//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 14735 SUBJECT: GRB 130603B: Swift detection of a bright short burst DATE: 13/06/03 16:15:25 GMT FROM: David Palmer at LANL A. Melandri (INAF-OAB), W. H. Baumgartner (GSFC/UMBC), D. N. Burrows (PSU), J. R. Cummings (NASA/UMBC), N. Gehrels (NASA/GSFC), C. Gronwall (PSU), K. L. Page (U Leicester), D. M. Palmer (LANL), R. L. C. Starling (U Leicester) and T. N. Ukwatta (MSU) report on behalf of the Swift Team: At 15:49:14 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 130603B (trigger=557310). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 172.209, +17.045 which is RA(J2000) = 11h 28m 50s Dec(J2000) = +17d 02' 42" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a single spike structure with a duration of about 0.4 sec. The peak count rate was 60000 counts/sec (15-350 keV), at ~0 sec after the trigger. The XRT began observing the field at 15:50:12.8 UT, 59.0 seconds after the BAT trigger. Using promptly downlinked data we find an uncatalogued X-ray source with an enhanced position: RA, Dec 172.2006, 17.0719 which is equivalent to: RA(J2000) = 11h 28m 48.16s Dec(J2000) = +17d 04' 18.8" with an uncertainty of 2.7 arcseconds (radius, 90% containment). This location is 101 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. A power-law fit to a spectrum formed from promptly downlinked event data gives a column density in excess of the Galactic value (1.93 x 10^20 cm^-2, Kalberla et al. 2005), with an excess column of 6.8 (+4.00/-3.31) x 10^21 cm^-2 (90% confidence). UVOT took a finding chart exposure of 150 seconds with the White filter starting 62 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 25% of the BAT error circle. The typical 3-sigma upper limit has been about 19.6 mag. The 8'x8' region for the list of sources generated on-board covers 100% of the BAT 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 0.02. The Swift star trackers were not locked at the time of the burst, so there may be some additional error in the position. However the spike in the rates and the image detection is unambiguously real. We note that this bright short hard GRB is near (12 arcminutes) the location of the nearby galaxy NGC 3691. At z=0.003566, this corresponds to a nominal projected distance of about 50 kpc. Burst Advocate for this burst is A. Melandri (andrea.melandri AT brera.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: 14739 SUBJECT: GRB 130603B: Enhanced Swift-XRT position DATE: 13/06/03 21:45:08 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 712 s of XRT Photon Counting mode data and 1 UVOT images for GRB 130603B, 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 = 172.20070, +17.07112 which is equivalent to: RA (J2000): 11h 28m 48.17s Dec (J2000): +17d 04' 16.0" with an uncertainty of 2.0 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: 14741 SUBJECT: GRB 130603B: Swift-BAT refined analysis DATE: 13/06/03 22:16:10 GMT FROM: Scott Barthelmy at NASA/GSFC S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), A. Y. Lien (NASA/GSFC/ORAU), C. B. Markwardt (GSFC), A. Melandri (INAF-OAB), 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-61 to T+242 sec from the recent telemetry downlink, we report further analysis of BAT GRB 130603B (trigger #557310) (Melandri, et al., GCN Circ. 14735). The BAT ground-calculated position is RA, Dec = 172.222, 17.063 deg, which is RA(J2000) = 11h 28m 53.2s Dec(J2000) = +17d 03' 48.2" with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment). The partial coding was 100%. The mask-weighted light curve shows a single FRED-like spike starting at ~T_0.000, peaking at ~T+0.012 sec, and returning to baseline at~T+0.2sec. There is a smaller pulse ridding on the tail of the initial pulse. T90 (15-350 keV) is 0.18 +- 0.02 sec (estimated error including systematics). The time-averaged spectrum from T+0.01 to T+0.26 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 0.82 +- 0.07. The fluence in the 15-150 keV band is 6.3 +- 0.3 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T-0.36 sec in the 15-150 keV band is 6.4 +- 0.3 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/557310/BA/ //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 14742 SUBJECT: GRB 130603B: WHT optical afterglow candidate DATE: 13/06/03 22:53:37 GMT FROM: Andrew Levan at U.of Leicester A.J. Levan (U. Warwick), N.R. Tanvir, K. Wiersema (U. Leicester), O. Hartoog (Amsterdam), K. Kolle, J. Mendez (ING) and T. Kupfer (Nijmegan) report for a larger collaboration: We observed the location of GRB 130603B (Melandri et al. GCN 14735) with the William Herschel Telescope, beginning at 21:39 UT approximately 5.8 hours after the burst. In our z and r-band observations we identify a galaxy present in the SDSS DR9 observations of the field with a magnitude of r=20.94. In addition we identify a point-like source, offset approximately 1" to the SW of this source, with an approximate (+/- 1") position of; RA(J2000) 11 28 48.16 DEC(J2000) +17:04:18.0 This source is blended with the SDSS galaxy, but appears to be brighter. We suggest this is likely to be the optical afterglow of GRB 130603B." //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 14743 SUBJECT: GRB 130603B: Afterglow detection from NOT DATE: 13/06/03 23:31:08 GMT FROM: Antonio de Ugarte Postigo at IAA-CSIC A. de Ugarte Postigo (IAA-CSIC, DARK/NBI), D. Malesani (DARK/NBI), D. Xu (DARK/NBI), P. Jakobsson (U. Iceland), J. Datson (Tuorla Obs.), R. Salinas (FINCA), T. Augusteijn (NOT), Y. Martinez-Osorio (NOT), report on behalf of a larger collaboration: We observed the field of the short GRB 130603B (Melandri et al., GCN 14735) using the 2.5m NOT telescope beginning on 2013 Jun 3 at 21:22 UT. Observations consisted of 5x360 s in the r band. As noted by Levan et al. (GCN 14742), the refined XRT position (Evans et al., GCN 14739) straddles a galaxy detected in the SDSS, which has a photometric redshift z=0.39+/-0.11. Our images reveal a point source superimposed over this galaxy, and consistent with the XRT posion, at the following coordinates (J2000+/-0.5"): R.A.: 11:28:48.15 Dec.: +17:04:18.0 This source is not visible in the SDSS and it is the afterglow of GRB 130603B. We obtain a preliminary magnitude of r = 20.9 calibrated against SDSS (DR9). The afterglow is located ~0.8" SW of the host galaxy nucleus. Our results are consistent with those of Levan et al. (GCN 14742). [GCN OPS NOTE(06jun13): Per author's request, the author list was changed; 1 was dropped and 4 were added.] //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 14744 SUBJECT: GRB 130603B: Short GRB afterglow spectrum from GTC DATE: 13/06/04 00:38:17 GMT FROM: Antonio de Ugarte Postigo at IAA-CSIC C. C. Thöne (IAA-CSIC), A. de Ugarte Postigo (IAA-CSIC/DARK), J. Gorosabel (IAA-CSIC/UPV-EUH), N. Tanvir (U. Leicester), and J. P. U. Fynbo (DARK/NBI) report: We obtained spectroscopy of the afterglow (GCN 14742, Levan et al, GCN 14743, de Ugarte Postigo et al.) of the short GRB 130603B (GCN 14735, Melandri et al.) with OSIRIS/GTC starting at 23:05 UT. Three spectra of 900s were obtained with grism R1000B. The afterglow lies on top of an SDSS galaxy as noted in Levan et al. The spectrum shows a strong trace of the afterglow with absorption lines of the Ca II doublet as well as MgII and MgI. Superimposed are emission lines from the host galaxy of [OII], [OIII], Hbeta and Hgamma extended in the spatial direction. Absorption and emission lines lie at a common redshift of z=0.356. We therefore determine this to be the redshift of the short GRB and its host galaxy. We acknowledge the excellent support by the GTC staff, in particular Rene Rutten and David Garcia. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 14745 SUBJECT: GRB 130603B: Magellan redshift confirmation DATE: 13/06/04 00:49:03 GMT FROM: Ryan Chornock at Harvard R. J. Foley, R. Chornock, W. Fong, E. Berger (Harvard), S. Jha (Rutgers) report: We observed the field of the short-duration GRB 130603B (Melandri et al., GCN 14735) with the Inamori Magellan Areal Camera and Spectrograph (IMACS) mounted on the Magellan/Baade 6.5-m telescope starting on 2013 Jun 04.004 UT (8.3-hr after the BAT trigger). In 600-s of r-band imaging, we detect the optical afterglow and host galaxy (Levan et al., GCN 14742; de Ugarte Postigo et al., GCN 14743). A 1200-s spectrum reveals several nebular emission lines from the host galaxy at a common redshift of 0.356, confirming the results of Thoene et al. (GCN 14744). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 14746 SUBJECT: GRB 130603B: Swift-BAT Spectral lag analysis DATE: 13/06/04 02:39:24 GMT FROM: Scott Barthelmy at NASA/GSFC J. Norris (BSU), N. Gehrels (GSFC), S. D. Barthelmy (GSFC), T. Sakamoto (AGU) We report the spectral lag analysis for GRB 130603B (GCN Circ. 14735 & 14740) based on the BAT data. Using 2-ms binned light curves, the spectral lag for the 15-25 keV to 50-100 keV bands is 0.6 +-0.7 ms, and -2.5 +-0.7 mc for the 25-50 keV to 100-350 keV bands for both peaks combined. These lag values and the hard spectrum (GCN Circ. 14741) place this burst in the short burst category. There is no evidence for extended emission at the 0.005 cnts/det/sec level. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 14747 SUBJECT: GRB 130603B: optical follow-up and independent GTC redshift determination and afterglow spectrum DATE: 13/06/04 03:05:17 GMT FROM: Alberto Castro-Tirado at Inst.de Astro. de Andalucia R. Sánchez-Ramírez, A. J. Castro-Tirado (IAA-CSIC), J. Gorosabel (IAA-CSIC, UPV-EHU), F. J. Aceituno (IAA-CSIC), E. Sonbas (Adiyaman Univ.), E. Gogus, T. Güver (Sanbaci Univ.), H. Kirbiyik (TUG) and D. García-Alvárez (GTC) on behalf of a larger collaboration, report: “We have observed the optical afterglow of the short-duration GRB 130603B (Melandri et al. GCNC 14735, Norris et al. GCNC 14746). Optical images have been obtained with the 1.0m telescope at the Tübitak National Observatory (Antalya, Turkey) in the R-band and with the 1.5m telescope at Observatorio de Sierra Nevada (Granada, Spain) in the I-band, starting on June 3. 771 and June 3.854 UT (2.69 hr and 4.69 hr post burst) respectively. Spectra covering the range 3500-10000 A were obtained with the 10.4m GTC (+OSIRIS) starting on June 3.993 UT (i.e. 8 hr post burst). At the position of the optical afterglow (Levan et al. GCNC 14742) the afterglow spectrum shows Ca II in absorption, and we detect significant contribution of the underlying host galaxy (eg. [OII], [OIII], H-beta and H-alpha emission lines about 1” off), implying altogether a redshift of z = 0.356, consistent with the values provided by Thoene et al. (GCNC 14744) and Foley et al. (GCNC 14745)“. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 14748 SUBJECT: GRB 130603B: Gemini Observations DATE: 13/06/04 03:11:31 GMT FROM: Antonino Cucchiara at UCSC/UCO Lick A. Cucchiara (UCSC/UCO Lick), D. Perley (Caltech), and S. B. Cenko (GSFC) report on behalf of a larger collaboration: On June 3.97 UT we start observing the optical afterglow of the Short GRB 130603B (Melandri et al. GCN 14735, Evans et al., GCN 14739, Levan et al. GCN 14742, and de Ugarte Postigo et al. GCN 14743) with the Gemini-South telescope equipped with the GMOS camera. The observation sequence consists of a series of 8x3min exposures in the g',r' and i' filters. The OT is clearly detected in individual exposures. Using the coadded frames and a 0.7" aperture, we estimate the following magnitudes: g = 21.7 +/- 0.2 r = 21.2 +/- 0.1 i = 20.7 +/- 0.2 These are not corrected for Galactic extinction or for contribution of the host galaxy, which is likely significant. An RGB image of the field showing the optical transient has been posted to: http://www.astro.caltech.edu/~dperley/gcn/130603b/130603b_gmos.png Also, a spectroscopic sequence was obtained: based on CaHK lines and several emission lines we confirm the redshift of GRB 130603B to be z=0.356 (as also reported by Thoene et al. GCN. 14744, Foley et al. 14745). We thank the Gemini South Staff, in particular A. Cardwell, J. Turner and Mischa Schirmer, for the excellent support. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 14749 SUBJECT: GRB 130603B: Swift-XRT refined Analysis DATE: 13/06/04 04:15:04 GMT FROM: Phil Evans at U of Leicester J.A. Kennea (PSU), M.C. Stroh (PSU), D.N. Burrows (PSU), A.P. Beardmore (U. Leicester), P.A. Evans (U. Leicester), B.P. Gompertz (U. Leicester), G. Stratta (ASDC), P. D'Avanzo (INAF-OAB), V. D'Elia (ASDC) and A. Melandri report on behalf of the Swift-XRT team: We have analysed 6.6 ks of XRT data for GRB 130603B (Melandri et al. GCN Circ. 14735), from 43 s to 28.2 ks after the BAT trigger. The data comprise 378 s 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 Evans et al. (GCN. Circ 14739). The light curve can be modelled with an initial power-law decay with an index of alpha=0.35 (+0.08, -0.09), followed by a break at T+2404 s to an alpha of 1.46 (+0.13, -0.12). A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 1.97 (+0.23, -0.22). The best-fitting absorption column is 2.8 (+1.0, -0.8) x 10^21 cm^-2, in excess of the Galactic value of 1.9 x 10^20 cm^-2 (Kalberla et al. 2005). The PC mode spectrum has a photon index of 2.21 (+0.18, -0.17) and a best-fitting absorption column of 2.5 (+/-0.5) x 10^21 cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.6 x 10^-11 (6.2 x 10^-11) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Total column: 2.5 (+/-0.5) x 10^21 cm^-2 Galactic foreground: 1.9 x 10^20 cm^-2 Excess significance: 7.7 sigma Photon index: 2.21 (+0.18, -0.17) If the light curve continues to decay with a power-law decay index of 1.46, the count rate at T+24 hours will be 4.7 x 10^-3 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.7 x 10^-13 (2.9 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/00557310. This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 14751 SUBJECT: GRB 130603B: 5.8 GHz VLA detection DATE: 13/06/04 06:57:59 GMT FROM: Wen-fai Fong at CFA W. Fong, B. A. Zauderer and E. Berger (Harvard) report: "We observed the position of the short-duration GRB 130630B (Melandri et al., GCN 14735) with the Karl G. Jansky Very Large Array (VLA) beginning on 2013 June 03.98 UT (7.6 hr post-burst) at a mean frequency of 5.8 GHz. In 1 hour of observations, we detect a ~0.2 mJy radio source in coincidence with the reported optical afterglow (Levan et al., GCN 14742; de Ugarte Postigo et al., GCN 14743; Foley et al., GCN 14745; Cucchiara et al., GCN 14748). We note that this is only the fourth detection of radio emission from a short GRB, of which one case (GRB 120804A; Berger et al., 2013, ApJ, 765, 121) was due to host galaxy emission. Further observations are planned. We thank the VLA staff for quickly executing these observations." //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 14757 SUBJECT: GRB 130603B: VLT/X-shooter redshift confirmation DATE: 13/06/04 10:38:37 GMT FROM: Dong Xu at DARK/NBI D. Xu (DARK/NBI), A. de Ugarte Postigo (IAA-CSIC, DARK/NBI), D. Malesani (DARK/NBI), S. Schulze (PUC and MCSS), J. P. U. Fynbo, D. J. Watson (DARK/NBI), V. D'Elia (ASI-SDC, INAF OAR), P. Goldoni (APC, CEA/Irfu), M. Vestergaard (DARK/NBI) report on behalf of the X-shooter GRB GTO collaboration: We observed the optical afterglow of the short-duration GRB 130603B (Melandri et al., GCN 14735; Levan et al., GCN 14742; de Ugarte Postigo et al., GCN 14743) using the ESO VLT equipped with the X-shooter spectrograph. The observations started on 2013-06-04 at 00:00:28 UT (i.e., 8.187 hr after the burst). A total exposure of 4x600 s was obtained, covering the spectral range from ~300 to ~2100 nm. A continuum is detected in all the UVB/VIS/NIR arms of the spectra. We identify several absorption features which we interpret as Ca II H & K and Mg II from the optical afterglow, as well as emission lines such as the [O II] doublet, [O III], H-alpha, H-beta, and [S II] from the host galaxy, all at a common redshift of z=0.3564+/-0.0002, fully consistent with the measurements by Thoene et al. (GCN 14744), Foley et al. (GCN 14745), and Sanchez-Ramirez et al. (GCN 14747). We thank the Paranal staff for enthusiastic support, in particular Cedric Ledoux and Alex Correa. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 14759 SUBJECT: GRB130603B: Swift/UVOT detection DATE: 13/06/04 11:59:05 GMT FROM: Massimiliano de Pasquale at MSSL-UCL M. De Pasquale (MSSL-UCL) and A. Melandri (INAF-OAB) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 130603B 62 s after the BAT trigger (Melandri et al., GCN Circ. 14735). A source 2'' from the centre of the XRT error circle (Evans et al. GCN Circ. 14739) and coincident with the optical afterglow detected by WHT (Levan et al., GCN circ. 14742) and NOT (de Ugarte Postigo et al., GCN circ. 14743) is detected in UVOT exposures. The source, in UVOT images, shows no clear fading behaviour between the first and the latest exposures. Preliminary detections and 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early exposures are: Filter T_start(s) T_stop(s) Exp(s) Mag white 62 4981 383 20.81 ±0.17 v 605 5393 225 >19.8 b 530 6212 432 21.14 ±0.45 (2.5 sigma) u 275 6007 659 20.87 ±0.39 (2.8 sigma) w1 654 5802 413 >20.6 m2 3960 5597 393 >20.4 w2 580 6555 365 20.69 ±0.39 (2.8 sigma) The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.02 in the direction of the burst (Schlegel et al. 1998). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 14761 SUBJECT: GRB 130603B: P60 Observations DATE: 13/06/04 15:54:39 GMT FROM: S. Bradley Cenko at Caltech S. B. Cenko (GSFC) and D. A. Perley (Caltech) report on behalf of a larger collaboration: We have imaged the field of the short-hard GRB 130603B (Melandri et al., GCN 14735) with the robotic Palomar 60 inch telescope. Images were obtained in the r' and i' filters beginning at 04:00 on 2013 June 4 (~ 12.2 hr after the Swift trigger). At the location of the optical afterglow (Levan et al., GCN 14742), we detect a source mildly blended with the presumed host galaxy. Using a large aperture to include both objects, we measure a magnitude of r' = 20.8 at this time (calibrated with respect to several nearby point sources from SDSS). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 14764 SUBJECT: GRB 130603B: RATIR Optical and NIR Observations DATE: 13/06/04 17:49:36 GMT FROM: Eleonora Troja at GSFC Eleonora Troja (GSFC), 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), 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 130603B (Melandri, et al., GCN 14735) 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 4.16 to 2013/06 4.27 UTC (12.01 to 14.78 hours after the BAT trigger), obtaining a total of 1.93 hours exposure in the r' and i' bands and 0.81 hours exposure in the Z, Y, J, and H bands. At the location of the optical afterglow (Levan et al., GCN 14742), in comparison with SDSS DR8 and 2MASS, we obtain the following detections: r' 20.78 +/- 0.03 i' 20.52 +/- 0.03 Z 20.20 +/- 0.05 Y 19.94 +/- 0.05 J 19.97 +/- 0.06 H 19.55 +/- 0.06 These magnitudes are in the AB system and not corrected for Galactic extinction in the direction of the GRB. Photometry was performed adopting a large aperture which includes both the afterglow and its host galaxy. We thank the staff of the Observatorio Astronómico Nacional in San Pedro Mártir. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 14769 SUBJECT: GRB 130603B: AMI-LA 15GHz observations DATE: 13/06/05 11:38:07 GMT FROM: Tim Staley at U of Southampton T.D. Staley, G.E. Anderson, R.P. Fender (U. of Southampton), A. Rowlinson, A.J. van der Horst (U. of Amsterdam), D.J. Titterington, C. Rumsey (MRAO) report on behalf of the 4 Pi Sky / AMI team: We have observed the position of the GRB 130603B afterglow at multiple epochs with the AMI Large Array at 15 GHz. Our initial observation was for one hour starting at 15:53:42 UT on June 3rd, just under 5 minutes after the GRB trigger time (GCN 14735). We also made longer observations, at 3.12 and 22.8 hours post-burst. We do not detect the afterglow in our preliminary reductions. Preliminary analysis gives 3-sigma upper limits as follows: Start (Hrs post burst) | Duration (hrs) | 3-sigma upper limit --------------------------------------------------------------------- 0.08 | 1 | 0.6 mJy 3.12 | 3 | 0.21 mJy 22.8 | 3 | 0.3 mJy Further observations are scheduled. These observations were initially triggered via the system described in Staley et. al (2013, MNRAS, 428, 3114). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 14770 SUBJECT: GRB 130603B: MASTER-Net early observations and optical sloap limit DATE: 13/06/05 17:11:24 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs Maria Pruzhinskaya, D.Denisenko, E. Gorbovskoy, V. Lipunov, V.Kornilov, D.Kuvshinov, N.Tyurina, N.Shatskiy, P.Balanutsa, D.Zimnukhov, A.Kuznetsov, V.V.Chazov Sternberg Astronomical Institute, Lomonosov Moscow State University K.Ivanov, S.Yazev, N.M.Budnev, O.Gres, O.Chuvalaev, V.A.Poleshchuk Irkutsk State University, Irkutsk V.Yurkov, Yu.Sergienko, D.Varda, E.Sinyakov, A.Gabovich Blagoveschensk Educational State University, Blagoveschensk A. Tlatov, A.V. Parhomenko, D. Dormidontov, V.Sennik Kislovodsk Solar Station of the Pulkovo Observatory V.Krushinski, I.Zalozhnih, A. Popov Ural Federal University, Kourovka Hugo Levato and Carlos Saffe Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE) Claudio Mallamaci, Carlos Lopez and Federico Podest Observatorio Astronomico Felix Aguilar (OAFA) MASTER II robotic telescope (MASTER-Net: http://observ.pereplet.ru) located in Tunka was pointed to GRB130603B 35 sec after Notice time and 52 sec after Trigger time (Melandri et al., GCN 14735) in two mutually perpendicular polarizations. We didn't find OT at the position reported by Levan et al., GCN 14742 and A. de Ugarte Postigo et al., GCN 14743. Our photometry (upper limits) during the first 20 minutes until the clouds started coming in is as follows: t_UT Exp T-T_trig Limit Filter Tube ------------------------------------------------------- 2013-06-03 15:50:06 10 52 15.4 P| EAST 2013-06-03 15:50:07 10 53 15.1 P- WEST 2013-06-03 15:51:06 20 112 15.9 P| EAST 2013-06-03 15:51:07 20 113 15.8 P- WEST 2013-06-03 15:52:08 30 174 16.2 P| EAST 2013-06-03 15:52:08 30 174 16.1 P- WEST 2013-06-03 15:53:18 50 244 16.7 P| EAST 2013-06-03 15:53:19 50 245 16.7 P- WEST 2013-06-03 15:55:01 70 348 16.7 P| EAST 2013-06-03 15:55:02 70 349 16.6 P- WEST 2013-06-03 15:56:48 90 454 17.2 P| EAST 2013-06-03 15:56:49 90 455 16.9 P- WEST 2013-06-03 15:58:57 120 583 17.6 P| EAST 2013-06-03 15:58:58 120 584 17.5 P- WEST 2013-06-03 16:01:43 150 749 18.0 P| EAST 2013-06-03 16:01:43 150 749 17.6 P- WEST 2013-06-03 16:04:54 180 940 18.0 P| EAST 2013-06-03 16:04:54 180 940 17.5 P- WEST The OT upper limit available on the plot : http://master.sai.msu.ru/static/OT/grb130306B.gif We have tried to compare our data with the photometry from the large telescopes in the filters similar to ours. In fact, we have used the observations in r filter. The following data have been published so far. Afterglow: t+5.8 hours r=20.94 WHT Levan et al., GCN 14742 t+5.8 hours r=20.9 NOT A. de Ugarte Postigo et al., GCN 14743 t+7.5 hours r=21.2 Gemini-South Cucchiara et al., GCN 14748 Large aperture to include both objects: t+12.2 hours r'=20.8 P60 (Palomar 60 inch) Cenko et al., GCN 14761 t+14.78 hours r'=20.78 RATIR (1.5m Harold Johnson) Eleonora Troja et al., GCN 14764 We were not able to use the Swift UVOT data in the white light (De Pasquale et al., GCN 14759) since their exact times of mid-exposures are not easy to determine. Obviously, the last two points involve the host galaxy. In order to constrain the slope we have used the data from WHT, NOT and Gemini South. The results are presented here: http://master.sai.msu.ru/static/OT/grb130306B_all.gif Thus, supposing the power law of the fading afterglow F ~ t^-alpha we are providing the following limitation: alpha < 0.84. The message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 14771 SUBJECT: Konus-Wind observation of GRB 130603B DATE: 13/06/05 17:33:26 GMT FROM: Dmitry Frederiks at Ioffe Institute S. Golenetskii, R.Aptekar, D. Frederiks, E. Mazets, V. Pal'shin, P. Oleynik, M. Ulanov, D. Svinkin, and T. Cline on behalf of the Konus-Wind team, report: The bright short-duration hard GRB 130603B (Swift-BAT trigger 557310: Melandri, et al., GCN 14735; Barthelmy et al., GCN 14741) triggered Konus-Wind at T0=56956.448s UT (15:49:16.448) The light curve shows a multi-peaked structure from ~T0-0.008 s to ~T0+0.082 s. The total duration of the burst is ~0.090 s The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB130603_T56956/ As observed by Konus-Wind, the burst had a fluence of (6.6 ± 0.7)x10-6 erg/cm2, and a 16-ms peak flux, measured from T0, of (1.0 ± 0.2)x10-4 erg/cm2/s (both in the 20 keV - 10 MeV energy range). The spectrum of the burst (measured from T0 to T0+0.128 s) is best fit in the 20 keV - 15 MeV range by the cutoff power law with the following model parameters: the photon index alpha = -0.73 ± 0.15, the peak energy Ep = 660 ± 100 keV, chi2 = 67/69 dof. All the quoted results are preliminary. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 14772 SUBJECT: GRB 130603B: rest-frame energegics in gamma-rays DATE: 13/06/05 18:10:23 GMT FROM: Dmitry Frederiks at Ioffe Institute D. Frederiks, on behalf of the Konus-Wind team, report: Assuming z=0.356 (Thöne et al., GCN 14744), and a standard cosmology model with H_0 = 70 km/s/Mpc, Omega_M = 0.27, and Omega_Lambda = 0.73, we estimate the following rest-frame parameters of GRB 130603B from the Konus-Wind observation of the burst (Golenetskii et al., GCN 14771): the isotropic energy release E_iso is (2.1 ± 0.2)x10^51 erg, the peak luminosity (L_iso)_max is (4.4 ± 0.8)x10^52 erg/s, and the rest-frame peak energy Ep,i = (900 ± 140) keV //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 14865 SUBJECT: GMRT radio observation of GRB 130603B DATE: 13/06/11 07:16:47 GMT FROM: Poonam Chandra at TIFR Poonam Chandra (NCRA-TIFR) reports: We carried out Giant Metrewave Radio Telescope (GMRT) observations of GRB 130427A at 1390 GHz band on 2013 June 07.38 UT. We don't detect the GRB in our radio observations. The 3-sigma upper limit at the GRB afterglow position (Levan et al., GCN 14742; de Ugarte Postigo et al., GCN 14743; Foley et al., GCN 14745; Cucchiara et al., GCN 14748) is 273 uJy. We thank GMRT staff for making these observations possible. -- ********************************************************************** Poonam Chandra Phone: +91 20 2571 9290 Tata Institute of Fundamental Research Email: poonam@ncra.tifr.res.in National Center for Radio Astrophysics Home: ncra.tifr.res.in/~poonam Post Bag 3, Pune University campus Ganeshkhind, Pune 411 008, INDIA //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 14893 SUBJECT: GRB 130603B: HST limits on an underlying supernova DATE: 13/06/13 21:18:52 GMT FROM: Nial Tanvir at U.Leicester N. R. Tanvir (U. Leicester), A. J. Levan (U. Warwick), A. S. Fruchter (STScI), J. Hjorth (DARK/NBI) and K. Wiersema (U. Leicester) report: We observed the location of GRB 130603B with HST/ACS and WFC3/IR. The host galaxy is clearly resolved as a disturbed spiral, and it appears that the GRB occurred close to a spiral arm that seems to have been tidally distorted or drawn out by interaction with a smaller neighbour. Our provisional analysis finds a point-source limit of F606W>27.6, corresponding to M_V~-14.3, at the location of the GRB. This is approaching a factor ~100 below what would be expected if there were a rising supernova comparable to SN1998bw, ruling out such an association for this burst. It also rules out some part of the parameter space of other radioactively-powered transients that have been proposed may accompany short GRBs. The position of the GRB lands on a region of extended emission in the F160W (H') filter of WFC3/IR. Another epoch scheduled for a few weeks from now will allow a deeper search for a counterpart through image subtraction. We thank the STScI director and staff for rapidly expediting these observations. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 14895 SUBJECT: GRB 130603B: Detection of possible afterglow/kilonova in HST observations DATE: 13/06/14 04:35:26 GMT FROM: Edo Berger at Harvard E. Berger and W. Fong (Harvard) report: "We obtained the public Hubble Space Telescope ACS/F606W and WFC3/F160W images of GRB 130603B (Tanvir et al. GCN #14893) from MAST and performed an astrometric tie of these images relative to our afterglow images from Magellan/IMACS (Foley et al. GCN #14745). The resulting total rms of the astrometic fit is 33 mas. At the location of the optical afterglow we identify an apparent point source in the WFC3/F160W image, with no corresponding counterpart in the ACS/F606W image (the circles marking the afterglow position have a radius of 10-sigma): https://www.cfa.harvard.edu/~eberger/GRB130603B_HST.tif PSF-matched photometry indicates m(F160W)=25.8+/-0.2 AB mag and m(F606W)>27.5 mag (3-sigma; the limit is consistent with Tanvir et al. GCN #14893). At the redshift of GRB 130603B (z=0.356) these values correspond to absolute magnitudes of M(F160W)=-15.2 mag and M(F606W)>-13.5 mag. The red V-H>1.7 mag color is potentially in good agreement with the afterglow g/r/i colors at early time (8.4 hr), which indicate a spectral index of beta~-1.7 (Cucchiara et al. arXiv:1306.2028). Based on this spectral index and the g/r/i magnitudes from Cucchiara et al., the interpolated/extrapolated magnitudes in the HST filters at 8.4 hr are m(F160W)=20.0 mag and m(F606W)=21.9 mag, or V-H~1.9 mag. Therefore, it is possible that the source detected in WFC3/F160W is the fading afterglow, indicating a decline rate of alpha_NIR~-1.6 between 8.4 hr and 9.4 days. Incidentally, this decline rate is in good agreement with the Swift/XRT decline rate of alpha_X~-1.6 at about 1 hr to 1 day ( http://www.swift.ac.uk/xrt_live_cat/00557310/) Alternatively, the red V-H color and the absolute magnitude of M(F160W)=-15.2 mag can be explained as emission from an r-process powered "kilonova", along the recent models by Barnes & Kasen arXiv:1303.5787. For their fiducial model (with M_ej=0.01 Msun and v_ej=0.1c), the expected absolute magnitude in the rest-frame J-band (corresponding to observed H-band) at an observed time of 9.4 days is about -15 mag, while the expected magnitude in the rest-frame B-band (corresponding to observed V-band) is exceedingly low (about -3 mag). Thus, it is possible that the red source we detected in the WFC3/F160W image represents the first detection of an r-process powered transient associated with a short GRB, thereby strengthening their association with NS-NS/NS-BH mergers. As noted by Tanvir et al. (GCN #14893) additional observations to determine variability are essential." //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 14913 SUBJECT: GRB 130603B: Analogy with GRB 090510A and possible connection with a supernova DATE: 13/06/17 18:22:05 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 report: After a rest-frame time of 5000 sec from the BAT trigger (Melandri et al., GCN 14735), the late X-ray rest-frame luminosity of GRB 130603B overlaps the one of GRB 090510A (see the figure at: ). This match occurs irrespectively of their isotropic energies, which differ by a factor of ~50 (GRB 130603B: E_iso = 2.1 * 10^51 erg, Frederiks et al., GCN 14772; GRB 090510A: E_iso = 1.1 * 10^53 erg, Muccino et al. 2013, ApJ, in press, arXiv:1306.3467). According to Muccino et al. 2013, GRB 090510A is a long GRB exploded in a high density enviroment (10^3 particles/cm^3). The similarity shown in the plot indicates that also GRB 130603B could be a long duration GRB observed at closer distance (z~0.35). Therefore the detection (or not detection) of a supernova associated to GRB 130603B between 20th-23rd of June, becomes a crucial test. Observations are strongly encouraged. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 14922 SUBJECT: GRB 130603B: First epoch of XMM-Newton observations DATE: 13/06/25 01:10:04 GMT FROM: Wen-fai Fong at CFA W. Fong, G. Migliori, R. Margutti, and E. Berger (Harvard) report: "We observed the short-duration GRB 130603B (Melandri et al., GCN 14735) with XMM-Newton + EPIC-pn starting on 2013 June 06.22 UT (2.57 d after the burst) for a total of 24 ksec. We clearly detect the X-ray afterglow at the position of the enhanced XRT error circle (Evans et al., GCN 14739) at a significance level of about 6-sigma. Taken together with the Swift/XRT afterglow light curve for t>4000 sec (Kennea et al., GCN 14749), these observations indicate a single power-law decline with index alpha_X=-1.83+/-0.15. Therefore, the XMM observations rule out the presence of a break at t~4000 sec to 2.57 d, in contrast to the suggested X-ray and optical break at ~8 hr (Tanvir et al., arXiv: 1306.4971)." //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15060 SUBJECT: GRB 130603B: Second epoch of HST WFC/F160W imaging DATE: 13/08/03 11:26:03 GMT FROM: Edo Berger at Harvard W. Fong and E. Berger (Harvard) report: "We inspected the second epoch of HST WFC3/F160W imaging of the short GRB 130603B obtained on 2013 July 3.24 UT. Digital image subtraction relative the first epoch (on 2013 June 13.15 UT) reveals that the near-IR point source coincident with the afterglow position has faded away, confirming our original suggestion that it is associated with GRB 130603B (Berger et al. 2013 arXiv:1306.3960). The subtraction also confirms our brightness measurement, with m(F160W)=25.8 AB mag. Coupled with an early steep decline in the optical band based on additional Magellan/IMACS observations at 32.2 hr post-burst, with r>24.8 AB mag (see also Cucchiara et al. 2013, arXiv:1306.2028; Tanvir et al. 2013, arXiv:1306.4971) this confirms the likely kilonova origin of this source."