//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11296 SUBJECT: GRB 100925A: Swift detection of a burst DATE: 10/09/25 08:45:18 GMT FROM: Vanessa Mangano at INAF-IASFPA V. Mangano (INAF-IASFPA), E. A. Hoversten (PSU), C. B. Markwardt (NASA/GSFC), B. Sbarufatti (INAF-OAB/IASFPA), R. L. C. Starling (U Leicester) and T. N. Ukwatta (GSFC/GWU) report on behalf of the Swift Team: At 08:05:05 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 100925A (trigger=434928). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 254.736, -15.236 which is RA(J2000) = 16h 58m 57s Dec(J2000) = -15d 14' 07" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). This is an image trigger with on-board significance of 8.1 sigma. As is typical for image triggers, there is no obvious structure in the raw light curve. The XRT began observing the field at 08:36:18.0 UT, 1872.2 seconds after the BAT trigger. XRT found a bright, uncatalogued X-ray source located at RA, Dec 254.7603, -15.2576 which is equivalent to: RA(J2000) = 16h 59m 02.47s Dec(J2000) = -15d 15' 27.3" with an uncertainty of 5.3 arcseconds (radius, 90% containment). This location is 115 arcseconds from the BAT onboard position, within the BAT error circle. No event data are yet available to determine the column density using X-ray spectroscopy. UVOT took a finding chart exposure of 150 seconds with the White filter starting 1882 seconds after the BAT trigger. No credible afterglow candidate has been found in the initial data products. Data from the 2.7'x2.7' sub-image are not available at this time. 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 0.61. Burst Advocate for this burst is V. Mangano (vanessa AT ifc.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: 11298 SUBJECT: GRB100925A UVOT afterglow DATE: 10/09/25 12:23:06 GMT FROM: Phil Evans at U of Leicester F. E. Marshall (NASA/GSFC) reports on behalf of the Swift team: In response to GRB100925 (Swift/BAT trigger 434928), UVOT took a finding chart exposure of 150 seconds with the White filter starting 1882 seconds after the BAT trigger. There is a candidate afterglow in the rapidly available 2.7'x2.7' sub-image at RA(J2000) = 16:59:01.68 = 254.75702 DEC(J2000) = -15:15:28.4 = -15.25789 with a 90%-confidence error radius of about 0.61 arc sec. This position is 11" from the center of the XRT error circle (Mangano et al. GCN Circ. 11296). The estimated magnitude is 16.83 with a 1-sigma error of about 0.14. No correction has been made for the expected extinction corresponding to E(B-V) of 0.61. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11299 SUBJECT: GRB 100925A: Nearby DSS Source - SN-GRB or new Galactic transient? DATE: 10/09/25 13:55:24 GMT FROM: Alexander Kann at TLS Tautenburg D. A. Kann (TLS Tautenburg) speculates: GRB 100925A (Mangano et al., GCN 11296) is a very peculiar event. It was an extremely long image trigger (1592 seconds), yet, after slewing to it, Swift discovered that the X-ray afterglow is still bright. Furthermore, looking at the Swift XRT repository page (Evans et al. 2007, 2009) (http://www.swift.ac.uk/xrt_curves/00434928/) the source remains constantly bright over almost 9000 seconds (two orbits). Inspection of the DSS images of this field, using the position of the bright UVOT transient (Marshall, GCN 11298), shows that there is what seems to be an extended source a few arcseconds to the west (R.A.: 16:59:01.501; Dec.: -15:15:28.76 according to the native DSS WCS system). It is clearly detected in the red frame, and more marginally in the IR frame (DSS blue or SDSS are not available for this field). There are also some stars nearby, but at much larger separation (> 10 arcsec). There is no source directly beneath the UVOT position. While the initial properties are reminiscent of two local XRFs associated with broadlined Type Ic SNe, namely XRF 060218 (Campana et al. 2006) and XRF 100316D (Starling et al. 2010) (the nearby DSS source being the host galaxy), the continuing strong X-ray emission as well as the position near the Galactic bulge (Galactic longitude 5.52, Galactic latitude 16.56) may also point to a new Galactic source. Spectroscopic follow-up is encouraged. This message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11300 SUBJECT: MAXI J1659-152: Swift-BAT refined analysis (triggers 434928 and 434931) DATE: 10/09/25 18:55:41 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), V. Mangano (INAF-IASFPA), C. B. Markwardt (GSFC), 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 only a partial data set from T+247 to T+303, T+706 to T+723 and T+728 to T+963 sec (T=08:05:06 UT) from recent downlinks, we report further analysis of MAXI J1659-152 (Swift-BAT trigger #434928) (Negoro, ATEL 2873 and initially reported as GRB 100925A in Mangano, et al., GCN Circ. 11296). The BAT ground-calculated position is RA, Dec = 254.750, -15.206 deg, which is RA(J2000) = 16h 59m 00.0s Dec(J2000) = -15d 12' 20.1" with an uncertainty of 2.9 arcmin, (radius, sys+stat, 90% containment). The partial coding was 38%. No statement can be given about the BAT lightcurve because of the fragmented coverage of the transient. This fragmentation is caused by (a) a second Swift-BAT trigger on the same source (a 64-sec image trigger, #434931, at 09:47:13 UT) and (b) the very long integration time of the first trigger (26.5 min). The normal set of event-by-event data used to do this "refined" analysis is not fully available (the on-board event ring buffer has been nearly completely wrapped). The time-averaged spectrum in the 3 time intervals listed above is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.79 +- 0.43. We caution even this limited analysis because of the partial coverage of the time interval of the event. Further, the time-averaged spectrum from T+0.0 to T+64.0 sec (T=09:47:13 UT, the second trigger) is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 2.36 +- 0.61. All the quoted errors are at the 90% confidence level. The GCN Notices for the first trigger were distributed with a GRB label, because the location did not match any known source in the on-board and ground catalogs. However, the GCN Notices for the second trigger were labeled as a transient because the location matched the location of the first trigger (AT trigger locations are maintained in the on-board catalog up to the 4th trigger in a 3-deep ring buffer). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11301 SUBJECT: GRB 100925A / MAXI J1659-152: BOOTES-2/TELMA and IAC80 optical observations DATE: 10/09/25 22:09:39 GMT FROM: Alberto Castro-Tirado at Inst.de Astro. de Andalucia M. Jelínek (IAA-CSIC Granada), C. Zurita, M. Visús (IAC Tenerife), P. Papics (Katholieke Universiteit Leuven), P. Kubánek (IPL, Univ. de Valencia), L. Sabau-Graziati (INTA), A, de Ugarte Postigo (DARK/NBI), R. Cunniffe, J. Gorosabel and A. J. Castro-Tirado (IAA-CSIC), report on behalf of a larger collaboration: "Following the detection of MAXI J1659-152 (Negoro et al. ATEL 2873) by Swift (GRB 100925A, Magano et al. GCNC 11296), we have obtained further observations at the position of the optical counterpart reported by Marshall et al. (GCNC 11298) with the 0.6m TELMA robotic telescope at the BOOTES-2 station in Málaga and the 0.8m IAC telescope at Observatorio del Teide in Tenerife (Spain). TELMA observations started on 25 Sep 20.1 UT in the R-band filter. IAC80 observations were carried out in BVRI with dense monitoring in the R-band. For a combined image (120 x 20s) Preliminary analysis yields R = 16.6 +/- 0.1 (based on USNO B-1.0 magnitude for a 15.5 star 1 arcmin north of the target), thus supporting a Galactic transient (Kann, GCNC 11299), either a hard outburst of a new compact binary, or a magnetar candidate similarly to GRB 070610/SWIFT J195509+261406 (Castro-Tirado et al. 2008, Nat 405, 556; Stefanescu et al. 2008, Nat 405, 503). Spectroscopic observations are most essential to discern its nature." This message can be quoted. [GCN OPS NOTE(26sep10): Per author's request, the Kann citation was added and 071006 was changed to 070610.] //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11302 SUBJECT: GRB 100925A/MAXI J1659-152 - NOT optical observations DATE: 10/09/26 00:08:46 GMT FROM: Annalisa De Cia at U of Reykjavik,Science Inst. A. De Cia (U. of Iceland), D. Malesani (DARK/NBI), Remy Avila (UNAM), Graham Cox (NOT), Vik Dhillon (U. of Sheffield), James Osborn, Richard Wilson (U. of Durham), P.M. Vreeswijk and P. Jakobsson (U. of Iceland) report on behalf of a larger collaboration: We observed the field of GRB 100925A/MAXI J1659-152 (Marshall et al., GCN 11298, Negoro et al., ATEL 2873) with the Nordic Optical Telescope (NOT) on La Palma, equipped with StanCam, in poor weather conditions. We detect the source reported by Marshall et al., estimating a magnitude R = 16.4 +/- 0.3 at 21:28 UT (13.4 hours after the BAT trigger), calibrated against USNO B1 stars. We thank the Nordic Optical Telescope Scientific Association for the use of NOT facilities. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11304 SUBJECT: GRB 100925A/MAXI J1659-152: Submm observations from APEX DATE: 10/09/26 01:51:55 GMT FROM: Antonio Deugarte at IAA-CSIC A. de Ugarte Postigo (Dark/NBI), A. Lundrgren (ESO), F. Wyrowski (MPIfR), C.C. Thoene (NBIA), A. J. Castro-Tirado, J. Gorosabel, M. Jelinek (IAA-CSIC) report on behalf of a larger collaboration: "We observed the field of GRB 100925A/MAXI J1659-152 (Mangano et al. GCNC 11296, Negoro et al. ATel 2873, Barthelmy et al. GCNC 11300), a burst with possible Galactic origin (Kann GCNC 11299, Xu GCNC 11303), using LABOCA/APEX at Chajnantor (Chile) in the 870 micrometer band. Observations began on September 25th at 23:30 UT (15.5 hours after the burst onset). In a preliminary analysis we detect emission at the position of the optical afterglow (Marshall et al., GCNC 11298, Jelinek et al., GCNC 11301, De Cia et al. GCNC 11302) at a flux of 12.6+/-2.4 mJy." //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11305 SUBJECT: GRB 100925A / MAXI J1659-152: SARA-S Observations DATE: 10/09/26 04:03:03 GMT FROM: Adria C. Updike at Clemson U Adria C. Updike and Dieter H. Hartmann (Clemson University) report: We observed the field of GRB 100925A / MAXI J1659-152 (Mangano et al., GCN 11296) using the SARA-South 0.6m telescope located at CTIO beginning 15 hours after the trigger and continuing for 3 hours in the BVRI Bessel filters under good conditions. We clearly detect the source (Marshall, GCN 11298) in each image. Filter Exp Time Magnitude --------------------------------- B 120s 16.8 +/- 0.1 V 120s 16.3 +/- 0.1 R 120s 16.3 +/- 0.1 I 120s 16.1 +/- 0.1 Magnitudes are given relative to field stars in the USNO B1.0 and NOMAD catalogs. This message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11306 SUBJECT: GRB100925A/MAXI J1659-152 MITSuME Ishigakijima and Okayama Optical Observation DATE: 10/09/26 08:20:38 GMT FROM: Daisuke Kuroda at OAO/NAOJ D. Kuroda (OAO, NAOJ), H. Hanayama (IAO, NAOJ), K. Yanagisawa, Y. Shimizu, H. Toda (OAO, NAOJ), S. Nagayama, T. Miyaji, J. Watanabe (NAOJ), M. Yoshida (Hiroshima), K. Ohta (Kyoto) and N. Kawai(Tokyo Tech) report on behalf of the MITSuME collaboration: We observed the field of GRB 100925A / MAXI J1659-152 (Mangano et al., GCN 11296; Barthelmy et al., GCN 11300) with the optical three color (g', Rc and Ic) CCD camera attached to the MITSuME 50cm telescope of Okayama Astrophysical Observatory and the Murikabushi 1m telescope of Ishigakijima Astronomical Observatory. We detected the previously reported source at the UVOT position (Marshall, GCN 11298) in all the three bands. Photometric results of the OT are listed below. We used GSC2.3 catalog for flux calibration. Okayama Astrophysical Observatory: The observation started on 2010-09-25 09:58:43 UT (~ 1.9 h after the trigger). #T0+[day] MID-UT T-EXP[sec] g' g'_err Rc Rc_err Ic Ic_err ---------------------------------------------------------------------- 0.08949 10:13:57 1560.0 17.13 0.06 16.46 0.03 16.45 0.16 0.11081 10:44:39 1500.0 17.08 0.08 16.61 0.04 16.32 0.19 0.13201 11:15:11 1560.0 17.15 0.09 16.46 0.05 15.98 0.15 Ishigakijima Astronomical Observatory: The observation started on 2010-09-25 10:53:50 UT (~ 2.8 h after the trigger). #T0+[day] MID-UT T-EXP[sec] g' g'_err Rc Rc_err Ic Ic_err ---------------------------------------------------------------------- 0.12082 10:59:03 480.0 16.97 0.04 16.48 0.02 16.24 0.03 0.12818 11:09:40 540.0 17.05 0.03 16.52 0.02 16.32 0.03 0.13556 11:20:17 540.0 17.02 0.04 16.52 0.02 16.30 0.02 T0+ : Elapsed time after the burst [day] T-EXP: Total Exposure time [sec] //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11307 SUBJECT: GRB100925A/MAXI J1659-152: X-shooter identification as an X-ray binary DATE: 10/09/26 09:25:09 GMT FROM: Antonio Deugarte at IAA-CSIC A. de Ugarte Postigo (DARK/NBI), H. Flores (Paris Obs.), K. Wiersema (U. Leicester), C.C. Thoene (NBIA), J.P.U. Fynbo (DARK/NBI), P. Goldoni (APC/Univ. Paris 7 and SAp/CEA) report on behalf of the X-shooter GRB collaboration: We have observed the optical source related to GRB 100925A/MAXI J1659-152 (Mangano et al. GCN Circ. 11296, Marshall et al. GCN Circ. 11298) using the X-shooter spectrograph mounted at the Kueyen telescope of ESO's VLT (Paranal Observatory, Chile). The spectrum consists of a combined exposure of 2x600s and was started at 23:40 UT on September 25. The spectrum covers the complete range from 3000 to 24800 angstroms. In a preliminary analysis we identify broad emission lines from the Balmer series of hydrogen and HeII as well as CaII and Na I absorption from the ISM of the MW, all at redshift zero. The emission lines have a width of about 2000 km/s showing a double peak profile. The spectrum is consistent with that of an X-ray binary and we hence confirm that GRB 100925A/MAXI J1659-152 is a Galactic source (Kann GCN Circ. 11299, Negoro et al. ATEL 2873). We thank the Paranal staff for excellent support, in particular Claudio Melo. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11308 SUBJECT: GRB 100925A / MAXI J1659-152: Optical observation with the Kottamia 188cm telescope DATE: 10/09/26 19:37:50 GMT FROM: Michitoshi Yoshida at HASC,Hiroshima U M. Yoshida, K. S. Kawabata (HASC, Hiroshima U.), Gamal B. Ali, A. Haroon, A. Essam, I. Zead, A. Nakhlawy, and M. Ismail (NRIAG, Egypt) report: We observed GRB 100925A / MAXI J1659-152 (Mangano et al., GCN 11296;Barthelmy et al., GCN 11300; Marshall et al. GCN 11298; Negoro et al.ATEL 2873) with the Newtonian CCD camera attached to the 188 cm telescope of Kottamia Astronomical Observatory in Egypt on September 26 2010. We measured the brightness of this possible X-ray binary (Ugarte Postigo et al. GCN 11307) in B, V, R and I bands. Results of the photometry are listed below. We used a nearby USNO B1.0 star (USNO 0747-0361593) for photometric calibration. band START-UT T-EXP[sec] mag.(Vega) error(*) ------------------------------------------------------------- B 2010-09-26 18:11:24 300.0 16.64 0.08 V($) 2010-09-26 18:17:05 180.0 16.33 0.06 R 2010-09-26 17:59:24 120.0 16.11 0.05 I 2010-09-26 18:01:59 120.0 15.87 0.04 ------------------------------------------------------------- (*) Poisson noise error only. ($) We interpolated the B2 and the R2 magnitudes of the comparison star to estimate the V band magnitude of the star. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11309 SUBJECT: GRB 100925A / MAXI J1659-152: WSRT Radio and Polarization Detection DATE: 10/09/27 01:15:56 GMT FROM: Alexander van der Horst at NASA/MSFC A.J. van der Horst (NASA/MSFC/ORAU), J. Granot (U of Hertfordshire), Z. Paragi (JIVE), C. Kouveliotou (NASA/MSFC), R.A.M.J. Wijers (U of Amsterdam) and E. Ramirez-Ruiz (UC Santa Cruz) report: "We observed the position of the hard X-ray transient GRB 100925A / MAXI J1659-152 (GCN 11296, ATel #2873, GCN 11307) with the Westerbork Synthesis Radio Telescope at 4.8 GHz, at September 26 14.27 to 19.75 UT, i.e. 1.37 days after the Swift/BAT trigger (GCN 11296) and 1.60 days after the start of the source brightening in MAXI/GSC (ATel #2873). We detect a radio source at the Swift/UVOT position of the transient (GCN 11298), with a flux density of 4.92 +/- 0.04 mJy. The source is linearly polarized at a level of 23 +/- 2 %, but there is no circular polarization detected, with a 3-sigma upper limit of 2 %. We would like to thank the WSRT staff for rapidly scheduling and obtaining these observations." //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11314 SUBJECT: GRB 100925A / MAXI J1659-152: MASTER optical observations DATE: 10/09/29 16:00:26 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs E. Gorbovskoy, V.Kornilov, V. Lipunov, A.Belinski, N.Shatskiy, N.Tyurina, P.Balanutsa, V.V.Chazov, D.Kuvshinov, , A.Kuznetsov, D.Zimnukhov, M. Kornilov, A.Sankovich Sternberg Astronomical Institute, Moscow State University K.Ivanov, O.Chuvalaev, V.Poleschuk, E.Konstantinov, V.Lenok, O.Gres, S.Yazev, N.M.Budnev, Irkutsk State University A. Tlatov, A.V. Parhomenko, D. Dormidontov, V.Sennik Kislovodsk Solar Station of the Pulkovo Observatory V.Yurkov, Yu.Sergienko, D.Varda, I.Kudelina Blagoveschensk Educational State University, Blagoveschensk V.Krushinski, I.Zalozhnich, T.Kopytova, A. Popov Ural State University, Kourovka We observed GRB 100925A / MAXI J1659-152 (Mangano et al., GCN 11296; Barthelmy et al., GCN 11300; Marshall et al. GCN 11298; Negoro et al.ATEL 2873) in automatic regime after sunset at Tunka and Kislovodsk (MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, pp. 1-7). The elevation of the source was about 15 degrees at Tunka and about 22 degrees at Kislovodsk. The results of the R photometry are: Date JD T-T_trigger [day] R[mag] [+-] Site 2010-09-25 12:09:27 2455465.00657 0.098 16.08 0.25 Tunka 2010-09-26 02:54:12 2455465.62098 0.274 16.14 0.20 Tunka 2010-09-26 16:25:36 2455466.18445 1.276 16.20 0.10 Kislo This photometry calibrated by USNOB1 stars. The message may be cited. mailto: lipunov@sai.msu.ru