//////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3071 SUBJECT: GRB 050306: Swift-BAT detection of a long burst DATE: 05/03/06 04:48:27 GMT FROM: Craig Markwardt at NASA/GSFC/UMD C. Markwardt (GSFC/UMD), S. Barthelmy, L. Barbier, J. Cummings, (GSFC), E. Fenimore (LANL), N. Gehrels (GSFC), D. Hullinger (GSFC/UMD), H. Krimm (GSFC/USRA), F. Marshall (GSFC), P. Meszaros (PSU), D. Palmer (LANL), A. Parsons (GSFC), M. Perri (ASDC), T. Sakamoto (GSFC), G. Sato (ISAS), M. Suzuki (Saitama), T. Takahashi (ISAS), J. Tueller, N. White (GSFC) on behalf of the Swift-BAT team: At 03:33:12 UT, the Swift Burst Alert Telescope (BAT) triggered and located on-board GRB 050306. The burst location is 19 deg from the Moon, and because of the Moon constraint, the spacecraft did not slew to the burst location. Using the time interval of the burst, the ground-calculated location is RA,Dec 282.337,-9.162 (J2000) with an uncertainty of 3 arcmin (radius, including a systematic uncertainty, 90% containment). The burst was 51 degrees off the BAT boresight (19% encoding). The burst lightcurve has 2 main peaks. At this time we have access only to the TDRSS lightcuve which terminates at T+180 sec. The lightcurve starts to rise again at T+165 sec indicating a possible 3rd peak. The peak count rate is 2.4 counts/cm2/sec. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3072 SUBJECT: GRB 050306,optical observation DATE: 05/03/06 20:41:16 GMT FROM: Eri Sonoda at U of Miyazaki/Japan E.Sonoda,S.Maeno,Y.Matsuo,M.Yamauchi (University of Miyazaki) "We have observed the field covering the error box of GRB 050306 (GCN 3071 ; Swift-BAT Trigger time is 03:33:12 UT) with the unfiltered CCD camera on the 30-cm telescope at University of Miyazaki. The observation was started 18:13:46 UT on Mar.06. Observed field of view is 43 arcmin centerd on R.A=18h 49m 10s Dec=-09d 06m 54s After co-adding a set of 3 images of 30 sec exposures , we have compared with the USNO A2.0 and USNO B1.0 catalog. Preliminary analysis shows there is no new source brighter than 17.5 mag. " //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3073 SUBJECT: GRB 050306: TAROT optical observations DATE: 05/03/07 11:28:41 GMT FROM: Michel Boer at Obs Haute Prov. Klotz, A., Boer M. (OHP), Atteia, J.L., and G. Stratta (LATT) report: We imaged the entire field of GRB 050306 (cf. Markwardt et al. GCNC 3071) with the TAROT robotic telescope (D=25cm) located at the Calern observatory, France. Observations started 90 seconds after the begining of the burst. The source was at an elevation of 15 degrees above the horizon. The Moon did not rise during the observation, though the burst source location was 19 deg from it. Nevertheless, haze was present, resulting in a loss of sensitivity. No new source was detected after a comparison with the DSS2 R image. We summarize below the limiting magnitude obtained by TAROT : Beg. burst event 2005-03-06 03:33:12 UT (from GCNC 3071) End. burst event 2005-03-06 03:36:12 UT (from GCNC 3071) Date from to Rmag Remarks 2005-03-06 03:35:19 03:35:49 >11 during prompt emission 2005-03-06 03:36:42 03:40:32 >13 2005-03-06 03:41:37 03:43:31 >14.4 6 min after the end of prompt emission 2005-03-06 03:44:32 03:45:40 >13 This message is citable. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3075 SUBJECT: GRB 050306: Possible X-ray Afterglow Position from the Swift DATE: 05/03/07 23:08:47 GMT FROM: David Burrows at PSU/Swift M. Perri, P. Giommi, M. Capalbi, F. Tamburelli (ASDC), P. Romano, D. Malesani (INAF-OAB), V. Mangano, G. Cusumano, T. Mineo (INAF-IASF/Palermo), D. N. Burrows, D. C. Morris, J. Kennea, M. Chester (PSU), K. L. Page, P. T. O'Brien (U. Leicester), L. Angelini, N. Gehrels (GSFC), report on behalf of the Swift XRT team: GRB 050306 was within the Swift Moon avoidance angle until mid-day on 07 March 2005 (UT). Swift slewed to the BAT position (Markwardt et al. 2005, GCN 3071) at about 14:55 UT on 07 March 2005 as a Target of Opportunity and the XRT began observing it at 14:56:21 UT. Based on the first three orbits of data (4218 s of data in Photon-Counting mode), we find two point sources in our field of view, one of which is within the 3 arcminute radius BAT error circle. This X-ray source is not present in any X-ray catalog and its distance from the BAT position is ~105 arcsec. The coordinates of this source are: RA(J2000) = 18:49:14.0 Dec(J200) = -09:09:10.4 We estimate an uncertainty of about 6 arcseconds in this position. We have only detected 12 photons from this source at this time and cannot yet comment on whether it is fading. This source should be regarded as a possible X-ray afterglow candidate. Further observations are in progress, and these may allow us to make a more positive identification at a later date. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3076 SUBJECT: GRB 050306: REM optical-infrared observations DATE: 05/03/08 09:21:23 GMT FROM: Andrea Melandri at Rome Astro Obs A. Melandri, P. D'Avanzo, L. A. Antonelli, S. Covino, E. Palazzi, G. Tagliaferri, G. Chincarini, F. M. Zerbi, G. Tosti, A. Monfardini, N. Masetti, L. Nicastro, on behalf of the REM/ROSS team, report: "On Mar 07, 2005 the field of GRB050306 (Markwardt et al. GCN 3071) has been observed with the REM telescope located in La Silla (Chile). The field was imaged with both REM instruments (REM-IR and ROSS) in R, J, H and Ks filters starting at 8:28 UT (approximately 28.9 hours after the burst). Total integration time was of 32, 84, 84 and 94 seconds respectively. A faster observation could not be performed before due to the Moon proximity. In the position of the possible X-ray afterglow candidate (Perri et al. GCN 3075) no new source is clearly visible in our images. Comparison with USNO B1.0 and 2MASS catalogues did not reveal new sources down to a limiting magnitude of R > 17.0, J > 15.4, H > 15.2 and Ks > 15.0 (3-sigma upper limit). This message can be cited." ------------------------------------------------- This mail sent through IMP: http://horde.org/imp/ //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3077 SUBJECT: GRB 050306: No Swift UVOT Optical Counterpart Detected DATE: 05/03/08 12:41:47 GMT FROM: Pete Roming at PSU A. Blustin (MSSL), P. Brown (PSU), S. Rosen, K. McGowan, M. De Pasquale (MSSL), P. Boyd (GSFC/UMBC), S. T. Holland, M. Still (GSFC/USRA), W. Landsman (GSFC), S. Hunsberger (PSU), A. Breeveld (MSSL), P. Roming (PSU), K. Mason, P. Schady (MSSL), M. Ivanushkina (PSU), T. Poole (MSSL), C. Gronwall (PSU), B. Hancock (MSSL), S. Koch (PSU), M. Carter, H. Huckle (MSSL), P. Broos (PSU), T. Kennedy, P. Smith (MSSL), J. Nousek (PSU), N. Gehrels (GSFC), on behalf of the Swift UVOT team. The Swift Ultra-Violet/Optical Telescope (UVOT) began observations of GRB050128 (GCN 3071) on February 7, 2005 at 14:58:53 UT. Before this time GRB 050306 was within the Swift Moon avoidance angle. Over an 8,630s exposure combined from four snapshots between 35 and 41 hours after the trigger, we detect no new or variable source down to a V magnitude of 21.2 (5-sigma upper limit) in the BAT error circle. This includes the position of the X-ray candidate reported in GCN 3072. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3078 SUBJECT: GRB 050306: R-band observations DATE: 05/03/08 19:05:58 GMT FROM: Daniele Malesani at SISSA-ISAS,Trieste,Italy D. Fugazza, P. D'Avanzo, S. Covino (INAF-OABr), D. Malesani (SISSA), N. Masetti, E. Palazzi (IASF-CNR), L.A. Antonelli (INAF-OARm), and G. Andreuzzi (INAF-TNG), report on behalf of a larger Italian collaboration: We observed the field of GRB 050306 (Markwardt et al., GCN 3071) with the 3.6m TNG telescope, located in the Canary Islands. Observations were carried out in the R and I bands, under moderate observing conditions (high humidity, seeing ~1.5", airmass ~2). R-band observations started on 2004 Mar 8.22 UT (2.07 days after the burst), and yielded 20 minutes of net exposure. Inside the 6-arcsec error circle of the candidate X-ray afterglow (Perri et al., GCN 3075) we find several sources. Four of them are close to the center (to within ~3"), while the remaining ones are right on the border. All are fainter than the DSS limit. The large number of sources is consistent with the crowding of this field lying towards the Galactic plane. At this stage, we are not able to single out any candidate afterglow. Further observations are planned tonight in order to seek for variable objects. This message can be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3079 SUBJECT: GRB 050306: CORRECTION to date of observation DATE: 05/03/08 20:00:52 GMT FROM: Patricia Schady at MSSL/Swift A. Blustin (MSSL), P. Brown (PSU), S. Rosen, K. McGowan, M. De Pasquale (MSSL), P. Boyd (GSFC/UMBC), S. T. Holland, M. Still (GSFC/USRA), W. Landsman (GSFC), S. Hunsberger (PSU), A. Breeveld (MSSL), P. Roming (PSU), K. Mason, P. Schady (MSSL), M. Ivanushkina (PSU), T. Poole (MSSL), C. Gronwall (PSU), B. Hancock (MSSL), S. Koch (PSU), M. Carter, H. Huckle (MSSL), P. Broos (PSU), T. Kennedy, P. Smith (MSSL), J. Nousek (PSU), N. Gehrels (GSFC), on behalf of the Swift UVOT team. The Swift Ultra-Violet/Optical Telescope (UVOT) began observations of GRB050306 (GCN 3071) on March 7th, 2005 at 14:58:53 UT. Before this time GRB 050306 was within the Swift Moon avoidance angle. Over an 8,630s exposure combined from four snapshots between 35 and 41 hours after the trigger, we detect no new or variable source down to a V magnitude of 21.2 (5-sigma upper limit) in the BAT error circle. This includes the position of the X-ray candidate reported in GCN 3072. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3084 SUBJECT: GRB 050306: further TAROT optical data DATE: 05/03/10 17:46:14 GMT FROM: Michel Boer at Obs Haute Prov. Klotz, A., Boer M. (OHP), Atteia, J.L., and G. Stratta (LATT) report: We analyzed images taken 1 hour after GRB 050306 (cf. Markwardt et al. GCNC 3071) with the TAROT robotic telescope (D=25cm) located at the Calern observatory, France. The source was at an elevation of 22 to 26 degrees above the horizon but images are of good quality. We coadded 29 images of 30s with no filter. No new source was detected at the limiting magnitude R~17.5 after a comparison with the DSS2 R and 2MASS images and the USNO-B1 catalogue. We summarize below the limiting magnitude obtained by TAROT: Date from to Rmag Remarks 2005-03-06 04:18:54 04:53:02 >17.5 45 to 80 min after GRB We also revised the limiting magnitude of the following measurement 14.0 6 min after the end of prompt emission We analyzed the 2MASS catalogue to extract the galactic extinction through the line of sight of GRB050306. We used the method described in Klotz et al. (A&A 2004, 425, p427). From Earth to a distance modulus of about 9.5-10.5, the visual extinction is Av=2 +/-1. The 2MASS data don't allow probing farer distances. TAROT data for this GRB is summarized at the following URL: http://www.cesr.fr/~klotz/grb050306/ This message is citable. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3086 SUBJECT: GRB 050306: Confirmation of X-ray afterglow DATE: 05/03/11 17:51:30 GMT FROM: David Burrows at PSU/Swift V. Mangano, G. Cusumano, T. Mineo (INAF-IASF/Palermo), M. Perri, P. Giommi, M. Capalbi, F. Tamburelli (ASDC), D. N. Burrows, D. C. Morris, J. Hill, M. Chester (PSU), A. Moretti, D. Malesani (INAF-OAB), O. Godet, P. T. O'Brien (U. Leicester), L. Cominsky (Sonoma State U.), J. Greiner (MPE), D. Hinshaw, and N. Gehrels (GSFC), report on behalf of the Swift XRT team: The Swift X-Ray Telescope (XRT) observed the field of GRB 050306 (GCN 3071, Markwardt et al.) for a second time on 2005-03-10 from 01:08:09 UT until 15:46:39 UT. We confirm that the source identified by Perri et al. (GCN 3075) has faded from view and is therefore the likely X-ray afterglow of this burst. Only the Photon Counting mode, which provides the best XRT sensitivity, was used for this observation. The total exposure time was 10205 s. No X-ray emission was found from the XRT candidate afterglow detected on March 7 during the first XRT follow-up observation of the field (GCN 3075, Perri et al.). We place a three sigma upper limit on the 0.5-10 keV count rate of 1.4e-3 cts/s which is significantly lower than the count rate observed on March 7 (3.3e-3 cts/s), implying that the source has faded. We conclude that the candidate reported in GCN 3075 is the X-ray afterglow of GRB 050306. The updated position for this source is: RA(J2000) = 18 49 14.1 Dec(J2000) = -09 09 11.2 This position is based on 12322s of data from March 7, 2005 (about 3 times the amount used in our preliminary report in GCN 3075). The position uncertainty is estimated to be about 6 arcseconds. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3089 SUBJECT: GRB 050306: optical afterglow DATE: 05/03/12 18:46:02 GMT FROM: Daniele Malesani at SISSA-ISAS,Trieste,Italy P. D'Avanzo, D. Fugazza, S. Covino (INAF-OABr), D. Malesani (SISSA), N. Masetti, E. Palazzi (IASF-CNR), L.A. Antonelli, G.L. Israel (INAF-OARm), and G. Andreuzzi (INAF-TNG), report on behalf of a larger Italian collaboration: We imaged again (Fugazza et al., GCN 3078) the field of GRB 050306 (Markwardt et al., GCN 3071) with the Italian TNG telescope. Observations were carried out under a clear sky and with a seeing of about 1.6", starting on 2005 Mar 9.247 UT. Seven R-band exposures were acquired, with an overall exposure time of 21 minutes (mean UT Mar 9.260, i.e. 3.11 days after the burst). Inside the revised error circle of the XRT afterglow (Perri et al., GCN 3075; Mangano et al., GCN 3086), we detect several sources. After performing PSF photometry with DAOPhot, we find that the object at coordinates: alpha(J2000) = 18:49:13.95 delta(J2000) = -09:09:08.6 (that is, 3.5" off the XRT centroid position) has faded by 0.54+-0.10 mag since our previous observation, carried out ~2.1 days after the GRB (Fugazza et al., GCN 3078). Assuming a powerlaw decay (F(t) = K*t^-delta), this corresponds to delta = 1.28+-0.24, a value typical among GRB afterglows at comparable epochs. We thus propose that this object is the optical afterglow of GRB050603. Based on calibration upon USNO stars, the object has R ~ 23 at the time of our first observation, Mar 8.25 UT. A finding chart of the field is posted at the following URL: http://www.sissa.it/~malesani/GRB/050306 Further observations are planned at the TNG in the following nights, but no spectroscopy will be possible. We warmly acknowledge the TNG staff for carefully performing the observations. This message can be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3091 SUBJECT: GRB050306: 250 GHz upper limit with MAMBO at the IRAM 30m DATE: 05/03/12 23:05:51 GMT FROM: Frank Bertoldi at MPIFR/Bonn F. Bertoldi (RAIUB Bonn), D.A. Frail (NRAO), A. Weiss (IRAM), K.M. Menten (MPIfR Bonn), S. Kulkarni (Caltech), A. Soderberg (Caltech) report: We observed the position initially reported for the GRB 050306 X-ray afterglow by Perri et al. (GCN 3075), RA 18:49:14.0, Dec -09:09:10.4 (J2000), with the Max-Planck-Millimeter Bolometer (MAMBO-2) array at the IRAM 30-m telescope on 8 March 2005, between UT 8 and 9 h, and obtained a non-detection of S_nu(250 GHz,1.20mm) = 0.26 +/- 0.55 mJy (1 sigma error). The MAMBO-2 bolometer detectors cover 210-290 GHz (half power). The likely optical afterglow reported by D'Avanzo et al. (GCN 3089) is 1.9 arcsec from our pointing position, and well within our 10.7 arcsec FWHM beam. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3092 SUBJECT: GRB 050306: Radio Observations DATE: 05/03/14 21:16:03 GMT FROM: Alicia Soderberg at Caltech A. M. Soderberg (Caltech) and D. A. Frail (NRAO) report: "Using the Very Large Array, we observed the field of GRB 050306 (GCN 3071) at 8.5 GHz on Mar 14.42 UT. We detect no source above our detection limit of 56 uJy (2-sigma) within the XRT position (GCN 3086) which includes the location of the optical afterglow candidate (GCN 3089)." //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3107 SUBJECT: GRB 050306: ROTSE-III early limits DATE: 05/03/16 23:13:55 GMT FROM: Robert Quimby at U of Texas/ROTSE R. M. Quimby, E. S. Rykoff, B. E. Schaefer, D. A. Smith and S. A. Yost report on behalf of the ROTSE collaboration: ROTSE-IIIc, located at the H.E.S.S. site at Mt. Gamsberg, Namibia, responded automatically to Swift GRB 050306 (Markwardt et al., GCN 3071) with the first 5-second exposure beginning Mar 6, 03:34:16.7 UT, 64.8 seconds after the burst. Comparison to the DSS (second epoch) reveals no new sources, but we are limited by crowding in this low galactic latitude field. Using software provided by the Supernova Cosmology Project, we have subtracted ROTSE-IIIc data obtained on Mar. 8 from our first Mar 6 image. No sources are detected on the subtracted frame within the Swift XRT error circle (Perri et al., GCN 3075). In particular, we set a 3-sigma upper limit on the magnitude of 15.8 (unfiltered, relative to USNO A2.0) at the location of the TNG source (D'Avanzo et al., GCN 3089). An extrapolation of a simple power-law with an index of 1.28 from the TNG detection back to the epoch of our first image would predict a ~12 mag source. However, our non-detection is consistent with other optical light curves that are underluminous at early times such as GRBs 030418 and 030723 (Rykoff et al., 2004 ApJ 601,1013) //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3482 SUBJECT: GRB050306: optical afterglow not confirmed DATE: 05/05/25 20:44:35 GMT FROM: Paolo D'Avanzo at INAF-OAB P. D'Avanzo, D. Fugazza, S. Covino (INAF-OABr), D. Malesani (SISSA), N. Masetti, E. Palazzi (IASF-CNR), L.A. Antonelli, G.L. Israel (INAF- OARm), report on behalf of a larger Italian collaboration: A detailed reanalysis of our images (Fugazza et al., GCN 3078; D'Avanzo et al., GCN 3089) of the field of the Swift GRB 050306 (Markwardt et al., GCN 3071; Perri et al., GCN 3075) does not allow to confirm the variability of the candidate afterglow proposed in GCN 3089. At this stage, no afterglow detection for this burst can be claimed from our observations. This message may be cited.