//////////////////////////////////////////////////////////////////////// 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: 14841 SUBJECT: GRB 130609B: Swift detection of a burst with an optical counterpart DATE: 13/06/09 21:46:41 GMT FROM: Scott Barthelmy at NASA/GSFC H. A. Krimm (CRESST/GSFC/USRA), S. D. Barthelmy (GSFC), D. N. Burrows (PSU), J. A. Kennea (PSU), D. Malesani (DARK/NBI), C. B. Markwardt (NASA/GSFC), F. E. Marshall (NASA/GSFC) and A. Maselli (INAF-IASFPA) report on behalf of the Swift Team: At 21:38:40 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 130609B (trigger=557828). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 53.754, -40.153 which is RA(J2000) = 03h 35m 01s Dec(J2000) = -40d 09' 11" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve shows multiple peaks with a total duration of at least 200 sec. The peak count rate was ~8500 counts/sec (15-350 keV), at ~2 sec after the trigger. The XRT began observing the field at 21:39:56.4 UT, 76.0 seconds after the BAT trigger. XRT found a bright, uncatalogued X-ray source located at RA, Dec 53.7695, -40.1747 which is equivalent to: RA(J2000) = +03h 35m 4.68s Dec(J2000) = -40d 10' 28.9" with an uncertainty of 4.9 arcseconds (radius, 90% containment). This location is 89 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 nominal 150.000 seconds with the White filter starting 84 seconds after the BAT trigger. There is a candidate afterglow in the list of sources generated on-board at RA(J2000) = 03:35:05.11 = 53.77128 DEC(J2000) = -40:10:26.6 = -40.17406 with a 90%-confidence error radius of about 1.10 arc sec. This position is 5.4 arc sec. from the center of the XRT error circle. The estimated magnitude is 15.71. No correction has been made for the expected extinction corresponding to E(B-V) of 0.01. Burst Advocate for this burst is H. A. Krimm (krimm 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: 14847 SUBJECT: GRB 130609B: Enhanced Swift-XRT position DATE: 13/06/10 06:30:59 GMT FROM: Phil Evans at U of Leicester M.R. Goad, J.P. Osborne, A.P. Beardmore and P.A. Evans (U. Leicester) report on behalf of the Swift-XRT team. Using 2407 s of XRT Photon Counting mode data and 5 UVOT images for GRB 130609B, 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 = 53.77097, -40.17407 which is equivalent to: RA (J2000): 03h 35m 5.03s Dec (J2000): -40d 10' 26.7" with an uncertainty of 1.7 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: 14852 SUBJECT: GRB 130609B: Swift-XRT refined Analysis DATE: 13/06/10 14:46:03 GMT FROM: Phil Evans at U of Leicester C. Pagani (U. Leicester), A. Melandri (INAF-OAB), B. Sbarufatti (INAF-OAB/PSU), G. Stratta (ASDC), D.N. Burrows (PSU), J.A. Kennea (PSU), M.C. Stroh (PSU), A.P. Beardmore (U. Leicester), P.A. Evans (U. Leicester) and H.A. Krimm report on behalf of the Swift-XRT team: We have analysed 7.0 ks of XRT data for GRB 130609B (Krimm et al. GCN Circ. 14841), from 66 s to 46.7 ks after the BAT trigger. The data comprise 1.4 ks in Windowed Timing (WT) mode (the first 9 s were taken while Swift was slewing) with the remainder in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Goad et al. (GCN. Circ 14847). The late-time light curve (from T0+5.4 ks) can be modelled with an initial power-law decay with an index of alpha=1.42 (+0.14, -0.56), followed by a break at T+13.6 ks to an alpha of 2.36 (+0.38, -0.22). A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 1.840 (+/-0.029). The best-fitting absorption column is 1.40 (+0.08, -0.07) x 10^21 cm^-2, in excess of the Galactic value of 1.4 x 10^20 cm^-2 (Kalberla et al. 2005). The PC mode spectrum has a photon index of 2.01 (+/-0.10) and a best-fitting absorption column of 1.28 (+0.26, -0.24) x 10^21 cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.7 x 10^-11 (5.0 x 10^-11) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Total column: 1.28 (+0.26, -0.24) x 10^21 cm^-2 Galactic foreground: 1.4 x 10^20 cm^-2 Excess significance: 7.6 sigma Photon index: 2.01 (+/-0.10) If the light curve continues to decay with a power-law decay index of 2.36, the count rate at T+24 hours will be 8.4 x 10^-3 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 3.1 x 10^-13 (4.1 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/00557828. This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 14856 SUBJECT: Konus-Wind observation of GRB 130609B DATE: 13/06/10 16:22:33 GMT FROM: Dmitry Frederiks at Ioffe Institute S. Golenetskii, R.Aptekar, D. Frederiks, V. Pal'shin, P. Oleynik, M. Ulanov, D. Svinkin, and T. Cline, on behalf of the Konus-Wind team, report: The long-duration intense GRB 130609B (Swift-BAT trigger 557828: Krimm, et al., GCN 14841) triggered Konus-Wind at T0=77916.818 s UT (21:38:36.818) The light curve consists of two major emission episodes: the first one with a bright multi-peaked structure from ~T0-30 s to ~T0+55 s, and the second, much weaker and softer episode, from ~T0+170 s to ~T0+210 s. The emission is seen up to 7 MeV. The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB130609_T77916/ As observed by Konus-Wind, the burst had a fluence of (9.4 ± 0.7)x10-5 erg/cm2, and a 64-ms peak flux, measured from T0+3.712 s, of (9.5 ± 0.6)x10-6 erg/cm2/s (both in the 20 keV - 10 MeV energy range). The time-averaged spectrum of the first emission episode (measured from T0 to T0+54.528 s) is best fit in the 20 keV - 18 MeV range by the GRB (Band) function with the following model parameters: the low-energy photon index alpha = -0.84 ± 0.05, the high energy photon index beta = -2.39 ± 0.15, the peak energy Ep = 397 ± 26 keV, chi2 = 97/97 dof. The time-averaged spectrum of the second emission episode (measured from T0+169.216 to T0+210.176 s) is best fit in the 20 keV - 18 MeV range by the cutoff power law with the following model parameters: the photon index alpha = -1.64 ± 0.21, the peak energy Ep = 198 ± 105 keV, chi2 = 93.7/98 dof. The spectrum at the maximum count rate (measured from T0 to T0+6.656 s) is best fit in the 20 keV - 18 MeV range by the GRB (Band) function with the following model parameters: the low-energy photon index alpha = -0.70 ± 0.07, the high energy photon index beta = -3.0 ± 0.3, the peak energy Ep = 740 ± 90 keV, chi2 = 105/97 dof. All the quoted results are preliminary. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 14857 SUBJECT: GRB 130609B: Swift/UVOT Observations DATE: 13/06/10 16:46:41 GMT FROM: Mike Siegel at PSU/Swift MOC M. H. Siegel (PSU) and H. A. Krimm (CRESST/GSFC/USRA) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 130609B 85 s after the BAT trigger (Krimm et al., GCN Circ. 14841). A fading source consistent with the XRT position (Goad et al. GCN Circ. 14847) is detected in the initial UVOT exposures. The preliminary UVOT position is: RA (J2000) = 03:35:05.11 = 53.77128 (deg.) Dec (J2000) = -40:10:26.7 = -40.17409 (deg.) with an estimated uncertainty of 0.50 arc sec. (radius, 90% confidence). Preliminary detections and 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first and second orbit exposures are: Filter T_start(s) T_stop(s) Exp(s) Mag white (fc) 84 234 147 15.47+-0.02 white 577 1891 283 17.36+-0.03 white 6046 7681 393 18.39+-0.05 v 799 1941 136 16.89+-0.09 v 6457 6657 196 18.00+-0.15 b 552 1866 136 17.32+-0.06 b 5841 7476 393 18.46+-0.09 u (fc) 297 546 245 16.31+-0.04 u 700 1841 116 17.15+-0.08 u 5636 7271 393 18.15+-0.09 uvw1 676 1816 136 17.61+-0.12 uvw1 5432 7067 393 18.75+-0.15 uvm2 823 1791 116 19.12+-0.35 uvm2 6662 6861 196 >19.66 uvw2 603 1916 116 >19.51 uvw2 6252 7855 362 >20.39 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.01 in the direction of the burst (Schlegel et al. 1998). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 14862 SUBJECT: GRB 130609B, Swift-BAT refined analysis DATE: 13/06/10 21:39:05 GMT FROM: Hans Krimm at NASA-GSFC A. Y. Lien (NASA/GSFC/ORAU), 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), D. M. Palmer (LANL), T. Sakamoto (AGU), 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 130609B (trigger #557828) (Krimm, et al., GCN Circ. 13841). The BAT ground-calculated position is RA, Dec = 53.776, -40.168 deg which is RA(J2000) = 03h 35m 06.2s Dec(J2000) = -40d 10' 04.0" with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment). The partial coding was 43%. The mask-weighted light curve shows an initial complex of two main overlapping peaks with numerous subsidiary peaks, with strong emission between T-10 and T+50 sec and low-level emission between T-30 and T+120 sec. The highest points are at T+4 and T+18 sec. Then there is a second, weaker and softer pair of overlapping peaks between T+160 sec and T+220 sec. This second set of peaks is consistent with a flare seen in the Swift-XRT. T90 (15-350 keV) is 191.98 +- 2.44 sec (estimated error including systematics) We note that receipt of the full event data for GRB 130609B may reveal further late-time peaks and require a revision of the T90 estimate. We will report on the full data set in a later Circular. The time-averaged spectrum from T-7.84 to T+213.25 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.23 +- 0.04. The fluence in the 15-150 keV band is 1.6 +- 0.0 x 10^-05 erg/cm2. The 1-sec peak photon flux measured from T+16.78 sec in the 15-150 keV band is 8.5 +- 0.4 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/557828/BA/ //////////////////////////////////////////////////////////////////////// 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: 14866 SUBJECT: GRB 130609B: GROND observations DATE: 13/06/11 13:16:42 GMT FROM: Andrea Rossi at TLS Tautenburg S. Schmidl, A. Rossi (both TLS Tautenburg), and J. Greiner (MPE Garching) report on behalf of the GROND team: We observed the field of GRB 130609B (Swift trigger 557828; Krimm et al., GCN #14841) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, PASP 120, 405) mounted at the 2.2 m MPG/ESO telescope at La Silla Observatory (Chile). Observations started at 09:30 UT on 11th June 2013, 35.9 hours after the GRB trigger. They were performed at an average seeing of 1.6" and at an average airmass of 2.2. We detect a source at the position of the UVOT afterglow (Siegel et al.; GCN #14857), and based on images taken at a mid-time of 09:45 UT, with total exposures of 25 minutes in g'r'i'z' and 20 minutes in JHK, we estimate preliminary magnitudes (all in AB) of g' = 22.2 +/- 0.1 mag, r' = 21.7 +/- 0.1 mag, i' = 21.1 +/- 0.2 mag, z' = 20.9 +/- 0.2 mag, J = 20.6 +/- 0.3 mag, H = 19.8 +/- 0.4 mag, and K = 19.4 +/- 0.4 mag. The source is brighter than what one could expect extrapolating the early UVOT data (Siegel et al.; GCN #14857) and could be either a plateau/flare, or due to the contribution of the host galaxy. Given magnitudes are calibrated against GROND zeropoints as well as 2MASS field stars and are not corrected for the expected Galactic foreground extinction corresponding to a reddening of E_(B-V)=0.01 mag in the direction of the burst (Schlegel et al. 1998). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 14867 SUBJECT: GRB 130609B, Further Swift-BAT refined analysis DATE: 13/06/11 13:22:03 GMT FROM: Hans Krimm at NASA-GSFC H. A. Krimm (GSFC/USRA) and J. R. Cummings (GSFC/UMBC) for the Swift-BAT team: Using the full data set from T-239 to T+963 sec from the recent telemetry downlink, we report final analysis of BAT GRB 130609B (trigger #557828) (Krimm, et al., GCN Circ. 14841; Lien at al., GCN Circ. 14862). In addition to the peaks described in Lien at al., GCN Circ. 14862, we report that there is a small peak in the BAT at around T+270 sec, coincident with a second flare in the XRT. T90 (15-350 keV) is 210.6 +- 15.1 sec (estimated error including systematics). The time-averaged spectrum from T-7.8 to T+307.6 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.32 +- 0.04. The fluence and peak photon flux are as reported in GCN Circ. 14862. The quoted error is at the 90% confidence level. The results of the batgrbproduct analysis are available at http://gcn.gsfc.nasa.gov/notices_s/557828/BA/ //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 14869 SUBJECT: GRB 130609B: Fermi GBM observation DATE: 13/06/11 14:52:13 GMT FROM: Veronique Pelassa at UAH V. Pelassa (UAH) reports on behalf of the Fermi GBM Team: "At 21:38:35.61 UT on 09 June 2013, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 130609B (trigger 392506718 / 130609902), which was also detected by the Swift/BAT (H.A. Krimm et al. 2013, GCN 14841). The GBM on-ground location is consistent with the Swift position. The angle from the Fermi LAT boresight is 117 degrees. The GBM light curve consists of two bright peaks within 30s of trigger and a fainter bump at 170s after trigger with a duration (T90) of about 191 s (50-300 keV). The time-averaged spectrum from T0+0.003s to T0+28.672s is well fit by a power law function with an exponential high-energy cutoff. The power law index is -0.70 +/- 0.02 and the cutoff energy, parameterized as Epeak, is 536 +/- 18 keV (Castor statistics 474 for 365 d.o.f.). The event fluence (10-1000 keV) in this time interval is (6.02 +/- 0.07)E-05 erg/cm^2. The 1.024-sec peak photon flux measured starting from T0+6.592 s in the 10-1000 keV band is 13.6 +/-0.4 ph/s/cm^2. A Band function fits the spectrum equally well (Castor statistics 468 for 364 d.o.f.) with Epeak= 491 +/- 20 keV, alpha = -0.66 +/- 0.02 and beta = -2.6 +/- 0.2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog." //////////////////////////////////////////////////////////////////////// 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). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 14888 SUBJECT: GRB 130609B: Theoretical redshift estimation DATE: 13/06/12 18:57:55 GMT FROM: Remo Rufinni at ICRA R. Ruffini, C.L. Bianco, M. Enderli, M. Muccino, A.V. Penacchioni, G.B. Pisani, J.A. Rueda, N. Sahakyan, Y. Wang, L. Izzo report: The late X-ray observations of GRB 130609B evidences a pattern typical of a family of GRBs associated to Supernovae following the Induced Gravitational Collapse (IGC) paradigm. We estimate a cosmological redshift for the GRB of approximately z=1.3. We encourage observations. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 14915 SUBJECT: GRB 130609B: Suzaku WAM observation of the prompt emission DATE: 13/06/18 02:17:01 GMT FROM: Masanori Ohno at Hiroshima U K. Takaki, M. Ohno, T. Kawano, R. Nakamura, S. Furui, Y. Fukazawa (Hiroshima U.), M. Tashiro, Y. Terada, T. Yasuda, Y. Ishida, H. Ueno, S. Sugimoto (Saitama U.), K. Yamaoka (Nagoya U.), M. Yamauchi, M. Akiyama, N. Ohmori (Univ. of Miyazaki), S. Sugita (Ehime U.), Y. E. Nakagawa, M. Kokubun, T. Takahashi (ISAS/JAXA), W. Iwakiri(RIKEN), Y. Hanabata (ICRR), Y. Urata (NCU), K. Nakazawa, K. Makishima (Univ. of Tokyo) on behalf of the Suzaku WAM team, report: The long GRB 130609B (Krimm et al., GCN14841) triggered by the Suzaku Wide-band All-sky Monitor (WAM) which covers an energy range of 50 keV - 5 MeV at 21:38:35 UT (=T0). The observed light curve shows a multi-peaked structure starting at T0, ending at T0+30 s with a duration (T90) of about 19.6 seconds. The fluence in 100 - 1000 keV was 3.77 (+0.24/-0.70) x10^-5 erg/cm^2. The 1-s peak flux measured was 7.03 (+0.39/-2.80) photons/cm^2/s in the same energy range. Preliminary result shows that the time-averaged spectrum from T0 to T0+30 s is well fitted by a power-law with exponential cutoff model: dN/dE ~ E^{-alpha} * exp(-(2-alpha)*E/Epeak) with alpha 1.48 (+0.40/-0.41), and Epeak 845 (+179/-147) keV (chi^2/d.o.f. = 15.2/24). Due to the brightness of this burst, a 5% systematic error was added for low energy channels. All the quoted errors are at statistical 90% confidence level. The light curves for this burst will be available at: http://www.astro.isas.jaxa.jp/suzaku/HXD-WAM/WAM-GRB/grb/trig/grb_table.html