Moscow State University K.Ivanov, S.Yazev, N.M.Budnev, O.Gres, O.Chuvalaev, V.A.Poleshchuk Irkutsk State University V.Krushinski, I.Zalozhnih, A. Popov Ural Federal University, Kourovka A. Tlatov, A.V. Parhomenko, D. Dormidontov, V.Sennik Kislovodsk Solar Station of the Pulkovo Observatory 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 Blagoveschensk was pointed to the GRB131031A 11 s after notice time and 51 s after GRB time at 2013-10-31 11:34:23UT by FERMI trigger N404912015. Using very wide field cameras (FOV=2x384 square degrees, D=72mm, f/1.2, 1 pix = 22 arcsec), we cover Swirt error box (Cummings et al. GCN15421). The 5-sigma upper limit has been about 11 mag on single 5 sec image and 12.5 on coaad of 12 continuously images with total exposure 60 sec. On 40-cm MASTER-II telescope with FOV 4 sq. degree look at a center of FERMI GBM error box (ra=01 47 16 dec=+00 33 34 r=2.3) and not cover Swirt error box . The message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15433 SUBJECT: GRB 131031A: Swift/UVOT Upper Limits DATE: 13/11/01 13:47:39 GMT FROM: Paul Kuin at MSSL Paul Kuin (UCL/MSSL) and Eleonora Troja (GSFC) report on behalf of the Swift/UVOT team: The Swift/UVOT began observations of the field of GRB 131031A 39.7ks after the ground-detected BAT trigger (Cummings, GCN Circ. 15421). An otical afterglow candidate was reported by Gorosabel et al. (GCN Circ. 15426) but no optical afterglow consistent with the XRT position (Gompertz et al., GCN Circ. 15423) 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 exposures are: Filter T_start(s) T_stop(s) Exp(s) Mag white 40274 52042 1559 >21.1 v 40825 47155 762 >20.1 u 39724 51207 1559 >21.1 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.03 in the direction of the burst (Schlegel et al. 1998). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15434 SUBJECT: GRB 131031A: Fermi GBM detection DATE: 13/11/01 16:11:16 GMT FROM: Narayana Bhat at U Alabama/Huntsville/GBM G. Fitzpatrick (UCD) and P. N. Bhat (UAH) report on behalf of the Fermi GBM Team: At 11:33:32.82 UT on 31 October 2013, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 131031A (trigger 404912015/131031482). This GRB was also detected by Swift in ground analysis (Cummings, GCN 15421) and by Konus-Wind (Golenetskii et al., GCN 15428). The angle from the Fermi LAT boresight is 46 degrees. The on-ground calculated location is consistent with the Swift location. The GBM light curve is multi-peaked with a duration (T90) of about 7.4 s (50-300 keV). The time-averaged spectrum from T0+0.003 s to T0+7.424 s is adequately fit by a Band function with Epeak = 92.1 +/- 7.0 keV, alpha = -0.8 +/- 0.1 , and beta = -2.3 +/- 0.1. The event fluence (10-1000 keV) in this time interval is (4.3 +/- 0.1)E-06 erg/cm^2. The 1-sec peak photon flux measured starting from T0+0.6 s in the 10-1000 keV band is 10.2 +/- 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: 15438 SUBJECT: GRB131031A: RATIR Optical and NIR Observations DATE: 13/11/02 00:56:18 GMT FROM: Antonino Cucchiara at UCSC/UCO Lick A. 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 131031A (Cummings et al., GCN 15421) 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 2013/11 1.21 to 2013/11 1.48 UTC (17.44 to 23.99 hours after the BAT trigger), obtaining a total of 4.47 hours exposure in the r and i bands and 1.81 hours exposure in the Z, Y, J, and H bands. The source within the XRT error circle (Gompertz et al., GCN 15424) and confirmed by Gorosabel et al. (GCN 15426) is clearly detected. In comparison with the SDSS DR9 and 2MASS, we obtain the following detections and upper limits (3-sigma): r 22.38 +/- 0.07 i 22.34 +/- 0.09 Z 21.89 +/- 0.14 Y > 21.81 J > 21.36 H > 20.69 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: 15439 SUBJECT: GRB 131031A: RATIR Optical and NIR Observations and Upper Limits DATE: 13/11/02 22:01:34 GMT FROM: Owen Littlejohns at Az State U Owen Littlejohns (ASU), 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), Antonino Cucchiara (ORAU/GSFC), Eleonora Troja (GSFC), 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 again observed the field of GRB 131031A (Cummings et al., GCN 15421) 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 2013/11 2.09 to 2013/11 2.49 UTC (38.53 to 48.15 hours after the BAT trigger), obtaining a total of 6.23 hours exposure in the r and i bands and 2.50 hours exposure in the Z, Y, J, and H bands. The source detected in the first epoch of RATIR observations (Cucchiara et al., GCN 15438) within the Swift-XRT error circle (Gompertz et al., GCN 15424) and confirmed by Gorosabel et al. (GCN 15426) has faded. In comparison with 2MASS, we obtain the following detections and upper limits (3-sigma): r 22.98 +/- 0.11 i > 22.36 Z > 21.85 Y > 21.78 J > 21.62 H > 21.19 These magnitudes are in the AB system and are not corrected for Galactic extinction in the direction of the GRB. In comparison to the first epoch of RATIR observations (Cucchiara et al., GCN 15438), the source has faded by 0.6 magnitudes in the r band. This is consistent with a power-law decay of approximately t^-0.75. We thank the staff of the Observatorio Astronómico Nacional in San Pedro Mártir. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15461 SUBJECT: GRB 131031A: Swift-XRT afterglow confirmation DATE: 13/11/06 15:13:36 GMT FROM: Phil Evans at U of Leicester P.A. Evans & B.P. Gompertz (U. Leicester) report on behalf of the Swift-XRT team: Swift-XRT performed a second observation of GRB 131031A (Cummings, GCN 15421) on 2013 Nov 5, for 4.7 ks. The XRT source reported by Gompertz & Page (GCN 15424) is undetected, with a 3-sigma upper limit of 2.5e-3 ct/sec, well below the level of the previous detection. We therefore conclude that this was the afterglow of GRB 131031A. This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15486 SUBJECT: GRB 131031A: Mondy optical observations DATE: 13/11/15 00:06:28 GMT FROM: Alina Volnova at SAI MSU A. Volnova (IKI), E. Klunko (ISTP), M. Eselevich (ISTP), I. Korobtsev (ISTP), A. Pozanenko (IKI) report on behalf of larger GRB follow-up collaboration: We observed the field of the Swift GRB 131031A (Cummings et al., GCN 15421) with AZT-33IK telescope of Sayan observatory (Mondy). We took several images in R-filter of 60 s exposure on Nov., 01, 02, and 05. In the stacked images from Nov. 01 and 02 in the XRT error circle (Gompertz & Page, GCN 15424) we detected a source which is coincident with the source reported by Gorosabel et al. (GCN 15426). The details of the photometry are the following: date UT start t-T0 Filter Exp. OT (mid, days) (s) 20131101 15:50:21 1.23918 R 147x60 22.23 +/- 0.14 20131102 14:59:29 2.17988 R 106x60 22.43 +/- 0.16 20131105 15:59:53 5.21974 R 91x60 >22.3 (UL 3 sigma) The photometry is based 3 SDSS stars, R (gri -> R transformations by Lupton 2005): SDSS id R J015828.04-013339.6 19.230 J015828.59-013429.3 17.299 J015835.16-013313.8 18.742