YES, this is the file for what eventually got called the "B" burst. ////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 8600 SUBJECT: GRB 081203A: Burst detection from Swift-BAT slew data DATE: 08/12/03 18:54:02 GMT FROM: Antonio Copete at Harvard U A. Copete, J. Grindlay (Harvard) S. Barthelmy, C. Markwardt, N. Gehrels (NASA/GSFC) We report the detection of a GRB candidate by the BAT Slew Survey (BATSS) in the slew that started at 13:52:02 UT. This is 309 sec before the trigger time for the GRB that followed (A. M. Parsons et al, GCN 8595), which occurs at a different location and should hereafter be referred to as GRB 081203B. The ground-calculated position of GRB 081203A is RA, Dec = 228.789, +44.427 deg, which is RA (J2000) = 15h 15m 09s Dec (J2000) = +44d 25' 36" with an uncertainty of 3.04 arcmin (90% confidence, including systematics). The detection was triggered by simultaneous independent detections of 11.0 sigma and 5.6 sigma from imaging in the 15-50 keV and 50-150 keV energy bands, respectively. The burst mask- tagged lightcurve shows 2 main peaks, the larger one at T+24sec and lasting 2sec as the burst enters the BAT FoV, the second one at T +30sec with a duration of 2sec, and it has largely faded as the pointing observation that follows begins. The measured T90 = 23.4sec and T50 = 8.2sec (15-150keV). Preliminary spectral analysis from T+24.0 to T+50.4 shows a time- averaged spectrum that is best fit by a simple power law with photon index of 1.65. The total fluence in the 15-150 keV band is 2.1 x 10^-6 erg/cm2, and the 1-sec peak flux is 3.5 x 10^-7 erg/cm2/sec. A follow-up Swift ToO observation has been scheduled to begin at 18:26 UT, 4.6 hours after the burst. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 8602 SUBJECT: GRB 081203B: Naming correction for burst detected in Swift-BAT slew data DATE: 08/12/03 21:38:46 GMT FROM: Antonio Copete at Harvard U A. Copete, J. Grindlay (Harvard) S. Barthelmy, C. Markwardt, N. Gehrels, J. Cummings (NASA/GSFC), D. Palmer (LANL) We hereby correct the naming of the burst first reported by Copete et al (GCN 8600), which is unrelated to GRB 081203A (GCNs 8595, 8596, 8598, 8599 and 8601). Following the standard naming convention for same-day bursts to take into account the order of announcement, this burst must rather be named GRB 081203B. This name should be used in all follow-up circulars referring to this burst. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 8605 SUBJECT: GRB 081203B: Swift-XRT candidate afterglow. DATE: 08/12/03 23:13:37 GMT FROM: Boris Sbarufatti at INAF-IASF-Pa B. Sbarufatti, V. La Parola, V. Mangano (INAF-IASF Pa) report on behalf of the Swift-XRT team: Swift began observing the field of the Swift BAT Slew Survey (BATSS) GRB 081203B (Copete et al., GCN Circ. 8600, 8602) 16.7 ks after the trigger. Using 1419 s of XRT Photon Counting mode data we detect a single uncatalogued source inside the BAT error circle. Using the XRT data and 2 UVOT images, 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 = 228.7993, 44.4284 which is equivalent to: RA (J2000): 15 15 11.83 Dec (J2000): +44 25 42.3 with an uncertainty of 1.8 arcsec (radius, 90% confidence). The source lies 27 arcsec from the BAT centroid and has a count rate of ~5.5e-1 counts/s during this observation. It is not possible to determine whether this source is fading given the current statistics. Further observations are ongoing to clarify the nature of this source. This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 8606 SUBJECT: Swift/UVOT detection of GRB081203B DATE: 08/12/04 00:37:27 GMT FROM: Patricia Schady at MSSL/Swift P. Schady (MSSL-UCL), F.E. Marshall (NASA/GSFC) and B. Sbarufatti (INAF-IASF Pa) report on behalf of the Swift/UVOT team: The Swift/UVOT began white band observations of the field of the Swift BAT Slew Survey (BATSS) GRB 081203B 4.6 hrs after the BAT trigger (Copete et al., GCN Circ. 8600, 8602). An uncatalogued, fading source is clearly detected at RA(J2000.0) = 15:15:11.67 (228.79863 deg) DEC(J2000.0) = +44:25:42.9 (44.42859 deg) with an estimated uncertainty of 0.5 arcsec (radius, 90% confidence), consistent with the UVOT-enhanced XRT position (Sbarufatti et al., GCN Circ. 8605). The magnitudes of the first and last UVOT white band observations are reported below: Filter T_mid (s) Exp (s) Magnitude white 16746 154 18.29 +/- 0.04 white 22270 441 18.70 +/- 0.03 indicating a decay rate of alpha~1.0. The above magnitudes are not corrected for the Galactic extinction corresponding to a reddening of E_{B-V} = 0.02 mag (Schlegel et al., 1998, ApJS, 500, 525). The photometry is on the UVOT flight system described in Poole et al. (2008, MNRAS, 383,627). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 8607 SUBJECT: GRB 081203B: SDSS upper limits at the position of the optical afterglow DATE: 08/12/04 03:32:18 GMT FROM: Edo Berger at Harvard E. Berger (Harvard) reports: "Inspection of SDSS images at the position of the optical afterglow of BAT Slew Survey GRB 081203B (GCNs #8600,8606) reveals no coincident source to the following 3-sigma limits: u > 22.3 mag g > 23.5 mag r > 23.4 mag i > 22.6 mag z > 21.2 mag." //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 8608 SUBJECT: GRB 081203B: optical observations DATE: 08/12/04 04:13:20 GMT FROM: Alexei Pozanenko at IKI, Moscow M. Andreev, A. Sergeev, (Terskol Branch of Institute of Astronomy), Ju. Babina (CrAO) A. Pozanenko (IKI) on behalf of larger GRB follow up collaboration report: We observed the field of GRB 081203B detected by SWIFT in a slew mode (Copeteet al, GCN 8600) with the Z-600 telescope of Mt. Terskol observatory. A set of R-band exposures was taken starting Dec. 04 (UT) 01:44. In a combined image of 10x90 s taken at mid time Dec. 04 (UT) 01:53:45 we detect afterglow (Schady et al, GCN 8606) in coordinate (J2000) 15 15 11.66 +44 25 42.7. A preliminary photometry of the afterglow at Dec. 04 (UT) 01:53:45 is R=19.8. The photometry is based on USNO-A2.0 field stars. The combine image can be found at http://grb.rssi.ru/GRB081203B/grb081203B_Z600_01_53_45.jpg //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 8610 SUBJECT: Konus-Wind observation of GRB 081203B DATE: 08/12/04 12:34:28 GMT FROM: Valentin Pal'shin at Ioffe Inst S. Golenetskii, R.Aptekar, E. Mazets, V. Pal'shin, D. Frederiks, P. Oleynik, M. Ulanov, D. Svinkin, and T. Cline on behalf of the Konus-Wind team report: The long Swift-BATSS GRB 081203B (Copete et al., GCN 8600, 8602) triggered Konus-Wind at T0=49890.368 s UT (13:51:30.368). The burst light curve shows a multipeaked structure with a total duration of ~80 s. As observed by Konus-Wind the burst had a fluence of 5.56(-0.23, +0.24)x10^-5 erg/cm2, and a 256-ms peak flux measured from T0+10.032 s of 2.43(-0.40, +0.41)x10^-6 erg/cm2/s (both in the 20 keV - 2 MeV energy range). The time-integrated spectrum of the burst (from T0 to T0+64.000 s) can be fitted (in the 20 keV-2 MeV range) by a power law with exponential cutoff model: dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep) with alpha = -1.165(-0.054, +0.057), and Ep = 255(-19, +22) keV (chi2 = 77.8/61 dof). Fitting by GRB (Band) model yields the same alpha and Ep, and only an upper limit on the high energy photon index: beta < -2.59 (chi2 = 77.7/60 dof). All the quoted errors are at the 90% confidence level. The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB081203_T49890/ [GCN OPS NOTE(04dec08): Per author's request, the authors were added.] //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 8612 SUBJECT: Swift-XRT observations of GRB 081203B DATE: 08/12/04 16:44:11 GMT FROM: Boris Sbarufatti at INAF-IASF-Pa B. Sbarufatti, V. La Parola, V. Mangano (INAF IASF-Pa) report on behalf of the Swift-XRT team. We report on Swift-XRT observations of GRB 081203B (Copete et al. GCN Circ. 8600,8602). We analyzed 3.2 ks of Photon Counting mode data for this burst, covering times from T+17 ks to T+ 47 ks. The source reported in Sbarufatti et al. (GCN Circ. 8605) and confirmed as the afterglow by Schady et al. (GCN Circ. 8606) is fading following a power-law decay with index alpha=-1.4 (+0.2/-0.1). The spectrum for the first data sequence, corresponding to a 1.96 ks exposure and covering times from T+17 ks to T+23 ks can be fit by a power-law with photon index 2.1+/-0.2, with an absorbing column of (7.4+/-0.2)E20 cm**-2, in excess with respect to the galactic value of 1.94E20 cm**-2 (Kalberla et al. 2005). The observed (unabsorbed) flux is 1.7 (2.2)E-11 erg cm**-2 s**-1. The count-rate-to-flux conversion factor is (4.3+/-0.1)E-11. All quoted errors are at 90% confidence level. This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 8625 SUBJECT: Radio detection of GRB 081203B with the VLA DATE: 08/12/05 21:12:08 GMT FROM: Poonam Chandra at U Virginia/NRAO Poonam Chandra (RMC) and Dale A. Frail (NRAO) report on behalf of the Caltech-NRAO-Carnegie GRB Collaboration: "We used the Very Large Array to observe the field of view toward optically bright GRB 081203B (GCN 8600) at a frequency of 8.46 GHz on 2008 Dec 05.70 UT. We detect a radio afterglow at the optical afterglow position quoted by Andreev et al (GCN 8608). The peak radio flux at this position is 160 +/- 41 uJy. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc." //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 8626 SUBJECT: GRB081203B: optical observations DATE: 08/12/05 21:53:05 GMT FROM: Alexei Pozanenko at IKI, Moscow M. Andreev, A. Sergeev, (Terskol Branch of Institute of Astronomy), Ju. Babina (CrAO) A. Pozanenko (IKI) on behalf of larger GRB follow up collaboration report: We are continuing observation (Andreev et al, GCN 8608) of the GRB081203B (Copeteet et al, GCN 8600) with the Z-600 telescope of Mt. Terskol observatory. A set of R-band exposures was taken between Dec.05 (UT) 02:33-03:19. In a combined image of 30x90 s at mid time Dec. 05 (UT) 02:56 we still detect afterglow of the GRB081203B (Schady et al, GCN 8606). A photometry of the afterglow is 20.9 +/- 0.3. The photometry is based on USNO-A2.0 star 1275_08617401 (RA 15 15 10.21 Dec: +44 26 01.4) assuming R=17.1. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 8631 SUBJECT: GRB 081203B: Gemini observations DATE: 08/12/07 12:10:52 GMT FROM: Daniel Perley at U.C. Berkeley D. A. Perley and J. S. Bloom (UC Berkeley) report: We triggered Gemini-N (GMOS) observations of BATSS GRB 081203B (Copete et al., GCN 8600, 8602) starting at 15:04 UT 2008-12-06 through very high airmass but under good conditions. In our acquisition image we identify a source at the position of the optical afterglow (Schady et al., GCN 8606). Photometry, calibrated to SDSS, is: r = 21.90 +/- 0.06 (t = 3.05 days) Two spectroscopic integrations of 1200s each were acquired using the R150 grating. Preliminary inspection of the frames reveals no obvious line features between 5200-9000 A. Further analysis is continuing. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 8637 SUBJECT: GRB 081203B: Additional Gemini imaging DATE: 08/12/08 05:07:27 GMT FROM: Daniel Perley at U.C. Berkeley D. A. Perley (UC Berkeley) reports on behalf of a larger collaboration: During morning twilight on 2008-12-07 UT (starting at 15:40) we undertook additional imaging of the optical transient associated with GRB 081203B, using GMOS on Gemini-North. We report the following magnitudes: g = 22.67 +/- 0.11 (t = 4.076 day) r = 22.41 +/- 0.10 (t = 4.079 day) i = 22.16 +/- 0.20 (t = 4.082 day) Assuming a burst time of 13:52:02 UT (GCN 8600). The SED is well-fit by a power-law with beta = 1.0 +/- 0.3. The power-law index of the light curve compared with our r-band measurement the previous night (GCN 8631) is alpha = 1.6 +/- 0.3. Both values are consistent with typical late-time GRB afterglow behavior. We thank the Gemini staff for conducting these observations, which were carried out under program GN-2008B-Q-6. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 8638 SUBJECT: GRB 081203B: Suzaku WAM observation of the prompt emission DATE: 08/12/08 08:18:54 GMT FROM: Masanori Ohno at ISAS/JAXA Y.Terada, M. Tashiro, Y. Urata, A. Endo, K. Onda, N. Kodaka, K. Morigami, T. Sugasahara, W. Iwakiri (Saitama U.), S. Sugita, K. Yamaoka (Aoyama Gakuin U.), M. Ohno, M. Kokubun, M. Suzuki, T. Takahashi (ISAS/JAXA), Y.E. Nakagawa, T. Tamagawa (RIKEN), T. Enoto, K. Nakazawa, K. Makishima (Univ. of Tokyo), T. Uehara, T. Takahashi, Y. Fukazawa, C. Kira, Y. Hanabata (Hiroshima U.), E. Sonoda, M. Yamauchi, H. Tanaka, R. Hara, N. Ohmori, K. Kono, H.Hayashi, (Univ. of Miyazaki),S. Hong (Nihon U.), on behalf of the Suzaku WAM team, report: The long GRB 081203B (Swift/BAT Slew Survey, Copete et al., GCN Circ. 8600, 8602) triggered the Suzaku Wide-band All-sky Monitor (WAM) which covers an energy range of 50 keV - 5 MeV at 2008-12-03 13:51:31.94713598 UT (=T0). The observed light curve shows a multi-peaked structure starting at T0-0.5s, ending at T0+64s with a duration (T90) of about 45 seconds. The fluence in 100 - 1000 keV was 2.9 x 10^-5 erg/cm^2. The 1-s peak flux measured from T0+11.25s was 2.9 photons/cm^2/s in the same energy range. Preliminary result shows that the time-averaged spectrum from T0-3s to T0+64s is well fitted by a power-law with exponential cutoff model: dN/dE ~ E^{-alpha} * exp(-(2-alpha)*E/Epeak) with alpha 1.2 -0.2 +0.3 and Epeak 304 -20 +22 keV (chi^2/d.o.f. = 50.6/28). All the quoted errors are at statistical 90% confidence level, in which the systematic uncertainties are not included. The light curves for this burst are available at: http://www.astro.isas.jaxa.jp/suzaku/HXD-WAM/WAM-GRB/grb/trig/grb_table.html //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 8651 SUBJECT: GRB081203B: optical observations DATE: 08/12/11 05:43:29 GMT FROM: Vladimir Sokolov at SAO RAS T.A. Fatkhullin (SAO RAS, Niznij Arkhyz), E. Sonbas (SAO RAS, Niznij Arkhyz; University of Cukurova, Turkey), A.J. Castro-Tirado (IAA-CSIC Granada) & A.Pozanenko (IKI RAS, Moscow) on behalf of larger collaboration, report: We observed the field of the GRB081203B (P. Schady et al., GCN 8606; Andreev et al, GCN 8608) in the Rc-band with the 6-m telescope of the SAO RAS in Caucasus. In total two 3-min exposures were obtained. The optical transient (OT) is clearly detected in the both images. Using 4 USNO B1.0 stars we estimated the brightness of the OT as R = 21.81 +/- 0.10 at the epoch of T-T0 = 3.534 days. We assumed a burst time of 13:52:02 UT (Copete et al., GCN 8600). Combining our data with ones from the GCN 8608, 8626, 8631 and 8637 we estimate the observed power-law index of the light curve as alpha ~ 1.0. In the same night we also obtained 2x600sec spectrum of the object near morning twilight. The VPHG550G grism was used with spectral resolution of FWHM=10A. Inspection of the integrated spectrum showed no strong emission lines in the range of 4000-7500AA. The 3-min R-band image can be downloaded from ftp://ftp.sao.ru/pub/grb/GRB081203B/GRB081203B_R01.jpg This message can be cited [GCN OPS NOTE(13dec08): Per author's request, the ftp url was corrected.]