//////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4171 SUBJECT: GRB051028:MASTER optical observations DATE: 05/10/28 18:21:57 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, V.Kornilov, D.Kuvshinov, N.Tyurina, A.Belinski, E.Gorbovskoy, A.Krylov, G.Borisov, A.Sankovich, V.Vladimirov Sternberg Astronomical Institute, Moscow Union 'Optic' MASTER robotic system (http://observ.pereplet.ru) responded to HETE GRB051028.6 . An automated response took first image 2005-10-28 16:59:56 UT, 03h 23 m after the GRB time. The unfiltered image is calibrateds relative to USNO A2.0 (0.8 R + 0.2 B). Reduction is continued. The robot not find OT-candidate in error box brighter then 17.0. This work is supported by RFFI 04-02-16411 grant. This message can be cited. Mailto: lipunov@sai.msu.ru //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4172 SUBJECT: GRB 051028 (=H3951): A GRB localized by HETE DATE: 05/10/28 19:28:06 GMT FROM: Roland Vanderspek at MIT GRB 051028 (=H3951): A GRB localized by HETE K. Hurley, G. Ricker, J-L. Atteia, N. Kawai, D. Lamb, and S. Woosley, on behalf of the HETE Science Team; M. Arimoto, T. Donaghy, E. Fenimore, M. Galassi, C. Graziani, N. Ishikawa, A. Kobayashi, J. Kotoku, M. Maetou, M. Matsuoka, Y. Nakagawa, T. Sakamoto, R. Sato, T. Shimokawabe, Y. Shirasaki, S. Sugita, M. Suzuki, T. Tamagawa, K. Tanaka, and A. Yoshida, on behalf of the HETE WXM Team; N. Butler, G. Crew, J. Doty, G. Prigozhin, R. Vanderspek, J. Villasenor, J. G. Jernigan, A. Levine, G. Azzibrouck, J. Braga, R. Manchanda, and G. Pizzichini, on behalf of the HETE Operations and HETE Optical-SXC Teams; M. Boer, J-F Olive, and J-P Dezalay, on behalf of the HETE FREGATE Team; report: At 13:36:01.47 UTC (48961.47 s UT) on 28 Oct 2005, the HETE FREGATE and WXM instruments detected event H3951, a bright GRB. The burst triggered FREGATE in the 30-400 keV energy band. The burst duration (T90) was 16 seconds in both the 30-400 keV band and the 7-30 keV band. Ground analysis of the WXM data produces a 90% confidence error region measuring 33 x 18 arcminutes with corners at the following coordinates: RA = 01h 50m 19.6s, Dec = +47d 41m 06s RA = 01h 47m 01.1s, Dec = +47d 38m 02s RA = 01h 46m 58.3s, Dec = +47d 55m 55s RA = 01h 50m 17.5s, Dec = +47d 58m 58s The 30-400 keV fluence of GRB 051028 is 6e-6 erg/cm2; the 2-30 keV fluences is 6e-7 erg/cm2. The hardness ratio allows us to classify this burst as a classical GRB. Further information will be available at http://space.mit.edu/HETE/Bursts/GRB051028 //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4173 SUBJECT: GRB051028:MASTER observations DATE: 05/10/28 21:29:54 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, V.Kornilov, D.Kuvshinov, N.Tyurina, A.Belinski, E.Gorbovskoy, A.Krylov, G.Borisov, A.Sankovich, G. Antipov, V.Vladimirov Sternberg Astronomical Institute, Moscow Union 'Optic' MASTER robotic system (http://observ.pereplet.ru) responded to HETE GRB051028.6 (GCN 4172). An automated response took first image 2005-10-28 16:59:56 UT, 03h 23 m after the GRB time (GCN4171). The unfiltered image is calibrated relative to USNO A2.0 (0.8 R + 0.2 B). We not find OT-candidate in error box brighter then 17.9 on the summ of 9 images between 17 32 40 - 18 03 03 UT. Mean time is 17 48 09 ( 4 h 12 min after GRB Time). The JPG-image of the summ will be available at http://observ.pereplet.ru/images/GRB050828/1.jpg (In error circ you can see candidates which we recognised with 2MASS ). The reduction is continuing. This work is supported by RFFI 04-02-16411 grant. This message can be cited. Mailto: lipunov@sai.msu.ru //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4174 SUBJECT: GRB051028: Swift XRT Position DATE: 05/10/29 05:11:11 GMT FROM: Judith Racusin at PSU J. Racusin (PSU), K. Page (U. Leicester), J. Kennea, D. Morris, C. Pagani, D. Burrows (PSU), N. Gehrels (GSFC) on behalf of the Swift XRT team: The Swift XRT began observing the field of the HETE discovered GRB 051028 (Hurley et al., GCN 4172) at 20:44:08 UT, approximately 7.1 hours after the trigger. We have analyzed the first 3 orbits of data and we detect an uncatalogued fading X-ray source at the following coordinates: RA(J2000): 01 48 15.1 Dec(J2000): +47 45 12.5 with an estimated uncertainty of 6 arcseconds (90% containment), including corrections for the XRT boresight offset. This position is 5.2 arcminutes from the center of the HETE error box reported in Hurley et al. (GCN 4172). Note that the HETE error box quoted in Hurley et al. (GCN4172) actually extends beyond the field of view of the XRT. However, the source mentioned above is the only bright source in the field and is decaying. Therefore, it is likely the afterglow of GRB051028. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4175 SUBJECT: GRB051028: WHT optical candidate DATE: 05/10/29 05:34:42 GMT FROM: Martin Jelinek at Inst.Astrophys.Andalucia,Granada M. Jelinek, S.B.Pandey, S.S.Guziy, A.J.Castro-Tirado, J. Gorosabel, A. de Ugarte Postigo, and S. Vitek (IAA CSIC Granada, Spain) and J.T.A. De Jong, (Max Planck Intitut fuer Astronomie, Heidelberg, Germany) report We have observed the complete errorbox of HETE trigger 3951 (Hurley et al, GCN 4172) with the prime focus camera of William Herschel Telescope at La Palma starting 21:42UT (ie. ~7h after the GRB). We detect an object within the XRT errorbox (Racusin et al, GCN 4174) at coordinates RA 01:48:15.01 Dec 47:45:09.2 (+/- 1.0", J2000), with a rough magnitude R=22, which is not present in DSS. Further observations will be needed to confirm whether this is indeed the optical afrterglow of GRB051028. The image limit is ~24.2. This message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4176 SUBJECT: GRB051028: confirmation of the afterglow DATE: 05/10/29 07:06:49 GMT FROM: Martin Jelinek at Inst.Astrophys.Andalucia,Granada S.B.Pandey, M. Jelinek, S.S.Guziy, A.J.Castro-Tirado, J. Gorosabel, A. de Ugarte Postigo, and S. Vitek (IAA CSIC Granada, Spain) and J.T.A. De Jong, (Max Planck Intitut fuer Astronomie, Heidelberg, Germany) report: Further monitoring of the afterglow candidate (Jelinek et al. 7145) using 4.2 meter William Herschel Telescope confirms the decay nature of the source, suggesting the source is really the optical afterglow of GRB 051028. Our observation 15 h after the burst show that the OT magnitude has decayed considerably and it is around 23 in R band. We have posted the searchmap to the following website: http://lascaux.asu.cas.cz/mates/grb051028.gif This message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4177 SUBJECT: GRB051028: Swift/UVOT upper limits DATE: 05/10/29 15:16:45 GMT FROM: Alexander Blustin at MSSL-UCL A. J. Blustin, M. J. Page, M. De Pasquale, S. R. Oates (UCL-MSSL), K. Hurley (Berkeley), M. Chester (PSU), N. Gehrels (GSFC) report on behalf of the Swift/UVOT team: The Swift/UVOT began observing the field of GRB 051028 at 20:44:06 UT on 2005-10-28, 7.1 hours after the HETE trigger (Hurley et al. GCN 4172). No new source (with respect to the DSS) was detected at the XRT (Racusin et al. GCN 4174) or WHT (Jelinek et al. GCN 4175, Pandey et al. GCN 4176) positions in summed images from the four UVOT filters used down to the following 3-sigma upper limits: Filter T_range(hours) Exp(sec) 3sigUL V 7.4-10.3 1441 20.2 W1 8.7-10.8 1700 21.1 M2 8.5-10.5 1763 21.4 W2 7.1-9.1 1456 21.4 We note that this burst is at low galactic latitude, with an E(B-V) of 0.21 and A_v of 0.71 mag. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4178 SUBJECT: GRB051028: optical observations DATE: 05/10/29 17:37:08 GMT FROM: Patrizia Ferrero at TLS Tautenburg P. Ferrero, D. A. Kann, S. Klose, and C. Hoegner, Thueringer Landessternwarte Tautenburg, report: We observed the entire error box of GRB 051028 (HETE trigger 3951; Hurley et al. 2005, GCN 4172) with the 1.34-m Tautenburg Schmidt telescope equipped with the prime focus CCD camera on October 28, 2005. Sky conditions were very good. We obtained 6x180s I-band images (mean time Oct. 28.716 UT), 6x180s R-band images (mean time Oct. 28.739 UT), 6x180s V-band images (mean time Oct. 28.77 UT) and a final set of 60x180s I-band images (mean time Oct. 28.898 UT), corresponding to 3.58, 4.12, 4.88 and 7.94 hours after the burst, respectively. In our stacked images we clearly detect the afterglow candidate (Jelinek et al. 2005, GCN 4175; Pandey et al. 2005, GCN 4176) in all bands. A preliminary estimation of the afterglow magnitude on the first six co-added I-band images gives I~19, in comparison with the USNOB.1 star 1377-0047752 at R.A. (J2000)=01h 48m 15.974s and Decl.=+47d 45' 02.34" (Monet et al. 2003). Further analysis is in progress. This message may be quoted. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4179 SUBJECT: GRB051028 SARA Observation DATE: 05/10/30 05:18:17 GMT FROM: Autumn Homewood at Clemson U Autumn Homewood, Kiran Garimella, Stephen Fuller and Dieter H. Hartmann, report on behalf of the Clemson GRB Follow-Up Team, and the FUN Collaboration: We imaged the central 8x12 arcmin field of the HETE error box for trigger 3951 (GCN 4172) with the SARA 0.9-m at Kitt Peak. We do not detect the OT reported by Jelinek, et al (GCN 4175). We began observations under cloudy conditions at UT 2005 Oct 29 02:27:55, approximately 11 hours after the burst, and stacked 18 R-band exposures of 180 seconds each. We derive a limiting magnitude of R=20.4 +/-0.3 mag. Images were calibrated using the USNO B1.0 Catalog. This message may be cited. The Clemson GRB Follow-Up Website can be found at: http://people.clemson.edu/~kgarime/burst The SARA website is located at: http://www.saraobservatory.org //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4182 SUBJECT: GRB051028:MASTER correction and final results DATE: 05/10/30 15:53:30 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, V.Kornilov, D.Kuvshinov, N.Tyurina, A.Belinski, E.Gorbovskoy, A.Krylov, G.Borisov, A.Sankovich, G. Antipov, V.Vladimirov Sternberg Astronomical Institute, Moscow Union 'Optic' MASTER robotic system (http://observ.pereplet.ru) responded to HETE GRB051028 (GCN 4172) at very nice Moscow weather. Unfortunately, the remoute observations was delayted due to manage computer problems. Now we find new earlier images. First image was at 2005-10-28 16:23:14 (not at 16:59:56 UT as we noted in GCN4171, GCN4173) i.e. 2h 46min after GRB time. The unfiltered image is calibrated relative to USNO A2.0 (0.8 R + 0.2 B). Final results: the uper limits on OT (M. Jelinek et al. GCN4175) are UT (start) T-T_GRB TotExpTime 3sigma limit 16:23:14 02h 46 m 45 s 17.9 16:59:56 03h 23 m 45 s 17.5 17:32:40 04h 12 m 360 s 18.3 20:01:04 06h 41 m 1050 s 19.6 21:46:43 08h 26 m 1200 s 19.4 This work is supported by RFFI 04-02-16411 grant. This message can be cited. Mailto: lipunov@sai.msu.ru //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4183 SUBJECT: Konus-Wind observation of GRB 051028 DATE: 05/10/31 11:17:25 GMT FROM: Valentin Pal'shin at Ioffe Inst S. Golenetskii, R.Aptekar, E. Mazets, V. Pal'shin, D. Frederiks, and T. Cline on behalf of the Konus-Wind team report: The GRB 051028 (HETE trigger #3951; Hurley et al., GCN 4172) triggered Konus-Wind at T0=48967.159 s UT (13:36:07.159) The time-integrated spectrum of the GRB (from T0 to T0+8.448 sec) is well fitted (in the 20 keV - 2 MeV range) by a power law with exponential cutoff model: dN/dE ~ E^(-alpha) * exp(-E/E0) with alpha = 0.73 (-0.26, +0.22) and E0 = 236 (-68, +110) keV (chi^2 = 61/62 dof). The peak energy Ep = 298 (-50, +73) keV. It can also be fitted by GRBM (Band) model for which: the low-energy photon index is alpha = -0.47 (-0.37, +0.57), the high energy photon index beta < -1.97, the break energy E0 = 150 (-69, +118) keV. As observed by Konus-Wind the burst had a duration ~12 sec, fluence 6.78(-1.08, +0.61)x10^-6 erg/cm2 and peak flux on 256-ms time scale 1.29(-0.24, +0.15)x10^-6 erg/cm2/sec (both in the 20 keV - 2 MeV energy range). All the quoted errors are at the 90% confidence level. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4184 SUBJECT: Recent GRB UBVRcIc field photometry DATE: 05/10/31 16:31:02 GMT FROM: Arne A. Henden at AAVSO A. Henden (AAVSO/USNO) reports on behalf of the USNO GRB Team: We have acquired UBVRcIc all-sky photometry for 23x23arcmin fields centered on the coordinates of recent GRB localizations with the USNOFS 1.0-m telescope on 1 or 2 photometric nights. We are using a new CCD, and so place an additional zeropoint error of about 0.03mag that should be added in quadrature to the errors reported in the files listed below. Stars brighter than V=13.0 are saturated and should be used with care. We have placed the photometric data on our anonymous ftp site: ftp://ftp.nofs.navy.mil/pub/outgoing/aah/grb/grb050505.dat ftp://ftp.nofs.navy.mil/pub/outgoing/aah/grb/grb051021.dat ftp://ftp.nofs.navy.mil/pub/outgoing/aah/grb/grb051022.dat ftp://ftp.nofs.navy.mil/pub/outgoing/aah/grb/grb051028.dat Since these bursts had identified optical afterglows, we may improve the photometric calibration on subsequent observing runs. As always, you should check the dates on the .dat file prior to final publication to get the latest photometry. There is a README file on the ftp directory to give you information about the procedures used to calibrate these fields. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4205 SUBJECT: GRB051028: Swift-XRT refined analysis DATE: 05/11/07 12:03:55 GMT FROM: Kim Page at U.of Leicester K.L. Page, M.R. Goad (U. Leicester), D.N. Burrows, J. Racusin (PSU), S. Oates (MSSL), M. Ajello (MPE) and M. Trippico (GSFC-SSAI) report on behalf of the Swift XRT team: We have analysed 38 ks of XRT observations of the HETE burst GRB051028 (trigger number H3951; GCN 4172, Hurley et al.), between approximately 7.1 and 178 hours after the trigger. As reported in GCN 4174 (Racusin et al.), there is an uncatalogued, fading X-ray source within the HETE error circle. The refined coordinates for this X-ray afterglow are: RA(J2000): 01 48 15.1 Dec(J2000): +47 45 12.9 with an estimated uncertainty of 3.8 arcsec (90% containment) and including the latest XRT boresight correction. The position is 0.6 arcsec from that given by Racusin et al. (GCN 4174) and 3.9 arcsec from the optical afterglow detected by the WHT (GCNs 4175, Jelinek et al., and 4176, Pandey et al.) The X-ray light-curve shows a simple power-law decay with a slope of 1.25 +0.25/-0.16. The spectrum of the full 38 ks of data can also be modelled with a power-law, with photon index, Gamma = 1.74 +/- 0.21. There is no evidence for an absorbing column higher than the Galactic value of 1.2e21 cm^-2. At 7.1 hours, the 0.3-10 keV observed (unabsorbed) flux was ~1.8e-12 (2.2e-12) erg cm^-2 s^-1. At 178 hours, the afterglow had faded to an observed (unabsorbed) flux level of 2.3e-14 (2.8e-14) erg cm^-2 s^-1. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4278 SUBJECT: GRB 051028 Optical Observations DATE: 05/11/16 15:03:15 GMT FROM: T.P. Prabhu at Indian Astro. Obs. D.K. Sahu, S. Srividya and S. Vanniarajan (Indian Institute of Astrophysics, Bangalore,India) communicate on behalf of a larger Indian collaboration: We observed the central 10x10 arcmin region of the error circle of the HETE trigger 3951 in Bessell R and I filters with the 2-m Himalayan Chandra Telescope, Hanle, India, starting from 16:15 UT, 2005 October 28 (about 2.7 hours after the burst). We could clearly detect the OT of GRB 051028 reported by Jelinek et al. (GCN 4175). The preliminary R band magnitude for the OT, estimated using the calibration provided by Henden (GCN 4184), is R=20.77+/-0.10 at 16:18 UT. The OT decayed by ~1.3 mag in R band in 1.5 hours. Further analysis is in progress. This message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 5190 SUBJECT: GRB 051028 : WIDGET pre-trigger limit DATE: 06/05/31 11:41:11 GMT FROM: Toru Tamagawa at RIKEN K. Masuno, Y. Urata, M. Tashiro, K. Abe, K. Onda, N. Kodaka (Saitama-U), F. Usui (ISAS/JAXA), M. Kuwahara (TUS/RIKEN), T. Tamagawa (RIKEN) report: "We observed the error region of GRB 051028 (Hurley et al. GCN 4172) with the very wide-field camera WIDGET located at Akeno, Japan. WIDGET monitored the region with repeat of unfiltered 5-second exposures between 16.0 min and 11.2 min before the burst. We did not find any optical emission from the afterglow position (Jelinek et al. GCN 4175). The 1-sigma limiting magnitude of each frame derived by the Tycho-2 catalog was around V=10.3 magnitudes." This message may be cited.