//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11386 SUBJECT: GRB 101030A: Swift detection of a burst DATE: 10/10/30 16:13:55 GMT FROM: David Palmer at LANL A. Melandri (INAF-OAB), S. D. Barthelmy (GSFC), M. M. Chester (PSU), V. D'Elia (ASDC), J. M. Gelbord (PSU), C. Guidorzi (U Ferrara), S. T. Holland (CRESST/USRA/GSFC), E. A. Hoversten (PSU), J. A. Kennea (PSU), H. A. Krimm (CRESST/GSFC/USRA), R. Margutti (INAF-OAB), F. E. Marshall (NASA/GSFC), K. L. Page (U Leicester), D. M. Palmer (LANL), M. H. Siegel (PSU) and E. Troja (NASA/GSFC/ORAU) report on behalf of the Swift Team: At 15:56:29 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 101030A (trigger=437408). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 166.390, -16.387 which is RA(J2000) = 11h 05m 34s Dec(J2000) = -16d 23' 11" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve shows that the burst began with a bright peak starting at around -70 sec from the trigger, followed by a second episode starting at T-10 sec and consisting of two overlapping peaks with a duration of about 80 sec. We note that the first peak occurred during a pre-planned slew, so the BAT could not trigger on it; it is also possible that BAT missed emission from the burst before T-100 sec. The peak count rate was ~2000 counts/sec (15-350 keV), at ~0 sec after the trigger. The XRT began observing the field at 15:57:35.6 UT, 65.7 seconds after the BAT trigger. Using promptly downlinked data we find a bright, fading, uncatalogued X-ray source with an enhanced position: RA, Dec 166.3825, -16.3782 which is equivalent to: RA(J2000) = 11h 05m 31.80s Dec(J2000) = -16d 22' 41.5" with an uncertainty of 2.5 arcseconds (radius, 90% containment). This location is 40 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 4.24 x 10^20 cm^-2 (Kalberla et al. 2005). The initial flux in the 2.5 s image was 2.81e-09 erg cm^-2 s^-1 (0.2-10 keV). UVOT took a finding chart exposure of 150 seconds with the White filter starting 73 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 100% of the XRT error circle. The typical 3-sigma upper limit has been about 19.6 mag. 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 0.04. Burst Advocate for this burst is A. Melandri (andrea.melandri AT brera.inaf.it). 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: 11387 SUBJECT: GRB 101030A: Enhanced Swift-XRT position DATE: 10/10/30 18:30:41 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 807 s of XRT Photon Counting mode data and 1 UVOT images for GRB 101030A, 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 = 166.38198, -16.37812 which is equivalent to: RA (J2000): 11h 05m 31.68s Dec (J2000): -16d 22' 41.2" with an uncertainty of 1.9 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: 11388 SUBJECT: GRB 101030A: Swift-BAT refined analysis DATE: 10/10/30 19:16:54 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), C. B. Markwardt (GSFC), A. Melandri (INAF-OAB), D. M. Palmer (LANL), T. Sakamoto (GSFC/UMBC), M. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (GWU) (i.e. the Swift-BAT team): Using the data set from T-60 to T+243 sec from the recent telemetry downlink, we report further analysis of BAT GRB 101030A (trigger #437408) (Melandri, et al., GCN Circ. 11386). The BAT ground-calculated position is RA, Dec = 166.390, -16.389 deg, which is RA(J2000) = 11h 05m 33.6s Dec(J2000) = -16d 23' 22.0" with an uncertainty of 1.1 arcmin, (radius, sys+stat, 90% containment). The partial coding was 96%. The mask-weighted light curve shows the burst already in progress as it came into the BAT FoV at ~T-60 sec during a pre-planned slew. The lightcurve decreases from that time and nearly returns to background levels at ~T-18 sec. Then it begins to rise again, peaking at T+1 sec and ~T+9 sec and returning to background at ~T+70 sec. There is possible emission at the 2-sigma level from T+130 sec to T+170 sec. T90 (15-350 keV) is 92.0 +- 50 sec (estimated error including systematics). The time-averaged spectrum from T-55.2 to T+47.8 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.82 +- 0.10. The fluence in the 15-150 keV band is 2.0 +- 0.1 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+8.78 sec in the 15-150 keV band is 0.9 +- 0.1 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/437408/BA/ //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11389 SUBJECT: GRB 101030A: Swift/UVOT Upper Limits DATE: 10/10/31 04:17:28 GMT FROM: Erik Hoversten at Swift/Penn State E. A. Hoversten (PSU) and A. Melandri (INAF-OAB) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 101030A 73s after the BAT trigger (Melandi et al., GCN 11386). We do not detect any source at the enhanced Swift XRT position (Evans et al., GCN 11387). UVOT magnitude 3-sigma upper limits are reported in the following table: Filter T_start T_stop Exp(s) Mag (3-sigma upper limit) ------------------------------------------------------------- white(fc) 73 223 146 > 20.32 white 73 1008 327 > 20.75 v 617 808 38 > 17.89 b 542 735 38 > 18.83 u 285 710 260 > 19.68 uvw1 666 857 38 > 18.39 uvm2 641 833 38 > 18.18 uvw2 592 784 38 > 18.61 The quoted upper limits have not been corrected for the expected Galactic extinction along the line of sight of E_(B-V) = 0.04 (Schlegel et al. 1998). All photometry is on the UVOT photometric system described in Poole et al. (2008, MNRAS, 383, 627). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11390 SUBJECT: GRB 101030A : Swift XRT refined analysis DATE: 10/10/31 13:47:52 GMT FROM: Andrea Melandri at Liverpool John Moores U A. Melandri, R. Margutti and B. Sbarufatti (INAF-OAB) report on behalf of the Swift-XRT team: We have analysed 7.4 ks of XRT data for GRB 101030A (Melandri et al. GCN Circ. 11386), from 71 s to 19.2 ks after the BAT trigger. The data comprise 118 s in Windowed Timing (WT) mode with the remainder in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Evans et al. (GCN. Circ 11387). The light curve can be modelled with a series of power-law decays. The initial decay index is alpha=2.32 (+0.26, -0.33). At T+112 s the decay steepens to an alpha of 3.97 (+0.24, -0.22). The light curve breaks again at T+478 s to a decay with alpha=-0.08 (+0.18, -1.43), before a final break at T+5105 s after which the decay index is 1.12 (+0.22, -0.21). A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 2.87 (+0.15, -0.13). The best-fitting absorption column is 1.83 (+0.26, -0.24) x 10^21 cm^-2, in excess of the Galactic value of 4.2 x 10^20 cm^-2 (Kalberla et al. 2005). The PC mode spectrum has a photon index of 2.11 (+0.12, -0.20) and a best-fitting absorption column of 8.1 (+2.7, -3.9) x 10^20 cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.6 x 10^-11 (4.6 x 10^-11) erg cm^-2 count^-1. If the light curve continues to decay with a power-law decay index of 1.12, the count rate at T+24 hours will be 4.7 x 10^-3 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.7 x 10^-13 (2.2 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/00437408. This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11391 SUBJECT: GRB 101030A: GROND optical/NIR afterglow candidate DATE: 10/10/31 19:43:07 GMT FROM: Thomas Kruehler at MPE/MPI T. Kruehler, P. Schady, and J. Greiner (all MPE Garching) report on behalf of the GROND team: GROND (Greiner et al. 2008, PASP 120, 405), mounted at the 2.2m MPG/ESO telescope at LaSilla Observatory (Chile), performed automated follow-up observations of GRB 101030A (Melandri et al., GCN #11386) as soon as the field rose above the pointing constraints of the telescope. Imaging was performed simultaneously in g'r'i'z'JHK starting at 08:12 UT on 2010-10-31, which is 16.3 h after the burst. Inside the enhanced XRT error circle (Evans et al., GCN# 11387), GROND detects a single object at: RA (J2000)= 11:05:31.68 Dec (J2000)= -16:22:41.1 with uncertainties of 0.3" in each coordinate. Preliminary AB magnitudes and upper limits in stacked images of 15 min integration time in each g'r'i'z' and 20 min in JHK at a midtime of 08:46 UT are: g' = 22.9 +- 0.3 r' = 22.4 +- 0.1 i' = 22.0 +- 0.1 z' = 22.1 +- 0.2 J = 21.7 +- 0.4 H > 21.2 K > 20.5 which have been tied to SDSS and 2MASS field stars. No statement about variability can be made at this point. No source is reported at this location in the SDSS, which is somewhat deeper than the object's magnitudes, and hence we suggest this source is the optical/NIR afterglow of GRB101030A. We thank the ESO staff at LaSilla observatory, and in particular P. Arias, for their excellent support and assistance with the observations. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11392 SUBJECT: GRB 101030A : MOA optical observation DATE: 10/11/06 18:06:59 GMT FROM: Suzuki Daisuke at MOA-II D. Suzuki, K. Omori, S. Kobara, H. Naito and T. Sako (STE Lab, Nagoya Univ.) on behalf of the MOA Collaboration report: We searched for an optical afterglow of GRB101030A (GCN 11386, Melandri et al.) starting from 15:59:39 UT on 2010 Oct. 30th with the MOA-II 1.8m telescope at Mt.John observatory in New Zealand. The images were taken with a wideband Red filter (center wavelength ~ 750nm and FWHM ~ 250nm), and we found a new source within the error circle of the Swift XRT source position (GCN 11387). The estimated magnitudes are the followings. t-t0(sec) Imag err exp. ------------------------- 190 20.0 2.3 300 610 19.5 4.0 100 ------------------------- Large errors in the magnitude estimation are due to the observations during dawn and under the moon light. Consequently, relatively small number of field stars affects in the large errors. These magnitudes were calibrated against the USNO-B1.0 catalog stars, and not corrected for the Galactic extinction. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11435 SUBJECT: GRB101030A DATE: 10/12/02 21:20:39 GMT FROM: Valentyna Golovnya at Main Astro Obs,Kyiv GRB 101030A, the review of the sky area in plate archives V.V. Golovnya, L.K. Pakuliak (Main Astro Obs, Kyiv) report: We have undertaken the review of the sky area of GRB 101030A (Evans et al., GCN 11387) on astronegatives, collected in Ukrainian NAS Main astronomical observatory plate archive (1976-1996). All the plates with the possible object appearance are digitized using Microtek ScanMaker 9800XL TMA flatbed scanner and have been placed into Golosiiv Plate Archive database DBGPA with open access to them. The list of plates is given in the table: YYYYMMDD UT Plates/Films Exp. LimMag 19860501 19:23:22 GUA040C002903 30.0 12.25 19860501 19:23:27 GUA040D002904 11.9 13.15 19860503 00:29:45 QUI021B000206 10.1 12.15 19860503 00:48:10 QUI021B000208 10.1 12.15 Plates/Films: GUA040C –the plates archive identifier of DWA (D/F=400/2000,M=103"/mm) GUA040D of the Ukrainian NAS Main astronomical observatory in Kyiv (Marsden's number - 83) the plate number [1]. QUI021B -the films archive identifier of AFU-75 (D/F=210/740,M=280"/mm) of the Quito Astro. Obs. in Ecuador (Marsden's number - 781) the plate number [1]. Exp. - Duration of the maximum exposures (minutes). LimMag - Limited mag, derived in the 50 minutes area around the location given in Evans et al., GCN 11387: RA (J2000): 11h 05m 31.68s, Dec (J2000): -16d 22' 41.2". The preview images of 4 areas together with the 8 min.of arc area from SkyMap can be found in http://gua.db.ukr-vo.org/img/grb/101030A/index. The images with full resolution are available via e-mail on demand. References: 1.L.Pakuliak DATABASE of GOLOSIIV PLATE ARCHIVE (DBGPA V2.0), http://gua.db.ukr-vo.org/