//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 12587 SUBJECT: GRB 111123A: Swift detection of a burst DATE: 11/11/23 18:33:53 GMT FROM: Scott Barthelmy at NASA/GSFC M. Stamatikos (OSU/NASA/GSFC), S. D. Barthelmy (GSFC), A. P. Beardmore (U Leicester), M. M. Chester (PSU), V. D'Elia (ASDC), N. Gehrels (NASA/GSFC), S. T. Holland (CRESST/USRA/GSFC), J. A. Kennea (PSU), A. Y. Lien (NASA/GSFC/ORAU), F. E. Marshall (NASA/GSFC), A. Melandri (INAF-OAB), P. T. O'Brien (U Leicester), D. M. Palmer (LANL), P. Romano (INAF-IASFPA), T. Sakamoto (NASA/UMBC), C. J. Saxton (UCL-MSSL), B. Sbarufatti (INAF-OAB/PSU), M. H. Siegel (PSU), R. L. C. Starling (U Leicester), G. Stratta (ASDC), G. Tagliaferri (INAF-OAB), E. Troja (NASA/GSFC/ORAU), T. N. Ukwatta (MSU) and B.-B. Zhang (PSU) report on behalf of the Swift Team: At 18:13:21 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 111123A (trigger=508319). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 154.851, -20.642 which is RA(J2000) = 10h 19m 24s Dec(J2000) = -20d 38' 28" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve shows a few overlapping peaks from T-10 to T+30 sec and then a strong peak from T+60 to T+160 sec, with a total duration of about 170 sec. The peak count rate was ~1400 counts/sec (15-350 keV), at ~3 sec after the trigger. The XRT began observing the field at 18:15:00.5 UT, 99.4 seconds after the BAT trigger. Using promptly downlinked data we find a bright, uncatalogued X-ray source with an enhanced position: RA, Dec 154.8464, -20.6453 which is equivalent to: RA(J2000) = 10h 19m 23.14s Dec(J2000) = -20d 38' 43.1" with an uncertainty of 3.3 arcseconds (radius, 90% containment). This location is 20 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. The XRT light curve shows correlated activity with BAT, rising to peak followed by fading. A power-law fit to a spectrum formed from promptly downlinked event data gives a column density consistent with the Galactic value of 5.78 x 10^20 cm^-2 (Kalberla et al. 2005). The initial flux in the 2.5 s image was 8.48e-09 erg cm^-2 s^-1 (0.2-10 keV). UVOT took a finding chart exposure of 150 seconds with the White filter starting 109 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. 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 0.05. Burst Advocate for this burst is M. Stamatikos (Michael.Stamatikos-1 AT 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: 12589 SUBJECT: GRB 111123A: GMG optical observation DATE: 11/11/24 02:23:25 GMT FROM: Dong Xu at Weizmann Inst D. Xu (WIS), X.-H. Zhao, J.-R. Mao, J.-M. Bai (YNAO) report: We observed the field of GRB 111123A (Stamatikos et al., GCN 12587) with the 2.4m Gao-Mei-Gu (GMG) telescope equipped with YFOSC, and obtained 3x600s R-band and 3x600s I-band images, starting at 21:00:56 UT on Nov. 23rd (i.e., 2.793 hrs after the burst). Within the XRT SPER error circle (http://www.swift.ac.uk/sper/), no optical source was detected in the stacked I-band image, and a weak and compact source was found in the stacked R-band image at coordinates RA(J2000) = 10:19:23.10 Dec(J2000) = -20:38:41.72 with an uncertainty of ~1" in each coordinate. We caution that the above source may be ascribed to background fluctuation. In this sense, we derive R>~23.7 mag, calibrated with the #0693-0243590 star (R1=17.95 and R2=17.60) in the USNO B1 catalog. Deeper and NIR observations are encouraged. We are grateful to Chuan-Jun Wang, De-Qing Wang, and Yan-Dong Lang for performing these observations. [GCN OPS NOTE(24nov11): Per author's request, Mao was added to the author list.] //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 12590 SUBJECT: GRB 111123A: Enhanced Swift-XRT position DATE: 11/11/24 05:02:34 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 2720 s of XRT Photon Counting mode data and 6 UVOT images for GRB 111123A, 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 = 154.84638, -20.64469 which is equivalent to: RA (J2000): 10h 19m 23.13s Dec (J2000): -20d 38' 40.9" 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: 12591 SUBJECT: GRB 111123A: MITSuME Okayama Optical upper limits DATE: 11/11/24 05:49:35 GMT FROM: Daisuke Kuroda at OAO/NAOJ D. Kuroda, K. Yanagisawa, Y. Shimizu, H. Toda (OAO, NAOJ), S. Nagayama (NAOJ), M. Yoshida (Hiroshima), K. Ohta (Kyoto) and N. Kawai(Tokyo Tech) report on behalf of the MITSuME collaboration: We observed the field of GRB 111123A (Stamatikos et al., GCNC 12587) with the optical three color (g', Rc and Ic) CCD camera attached to the MITSuME 50cm telescope of Okayama Astrophysical Observatory. The observation started on 2011-11-23 18:30:27 UT (~17 min after the burst). We did not find any new point source within the enhanced XRT circle (Goad, et al., GCNC 12590) in all the three bands. Three sigma upper limits of the OT are listed below. We used GSC2.3 catalog for flux calibration. T0+[day] MID-UT T-EXP[sec] g' Rc Ic ------------------------------------------------------ 0.01541 18:35:32 540.0 >18.9 >18.9 >18.3 0.04573 19:19:12 5820.0 >20.4 >20.2 >19.6 ------------------------------------------------------ T0+ : Elapsed time after the burst [day] T-EXP: Total Exposure time [sec] //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 12592 SUBJECT: GRB 111123A: Swift-XRT refined Analysis DATE: 11/11/24 09:34:05 GMT FROM: Phil Evans at U of Leicester G. Stratta (ASDC), D.N. Burrows (PSU), J.A. Kennea (PSU), M.C. Stroh (PSU), O.M. Littlejohns (U. Leicester), J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), P. D'Avanzo (INAF-OAB), V. D'Elia (ASDC) and M. Stamatikos report on behalf of the Swift-XRT team: We have analysed 11 ks of XRT data for GRB 111123A (Stamatikos et al. GCN Circ. 12587), from 88 s to 35.6 ks after the BAT trigger. The data comprise 656 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 Goad et al. (GCN. Circ 12590). The late-time light curve (from T0+4.2 ks) can be modelled with a power-law decay with a decay index of alpha=0.86 (+/-0.10). A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 1.715 (+/-0.026). The best-fitting absorption column is 2.62 (+0.10, -0.09) x 10^21 cm^-2, in excess of the Galactic value of 5.8 x 10^20 cm^-2 (Kalberla et al. 2005). The PC mode spectrum has a photon index of 2.43 (+0.19, -0.18) and a best-fitting absorption column of 2.0 (+/-0.4) x 10^21 cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.1 x 10^-11 (5.8 x 10^-11) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Total column: 2.0 (+/-0.4) x 10^21 cm^-2 Galactic foreground: 5.8 x 10^20 cm^-2 Excess significance: 7.4 sigma Photon index: 2.43 (+0.19, -0.18) The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00508319. This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 12593 SUBJECT: GRB 111123A: TNG NIR detection of the afterglow candidate DATE: 11/11/24 12:33:57 GMT FROM: Paolo D'Avanzo at INAF-OAB D. Fugazza (INAF-OAB), V. D'Elia (INAF-OAR), P. D'Avanzo, A. Melandri (INAF-OAB) and E. Palazzi (INAF-IASFBo) on behalf of a larger collaboration report: We observed the field of GRB 111123A (Stamatikos et al. GCN 12587) with the 3.6m TNG equipped with the NICS near-infrared camera. A sequence of JHK band images were acquired starting on Nov 24.238 UT (i.e. ~11.5 hours after the burst event). An object is detected in a stacked 20 min exposure image inside the enhaced XRT error circle (Goad et al. GCN 12590) at the following coordinates (J2000): R.A. = 10:19:23.14 Dec. = -20:38:41.0 with an uncertainty of ~ 0.3", consistent with the position of the object reported by Xu et al. (GCN 12589). The source has a magnitude K=19.4 +/- 0.3 (calibrated against the 2MASS catalogue). The source is not detected in the shorter exposures (10 min) J and H-band images down to the following 3sigma upper limits: J>19.7, H>20.5. At the present stage, it is not possible to say anything about source variability. We thank the TNG staff for their support, in particular Luca Di Fabrizio. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 12594 SUBJECT: GRB 111123A: correction to GCN 12593 DATE: 11/11/24 13:58:56 GMT FROM: Paolo D'Avanzo at INAF-OAB P. D'Avanzo (INAF-OAB) on behalf of a larger collaboration report: The TNG NIR 3sigma upper limits of GRB 111123A reported in Fugazza et al. (GCN 12593) has been written in the wrong order. The correct values are: J>20.5 H>19.7 (calibrated against the 2MASS catalogue). We confirm the K-band detection. We apologize for the confusion that our previous report may have caused. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 12595 SUBJECT: GRB 111123A, GROND observations DATE: 11/11/24 16:04:07 GMT FROM: Ana Nicuesa at TLS Tautenburg A. Rossi, A. Nicuesa Guelbenzu, S. Klose (all Tautenburg), P. Afonso (American River College), and J. Greiner (MPE) report on behalf of the GROND team: We observed the field of GRB 111123A (Stamatikos, GCN 12587) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, PASP 120, 405) mounted at the 2.2-m MPI/ESO telescope on La Silla. Observations started at 6:30 UT on November 24, about 12 hr after the burst, and continued for about 1.5 hr. They were performed at an average seeing of 1 arcsec and an average airmass of 1.5. We do not detect the source discovered by Xu et al. (GCN 12589; see also Fugazza et al. GCN 12593). At a mean time of November 24, 7:10 UT, we measure the following preliminary upper limits (AB magnitudes): g' > 24.5, r' > 24.6, i' > 23.7, J > 21.2, H > 20.9, K > 19.9. The data are calibrated against GROND zeropoints and 2MASS field stars. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 12596 SUBJECT: GRB 111123A - NOT optical observations DATE: 11/11/24 17:38:19 GMT FROM: Annalisa De Cia at U of Iceland A. De Cia (U. of Iceland), D. Xu (WIS), N.R. Tanvir (U. of Leicester), G. Leloudas, D. Malesani (DARK), G. Maciejewski (U. Nicolaus Copernicus), A. de Ugarte Postigo (IAA/CSIC), J.P.U. Fynbo (DARK) and P. Jakobsson (U. of Iceland) report: We observed the field of GRB 111123A (Stamatikos et al., GCN 12587, Fugazza et al. 12593) with the NOT equipped with ALFOSC at the end of the night in La Palma, when the humidity dropped below the observability threshold. Observations were carried out in the R filter for 30 minutes, starting at 5:59 UT, with a mean time of 12.02 hours after the GRB trigger. No significant source was detected at the position of the candidate optical afterglow (Xu et al., GCN 12589) down to R>~24.4 mag, calibrated against USNO-B1stars. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 12597 SUBJECT: GRB 111123A: Swift/UVOT Upper Limits DATE: 11/11/24 20:37:04 GMT FROM: Stephen Holland at USRA/NASA/GSFC/SSC S. T. Holland (CRESST/USRA/GSFC) and M. Stamatikos (OSU/NASA/GSFC) report on behalf of the Swift/UVOT team: The Swift/UVOT observed the field of GRB 111123A starting 90 s after the BAT trigger (Stamatikos et al., 2011, GCNC 12587). Settled observations started at 110 s. We do not detect an optical afterglow at the location of the optical and near-infrared afterglow (Xu et al., 2011, GCNC 12589; Fugazza et al., 2011, GCNC 12593) in any of the UVOT filters. Preliminary 3-sigma upper limits for detecting a source in the finding charts and in the co-added images, are Filter TSTART TSTOP EXPOSURE Mag --------------------------------------------------- white (FC) 110 260 147 >21.2 u (FC) 268 518 246 >20.3 white (FC) 871 934 62 >20.1 --------------------------------------------------- v 598 5999 430 >20.2 b 524 6711 325 >20.7 u 268 6614 678 >20.8 uvw1 647 6409 432 >20.6 uvm2 622 6204 432 >20.6 uvw2 573 5795 432 >20.9 white 110 5589 445 >21.7 --------------------------------------------------- The quoted magnitudes and upper limits have not been corrected for the Galactic extinction along the line of sight to this burst of E_{B-V} = 0.05 mag (Schlegel et al. 1998, ApJS, 500, 525). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 12598 SUBJECT: GRB 111123A, Swift-BAT refined analysis DATE: 11/11/26 00:24:19 GMT FROM: Takanori Sakamoto at NASA/GSFC H. A. Krimm (GSFC/USRA), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (GSFC/UMBC), 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-240 to T+962 sec from the recent telemetry downlink, we report further analysis of BAT GRB 111123A (trigger #508319) (Stamatikos, et al., GCN Circ. 12587). The BAT ground-calculated position is RA, Dec = 154.845, -20.639 deg which is RA(J2000) = 10h 19m 22.9s Dec(J2000) = -20d 38' 19.9" with an uncertainty of 1.1 arcmin, (radius, sys+stat, 90% containment). The partial coding was 81%. The mask-weighted light curve shows two episodes. The first episode is starting at T-10 sec, and peaking at T+10 sec with possible two or three overlapping pulses. The second episode shows a gradual increases after the end of the initial episode, peaks at T+150 sec, and ends at T+170 sec. The low level emission continues up to T+~300 sec. T90 (15-350 keV) is 290.0 +- 88.1 sec (estimated error including systematics). The time-averaged spectrum from T-8.7 to T+481.3 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.68 +- 0.07. The fluence in the 15-150 keV band is 7.3 +- 0.3 x 10^-06 erg/cm2. The 1-sec peak photon flux measured from T+146.30 sec in the 15-150 keV band is 0.9 +- 0.1 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/508319/BA/ //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 12613 SUBJECT: GRB 111123A: optical upper limit in CrAO DATE: 11/12/04 16:11:41 GMT FROM: Alexei Pozanenko at IKI, Moscow We observed the field of GRB 111123A (Stamatikos et al. GCN 12587) with Shajn telescope of CrAO observatory on Nov. 25 between (UT) 02:48 and 03:44 under a mean seeing of 2.0 arsces and large airmass. We took several frames with exposure of 60 s in I-band. Within enhanced Swift-XRT position (Goad et al. GCN 12590) we do not detected the optical counterpart (Xu et al., GCN 12589; Fugazza et al., GCN 12593). A photometry is based on the USNO B1.0 star 0693-0243552 (10 19 20.57, -20 39 18.7, J2000) assuming I=16.85. T_start UT T0+ Filter, Exposure, OT, uplim (3 sigma) (mid, d) (s) 02:48:33 1.89584 I 49x60 n/d 22.2 //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 12615 SUBJECT: GRB 111123A: optical upper limit in CrAO: correction to the GCN circ. 12613 DATE: 11/12/04 16:57:12 GMT FROM: Alexei Pozanenko at IKI, Moscow The text of the GCN circular #12613 should be corrected as following. I apologize for possible inconvenience. V. Rumyantsev, (CrAO), A. Pozanenko (IKI) report on behalf of larger GRB follow-up collaboration: We observed the field of GRB 111123A (Stamatikos et al. GCN 12587) with Shajn telescope of CrAO observatory on Nov. 25 between (UT) 02:48 and 03:44 under a mean seeing of 2.0 arsces and large airmass. We took several frames with exposure of 60 s in I-band. Within enhanced Swift-XRT position (Goad et al. GCN 12590) we do not detected the optical counterpart (Xu et al., GCN 12589; Fugazza et al., GCN 12593). A photometry is based on the USNO B1.0 star 0693-0243552 (10 19 20.57, -20 39 18.7, J2000) assuming I=16.85. T_start UT T0+ Filter, Exposure, OT, uplim (3 sigma) (mid, d) (s) 02:48:33 1.89584 I 49x60 n/d 22.2 //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 14273 SUBJECT: GRB 111123A: Keck-I host detection and VLT/X-shooter redshift DATE: 13/03/08 10:59:57 GMT FROM: Dong Xu at DARK/NBI D. Xu, D. Malesani, T. Kruehler, J. P. U. Fynbo (DARK/NBI), D. A. Perley (Caltech), P. Goldoni (APC/Univ. Paris 7 and SAp/CEA), L. Kaper (U. Amsterdam), A. de Ugarte Postigo (IAA-CSIC and DARK/NBI), N. R. Tanvir (U. Leicester) report on behalf of the X-shooter GTO GRB collaboration: We observed the field of GRB 111123A (Stamatikos et al., GCN 12587) using the Keck-I telescope equipped with the LRIS instrument. Observations were carried out on 2013 February 10 (~444 days after the burst), simultaneously in the g and I bands, for a total exposure time of 750 and 720 s, respectively. An extended source with g=25.83 (AB) and I = 23.55 (Vega) is detected at the position of the optical and NIR afterglow (Xu et al., GCN 12589; Fugazza et al., GCN 12593), where the positional error radius of the optical afterglow has been reduced from ~1.0" to ~0.3" through a refined analysis. We thus consider the source to be the host galaxy of GRB 111123A. A spectrum of this source was taken on 2013 March 07 with the ESO VLT equipped with the X-shooter spectrograph, featuring NIR/VIS/UVB three arms and covering the wavelength range 3000-25000 AA. The exposure time was 4x600 s. In the NIR arm, we detect four emission lines, interpreted as [O III] (5007), [NeIII] (3869), [O II] (3727), and Hbeta (a marginal detection), all at a common redshift z = 3.1516. In the UVB arm, the host continuum is detected down to ~5100 AA, thus corresponds to the onset of the Lyman alpha forest at the proposed redshift. We acknowledge excellent support from the observing staff at Mauna Kea and Paranal, in particular Emanuela Pompei, Claudio Melo, and Andres Pino.