//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 14828 SUBJECT: GRB 130609A: Swift detection of a burst DATE: 13/06/09 03:14:55 GMT FROM: David Palmer at LANL J. R. Cummings (NASA/UMBC), W. H. Baumgartner (GSFC/UMBC), N. Gehrels (NASA/GSFC), H. A. Krimm (CRESST/GSFC/USRA), D. Malesani (DARK/NBI), F. E. Marshall (NASA/GSFC), A. Maselli (INAF-IASFPA), D. M. Palmer (LANL), M. H. Siegel (PSU) and C. A. Swenson (PSU) report on behalf of the Swift Team: At 03:05:08 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 130609A (trigger=557782). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 152.676, +24.101 which is RA(J2000) = 10h 10m 42s Dec(J2000) = +24d 06' 05" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a single-peaked structure with a duration of about 10 sec. The peak count rate was ~2500 counts/sec (15-350 keV), at ~0 sec after the trigger. The XRT began observing the field at 03:06:15.4 UT, 66.8 seconds after the BAT trigger. Using promptly downlinked data we find an uncatalogued X-ray source located at RA, Dec 152.67159, 24.13359 which is equivalent to: RA(J2000) = 10h 10m 41.18s Dec(J2000) = +24d 08' 00.9" with an uncertainty of 3.9 arcseconds (radius, 90% containment). This location is 118 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. We cannot determine whether the source is fading at the present time. A power-law fit to a spectrum formed from promptly downlinked event data gives a column density in excess of the Galactic value (2.67 x 10^20 cm^-2, Kalberla et al. 2005), with an excess column of 2.4 (+2.79/-2.37) x 10^21 cm^-2 (90% confidence). UVOT took a finding chart exposure of 150 seconds with the White filter starting 70 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 none of the XRT error circle. 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 0.03. Burst Advocate for this burst is J. R. Cummings (jayc AT milkyway.gsfc.nasa.gov). 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: 14830 SUBJECT: GRB 130609A: P60 nondetection DATE: 13/06/09 05:28:54 GMT FROM: Daniel Perley at Caltech D. A. Perley (Caltech) and S. B. Cenko (GSFC) report: The Palomar 60-inch telescope automatically responded to GRB 130609A (Cummings et al., GCN 14828) and began taking observations at 04:03:23 UT (58.25 minutes after the BAT trigger) as soon as the sky became dark. A sequence of cycled 60-second r, i, and z images was acquired. We detect no source consistent with the XRT localization in either individual images or in combined stacks of the first 6 images in each filter. Approximate 5-sigma limiting magnitudes from the combined images at an approximate mean time of 4:20 UT (75 minutes after the GRB trigger) are: r > 22.5 i > 21.5 z > 20.9 These limits are suggestive of a dark GRB. Cummings et al. report a detection of significant excess absorption in the XRT spectrum, which may indicate a dust-extinguished (as opposed to high-redshift) event, although given the quoted errors there the excess may be only marginal. NIR follow-up is highly encouraged. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 14831 SUBJECT: GRB 130609A: RATIR Optical and NIR Observations DATE: 13/06/09 06:33:31 GMT FROM: Nat Butler at Az State U Nat Butler (ASU), Alan M. Watson (UNAM), Alexander Kutyrev (GSFC), William H. Lee (UNAM), Michael G. Richer (UNAM), Chris Klein (UCB), Ori Fox (UCB) J. Xavier Prochaska (UCSC), Josh Bloom (UCB), Antonino Cucchiara (UCSC), Eleonora Troja (GSFC), Owen Littlejohns (ASU), Enrico Ramirez-Ruiz (UCSC), José A. de Diego (UNAM), Leonid Georgiev (UNAM), Jesús González (UNAM), Carlos Román-Zúñiga (UNAM), Neil Gehrels (GSFC), and Harvey Moseley (GSFC) report: We observed the field of GRB 130609A (Cummings, et al., GCN 14828) with the Reionization and Transients Infrared Camera (RATIR; www.ratir.org) on the 1.5m Harold Johnson Telescope at the Observatorio Astronómico Nacional on Sierra San Pedro Mártir from 2013/06 9.15 to 2013/06 9.23 UTC (0.56 to 2.52 hours after the BAT trigger), obtaining a total of 1.24 hours exposure in the r' and i' bands and 0.60 hours exposure in the Z, Y, J, and H bands. For a source within the Swift-XRT error circle, in comparison with SDSS DR9 and 2MASS, we obtain the following upper limits (3-sigma): r' > 23.34 i' > 23.27 Z > 22.39 Y > 21.91 J > 21.72 H > 21.06 These magnitudes are in the AB system and not corrected for Galactic extinction in the direction of the GRB. We thank the staff of the Observatorio Astronómico Nacional in San Pedro Mártir. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 14834 SUBJECT: GRB 130609A, Swift-BAT refined analysis DATE: 13/06/09 13:43:19 GMT FROM: Jay R. Cummings at NASA/GSFC/Swift J. R. Cummings (GSFC/UMBC), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), A. Y. Lien (NASA/GSFC/ORAU), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU), G. Sato (ISAS), M. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (MSU) (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 130609A (trigger #557782) (Cummings, et al., GCN Circ. 14828). The BAT ground-calculated position is RA, Dec = 152.680, 24.124 deg which is RA(J2000) = 10h 10m 43.2s Dec(J2000) = +24d 07' 27.1" with an uncertainty of 1.2 arcmin, (radius, sys+stat, 90% containment). The partial coding was 87%. The mask-weighted light curve shows a single FRED peak. T90 (15-350 keV) is 7.0 +- 0.8 sec (estimated error including systematics). The time-averaged spectrum from T-1.19 to T+7.28 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.88 +- 0.11. The fluence in the 15-150 keV band is 5.7 +- 0.4 x 10^-07 erg/cm2. The 1-sec peak photon flux measured from T+0.52 sec in the 15-150 keV band is 1.8 +- 0.2 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/557782/BA/ //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 14835 SUBJECT: GRB 130609A: Enhanced Swift-XRT position DATE: 13/06/09 15:17:08 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 3372 s of XRT Photon Counting mode data and 4 UVOT images for GRB 130609A, 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 = 152.66941, +24.13195 which is equivalent to: RA (J2000): 10h 10m 40.66s Dec (J2000): +24d 07' 55.0" with an uncertainty of 2.3 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: 14837 SUBJECT: GRB 130609A: Swift-XRT refined Analysis DATE: 13/06/09 17:15:03 GMT FROM: Phil Evans at U of Leicester J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), C. Pagani (U. Leicester), A. Maselli (INAF-IASFPA), V. Mangano (INAF-IASFPA), A. Melandri (INAF-OAB), J.A. Kennea (PSU), M.C. Stroh (PSU), D.N. Burrows (PSU) and J.R. Cummings report on behalf of the Swift-XRT team: We have analysed 10 ks of XRT data for GRB 130609A (Cummings et al. GCN Circ. 14828), from 52 s to 23.5 ks after the BAT trigger. The data comprise 8 s in Windowed Timing (WT) mode (taken while Swift was slewing), with the remainder in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Evans et al. (GCN. Circ 14835). The light curve can be modelled with a power-law decay with a decay index of alpha=0.79 (+/-0.06). A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 2.6 (+0.4, -0.3). The best-fitting absorption column is 3.3 (+1.0, -0.9) x 10^21 cm^-2, in excess of the Galactic value of 2.7 x 10^20 cm^-2 (Kalberla et al. 2005). The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.2 x 10^-11 (7.9 x 10^-11) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Total column: 3.3 (+1.0, -0.9) x 10^21 cm^-2 Galactic foreground: 2.7 x 10^20 cm^-2 Excess significance: 5.4 sigma Photon index: 2.6 (+0.4, -0.3) If the light curve continues to decay with a power-law decay index of 0.79, the count rate at T+24 hours will be 3.5 x 10^-3 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.1 x 10^-13 (2.8 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/00557782. This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 14839 SUBJECT: GRB 130609A: Fermi GBM observation DATE: 13/06/09 20:20:46 GMT FROM: Gerard Fitzpatrick at UCD G. Fitzpatrick (UCD) and J. Michael Burgess (UAH) report on behalf of the Fermi GBM Team: At 03:05:10.69 UT on 09 June 2013, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 130609A (trigger 392439913 /130609129), which was also detected by the Swift/BAT (Cummings et al., GCN Circ. 14828). The GBM on-ground location is consistent with the Swift position. The GBM light curve consists of a single peak with a duration (T90) of about 5 s (50-300 keV). The time-averaged spectrum from T0-2.6 s to T0+2.8 s is adequately fit by a power law function with an exponential high-energy cutoff. The power law index is -1.2 +/- 0.2 and the cutoff energy, parameterized as Epeak, is 59.5 +/- 7.3 keV. The event fluence (10-1000 keV) in this time interval is (7.7 +/- 0.6)E-07 erg/cm^2. The 1-sec peak photon flux measured starting from T0-1.6 s in the 8-1000 keV band is 3.2 +/- 0.3 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 14863 SUBJECT: GRB 130609A: Radio Observations (5.8, 22 and 85 GHz) DATE: 13/06/10 23:18:16 GMT FROM: Ashley Zauderer at CfA B. A. Zauderer, W. Fong, E. Berger and T. Laskar (Harvard) report on behalf of the CARMA Key Project, "A Millimeter View of the Transient Universe" and a larger collaboration: "We observed the position of GRB 130609A (Cummings et al. GCN 14828; also detected by Fitzpatrick et al. GCN 14839) beginning 2013 Jun 9.88 UT (dt = 0.75 d) with the Very Large Array (VLA) and beginning 2013 Jun 10.05 UT (dt = 0.92 d) with the Combined Array for Research in Millimeter Astronomy (CARMA). For this dark burst with deep optical and NIR afterglow upper limits (e.g. Perley et al. GCN 14830 and Butler et al. GCN 14831), we find no significant radio emission at the enhanced Swift-XRT position (Evans et al.; GCN 14835) with the following three-sigma upper limits: 5.8 GHz <35 uJy (VLA) 21.8 GHz <60 uJy (VLA) 84.5 GHz <0.36 mJy (CARMA). We thank the VLA and CARMA staff and observers for their support of these observations." //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 14871 SUBJECT: GRB 130609A: Swift/UVOT Upper Limits DATE: 13/06/11 14:56:06 GMT FROM: Stephen Holland at STScI S. T. Holland (STScI) and J. R. Cummings (NASA/UMBC) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 130609A starting 70 s after the BAT trigger (Cummings et al. 2013, GCNC 14828). We do not detect any new source consistent with the UVOT-enhanced XRT position (Evans 2013, GCNC 14835) in any of the UVOT exposures. Preliminary 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the finding chart (FC) exposures and initial summed exposures are presented below. Filter TSTART TSTOP Exposure Mag ------------------------------------------------- white (FC) 70 220 147 >21.0 562 582 19 >19.8 u (FC) 282 532 246 >20.3 686 706 19 >18.6 ------------------------------------------------- v 612 6212 413 >19.9 b 537 18,175 1773 >21.7 u 5191 23,545 2254 >21.4 uvw1 4987 23,257 2164 >21.5 uvm2 4782 22,351 1279 >21.3 uvw2 4372 6007 393 >20.8 white 4166 12,406 1022 >22.0 ------------------------------------------------- The quoted upper limits have not been corrected for the expected extinction due to the Galactic reddening along the line of sight to this burst of E(B-V) = 0.03 mag (Schlafly et al. 2011, ApJS, 737, 103).