//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 7121 SUBJECT: GRB 071122: Swift detection of a burst DATE: 07/11/22 01:45:10 GMT FROM: Scott Barthelmy at NASA/GSFC M. Stamatikos (NASA/ORAU), S. D. Barthelmy (GSFC), A. P. Beardmore (U Leicester), P. J. Brown (PSU), M. M. Chester (PSU), J. R. Cummings (NASA/UMBC), P. A. Evans (U Leicester), N. Gehrels (NASA/GSFC), S. T. Holland (CRESST/USRA/GSFC), S. Immler (GSFC/UMCP), J. A. Kennea (PSU), C. B. Markwardt (CRESST/GSFC/UMD), F. E. Marshall (NASA/GSFC), C. Pagani (PSU), K. L. Page (U Leicester), D. M. Palmer (LANL) and T. N. Ukwatta (GSFC/GWU) report on behalf of the Swift Team: At 01:23:25 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 071122 (trigger=297114). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 276.581, +47.063 which is RA(J2000) = 18h 26m 20s Dec(J2000) = +47d 03' 47" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). As is typical with image triggers, there is nothing obvious in the TDRSS lightcurve. In these cases, the bursts often have long duration. The XRT began observing the field at 01:25:45 UT, 140 seconds after the BAT trigger. Using prompt downlinked data, we find an uncatalogued fading X-ray source located at RA, Dec 276.6056, 47.0770 which is RA(J2000) = 18 26 25.34 Dec(J2000) = +47 04 37.2 with an uncertainty of 4.1 arcsec (radius, 90% containment). This location is 79 arcseconds from the BAT on-board position, within the BAT error circle. The initial flux in the 2.5s image was 6.9e-10 erg/cm2/s (0.2-10 keV). UVOT took a finding chart exposure of 100 seconds with the White (160-650 nm) filter starting 145 seconds after the BAT trigger. No 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 3-sigma upper limit is 19.4 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 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: 7122 SUBJECT: GRB 071122: ROTSE-III Optical Limits DATE: 07/11/22 02:00:31 GMT FROM: Eli Rykoff at UCSB E.S. Rykoff (UCSB), W. Rujopakarn (Steward), B. E. Schaefer (Louisiana State), T.A. McKay (U Mich), H. Swan (U Mich), report on behalf of the ROTSE collaboration: ROTSE-IIIb, located at McDonald Observatory, Texas, responded to GRB 071122 (Swift trigger 297114; Stamatikos et al., GCN 7121), producing images beginning 8.5 s after the GCN notice time. An automated response took the first image at 01:24:51.5 UT, 85.9 s after the burst, under fair conditions. These observations were affected by proximity to the full moon. We took 10 5-sec, and 30 20-sec exposures. These unfiltered images are calibrated relative to USNO A2.0 (R). Imaging is on going. Comparison to the DSS (second epoch) reveals no new sources within the 3-sigma Swift/BAT error circle or the XRT error circle, for both single images and coadding into sets of 10. Individual images have limiting magnitudes ranging from 15.7-16.8; we set the following specific limits. start UT end UT t_exp(s) mlim t_start-tGRB(s) Coadd? -------------------------------------------------------------------- 01:24:51.5 01:24:56.5 5 15.8 85.9 N 01:24:51.4 01:25:58.5 67 17.3 85.8 Y 01:26:12.0 01:30:54.8 282 17.8 166.4 Y //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 7123 SUBJECT: GRB 071122: P60 Optical Afterglow Candidate DATE: 07/11/22 03:29:24 GMT FROM: S. Bradley Cenko at Caltech S. B. Cenko (Caltech), D. B. Fox (Penn State), and Eran Ofek (Caltech) report on behalf of a larger collaboration: We have imaged the field of GRB071122 (Stamatikos et al., GCN 7121) with the automated Palomar 60-inch telescope. Observations began at approximately 01:41 UT 22 November (~ 18 min after the burst). Just outside the XRT error circle, we detect a stationary, faint point source not present in the Digital Sky Survey images of the field at coordinates (J2000.0): RA: 18:26:25.34 Dec: +47:04:37.2 Using nearby USNO-B stars for photometric calibration, the object appears to increase in brightness from I ~ 20.2 (01:54 UT) to I ~ 19.8 (02:33 UT). We therefore consider it likely this is the optical afterglow of GRB071122. Further observations to confirm the variable nature of this source are encouraged. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 7124 SUBJECT: GRB071122: Gemini Absorption redshift DATE: 07/11/22 06:36:13 GMT FROM: Antonino Cucchiara at PSU A. Cucchiara, D. B. Fox (Penn State) and S. B. Cenko (Caltech) on behalf of a large collaboration: Starting on 2007 November 22.19 UT we used the GMOS spectrograph on the Gemini North telescope to obtain two spectra of 900 each of the optical afterglow of GRB071122 (GCN 7121, 7123). The spectrum covers the wavelength range 5900-10000A. We clearly detect absorption features corresponding to MgII doublet, MgI, Ca H&K at a redshift of z=1.14, which we identify as the redshift of the grb. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 7125 SUBJECT: GRB 071122: Corrected P60 Coordinates DATE: 07/11/22 08:18:59 GMT FROM: S. Bradley Cenko at Caltech S. B. Cenko (Caltech) reports: In our previous circular (GCN 7123), I incorrectly transcribed the coordinates of the proposed afterglow candidate of GRB071122. The correct coordinates are (J2000.0): RA: 18:26:25.23 Dec: +47:04:31.3 I would like to thank Phil Evans for pointing out this typo and apologize for any inconvenience this may have caused. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 7126 SUBJECT: GRB 071122 Swift-XRT refined analysis DATE: 07/11/22 10:23:32 GMT FROM: Phil Evans at U of Leicester P.A. Evans, K.L. Page, R.L.C. Starling (U. Leicester) and M. Stamatikos (NASA/ORAU) report on behalf of the Swift-XRT team: We have analysed 1.4 ks of Swift XRT data for GRB 071122 (Stamatikos et al. GCN Circ 7121), comprising 125 s in Windowed Timing (WT) mode and 1.3 ks in Photon Counting (PC) mode. The observations started 146 s after the BAT trigger. Using 778 s of overlapping XRT Photon Counting mode and UVOT V-band data, 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 = 276.60547, 47.07504 which is equivalent to: RA (J2000): 18 26 25.31 Dec (J2000): +47 04 30.1 with an uncertainty of 1.7 arcsec (radius, 90% confidence). This position is 1.5 arcsec from the optical afterglow reported by Cenko (GCN Circ 7125), 74 arcsec from the initial BAT position, within the BAT error circle, and 7.1 arcsec from the initial XRT position. The XRT light curve follows a power-law decay with alpha=2.52 (+0.10/-0.09). There is also a small flare at approximately T0+400 s. The WT mode spectrum can be fitted with an absorbed power-law, with the absorption column fixed at the Galactic value of 4.75e20 cm^-2. Adding a redshifted absorber at z=1.14 (Cucchiara et al. GCN Circ 7124) improved the fit marginally, with chi-squared decreasing from 36.14 for 39 degrees of freedom, to 32.83 for 38 degrees of freedom. An f-test indicates that the probability of this being a chance improvement is ~5%. The redshifted absorber has a column density of 9.9e20 (+10.0e20/-9.0e20) cm^-2, and a power-law index, gamma of 2.00 (+0.14/-0.13). The observed (unabsorbed) 0.3-10 keV flux is 2.52e-10 (3.04e-10) erg cm^-2 s^-1. The predicted count-rate at T+24 hours is 1.69e-6 s^-1, which corresponds to an observed (unabsorbed) 0.3-10 keV flux of 6.11e-17 (7.37e-17) erg cm^-2 s^-1. Due to the proximity of this GRB to the sun, no further observations are planned. This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 7127 SUBJECT: GRB 071122 Swift XRT position update sent in error. DATE: 07/11/22 14:23:35 GMT FROM: Phil Evans at U of Leicester P.A. Evans reports, The GCN Swift XRT position update notice sent at 12:44:49 UT was sent in error during the testing of some software modifications. This message should be disregarded. The best XRT position is still that of GCN Circular 7126. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 7128 SUBJECT: GRB 071122, Swift-BAT refined analysis DATE: 07/11/22 14:28:37 GMT FROM: Takanori Sakamoto at NASA/GSFC T. Sakamoto (GSFC/UMBC), S. D. Barthelmy (GSFC), J. Cummings (GSFC/UMBC), E. Fenimore (LANL), N. Gehrels (GSFC), H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD), D. Palmer (LANL), G. Sato (GSFC/ISAS), M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC), T. Ukwatta (GWU) (i.e. the Swift-BAT team): Using the data set from T-239 to T+723 sec from recent telemetry downlinks, we report further analysis of BAT GRB 071122 (trigger #297114) (Stamatikos, et al., GCN Circ. 7121). The BAT ground-calculated position is RA, Dec = 276.576, 47.102 deg which is RA(J2000) = 18h 26m 18.2s Dec(J2000) = 47d 6' 6" with an uncertainty of 2.3 arcmin, (radius, sys+stat, 90% containment). The partial coding was 69%. The mask-weighted lightcurve shows a single, rougly symmetrical peak starting at ~T-30 sec, peaking at ~T+5 sec, and ending at ~T+60 sec. T90 (15-350 keV) is 68.7 +- 14.4 sec (estimated error including systematics). The time-averaged spectrum from T-29.4 to T+47.3 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.77 +- 0.31. The fluence in the 15-150 keV band is 5.8 +- 1.1 x 10^-07 erg/cm2. The 1-sec peak photon flux measured from T+3.00 sec in the 15-150 keV band is 0.4 +- 0.2 ph/cm2/sec. All the quoted errors are at the 90% confidence level. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 7129 SUBJECT: GRB 071122: MASTER optical observation DATE: 07/11/22 18:55:13 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, V.Kornilov, D.Kuvshinov, N.Tyurina, A.Belinski, E.Gorbovskoy, A.Krylov, N.Shatskiy, A.Sankovich, G.Borisov, V.Vladimirov, P.Gritsyk, V.Vibornov, A.Kuznetsov Sternberg Astronomical Institute, Moscow Union 'Optic' A. Tlatov, I.Golubov Kislovodsk Solar Station of the Pulkovo observatory Krushinski V., I.Zalozhnih Ural State University MASTER robotic system (http://observ.pereplet.ru) responded to GRB 071122.1 (GRB_TIME is 2007-11-22 01:23:25.62, M. Stamatikos et al., GCN Circ N 7121). The first image was at 2007-11-22 01:25:57 UT, 69 s after the GCN notice time and 151 s after the GRB time. These observations were affected by proximity to the full moon. The unfiltered image is calibrated relative to USNO A2.0 (0.8 R + 0.2 B). The robot not find OT-candidate in error box brighter then 15.6 (s/n=10). Individual images have limiting magnitudes about 16. We set the following specific limits for S. B. Cenko (GCN Circ 7125) OT position. start UT t_start-t_GRB mean t_GRB t_exp(s) mlim Coadd? -------------------------------------------------------------------- 01:25:57.6 151 s 166 s 30 16.0 N 01:25:57.6 151 s 266 s 5x30 16.8 Y 01:30:06.6 6 min 42 s 14 min 53 s 20x30 17.7 Y 01:34:15.9 11 min 00 s 15 min 02 s 10x30 17.2 Y 01:42:40.3 19 min 15 s 23 min 15 s 10x30 17.2 Y 01:50:59.5 27 min 35 s 31 min 38 s 10x30 17.2 Y The reduction is continuing. The delay of the given telegram is connected with participation and successful end of national Russia football teem on a selection cycle EURO' 08. Our collective is especially grateful to national Croatia-teem for the help during the difficult moment! The reduction is continuing. This message can be cited. Mailto: lipunov@sai.msu.ru //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 7131 SUBJECT: GRB071122: Swift/UVOT Observations DATE: 07/11/23 18:27:22 GMT FROM: Peter Brown at PSU P. J. Brown, M. M. Chester (PSU), R. L. C. Starling (U. Leicester), and M. Stamatikos (NASA/ORAU) report on behalf of the Swift/UVOT team: Swift/UVOT observed the field of GRB 071122 (trigger #297114) starting 145 s after the BAT trigger (Stamatikos et al., GCN Circ. 7121). A faint source is detected in the first white exposure at a position of 18h 26m 25.38s, Dec = +47d 4m 30.8s, consistent with the optical afterglow found by Cenko (GCN Circ. 7125) and the revised XRT position (Evans et al., GCN Circ. 7126). The afterglow is detected at a level of 4 sigma and has a magnitude of white=20.8 +- 0.3 (one sigma error), with an exposure midpoint time of 196 s after the trigger. It is not detected in subsequent exposures in white or the other 6 filters. The detection and 3-sigma upper limits in the coadded frames are summarized in the following table: Filter T_start(s) T_stop(s) Exp(s) Mag/3-sigma UL white 145 245 100 20.8 +- 0.3 white 748 1483 119 >21.3 v 252 1517 823 >21.2 b 733 1469 30 >19.6 u 708 1444 40 >19.4 uvw1 684 703 20 >19.2 uvm2 658 1395 59 >18.7 uvw2 763 1508 40 >18.8 The values quoted above are not corrected for the expected Galactic extinction corresponding to a reddening of E(B-V) = 0.048 mag towards the direction of the burst (Schlegel et al. 1998). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 7132 SUBJECT: VLA radio detection of GRB 071122 DATE: 07/11/25 20:32:23 GMT FROM: Poonam Chandra at U Virginia/NRAO P. Chandra (UVA/NRAO) and D. A. Frail (NRAO) report on behalf of the Caltech-NRAO-Carnegie GRB Collaboration: "We observed the Swift burst GRB 071122 (GCN 7121) using the VLA at a frequency of 8.46 GHz. The observations were taken at 22.46 UT on 2007, November 24. We detect a radio emission at the P60 afterglow position (GCN 7123, 7125). The flux density at the P60 position is 255 +/- 45 uJy. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc."