GRB131004A

This page lists all entries on GRB131004A in GRBweb

Summary Fermi GBM IPN Swift GCN 15303 GCN 15304 GCN 15305 GCN 15306 GCN 15307 GCN 15308 GCN 15309 GCN 15310 GCN 15311 GCN 15312 GCN 15313 GCN 15314 GCN 15315 GCN 15316 GCN 15317 GCN 15318 GCN 15319

Summary table
Variable Value Source
GRB_name_Fermi GRB131004904
T0 21:41:03 UTC GCN_circulars,Swift Det
ra 296.1129° Swift
decl -2.9584° Swift
pos_error 7.12e-05° Swift
T90 1.152 s Fermi_GBM
T90_error 0.59 s Fermi_GBM
T90_start 21:41:03.490 UTC Fermi_GBM
fluence 5.10e-07 erg/cm² Fermi_GBM
fluence_error 1.91e-08 erg/cm² Fermi_GBM
redshift 0.7170 GCN_circulars,Optical
T100 1.642 s
GBM_located False
mjd 56569.90350694444 GCN_circulars,Swift Det
Fermi GBM table
GRB_name_Fermi GRB131004904
trigger_name bn131004904
ra 296.1150°
decl -2.9600°
pos_error 9.55e+00°
datum 2013-10-04
t_trigger 21:41:03.682 UTC
T90 1.152 s
T90_error 0.59 s
T90_start 21:41:03.490 UTC
fluence 5.10e-07 erg/cm²
fluence_error 1.91e-08 erg/cm²
flux_1024 6.77e+00 erg/cm²/s
flux_1024_error 2.93e-01 erg/cm²/s
flux_1024_time -1.92e-01 erg/cm²/s
flux_64 9.82e+00 erg/cm²/s
flux_64_error 1.71e+00 erg/cm²/s
IPN table
GRB_name GRB131004A
ra 296.1500°
decl -2.9667°
pos_error 5.00e-02°
redshift 0.7170
Swift table
GRB_name GRB131004A
t_trigger 21:41:03 UTC
ra 296.1129°
decl -2.9584°
pos_error 7.12e-05°
T90 1.54 s
fluence 2.80e-07 erg/cm²
redshift 0.7170
GCN 15303 table
GRB_name GRB131004A
GCN_number 15303
Detection_method Swift Det
t_trigger 21:41:03 UTC
ra 296.1510°
decl -2.9600°
Circular_text TITLE: GCN CIRCULAR NUMBER: 15303 SUBJECT: GRB 131004A: Swift detection of a burst (may be short) DATE: 13/10/04 21:53:57 GMT FROM: David Palmer at LANL L. M. Z. Hagen (PSU), D. N. Burrows (PSU), V. D'Elia (ASDC), N. Gehrels (NASA/GSFC), J. A. Kennea (PSU), V. Mangano (PSU), F. E. Marshall (NASA/GSFC) and B. Sbarufatti (INAF-OAB/PSU) report on behalf of the Swift Team: At 21:41:03 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 131004A (trigger=573190). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 296.151, -2.960 which is RA(J2000) = 19h 44m 36s Dec(J2000) = -02d 57' 35" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a single-peaked structure with a duration of about 2 sec. The peak count rate was ~8500 counts/sec (15-350 keV), at ~0 sec after the trigger. The XRT began observing the field at 21:42:13.4 UT, 70.0 seconds after the BAT trigger. Using promptly downlinked data we find an uncatalogued X-ray source located at RA, Dec 296.11549, -2.95806 which is equivalent to: RA(J2000) = 19h 44m 27.72s Dec(J2000) = -02d 57' 29.0" with an uncertainty of 3.6 arcseconds (radius, 90% containment). This location is 127 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 (6.97 x 10^20 cm^-2, Kalberla et al. 2005), with an excess column of 4.5 (+2.61/-2.22) x 10^21 cm^-2 (90% confidence). UVOT took a finding chart exposure of 150 seconds with the White filter starting 75 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 BAT 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 0.28. Burst Advocate for this burst is L. M. Z. Hagen (lea.zernow.hagen AT gmail.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.)
GCN 15304 table
GRB_name GRB131004A
GCN_number 15304
Detection_method Optical
ra 296.1128°
decl -2.9584°
Circular_text TITLE: GCN CIRCULAR NUMBER: 15304 SUBJECT: GRB 131004A: optical afterglow from the NOT DATE: 13/10/04 22:44:30 GMT FROM: Daniele Malesani at Dark Cosmology Centre, Niels Bohr Inst D. Xu, D. Malesani, J. Hjorth (DARK/NBI), P. Jakobsson (Univ. Iceland), T. Kruehler (ESO Santiago), Nicolaas Groeneboom, and Anders Hafreager (Univ. Oslo), report: We observed the field of GRB 131004A (Hagen et al., GCN 15303) using the NOT equipped with AlFOSC. Consistent with the XRT position, we detect a new source at coordinates: RA = 19:44:27.08 Dec = -02:57:30.2 The source is not visible in the DSS, and brighter than its limiting magnitude, hence it is very likely the afterglow of GRB 131004A. At a time of 0.43 hr after the GRB, we measure R = 20.2 +- 0.1 mag compared to nearby USNO-B1 R2 magnitudes, where the error is mostly due to calibration.
GCN 15305 table
GRB_name GRB131004A
GCN_number 15305
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 15305 SUBJECT: GRB 131004A: TNG optical afterglow confirmation DATE: 13/10/04 23:38:34 GMT FROM: Paolo D'Avanzo at INAF-OAB D. Malesani (DARK/NBI), P. D'Avanzo (INAF-OAB), L. di Fabrizio, G. Tessicini (INAF-TNG) report on behalf of the CIBO collaboration: We observed the field of the possible short GRB 131004A (Hagen et al. GCN 15303) with the Italian 3.6m TNG telescope located in Canary Islands, equipped with the DOLoRes imager. The optical candidate reported by Xu et al (GCN 15304) is clearly seen in a 60 s R-band image taken at a mid t-t0=1.1 hours. From a preliminary photometry we estimate for this source a magnitude of R = 20.8 +/- 0.1 (calibrated against the USNOB1 catalogue). Given the evidence of fading with respect to the report of Xu et al. (GCN 15304) we confirm this source as the optical afterglow of GRB 131004A. The inferred power-law decay index is alpha=0.59 +/- 0.15. We acknowledge the TNG visitor astronomer X. Dumesque for support.
GCN 15306 table
GRB_name GRB131004A
GCN_number 15306
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 15306 SUBJECT: GRB 131004A: Liverpool Telescope optical afterglow observations DATE: 13/10/05 00:06:15 GMT FROM: Drejc Kopac at Math Phys U,Slovenia D. Kopac (U. Ljubljana), R. J. Smith (LJMU), C. G. Mundell (LJMU), N. R. Tanvir (U. Leicester) and A. Gomboc (U. Ljubljana), on behalf of a large collaboration report: The 2-m Liverpool Telescope automatically began observing the field of GRB 131004A (Hagen et al., GCN 15303). We detect the optical afterglow in the position consistent with the NOT (Xu et al., GCN 15304) and TNG (Malesani et al., GCN 15305). Our preliminary photometry yields: Mid time from Exp Filter Magnitude trigger (min) (sec) ------------------------------------------- 85.1 300 i' 20.2 +- 0.1 111.3 300 i' 20.6 +- 0.1 ------------------------------------------- The magnitudes are calibrated agains I magnitudes of nearby USNO-B1.0 stars and are not corrected for the Galactic extinction.
GCN 15307 table
GRB_name GRB131004A
GCN_number 15307
Detection_method Optical
redshift 0.7170
Circular_text TITLE: GCN CIRCULAR NUMBER: 15307 SUBJECT: GRB131004A: Magellan Redshift DATE: 13/10/05 00:56:31 GMT FROM: Ryan Chornock at Harvard R. Chornock, R. Lunnan, and E. Berger (Harvard) report: We observed the optical afterglow (Xu et al., GCN 15304; Malesani et al., GCN 15305; Kopac et al., GCN 15306) of the possible short GRB 131004A (Hagen et al., GCN 15303) using LDSS-3 on the 6.5-m Magellan Clay Telescope. A sequence of 3x1200s spectroscopic exposures of the afterglow began at 23:44 on 4 October UT. A preliminary reduction reveals a flat continuum with superposed weak emission lines from [O II], H-beta, and [O III] at a common redshift of 0.717. Possible weak features consistent with Ca II H+K absorption at this same redshift are also present.
GCN 15308 table
GRB_name GRB131004A
GCN_number 15308
Detection_method Swift-XRT Det
ra 296.1133°
decl -2.9586°
Circular_text TITLE: GCN CIRCULAR NUMBER: 15308 SUBJECT: GRB 131004A: Enhanced Swift-XRT position DATE: 13/10/05 03:15:17 GMT FROM: Phil Evans at U of Leicester P.A. Evans, M.R. Goad, J.P. Osborne and A.P. Beardmore (U. Leicester) report on behalf of the Swift-XRT team. Using 465 s of XRT Photon Counting mode data and 1 UVOT images for GRB 131004A, 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 = 296.11332, -2.95861 which is equivalent to: RA (J2000): 19h 44m 27.20s Dec (J2000): -02d 57' 31.0" 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.
GCN 15309 table
GRB_name GRB131004A
GCN_number 15309
Detection_method GROND
Circular_text TITLE: GCN CIRCULAR NUMBER: 15309 SUBJECT: GRB 131004A: GROND observations of the afterglow DATE: 13/10/05 08:38:02 GMT FROM: Sebastian Schmidl at TLS Tautenburg S. Schmidl, A. Nicuesa Guelbenzu, S. Klose (all TLS Tautenburg), and J. Greiner (MPE Garching) report on behalf of the GROND team: We observed the field of GRB 131004A (Swift trigger 573190; Hagen et al., GCN 15303) 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 on October 4, 2013, at 23:41 UT, 2 hrs after the GRB trigger. They were performed at an average seeing of 0".9 and at an average airmass of 1.1. The optical afterglow, discovered by Xu et al. (GCN 15304), is clearly detected. Based on a total exposure time of 460 s in g'r'i'z' and 480 s in JHK, at a midtime of 2.75 hrs after the burst, we measure the following preliminary AB magnitudes: g' = 22.9 +/- 0.1, r' = 22.1 +/- 0.1, i' = 21.6 +/- 0.1, z' = 21.4 +/- 0.1, J = 20.2 +/- 0.2, H = 20.2 +/- 0.2, and K > 19.8 . Given magnitudes are calibrated against GROND zeropoints as well as 2MASS field stars and are not corrected for the expected Galactic foreground extinction corresponding to a reddening of E_(B-V)=0.29 mag in the direction of the burst (Schlegel et al. 1998).
GCN 15310 table
GRB_name GRB131004A
GCN_number 15310
Detection_method Optical
redshift 0.7100
Circular_text TITLE: GCN CIRCULAR NUMBER: 15310 SUBJECT: GRB131004A: TNG Redshift confirmation DATE: 13/10/05 09:32:49 GMT FROM: Valerio D'Elia at ASDC V. D'Elia (INAF-OAR/ASDC), P. D'Avanzo (INAF-OAB), D. Malesani (DARK/NBI), L. di Fabrizio, G. Tessicini (INAF-TNG) report on behalf of the CIBO collaboration: We observed the optical afterglow (Xu et al., GCN 15304; Malesani et al., GCN 15305; Kopac et al., GCN 15306) of the possible short GRB 131004A (Hagen et al., GCN 15303) using DOLORES/LR-B (wavelength range: 3000-8000 AA) on the 4-m TNG Telescope at Canary islands. We obtain a 1800 s spectrum starting at 2013-10-04 23:00:38 UT, i.e., 1.33 hr from the burst. A preliminary reduction reveals weak emission lines from [O II], H-gamma and H-delta at a common redshift of 0.71. We thus confirm the redshift reported by Chornock et al. (GCN 15307). ---------------------------------------------------------------- This message was sent using IMP, the Internet Messaging Program.
GCN 15311 table
GRB_name GRB131004A
GCN_number 15311
Detection_method Swift-XRT Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 15311 SUBJECT: GRB 131004A: Swift-XRT refined Analysis DATE: 13/10/05 11:54:05 GMT FROM: Phil Evans at U of Leicester C. Pagani (U. Leicester), P. D'Avanzo (INAF-OAB), V. D'Elia (ASDC), A. Maselli (INAF-IASFPA), D.N. Burrows (PSU), J.A. Kennea (PSU), V. Mangano (PSU), A.P. Beardmore (U. Leicester), P.A. Evans (U. Leicester) and report on behalf of the Swift-XRT team: report on behalf of the Swift-XRT team: We have analysed 9.1 ks of XRT data for GRB 131004A, from 79 s to 34.7 ks after the BAT trigger. The data are entirely in Photon Counting (PC) mode. the light curve is consistent with a constant source of mean count rate 7.4e-02 ct/sec. A power-law fit gives an index of 0.1 (+2.0, -1.6). A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 2.16 (+0.27, -0.26). The best-fitting absorption column is 3.1 (+1.0, -0.9) x 10^21 cm^-2, in excess of the Galactic value of 7.0 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 3.9 x 10^-11 (6.8 x 10^-11) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Total column: 3.1 (+1.0, -0.9) x 10^21 cm^-2 Galactic foreground: 7.0 x 10^20 cm^-2 Excess significance: 4.7 sigma Photon index: 2.16 (+0.27, -0.26) If the light curve continues to decay with a power-law decay index of 0.1, the count rate at T+24 hours will be 0.029 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.1 x 10^-12 (1.9 x 10^-12) erg cm^-2 s^-1. The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00573190. This circular is an official product of the Swift-XRT team.
GCN 15312 table
GRB_name GRB131004A
GCN_number 15312
Detection_method Swift-XRT Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 15312 SUBJECT: GRB 131004A: RATIR Optical and NIR Upper Limits DATE: 13/10/05 15:33:25 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 (UCSC), Eleonora Troja (GSFC), Enrico Ramirez-Ruiz (UCSC), Jos A. de Diego (UNAM), Leonid Georgiev (UNAM), Jess Gonzlez (UNAM), Carlos Romn-Ziga (UNAM), Neil Gehrels (GSFC), and Harvey Moseley (GSFC) report: We observed the field of GRB 131004A (Hagen, et al., GCN 15303) with the Reionization and Transients Infrared Camera (RATIR; www.ratir.org) on the 1.5m Harold Johnson Telescope at the Observatorio Astronmico Nacional on Sierra San Pedro Mrtir from 2013/10 5.12 to 2013/10 5.30 UTC (5.12 to 9.44 hours after the BAT trigger), obtaining a total of 2.17 hours exposure in the r and i bands and 0.94 hours exposure in the Z, Y, J, and H bands. For a source within the Swift-XRT error circle, in comparison with 2MASS, we obtain the following upper limits (3-sigma): r > 23.91 i > 23.33 Z > 22.56 Y > 21.86 J > 21.81 H > 21.26 These magnitudes are in the AB system and are not corrected for Galactic extinction in the direction of the GRB. We did not detect the source reported in Xu et al. (GCN 15304). In comparison with earlier GROND observations (Schmidl, et al., GCN 15309) the source has faded by a minimum of 1.7 magnitudes in the r band. This implies a power-law decay steeper than t^-1.7. We thank the staff of the Observatorio Astronmico Nacional in San Pedro Mrtir.
GCN 15313 table
GRB_name GRB131004A
GCN_number 15313
Detection_method Swift-UVOT Det
ra 296.1129°
decl -2.9584°
Circular_text TITLE: GCN CIRCULAR NUMBER: 15313 SUBJECT: GRB 131004A: Swift/UVOT Detection DATE: 13/10/05 16:42:18 GMT FROM: MSSL Swift/UVOT team at MSSL/Swift M. De Pasquale (UCL-MSSL) and L. M. Z. Hagen (PSU) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 131004A 75 s after the BAT trigger (Hagen et al., GCN Circ. 15303). A source consistent with the XRT position (Evans et al. GCN Circ. 15308) and the position of the source given in Xu et al. (GCN Circ. 15304) is detected in the initial and summed UVOT exposures. The preliminary coordinates of this source are: RA (J2000) = 19:44:27.09 = 296.11287 (deg.) Dec (J2000) = -02:57:30.4 = -2.95844 (deg.) with an estimated uncertainty of 0.55 arc sec. (radius, 90% confidence). Preliminary detections 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 75 225 147 19.23 ± 0.11 white 75 5688 520 20.18 ± 0.12 u_FC 288 537 246 19.96 ± 0.34 u 288 6715 659 20.72 ± 0.40 v 617 6100 432 >20.24 b 543 6770 285 >21.0 w1 666 6510 432 >20.9 m2 814 6305 413 >20.8 w2 593 5895 432 >21.0 The magnitudes in the table are not corrected for substantial Galactic extinction due to the reddening of E(B-V) = 0.28 in the direction of the burst (Schlegel et al. 1998).
GCN 15314 table
GRB_name GRB131004A
GCN_number 15314
Detection_method Swift-XRT Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 15314 SUBJECT: GRB 131004A: CARMA 93 GHz upper limit DATE: 13/10/05 19:11:45 GMT FROM: Ashley Zauderer at CfA B. A. Zauderer, E. Berger, W. Fong (Harvard) report on behalf of a larger collaboration and the CARMA Key Project "A Millimeter View of the Transient Universe": "We observed the position of GRB 131004A (Hagen et al., GCN 15303) with CARMA at a mean frequency of 93 GHz beginning 2013 October 5.04 (dt=3.4 hours). We do not find significant radio emission at the position of the enhanced Swift-XRT and UVOT localizations (Evans et al., GCN 15308; De Pasquale et al., GCN 15313), or the optical afterglow detection (Xu et al., GCN 15304), to a 3-sigma upper limit of ~0.3 mJy. No further radio observations are planned. We thank the CARMA staff for prompt execution of these observations."
GCN 15315 table
GRB_name GRB131004A
GCN_number 15315
Detection_method Fermi GBM Det
t_trigger 21:41:03.680 UTC
Circular_text TITLE: GCN CIRCULAR NUMBER: 15315 SUBJECT: GRB 131004A: Fermi GBM observation DATE: 13/10/06 02:20:22 GMT FROM: Shaolin Xiong at UAH Shaolin Xiong (UAH) reports on behalf of the Fermi GBM Team: "At 21:41:03.68 UT on 04 October 2013, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 131004A (trigger 402615666 / 131004904), which was also detected by the Swift/BAT (Hagen et al. 2013, GCN 15303). The GBM on-ground location is consistent with the Swift position. The angle from the Fermi LAT boresight is 93 degrees. The GBM light curve consists of multiple pulses with a duration (T90) of about 1.4 s (50-300 keV). The time-averaged spectrum from T0-0.19 s to T0+0.58 s is well fit by a simple power law function with index -1.75 +/- 0.06. The event fluence (10-1000 keV) in this time interval is (6.2 +/- 0.6)E-7 erg/cm^2. The 64 ms peak photon flux measured starting from T0+0.192 s in the 10-1000 keV band is 10.4 +/- 1.6 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."
GCN 15316 table
GRB_name GRB131004A
GCN_number 15316
Detection_method Swift-BAT Det
ra 296.1080°
decl -2.9520°
Circular_text TITLE: GCN CIRCULAR NUMBER: 15316 SUBJECT: GRB 131004A, Swift-BAT refined analysis DATE: 13/10/06 04:09:43 GMT FROM: Amy Lien at GSFC M. Stamatikos (OSU), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC), L. M. Z. Hagen (PSU), H. A. Krimm (GSFC/USRA), A. Y. Lien (NASA/GSFC/ORAU), C. B. Markwardt (GSFC), J. Norris (BSU), D. M. Palmer (LANL), T. Sakamoto (AGU), G. Sato (ISAS), J. Tueller (GSFC), T. N. Ukwatta (MSU) (i.e. the Swift-BAT team): Using the data set from T30 to T+62 sec from the recent telemetry downlink, we report further analysis of BAT GRB 131004A (trigger #573190) (Hagen, et al., GCN Circ. 15303). The BAT ground-calculated position is RA, Dec = 296.108, -2.952 deg which is RA(J2000) = 19h 44m 26.0s Dec(J2000) = -02d 57' 05.6" with an uncertainty of 1.1 arcmin, (radius, sys+stat, 90% containment). The partial coding was 73%. The mask-weighted light curve shows a single short spike starts at ~T-0.18, peaks at ~T0, and ends at ~T+1.35. T90 (15-350 keV) is 1.54 +- 0.33 sec (estimated error including systematics). The time-averaged spectrum from T-0.25 to T+1.80 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.81 +- 0.11. The fluence in the 15-150 keV band is 2.8 +- 0.2 x 10^-07 erg/cm2. The 1-sec peak photon flux measured from T-0.27 sec in the 15-150 keV band is 3.4 +- 0.2 ph/cm2/sec. All the quoted errors are at the 90% confidence level. The burst spectrum appears at the softer end of short bursts, which have an average spectral index of 1.2 when fitting with a simple power-law model (Sakamoto et al. 2011). The spectral lag for this burst is 0.130 s +- 0.020 s (for the 50-100 keV and 15-25 keV bands), which is significantly longer than those of regular short bursts. The results of the batgrbproduct analysis are available at http://gcn.gsfc.nasa.gov/notices_s/573190/BA/
GCN 15317 table
GRB_name GRB131004A
GCN_number 15317
Detection_method Swift-XRT Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 15317 SUBJECT: GRB 131004A: Skynet PROMPT/DSO-14 upper limits DATE: 13/10/07 04:17:33 GMT FROM: Nathan Frank at U.North Carolina N. Frank, A. Trotter, D. Reichart, J. Haislip, A. LaCluyze, A. Smith, D. Caton, L. Hawkins, T. Berger, H. T. Cromartie, R. Egger, A. Foster, K. Ivarsen, M. Maples, J. Moore, M. Nysewander, E. Speckhard, and J. A. Crain report: Skynet observed the Swift/XRT localization of the field of GRB 131004A (Hagen et al., GCN 15303, Swift trigger # 573190) with four 16" telescopes of the PROMPT array at CTIO, Chile and with the 14" telescope at the Appalachian State University Dark Sky Observatory (DSO), North Carolina, starting at 2013-10-04, 23:39:35 UT and continuing until 2013-10-05, 02:21:12 UT (t=1.9-4.7h post-trigger). Skynet took a total of 220 160s exposures simultaneously in each of the BVRI bands. In stacked images, we do not detect any uncatalogued optical source in any band at or near the reported position. The 3-sigma limiting magnitudes of our images are: ============================================== t(mean) telescope band exposures 3-sig lim mag ------------------------------------------------------------------------- 2.5h Prompt3 B 25x160s 18.98 2.7h Prompt1 V 32x160s 21.56 3.4h Prompt4 R 55x160s 21.85 3.5h Prompt5 I 50x160s 21.12 2.9h DSO-14 I 7x160s 18.46 ============================================== Magnitudes are in the Vega system, calibrated to five APASS stars in the field. Magnitudes have not been corrected for line-of-sight Milky Way dust extinction, with expected E(B-V)=0.28 (Schlegel et al. 1998). No further Skynet observations are scheduled.
GCN 15318 table
GRB_name GRB131004A
GCN_number 15318
Detection_method Swift-XRT Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 15318 SUBJECT: GRB 131004A: Correction to XRT refined analysis DATE: 13/10/07 07:09:57 GMT FROM: Phil Evans at U of Leicester P.A. Evans (U. Leicester) reports on behalf of the Swift-XRT team, There was a mistake in the "Swift-XRT refined analysis" circular (GCN Circ. 15311) in which it was erroneously stated that the light curve was consistent with a constant source. In fact, the light curve is decaying as a power-law with an index of 1.01 (+/- 0.07). We apologise for any confusion caused. As ever, the full light curve and related GRB products are online at http://www.swift.ac.uk/xrt_products/00573190 This circular is an official product of the Swift-XRT team.
GCN 15319 table
GRB_name GRB131004A
GCN_number 15319
Detection_method Swift-BAT Det
redshift 0.7170
Circular_text TITLE: GCN CIRCULAR NUMBER: 15319 SUBJECT: GRB 131004A: MOSFIRE NIR imaging DATE: 13/10/08 09:31:30 GMT FROM: Daniel Perley at Caltech D. A. Perley (Caltech) reports: I imaged the location of GRB 131004A (GCN 15303) in Ks-band with MOSFIRE on the Keck I telescope on the night of 2013-10-07 for a total integration time of 291 seconds under good seeing conditions but some cloud cover. The midpoint of the integration was 07:21 UT, 2.40 days after the GRB. At the location of the optical transient reported by Xu et al. (GCN 15304), no source is detected to a limiting magnitude of Ks > 20.6. The nearest detected object to this location is a faint (Ks = 19.7), compact source approximately 1.4 arcsec to the west, at RA=19:44:26.99, dec=-02:57:30.15. Given the moderate redshift of z=0.717 (Chornock et al., GCN 15307), these results suggest either that the host of this event is a relatively low-mass galaxy or that the GRB exploded outside the bulk of the stellar light of its host. The >1.5 sec duration and significant lag reported in the BAT refined analysis (Lien et al., GCN 15316) may suggest the former interpretation is more likely. I thank D. Malesani for providing the NOT image to verity the location of the optical transient.