//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15627 SUBJECT: GRB 131229A: Swift detection of a burst DATE: 13/12/29 06:55:46 GMT FROM: Scott Barthelmy at NASA/GSFC M. J. Page (UCL-MSSL), S. D. Barthelmy (GSFC), N. Gehrels (NASA/GSFC), H. A. Krimm (CRESST/GSFC/USRA), K. L. Page (U Leicester) and M. H. Siegel (PSU) report on behalf of the Swift Team: At 06:39:24 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 131229A (trigger=582374). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 85.236, -4.431 which is RA(J2000) = 05h 40m 57s Dec(J2000) = -04d 25' 52" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve shows multiple peaks with a total duration of about 25 sec. The peak count rate was ~27,000 counts/sec (15-350 keV), at ~13 sec after the trigger. The XRT began observing the field at 06:40:57.9 UT, 93.8 seconds after the BAT trigger. XRT found a bright, uncatalogued X-ray source located at RA, Dec 85.2327, -4.3962 which is equivalent to: RA(J2000) = +05h 40m 55.85s Dec(J2000) = -04d 23' 46.3" with an uncertainty of 5.0 arcseconds (radius, 90% containment). This location is 125 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. The initial flux in the 2.5 s image was 3.18e-09 erg cm^-2 s^-1 (0.2-10 keV). UVOT took a finding chart exposure of 250 seconds with the U filter starting 158 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 100% of the XRT error circle. The typical 3-sigma upper limit has been about 19.6 mag. No correction has been made for the expected extinction corresponding to E(B-V) of 0.29. Burst Advocate for this burst is M. J. Page (m.page AT ucl.ac.uk). 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: 15628 SUBJECT: GRB 131229A: P60 nondetection DATE: 13/12/29 07:15:30 GMT FROM: Daniel Perley at Caltech D. A. Perley (Caltech) reports on behalf of a larger collaboration: The robotic Palomar 60-inch telescope automatically responded to GRB 131229A (Page et al., GCN 15627) and began a sequence of 60-second image starting at 06:44:54 UT, 5.5 minutes after the burst. In the initial r-band image we identify no sources within the XRT error circle down to a limiting magnitude of R > 20.5. No source in the error circle is detected in the i- or z-band filters either. We do detect a source not present in USNO B1.0 well north of the XRT error circle at RA=05:40:55.702, dec=-04:23:21.11 (J2000). It does not appear to be fading in images taken so far. Further P60 observations are ongoing. NIR observations are encouraged. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15629 SUBJECT: GRB 131229A: KAIT Optical Upper Limit DATE: 13/12/29 07:54:23 GMT FROM: Weikang Zheng at UC Berkeley WeiKang Zheng, Alexei V. Filippenko, Adam Morgan (UC Berkeley), and S. B. Cenko (NASA/Goddard Space Flight Center) report on behalf of the KAIT GRB team: The 0.76-m Katzman Automatic Imaging Telescope (KAIT), located at Lick Observatory, responded to Swift GRB 131229A (Page et al., GCN 15627) starting at 06:41:34 UT, 130 s after the burst. Observations were performed with an automatic sequence in the V, I, and clear(roughly R) filters, and the exposure time was 20 s per image. Compared to the DSS image, we do not detect new sources within XRT error circle. Typical limiting magnitude of our single clear image is about 19.4. We marginally detected the source mentioned by Perley (GCN 15628) in our single clear image with mag around 19.3, and confirming its non-changing brightness. [GCN OPS NOTE(29dec13): Per author's request, the "110 s after the burst" was changed to "130".] //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15630 SUBJECT: GRB 131229A: Deep Gemini-South Imaging DATE: 13/12/29 10:22:22 GMT FROM: Daniel Perley at Caltech D. A. Perley (Caltech), A. Cucchiara (NASA/GSFC), and N. R. Tanvir (U. Leicester) report: We imaged the position of GRB 131229A (Page et al., GCN 15627) using GMOS-S on the Gemini-South 8m telescope in i- an z-bands starting at 07:33:07.5 UT (54 minutes after the GRB). A total of 6 x 180s of imaging was acquired in each filter. Sources detected in the reduced stack inside or close to the (onboard, 5" radius) XRT error circle (with J2000 positions) include: A (05:40:55.85, -04:23:40.6), a point source north of the error circle B (05:40:55.70, -04:23:43.4), an extended source C (05:40:55.92, -04:23:45.9), a faint, marginally detected source No statement about variability or association with the GRB can be made at this time. All of these sources are fainter than the P60 and USNO limits. An image of the field is posted to: http://www.astro.caltech.edu/~dperley/gcn/131229a/131229a_gmos.png //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15631 SUBJECT: GRB 131229A: Enhanced Swift-XRT position DATE: 13/12/29 16:54:35 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 7358 s of XRT Photon Counting mode data and 16 UVOT images for GRB 131229A, 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 = 85.23169, -4.39629 which is equivalent to: RA (J2000): 05h 40m 55.61s Dec (J2000): -04d 23' 46.6" with an uncertainty of 1.4 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: 15633 SUBJECT: GRB 131229A: Swift/UVOT Upper Limits DATE: 13/12/29 18:18:09 GMT FROM: Massimiliano de Pasquale at MSSL-UCL M. De Pasquale (UCL-MSSL) and M. J. Page (UCL-MSSL) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB131229A 159 s after the BAT trigger (Page et al., GCN Circ. 15627). No optical afterglow consistent with the XRT enhanced position (Evans et al. GCN Circ. 15631) is detected in the initial UVOT exposures. Preliminary 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first finding chart (FC) exposure and subsequent exposures are: Filter T_start(s) T_stop(s) Exp(s) Mag u_FC 159 408 246 >19.9 u 159 6481 639 >20.4 v 4434 18141 1889 >20.6 b 4023 16459 2164 >21.6 w1 4844 6275 393 >19.8 w2 4230 17366 1279 >20.5 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.29 in the direction of the burst (Schlegel et al. 1998). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15634 SUBJECT: GRB 131229A: Swift-XRT refined Analysis DATE: 13/12/29 18:56:04 GMT FROM: Phil Evans at U of Leicester A. Maselli (INAF-IASFPA), D.N. Burrows (PSU), J.A. Kennea (PSU), V. Mangano (PSU), C. Pagani (U. Leicester), A.P. Beardmore (U. Leicester), P.A. Evans (U. Leicester), A. Melandri (INAF-OAB), B. Sbarufatti (INAF-OAB/PSU) and M.J. Page report on behalf of the Swift-XRT team: We have analysed 9.9 ks of XRT data for GRB 131229A (Page et al. GCN Circ. 15627), from 80 s to 29.7 ks after the BAT trigger. The data comprise 465 s in Windowed Timing (WT) mode (the first 12 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 15631). The light curve can be modelled with an initial power-law decay with an index of alpha=1.04 (+/-0.06), followed by a break at T+488 s to an alpha of 1.34 (+0.09, -0.06). A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 1.81 (+/-0.07). The best-fitting absorption column is 7.9 (+/-0.5) x 10^21 cm^-2, in excess of the Galactic value of 1.8 x 10^21 cm^-2 (Kalberla et al. 2005). The PC mode spectrum has a photon index of 2.06 (+0.16, -0.15) and a best-fitting absorption column of 8.6 (+1.2, -1.1) x 10^21 cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 5.2 x 10^-11 (1.1 x 10^-10) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Total column: 8.6 (+1.2, -1.1) x 10^21 cm^-2 Galactic foreground: 1.8 x 10^21 cm^-2 Excess significance: 10.4 sigma Photon index: 2.06 (+0.16, -0.15) If the light curve continues to decay with a power-law decay index of 1.34, the count rate at T+24 hours will be 0.010 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 5.2 x 10^-13 (1.1 x 10^-12) erg cm^-2 s^-1. The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00582374. This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15635 SUBJECT: GRB 131229A: Swift-BAT refined analysis DATE: 13/12/29 19:15:46 GMT FROM: Scott Barthelmy at NASA/GSFC T. N. Ukwatta (MSU), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), A. Y. Lien (NASA/UMBC), C. B. Markwardt (GSFC), M. J. Page (UCL-MSSL), D. M. Palmer (LANL), T. Sakamoto (AGU), M. Stamatikos (OSU), J. Tueller (GSFC) (i.e. the Swift-BAT team): Using the data set from T-240 to T+443 sec from recent telemetry downlinks, we report further analysis of BAT GRB 131229A (trigger #582374) (Page, et al., GCN Circ. 15627). The BAT ground-calculated position is RA, Dec = 85.236, -4.401 deg, which is RA(J2000) = 05h 40m 56.6s Dec(J2000) = -04d 24' 04.4" with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment). The partial coding was 97%. The mask-weighted light curve shows many overlapping peaks starting at ~T-1 sec, peaking at ~T+14 sec, and ending at ~T+17 sec with a long low-level tail exteding out to ~T+430 sec, at which point the BAT data stops due to entering the SAA. T90 (15-350 keV) is 13.86 +- 0.43 sec (estimated error including systematics). The time-averaged spectrum from T+0.08 to T+27.04 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.02 +- 0.03. The fluence in the 15-150 keV band is 6.6 +- 0.1 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+13.55 sec in the 15-150 keV band is 10.7 +- 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/582374/BA/ //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15636 SUBJECT: GRB 131229A: GROND observations DATE: 13/12/29 19:23:16 GMT FROM: Patricia Schady at MPE/Swift J. F. Graham, P. Schady, D. A. Kann and J. Greiner (all MPE Garching) report on behalf of the GROND team: We observed the field of GRB 131229A (Page et al., GCN #15627) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, PASP 120, 405) mounted at the 2.2m MPG telescope at La Silla Observatory (Chile). Observations started at 07:02 UT on 29th December, 23 mins after the GRB trigger. They were performed at an average seeing of 1.7" and at high airmass. Source B from Perley et al. (GCN #15630) is clearly detected within a 1440s exposure stacked H-band image (mid-time 07:45UT) with an AB magnitude of 20.1+/-0.2, and marginally detected in z' and J. However, we note that this source lies 1.5" outside the refined XRT position. In 3x8min stacked images centred 53 mins after the trigger, we do not detect a source within the refined Swift-XRT error circle down to the following upper limits (AB magnitudes): g' > 24.2, r' > 24.0, i' > 23.4, z' > 23.2, J > 21.3, H > 20.7, and K > 19.4. The given optical and NIR limits are calibrated against GROND zeropoints and 2MASS field stars in g'r'i'z and JHK respectively, and are not corrected for the Galactic foreground extinction corresponding to a reddening of E(B-V)=0.29 in the direction of the burst (Schlegel et al. 1998). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15637 SUBJECT: GRB 131229A: Magellan upper limit DATE: 13/12/30 07:01:04 GMT FROM: Ryan Chornock at Harvard R. Chornock, W. Fong, and E. Berger (Harvard) report: We observed the field of GRB 131229A (Page et al., GCN 15627) using LDSS3 on the 6.5 m Magellan Clay telescope starting 21 minutes after the BAT trigger. Initial r' and i' images in 0.8" seeing revealed no clear counterpart, consistent with the upper limits reported by other groups (Perley, GCN 15628; Zheng et al., GCN 15629; Perley et al., GCN 15630; Graham et al., GCN 15636; de Pasquale et al., GCN 15633). We then obtained a sequence of 7x180s z'-band images starting at t=+34 min after the trigger. The sources labeled A and B by Perley et al. (GCN 15628) are visible outside of the enhanced XRT error circle (Evans et al., GCN 15631). However, a stack of our images reveals no sources within the enhanced XRT error circle. We set a 3-sigma upper limit of z'>24.3 mag (AB) at a midpoint of t=+49 minutes. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15638 SUBJECT: GRB 131229A: CARMA 3mm observations DATE: 13/12/30 08:02:56 GMT FROM: Daniel Perley at Caltech D. A. Perley (Caltech) reports on behalf of a larger collaboration: We observed the position of GRB 131229A (Page et al., GCN 15627) with the Combined Array for Research in Millimeter Astronomy between 05:39:00 and 07:28:46 UT (0.958-1.034 days post-GRB) at a mean frequency of 93 GHz. Conditions were excellent during the observation. A preliminary examination of the observations reveals no source at the location of the XRT error circle (Evans et al., GCN 15631) down to a limit of approximately 0.6 mJy. We thank the CARMA observers B. A. Zauderer and A. Dhabal and the CARMA staff for assistance with the observation. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15639 SUBJECT: Konus-Wind observation of GRB 131229A DATE: 13/12/31 14:32:55 GMT FROM: Dmitry Svinkin at Ioffe Institute S. Golenetskii, R.Aptekar, D. Frederiks, V. Pal'shin, P. Oleynik, M. Ulanov, D. Svinkin, A. Tsvetkova, and T. Cline on behalf of the Konus-Wind team, report: The long-duration GRB 131229A (Swift-BAT trigger 582374: Page et al., GCN 15627) triggered Konus-Wind at T0=23970.560 s UT (06:39:30.560). The burst light curve shows a multi-peaked structure with a total duration of ~17 s. The emission is seen up to ~1.5 MeV. The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB131229_T23970/ As observed by Konus-Wind, the burst had a fluence of 2.45(-0.17,+0.18)x10-5 erg/cm2, and a 64-ms peak flux, measured from T0+10.976 s, of 1.07(-0.15,+0.15)x10-5 erg/cm2/s (both in the 20 keV - 10 MeV energy range). The time-averaged spectrum (measured from T0 to T0+13.056 s) is best fit in the 20 keV - 1.5 MeV range by a power law with exponential cutoff model: dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep), alpha = -0.65(-0.10,+0.11), and Ep = 352(-28,+34) keV (chi2 = 51.9/60 dof). The spectrum near the maximum count rate (measured from T0+8.448 to T0+13.056 s) is best fit in the 20 keV - 1.5 MeV range by a power law with exponential cutoff model: dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep), alpha = -0.43(-0.10,+0.11), and Ep = 366(-24,+28) keV (chi2 = 58.6/60 dof). All the quoted errors are at the 90% confidence level. All the quoted values are preliminary. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15651 SUBJECT: GRB 131229A: Fermi GBM detection DATE: 14/01/02 20:50:44 GMT FROM: Narayana Bhat at U Alabama/Huntsville/GBM A. von Kienlin (MPE) and P. N. Bhat (UAH) report on behalf of the Fermi GBM Team: "At 06:39:24.48 UT on 29 December 2013, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 131229A (trigger 409991967 / 20131229277), which was also detected by the Swift/BAT (Page et al. 2013, GCN 15627 and Konus-Wind Golenetskii et al. 2013, GCN 15639). The GBM on-ground location is consistent with the Swift/XRT position (Evans et al. 2013, GCN 15631) . The angle from the Fermi LAT boresight is 84 degrees. The GBM light curve consists of multiple peaks with a duration (T90) of about 13 s (50-300 keV). The time-averaged spectrum from T0+0.002 s to T0+16.096 s is adequately fit by a power law function with an exponential high-energy cutoff. The power law index is -0.71 +/- 0.02 and the cutoff energy, parameterized as Epeak, is 382.0 +/- 11.6 keV. The event fluence (10-1000 keV) in this time interval is (2.64 +/- 0.05)E-05 erg/cm^2. The 1-sec peak photon flux measured starting from T0+13.216 s in the 10-1000 keV band is 24.0+/-0.4 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: 15668 SUBJECT: GRB 131229A: Suzaku WAM observation of the prompt emission DATE: 14/01/03 16:01:44 GMT FROM: Tetsuya Yasuda at Saitama U T. Yasuda, M. Tashiro, Y. Terada, S. Koyama, S. Takeda, Y. Ishida, H. Ueno, S. Sugimoto, T. Nagayoshi (Saitama U.), M. Yamauchi, N. Ohmori, M. Akiyama, R. Kinoshita (Univ. of Miyazaki), M. Ohno, K. Takaki, T. Kawano, R. Nakamura, S. Furui, Y. Fukazawa (Hiroshima U.), K. Yamaoka (Nagoya U.), 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 131229A (Swift/BAT trigger #582374; M. J. Page et al., GCN 15627) triggered the Suzaku Wide-band All-sky Monitor (WAM) which covers an energy range of 50 keV - 5 MeV at 06:39:29.971 UT (=T0). The observed light curve shows a multi-peaked structure starting at T0-6 s, ending at T0+13 s with a duration (T90) of about 12 s. The fluence in 100 - 1000 keV was 2.35 (+0.28/-0.30) x10^-5 erg/cm^2. The 1-s peak flux measured from T0+9 s was 13.7 (+0.8/-0.8) photons/cm^2/s in the same energy range. Preliminary result shows that the time-averaged spectrum from T0-6 s to T0+13 s is well fitted by a power-law with exponential cutoff model: dN/dE ~ E^{-alpha} * exp(-(2-alpha)*E/Epeak) with alpha 1.05 (+0.67/-0.80), and Epeak 405 (+78/-156) keV (chi^2/d.o.f. = 8.2/10). All the quoted errors are at statistical 90% confidence level. The light curves for this burst are available at: http://www.astro.isas.jaxa.jp/suzaku/HXD-WAM/WAM-GRB/grb/trig/grb_table.html