//////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1118 SUBJECT: BeppoSAX ALERT: Possible X-ray rich GRB011030 DATE: 01/10/30 13:23:12 GMT FROM: Giangiacomo Gandolfi at IAS/CNR Frascati BeppoSAX ALERT: Possible X-ray rich GRB011030 On Oct. 30, 06:28:02 U.T. a faint transient has been detected by the WFC1 aboard BeppoSAX, without counterpart in the GRBM. Preliminary coordinates from WFC are: R.A.(2000)= 310.927 DEC.(2000)= 77.293 The error radius at this stage of analysis is 5'. A preliminary analysis of quick-look data shows that the event could be an X-ray rich GRB, but the low galactic latitude and the presence of a faint Rosat source (1RXS J204310.8+77172) inside the error box can not exclude the x-ray burster nature of the source. We are not planning a follow-up observation of this burst, due to the on-going testing phase of gyroless attitude control system. Giangiacomo Gandolfi on behalf of BeppoSAX Mission Scientist [GCN OPS NOTE: This distribution was delayed by about 1.5 hours because the original submission address was invalid. Apologies for the delay.] [GCN OPS NOTE: Due to confusion about active submitors accounts and delays in the distributions, this was submitted twice and distributed twice. The second copy (originally numbered 1119) was deleted from the archive and the serial number sequence set back to waiting for the next submission.] //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1119 SUBJECT: X-ray rich GRB011030: BeppoSAX refined positions DATE: 01/10/30 15:48:21 GMT FROM: Giangiacomo Gandolfi at IAS/CNR Frascati X-ray rich GRB011030: BeppoSAX refined positions Refined coordinates from WFC are: R.A.(2000) = 310.911 DEC.(2000) = 77.292 The error radius is 3'. Giangiacomo Gandolfi on behalf of BeppoSAX Mission Scientist //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1120 SUBJECT: GRB 011030, R-band observations DATE: 01/10/30 21:00:19 GMT FROM: Alberto Castro-Tirado at Inst.de Astro. de Andalucia GRB 011030, R-band observations -------------------------------- Vijay Mohan, S.B. Pandey, J.C. Pandey, Yogesh Joshi, Ram Sagar, UPSO (Nainital) Michel Creze (Univ. of Bretagne Sud) Alberto J. Castro-Tirado, IAA-CSIC (Granada) José María Castro Cerón, ROA (San Fernando) Jochen Greiner, AIP (Potsdam) Sylvio Klose, TLS (Tautenburg) Juergen Fliri, USM (Munich) report: "We have just obtained several R-band exposures centred at the GRB 011030 error box (Gandolfi et al. GCN#1119) starting at 13:40 UT on 30 Oct 2001 with the 1.0-m telescope at Nainital (India) and at 18:05 UT at the 1.23-m telescope at the German-Spanish Calar Alto Observatory (CAHA). A preliminary analysis of the images reveal no optical counterpart within a 5' radius down to R = 21 when comparing with the DSS-2 R-band chart. Further R- and I-band observations are in progress." //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1121 SUBJECT: GRB011030: radio search DATE: 01/10/31 12:20:21 GMT FROM: Guy Pooley at MRAO, Cambridge, UK Radio search for GRB011030 The Ryle Telescope (Cambridge, UK) was used for a 3-hour observation centred on the refined position of GRB011030 (GCN 1119), from 21:15 UT on 2001 Oct 30. The field covered is 6' fwhm, resolution about 30", observing frequency 15 GHz. No source was detected, to a noise level 0.4 mJy rms. Guy Pooley (MRAO, Cambridge) //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1122 SUBJECT: GRB 011030, Radio observations DATE: 01/10/31 23:07:34 GMT FROM: Greg Taylor at NRAO G. B. Taylor, D. A. Frail (NRAO), and D. Fox (Caltech) report on behalf of a larger collaboration: "We have imaged the entire 3 arcmin WFC error circle of GRB 011030 (GCN 1118) with the VLA at 8.47 GHz on UT 2001 Oct. 31.13. We detect two radio sources which we designate VLA J2042+7718 and VLA J2044+7717. The coordinates of VLA J2042+7718 are RA = 20h42m46.09s, DEC = 77d18'22.2" (J2000) and VLA J2044+7717 are RA = 20h44m07.61s, DEC = 77d17'37.4" (J2000) with conservative errors of 1 arcsec in each coordinate. VLA J2044+7717 is well within the WFC error circle while VLA J2042+7718 is right on the edge of the error circle. Preliminary flux densities are 0.9 mJy for VLA J2042+7718 and 0.3 mJy for VLA J2044+7717. Neither source is detected in the NRAO VLA Sky Survey (NVSS; Condon et al. 1998, AJ, 115, 1693) above their flux limit of 1 mJy at 1.4 GHz. We have searched the DSS and find a faint galaxy near VLA J2044+7717. We encourage observers at other wavebands to check for counterparts at the positions of these two radio sources. Further radio observations are planned." This message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1123 SUBJECT: GRB011030 - further refinement WFC position DATE: 01/11/01 12:23:04 GMT FROM: Jean int Zand at SRON J.J.M. in 't Zand, J. Heise (SRON, Utrecht), P. Lowes (SOC, Telespazio, Rome, and SRON), G. Gandolfi, L. Piro, E. Costa (IAS, CNR, Rome), report: "We have been able to further refine the position of GRB 011030 as obtained with the Wide Field Camera unit 1 on BeppoSAX (GCN Circ. 1118, 1119). The final result is R.A. = 20h43m35.4s, Decl. = +77d17m20s (J2000.0) with an error radius of 2.1 arcmin (99% confidence). We note that VLA J2044+7717 is at 1.8 arcmin from this WFC centroid and VLA J2042+7718 at 2.9 arcmin. Therefore, the latter radio source is ruled out as counterpart to GRB 011030 by this refinement. The WFC observation was performed during the testing phase of the new gyro-less pointing mode. A preliminary analysis of all data collected so far shows that the pointing accuracy in the gyro-less pointing mode is consistent with or better than that during the one-gyro mode." //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1124 SUBJECT: GRB 011030, WSRT radio observations DATE: 01/11/01 17:11:12 GMT FROM: Evert Rol at U.Amsterdam Evert Rol, Paul Vreeswijk, Isabel Salamanca, Lex Kaper (University of Amsterdam), Ralph Wijers (SUNY Stony Brook), Richard Strom (UoA, ASTRON), Tony Foley (ASTRON) report, on behalf a larger collaboration: We have observed the error box of the possible GRB 011030 (Gandolfi, GCN 1118, 1119) at 4.8 GHz with the Westerbork Synthesis Radio Telescope. We detect the two VLA sources found by Taylor et al. (GCN 1122). Within the refined error circle (In't Zand, GCN 1123), we find only one source, VLA J2044+7717. Our observations show this source to be constant at 4.8 GHz, with a spectral index of 0.6 between our 4.8 GHz flux and the VLA 8.6 GHz measurement: flux (mJy) freq date 0.23 +- 0.04 4.8 GHz Oct 30.68 0.20 +- 0.04 4.8 GHz Oct 31.71 Further observations are planned to see whether this source is the counterpart to GRB 011030. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1126 SUBJECT: GRB 011030 K-band Observations DATE: 01/11/01 18:23:02 GMT FROM: Jules Halpern at Columbia U. Molly Hammell (Dartmouth), J. P. Halpern, & N. Mirabal (Columbia U.) report on behalf of the MDM Observatory GRB follow-up team: "Using the MDM 1.3m, we obtained 120 minutes of exposure in the K band centered at Oct. 31.11 UT, 20 hours after the burst. All of the 2.1' radius refined BeppoSAX error circle (in 't Zand et al., GCN #1123) was covered. A follow-up observation was performed on Nov. 1.20 UT, with 40 minutes of exposure. Conditions were not photometric, and these images have not been calibrated. However, no afterglow candidate has been found to an approximate limiting magnitude K > 18. Additional observations on Nov. 1 covering the position of the radio source VLA J2042+771 reported by Taylor et al. (GCN #1122) reveal no detection to a slightly deeper limiting magnitude. A prominent galaxy is seen at the position of the radio source VLA J2044+7717 (see also Rol et al., GCN #1124). It is constant to better than 0.05 mag. I-band images were also obtained on both nights using the MDM 2.4m. Results of these will be reported subsequently. A K-band image is posted at http://www.astro.columbia.edu/~jules/grb/011030 This message may be cited." //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1127 SUBJECT: GRB 011030 I-band Observations DATE: 01/11/02 20:57:19 GMT FROM: Jules Halpern at Columbia U. J. P. Halpern, N. Mirabal (Columbia), Chris Burke, & D. L. DePoy (Ohio State), report on behalf of the MDM Observatory GRB follow-up team: "Using the MDM 2.4m, we obtained 15 minutes of exposure in the I band centered at Oct. 31.21 UT, 22.5 hours after the burst. All of the 2.1' radius refined BeppoSAX error circle (in 't Zand et al., GCN #1123) was covered. A follow-up observation was performed on Nov. 1.22 UT, with 15 minutes of exposure. Conditions were not photometric, and these images have not been calibrated. However, no afterglow candidate has been found to a limit approximately 1 mag fainter than the POSS-II IVN plate, or I_c > 20.5. An I-band image is posted at http://www.astro.columbia.edu/~jules/grb/011030 This message may be cited." //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1136 SUBJECT: The Radio Afterglow from the X-ray Rich GRB 011030 DATE: 01/11/09 05:08:47 GMT FROM: Greg Taylor at NRAO G. B. Taylor (NRAO), D. A. Frail (NRAO/Caltech) and S. R. Kulkarni (Caltech) report on behalf of the Caltech-NRAO-CARA collaboration: "We have continued to monitor the WFC error circle of the X-ray transient 011030 (GCN 1119, 1123) with the VLA at 8.47 GHz. Observations were made over four epochs on Oct. 31.13, Nov. 1.79, Nov. 4.81, and Nov 8.80 UT. Over this period the radio source VLA J2044+7717 (GCN 1122) has remained constant, in agreement with the 4.8 GHz observations by Rol et al. (GCN 1124). On 2001 Nov 8.80 UT a new source was detected with high significance with a flux density of 181 +/- 18 microJy. This new source is located near the center of the WFC error circle at (epoch 2000) R.A.=20:43:32.3, Dec.=+77:17:18.9, with a conservative error of +/-1 arcsec in both coordinates. Little is known about the class of such X-ray rich transients. This is the first detection of a counterpart at any other wavelength to an X-ray rich transient. We will continue further radio observations and urge observations at other wavelengths." This message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1137 SUBJECT: Non-triggered burst 011030 ("GRB 011030") DATE: 01/11/09 14:23:23 GMT FROM: Shri Kulkarni at Caltech J. S. Bloom, A. Gil de Paz, F. A. Harrison and S. R. Kulkarni (Caltech) report: "Optical imaging observations were carried out at the Palomar 60-inch telescope on 9 November, 2001 (UT) by Armando Gil de Paz. Six images of 600 s duration were observed under non-photometric conditions. We found no optical counterpart to a limiting magnitude of R=22.9 magnitude (5 sigma). Our photometry is based on assuming R=17.3 for the USNO A2.0 star 6-arcsecond to the northeast of the radio position. The astrometry is with respect to more than 200 USNO A2.0 stars and the overall astrometric accuracy is about 0.25 arcseconds (in each coordinate). We also note that the Galactic extinction towards this direction is high (A_R about 1 magnitude)." //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1138 SUBJECT: The X-ray Flash 011030 ('GRB 011030') DATE: 01/11/09 16:25:10 GMT FROM: Jean int Zand at SRON J. Heise (SRON, Utrecht), J.J.M. in 't Zand (Utrecht Univ. and SRON), S.R. Kulkarni (Caltech), and E. Costa (CNR, IAS, Rome) report: "We have carried out further investigations of SAX J2043.6+7717, the X-ray rich transient of 30 October, 2001 discovered by BeppoSAX-WFC (GCN 1118). The flash peaks at 0.26 Crab units (2-28 keV), while activity is detected for about 1400 s (but we note that the observations started about 100 s before the first activity from this source was detected). The spectrum is characterized by a power law with a photon index of -1.9 +/- 0.1. A black body fit is inconsistent with the data at 99.97% confidence. The 2-28 keV fluence is estimated at 9E-7 erg/cm2. For X-ray light curve and spectrum, we refer to http://wfc.sron.nl/flash/ What could SAX J2043.6+7717 be? By several accounts, SAX J2043.6+7717 does not appear to be a traditional GRB. First, the absence of detection of the X-ray transient in the Gamma-Ray Burst Monitor on BeppoSAX means that the peak energy of the transient must be lower than ~40 keV. In contrast, GRBs are distinguished by peaking in the 50 to 500 keV range. Second, GRBs with such long duration are rare, e.g. the longest T90 listed in the 4th BATSE catalog (Paciesas et al. 2000, ApJS, 122, 465) out of 1234 bursts is 674 s (trigger 3458) and in general have strong pulses. In contrast, SAX J2043.6+7717 lasted more than a thousand seconds long. The second possibility, especially given the galactic latitude of SAX J2043.6+7717 (b=+20.7 degrees), may argue for this source to be a Galactic transient. However, the X-ray spectrum rules out SAX J2043.6+7717 being a type I X-ray burst. This then leaves us with the possibility that SAX J2043.6+7717 is a Fast X-ray Transient (FXT; e.g., Grindlay 1999, ApJ, 510, 710). However, FXTs usually last longer than an hour. More importantly, FXTs have been identified with relatively bright quiescent optical/IR counterparts e.g. RS CVns, nearby dMe stars, super flares from pre-main sequence stars and black hole transients. However, as noted in GCN 1137, there is no visible optical counterpart to the radio source nor was a bright optical or IR transient (GCN 1127) seen following the detection of the X-ray transient. We conclude that most likely SAX J2043.6+7717 is a member of the newly recognized class of X-ray flashes (Heise et al. 2001, in Proc. 'Gamma-Ray Burst in the Afterglow Era', Rome, Oct. 17-20, 2000, in press). Given that we know little about such events (with the 011030 flash possibly being the first event localized to arcsecond accuracy; see GCN 1136) it is not appropriate to call such non-triggered transients as "X-ray rich, gamma-ray poor" GRBs (or other equally oxymoronic names). Recognizing that astronomical research is largely based on empiricism, we suggest that events such as the one on 011030 characterized by the following criterion be termed as "X-ray flashes" (XRF): (1) Strong non-thermal emission in the X-ray (2-20 keV band; this criterion distinguishes them from type I bursts); (2) Weak in the traditional GRB gamma-ray band, 50-250 keV; this explains why typical XRFs do not trigger gamma-ray burst monitors. (3) Durations less than a few thousand seconds; this differentiates XRFs from the so-called fast X-ray transients which have durations of several hours (many of which are stars with intense coronal activity and some are binaries containing a compact object such as XTE J1819-254). (4) Display no strong quiescent optical/IR counterpart; this criterion distinguishes XRFs from stars with strong coronal activity (e.g. strong flares from pre-main sequence stars, dMe stars, RSCVn stars, Be stars etc). The accurate position of this X-ray flash presents an excellent opportunity to understand this new phenomenon which previously has never been detected outside the X/gamma-ray regime. We strongly encourage multi-wavelength observations." This message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1139 SUBJECT: GRB 011030 I-band Observation DATE: 01/11/09 19:29:34 GMT FROM: Jules Halpern at Columbia U. J. P. Halpern, N. Mirabal (Columbia), C. Burke, D. L. DePoy (Ohio State), & S. Gaudi (IAS), report on behalf of the MDM Observatory GRB follow-up team: "Using the MDM 2.4m, we reobserved this location in the I band on Nov. 9.23 UT. In two 8 minute exposures in seeing of 1.2 arcseconds, there is a possible detection at the 2 sigma level of an object at position (J2000) 20:43:31.94, +77:17:19.0, which is 1.2 arcseconds west of the position reported for the new radio source that appeared on Nov 8.80 (Taylor et al. GCN #1136). Assuming for a calibration that the faintest objects on the POSS-II IVN plates have I=19.5, this possible counterpart would have I=22.5. Given the marginal level of this detection and its absence on previous images of comparable depth on Nov. 1, confirmation would be required. Alternatively, this may be considered an upper limit to the optical brightness of the radio source. The new image is posted at http://www.astro.columbia.edu/~jules/grb/011030 This message may be cited." //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1140 SUBJECT: GRB 011030 R band observations DATE: 01/11/10 02:36:39 GMT FROM: James Rhoads at STScI James E. Rhoads, Ingunn Burud, Andrew Fruchter, Chryssa Kouveliotou, and Michael Wood-Vasey report on behalf of a larger collaboration: We observed the error circle of GRB 011030 with the 3.5m WIYN telescope and mini-mosaic imager on the nights of UT 011101, 011102, and 011103, obtaining five 600 second images in the R band each night. We find no source at the location of the new radio source reported by Taylor et al (GCNC 1136). If we adopt the R band zero point used by Bloom et al (GCNC 1137), the corresponding 5 sigma upper limits are R=23.61 (011101) and R=23.28 (011103). In addition, we performed a seeing-matched image subtraction on the 011101 and 011103 data. The difference image shows no significantly variable sources. The estimated photometric noise level in the difference image (for a 1 arcsec radius aperture) is 0.5 microJansky (1 sigma), corresponding to R=24.5 (1 sigma) or R=22.7 (5 sigma). Further analysis of existing data is underway, and at least one additional observation is planned. We thank Doug Williams and Di Harmer for their help in these observations. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1141 SUBJECT: GRB011030: Z-band observations DATE: 01/11/14 23:12:28 GMT FROM: Andrew S. Fruchter at STScI M. Brown, A. Dey (NOAO), A. Fruchter and J. Rhoads (STScI) report for a larger collaboration: The field of the radio transient (Taylor et al., GCN 1136) potentially associated with GRB011030 was imaged at the KPNO 4-m using the Multi-Aperture Red Spectrometer (MARS) through an RG830 (approximately z-band) filter from 1:55 to 2:50 12 NOV 01 UT. Due to significant overhead associated with the instrument, the total exposure time was 600 seconds; the seeing was approximately 1."5. No source was detected at the position of the radio transient, or that of the potential I-band object nearby reported by Halpern et al. (GCN 1139), down to a limiting (Vega) magnitude of 22.5 (5-sigma). //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1142 SUBJECT: GRB 011030: K-band observations DATE: 01/11/15 12:27:51 GMT FROM: Sylvio Klose at TLS Tautenburg S. Klose, B. Stecklum, A. Zeh (Thueringer Landessternwarte Tautenburg), O. Fischer (Universitaets-Sternwarte Jena), U. Thiele (Calar Alto observatory, Spain), R. Neuhaeuser, N. Huelamo, (Max-Planck-Institut fuer Extraterrestrische Physik, Garching), J. Greiner (AIP Potsdam), A. Castro-Tirado (LAEFF-INTA, Madrid, and IAA-CSIC, Granada), N. Masetti, E. Palazzi (ITeSRE, CNR, Bologna), E. Pian (Oss. Astron. Trieste), report: The error circle of the X-ray transient 011030 (Gandolfi et al., GCN #1118) was imaged with the Calar Alto 3.5-m telescope on Oct. 30, 18:32 UT - 19:33 UT (i.e., about 12 hours after the burst trigger) using the near-infrared camera Omega Cass in the polarimetric mode. The limiting magnitude in the central part of the K'-band image (mosaic) is about K'=19.5 after adding all frames taken at different position angles of the wire-grid polarizer. Since standard stars are not yet available we estimate the error of this magnitude limit to +/- 0.5 mag. The combined image covers about 90% of the revised error circle (in 't Zand et al., GCN #1123). At the position of the radio transient reported by Taylor et al. (GCN #1136) no source is detected (see also Hammell et al., #GCN 1126). We do not detect the I-band source reported by Halpern et al. (GCN #1139). This message is quotable. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1143 SUBJECT: XRF011030: Chandra Observations DATE: 01/11/18 02:59:44 GMT FROM: Derek Fox at CIT F. A. Harrison, S. Yost, D. Fox, J. Heise, S. R. Kulkarni, P. A. Price, and E. Berger report on behalf of the Caltech-NROA-CARA GRB collaboration: "We obtained a 47 ksec Chandra observation of the field containing the BeppoSAX X-ray transient XRF 011030 (GCN 1118), centered on the radio transient reported by Taylor et al. (GCN 1136). We detect an X-ray source within 1.2'' of the radio transient, at RA 20:43:32.5, DEC +77:17:17.4. The X-ray spectrum over 0.2-5 keV is consistent with a power law of photon index ~1.45, with interstellar absorption levels of N_H ~ 2e21 cm^-2, consistent with the Galactic value along the line of sight. Extrapolating this spectrum to the 2-10 keV band, we derive an unabsorbed flux of 2.4e-13 erg cm^-2 s^-1. This source is not detected in the ROSAT All-Sky Survey and its position is consistent, within the uncertainties, with the VLA position of the radio transient. We therefore associate the X-ray source with the variable radio object. Further monitoring is planned in order to determine its long-term X-ray variability." This message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1144 SUBJECT: GRB011030, optical observation DATE: 01/11/19 14:22:21 GMT FROM: Rene Hudec at AIO R. Hudec (Astronomical Institute Ondrejov), J. Polcar (Astronomical Institute Ondrejov and Masaryk University Brno), M. Tichy and J. Ticha (Klet Observatory) report: The whole error box of GRB011030 was imaged with the Klet Observatory 0.57-meter f/5.2 telescope (+CCD camera SBIG ST-8) on 2001 Oct 31, 17:24 to 17:39 UT (10 exposures 60 sec each). No new and/or fading object has been detected down to limiting magnitude of 19.5 (unfiltered), error 0.5 mag. This message can be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1145 SUBJECT: XRF011030: J and K band observations DATE: 01/11/21 14:25:54 GMT FROM: Elena Pian at ITESRE-CNR,Bologna F. Mannucci (CAISMI, CNR, Firenze), V. Calamai (INAF, Oss. Astrofisico di Arcetri), E. Palazzi, N. Masetti (ITeSRE, CNR, Bologna), E. Pian (INAF, Astr. Obs. Trieste), P. Saracco (INAF, Astr. Obs. Brera), A. Antonelli (INAF, Astr. Obs. Rome), on behalf of a larger collaboration, report: We imaged the field of XRF011030 (GCN 1118) with TIRGO equipped with the near-IR camera ARNICA and the J and K filters on Oct 30, 18:15 - 21:22 UT. The PSF FWHM was about 2.0". A standard star for flux calibration is available in the K band only; the J band image was calibrated instead by using an average zero point. No source is detected at the position of the radio transient reported by Taylor et al. (GCN 1136), nor in the Chandra error box of the X-ray source detected by Harrison et al. (GCN 1143) to 5-sigma limiting magnitudes of J=19.8 and K=18.0. This message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1146 SUBJECT: GRB 011030: TNG K-band observation DATE: 01/11/21 17:03:56 GMT FROM: Angelo Antonelli at Obs. Astro. di Roma L.A. Antonelli, (INAF, Astr. Obs. Rome), F. Mannucci (CAISMI, CNR, Firenze), E. Pian (INAF, Astr. Obs. Trieste), V. Testa, A. Di Paola, L. Stella (INAF, Astr. Obs. Rome), I. Burud, A. Fruchter, J. Rhoads (STScI), N. Masetti, E. Palazzi, F. Frontera (ITeSRE, CNR, Bologna), S. Covino (INAF, Astr. Obs. Brera, Milan), D. Lazzati (IoA, Cambridge), L. Piro (IAS, CNR, Rome), J. Licandro, F. Ghinassi (TNG), S. Klose (TLS, Tautenburg), on behalf of a larger collaboration, report: "We imaged the field of XRF011030 (GCN 1118) with TNG equipped with the near-IR camera NICS and K filter on Nov 10, 20:22 - 22:48 UT. During the observation the seeing was 1.5". The AS36 photometric standard was also observed and used for magnitude calibration. No source is detected at the position of the radio transient reported by Taylor et al. (GCN 1136) nor in the Chandra error box of the X-ray source detected by Harrison et al. (GCN 1143) to a 5-sigma limiting magnitude of K = 20.1. This message may be cited." //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1268 SUBJECT: XRF/GRB 011030: Detection of the Probable Host Galaxy DATE: 02/03/12 20:03:45 GMT FROM: Andrew S. Fruchter at STScI A. Fruchter (STScI), S. Pattel (MSFC), C. Kouveliotou (MSFC), J. Rhoads (STscI), S. Holland (Notre Dame), I. Burud (STScI) and R. Wijers (Stony Brook) report for the larger GOSH (Grb Optical Studies with Hst) collaboration: A field containing the reported X-ray (GCN 1143) and radio (GCN 1136) positions of XRF/GRB 011030 (GCN 1118) was observed with HST on 12 December 2001 using the STIS CCD camera both in open mode (50CCD) and with a red-pass filter (LP). Due to the low-galactic latitute (b=20.6) of this field, the estimated foreground extintion is Av=1.2 (Schlegel, Finkbeiner, Davis 1999). Nevertheless, a 26th magnitude galaxy is found to be coincident with both the X-ray and radio positions (within the reported ~1" errors of both). With the public release of the second epoch of Chandra observations (taken on 29 November 2001), we have been able to determine that the X-ray source fell between the two Chandra epochs approximately as t^{-2} (using the time of the XRF/GRB as the zero-point), thus confirming the association of this source with the XRF/GRB. We have therefore attempted to refine the Chandra error circle. We aligned the first, deeper (9-November) Chandra observation with wide-field R band images obtained on the 1 and 3 November on the WIYN telescope using six point sources which are bright in both images. We find an r.m.s. positional offset between sources in the two images of ~0."18. As the XRF/GRB is brighter in the Chandra image than any source used in the fit (though not visible in the WIYN image), we estimate that the error in transforming its position to the optical field should be no larger than 0."18, one sigma. We have also been able to place the WIYN image on the J2000 coordinate system to an accuracy of ~0."1, using both Naval Observatory and Tycho standards. We find that the 0."18 Chandra error circle overlaps the somewhat bluer, eastern end of the small irregular galaxy noted above. The galaxy is approximately 0."5 across, and has a total magnitude of V~26.2, or approximately V=25, after removal of the estimated foreground extinction. This is comparable to the peak of the distribution of XRF/GRB host magnitudes (Hogg and Fruchter 1999). The color of the galaxy (again after removal of the foreground extinction) is quite blue (consistent with a power-law of nu^{-0.5}), suggesting both a relatively young stellar population and that the galaxy has a redshift, z < 3. XRF/GRB 011030 thus appears to be similar to GRBs in its probable redshift and in its association with a faint, blue galaxy; this in turn suggests that XRFs are not a radically different class of object, but are very soft GRBs. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1269 SUBJECT: XRF/GRB 011030 Images DATE: 02/03/12 20:37:27 GMT FROM: Andrew S. Fruchter at STScI A. Fruchter (STScI) reports: Images of the probable host galaxy of XRF/GRB 011030, described in GCN 1268, can be found at http://www.stsci.edu/~fruchter/GRB/011030 //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1272 SUBJECT: GRB011130 (XRF011130) Second Epoch Chandra Observations DATE: 02/03/15 03:33:31 GMT FROM: George Ricker at MIT GRB011130 (=XRF011130): Results of a Second Epoch Observation with the Chandra X-ray Observatory N. Butler, G. Monnelly, G. Ricker, J. Doty, P. Ford, R. Vanderspek, G. Crew, A. Dullighan (MIT); D. Lamb (U.Chicago); and P. Plucinsky (CFA) on behalf of the Chandra GRB ToO Team and the HETE Science Team write: On 20 February, from 10:02 UT - 14:30 UT, the Chandra Observatory targeted the field of the X-ray rich gamma-ray burst XRF011130, localized by the HETE satellite (Ricker et al., GCN1165) This was a 16 ksec observation with ACIS-I, following up the 30 ksec observation performed with ACIS-I on 10 December (Ricker et al., GCN 1185). Of the 20 brightest sources reported in GCN 1190 (Monnelly et al.), none were observed to fade in a manner that is consistent with the power-law behavior that is characteristic of gamma-ray burst afterglows. (A power law index of -1.3 implies a fade by a factor ~15, between our 1st and 2nd epoch observations.) Corrected for exposure, the largest fade for any of the sources in the list was by a factor of 3. We note that our brightest epoch 1 source (CXOU J030527.9+034657), which appears to be associated with a 20th magnitude galaxy (Mirabal & Halpern, GCN 1187), faded by a factor of approximately 2. Beyond the top 20 brightest, we note that our 24th and 27th brightest 1st epoch sources (see partial table below) faded to levels consistent with the background. We estimate a 50% probability for chance fading to the background in one or more of our 24 brightest sources; we estimate a 75% probability for chance fading to the background in one or more of our 27 brightest sources. Chandra Name RA DEC E1C E1B E2C E2B CXOU J030515.1+034457 3 5 15.12 3 44 57.02 8.1 2.9 4.0 -0.7 0.7 CXOU J030527.8+035548 3 5 27.81 3 55 48.09 13.8 4.2 6.5 -1.3 4.3 Here E1C denotes the epoch 1 net counts for the source, E1B the epoch 1 background counts estimate, the expected epoch 2 net number of counts based on epoch 1, E2C the observed net counts in epoch 2, and E2B the epoch 2 background counts estimate. A complete table in this form, containing all of our 1st epoch sources, can be found at: http://space.mit.edu/HETE/Bursts/GRB011130/epoch2_table.html This message may be cited.