This file contains both GRBs: 060111A AND 060111B //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4479 SUBJECT: GRB 060111: Swift detection of a burst DATE: 06/01/11 05:05:37 GMT FROM: Scott Barthelmy at NASA/GSFC S. Zane (MSSL-UCL), S. Barthelmy (GSFC), A. Beardmore (U Leicester), A. J. Blustin (UCL-MSSL), D. Burrows (PSU), J. Cummings (GSFC/NRC), N. Gehrels (GSFC), M. Goad (U Leicester), J. Kennea (PSU), C. Markwardt (GSFC/UMD), F. Marshall (GSFC), D. Palmer (LANL) on behalf of the Swift team: At 04:23:06 UT, Swift-BAT triggered and located GRB 060111 (trigger=176818). The spacecraft slewed immediately. The BAT on-board calculated location is RA,Dec 276.212d,+37.602d {18h 24m 51s,+37d 36' 08"} (J2000), with an uncertainty of 3 arcmin (radius, 90% containment, stat+sys). The BAT light curve shows a single peak structure with a total duration of ~20 sec. The peak count rate was ~3000 counts/sec (15-350 keV), at ~5 sec after the trigger. The XRT began observing the field at 04:24:12 UT (66 sec after the burst). The instrument found a bright, variable, uncataloged X-ray source located at: RA(J2000) = 18h 24m 48.9s Dec(J2000) = +37d 36' 21" This location is 27.4 arcseconds from the BAT position. The estimated uncertainty is 8 arcseconds (90% confidence radius), including about 5 arcseconds systematic error due to an XRT boresight offset not currently corrected on-board. The initial flux was 8E-10 ergs/cm2/s (0.2-10 keV). UVOT took a finding chart exposure of 200 seconds with the V filter starting 72 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 typical 3-sigma upper limit has been about 18th 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 18.0 mag. No correction has been made for the expected visual extinction of about 0.1 magnitudes. We are currently in the portion of the orbits where the spacecraft does not pass over the Malindi downlink station. Therefore, it will be at least 7 hours before we have access to the full data set for the refined analyses. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4480 SUBJECT: GRB 060111: ROTSE-III Optical Limits DATE: 06/01/11 05:12:43 GMT FROM: Fang Yuan at ROTSE F. Yuan (U Mich), W. Rujopakarn (U Mich), E.S. Rykoff (U Mich), S.A. Yost (U Mich), report on behalf of the ROTSE collaboration: ROTSE-IIId, located at the Turkish National Observatory at Bakirlitepe, Turkey, responded to GRB 060111 (Swift trigger 176818), producing images beginning 5 s after the GCN notice time. An automated response took the first image at 04:23:23.2 UT, 17.1 s after the burst, under twilight conditions. We took 10 5-sec eposures before the individual images were saturated due to twilight. These unfiltered images are calibrated relative to USNO A2.0 (R). Comparison to the DSS (second epoch) reveals no new sources within the 3-sigma error circle and particularly at the XRT position, for both single images and coadding into sets of 10. Individual images have limiting magnitudes ranging from 13.4-13.8; we set the following specific limits. start UT end UT t_exp(s) mlim t_start-tGRB(s) Coadd? -------------------------------------------------------------------- 04:23:23.2 04:23:28.2 5 13.4 17.1 N 04:23:23.2 04:25:31.0 127.8 14.5 17.1 Y //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4481 SUBJECT: GRB060111 : XRT refined analysis DATE: 06/01/11 13:23:02 GMT FROM: Michael Goad at U Leicester M.R. Goad, A.P. Beardmore, K. Page (U. Leicester), D. Burrows (PSU), R. Fink (GSFC), M. Ajello (MPE) report on behalf of the Swift XRT team. From analysis of 2.5 ks of Photon Counting mode data of GRB060111 (Zane et al., GCN 4479) starting in the 2nd orbit of observations, we obtain a refined XRT position of RA: 18h 24m 49.0s, Dec:+37d 36m 16.1s (J2000) with an uncertainty of 3.6 arcsec (90% containment). This includes the latest XRT boresight correction. This refined position is 25.1 arcsec from the BAT on-board position and 5 arcsec from the XRT on-board position quoted in GCN 4479. We have also analysed 400 s of XRT Windowed Timing mode observations starting 78 s after the BAT trigger. The XRT lightcurve displays 3 large flares with a peak count rate of approximately 150 ct/s occurring 280 s after the BAT trigger. The light-curve has an underlying powerlaw decay of slope -1.3. The XRT WT mode 0.3-10 keV spectrum is well represented by an absorbed powerlaw with photon index 2.35 +/-0.04 with a mean unabsorbed flux of 2.5e-9 ergs/cm2/s. We find evidence for excess NH of 2.4e21 cm^-2. The predicted 0.3-10 keV unabsorbed flux 24 hours after the BAT trigger is 1.2e-13 ergs/cm2/s //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4482 SUBJECT: GRB 060111: possible UVOT counterpart DATE: 06/01/11 13:31:24 GMT FROM: Alexander Blustin at MSSL-UCL A. J. Blustin (UCL-MSSL), S. Zane (UCL-MSSL), S. R. Rosen (UCL-MSSL) on behalf of the Swift/UVOT team Further analysis of the initial UVOT data for GRB 060111 (Zane et al., GCN 4479) reveals a potential afterglow candidate at RA,Dec (J2000) = 18:24:49.132 +37:36:14.47 within the refined XRT error circle (Goad et al., GCN 4481). The source, significant at 8 sigma in an 3 arcsec radius aperture, has a V band magnitude of 18.9 +/- 0.4 in a 200 s exposure starting at 72 s after the BAT trigger. This magnitude is uncorrected for Galactic extinction (E(B-V) ~0.1). //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4483 SUBJECT: GRB 060111: TAROT optical observation DATE: 06/01/11 15:44:08 GMT FROM: Alain Klotz at CESR-CNRS Klotz, A. (CESR-OMP), Boer M. (OHP), Atteia J.L. (LATT-OMP) report: We imaged the field of GRB 060511 detected by SWIFT (trigger 176818) with the TAROT robotic telescope (D=25cm) located at the Calern observatory, France. First image was acquired 20s after the GCN trigger (7s after the notice). The field elevation increased from 23 degrees above horizon and weather conditions were good. Moon was just rising (23 deg from the field) at the begining of observations. Due to a technical problem, there was no image between 261 and 510s after the trigger. We detected no new source comparing our individual unfiltered images with the USNO-B1 catalog within the error circle at the XRT position (Goad et al. GCNC 4481). From individual frames we give early limits: Day : 2006-01-11 UT-start UT-end (sec since GRB) Exp(s) R-mag 04:23:25.7 - 04:24.25.7 20 - 80 60 >16.2 (one frame trailed) 04:24:32.4 - 04:25.02.4 86 - 116 30 >17.0 (one frame) 04:25:08.7 - 04:25.38.7 122 - 152 30 >17.0 (one frame) 04:31:36.2 - 04:33:06.2 510 - 600 90 >17.7 (one frame) To increase the signal to noise, we co-added series frames. The source at the XRT position (Goad et al. GCNC 4481) is marginaly detected on the first co-addition: Day : 2006-01-11 UT-start UT-end (sec since GRB) R-mag 04:24:32 - 04:27.27 86 - 261 ~18.3 (sum of 5 frames of 30s) 04:31:36 - 04:40.13 510 - 1027 >18.7 (sum of 6 frames of 90s) Magnitudes were estimated with the nearby USNO-B1 stars. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4485 SUBJECT: GRB060111.2:_MASTER optical limit DATE: 06/01/11 19:15:26 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, V.Kornilov, D.Kuvshinov, N.Tyurina, A.Belinski, E.Gorbovskoy, A.Krylov, G.Borisov, A.Sankovich, G.Antipov, V.Vladimirov Sternberg Astronomical Institute, Moscow Union 'Optic' MASTER robotic system (http://observ.pereplet.ru) responded to GRB060111.2 (GRB_TIME is 2006-01-11 04:23:06.12). The first image was at 2006-01-11 04:25:16 UT, 130 s after the GRB time (a half of an hour befor sunrise). 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. Our final results on OT magnitude limit are: UT (start) Mean time After GRB time m exptime 04 25 16 04 25 31 130 s 16.0 30 sec The first JPG-image will be available at http://observ.pereplet.ru/images/GRB060111.2/1.jpg . This work is supported by RFFI 04-02-16411 grant. This message can be cited. Mailto: lipunov@sai.msu.ru This message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4486 SUBJECT: GRB 060111: Swift-BAT Refined Analysis DATE: 06/01/11 20:16:06 GMT FROM: Jay R. Cummings at NASA/GSFC/Swift G. Sato (ISAS), L. Barbier (GSFC), S. Barthelmy (GSFC), J. Cummings (GSFC/ORAU), E. Fenimore (LANL), N. Gehrels (GSFC), D. Hullinger (UMD), H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD), F. Marshall (GSFC), D. Palmer (LANL), A. Parsons (GSFC), T. Sakamoto (GSFC/ORAU), A. Smale (NASA HQ), J. Tueller (GSFC), on behalf of the Swift-BAT team: Using the data set from T-299 to T+303.0 sec from the recent telemetry downlink, we report further analysis of BAT GRB 060111 (trigger #176818) (Zane, et al., GCN 4479). The BAT ground-calculated position is (RA,Dec) = 276.195, 37.596 {18h 24m 47.3s, 37d 35' 44.1"} (deg; J2000) +- 0.8 arcmin, (radius, sys+stat, 90% containment). The partial coding was 98%. The light curve is a single peak, rise slightly faster than its decay. T90 (15-350 keV) is (13 +- 1) sec (estimated error including systematics). There is a small bump of marginal significance in the 15-50 keV band at T+280, the time of the x-ray flare observed by the XRT (GCN circ. #4481, Goad et al.). The time-averaged spectrum from T-0.7 to T+14.7 is best fit by a cut-off power law with an Epeak of (72 +14, -8) keV and a photon index of 0.8 +- 0.3. The fluence in the 15-150 keV band is (1.18 +- 0.05) x 10^-06 erg/cm2. A simple power law also gives an acceptable fit, with a photon index of 1.63 +/- 0.07 and a fluence of (1.25 +- 0.05) x 10^-06 erg/cm2. The 1-sec peak photon flux measured from T+4.3 sec in the 15-150 keV band is (1.72 +- 0.15) ph/cm2/sec. All the quoted errors are at the 90% confidence level. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4487 SUBJECT: GRB 060111B: Swift detection of a burst DATE: 06/01/11 20:53:53 GMT FROM: Scott Barthelmy at NASA/GSFC M. Perri (ASDC), S. Barthelmy (GSFC), P. Boyd (GSFC), D. Burrows (PSU), J. Cummings (GSFC/NRC), N. Gehrels (GSFC), C. Gronwall (PSU), J. Kennea (PSU), H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD), F. Marshall (GSFC), D. Palmer (LANL), T. Sakamoto (GSFC) on behalf of the Swift team: At 20:15:43 UT, Swift-BAT triggered and located GRB 060111B (trigger=176918). The spacecraft slewed immediately. The BAT on-board calculated location is RA,Dec 286.337d,+70.360d {19h 05m 21s,+70d 21' 35"} (J2000), with an uncertainty of 3 arcmin (radius, 90% containment, stat+sys). The BAT light curve shows a main peak with a total duration of at least 25 sec. There is a possible second peak at T+55 sec. The peak count rate was ~2000 counts/sec (15-350 keV), at ~2 seconds after the trigger. XRT began observing the field at 20:17:02 UT, 79 seconds after the BAT trigger. On-board centroiding found a previously uncatalogued fading X-ray source in the field of view at the following coordinates: RA(J2000) = 19 05 42.3 Dec(J2000)= 70 22 37 This location is 124 arcseconds from the BAT position. The estimated uncertainty is 8 arcseconds (90% confidence radius), including a systematic error of about 5 arcseconds due to an XRT boresight offset not currently corrected on-board. The initial flux was 1.7e-09 ergs/cm2/s (0.2-10 keV). UVOT took a finding chart exposure of 200 seconds with the B filter starting 84 seconds after the BAT trigger. There is a candidate afterglow in the list of sources generated on-board at (RA,DEC) (J2000) of (286.4270,70.3760) or (19h 05m 42.48s,+70d 22' 33.6") with a 1-sigma error radius of about 0.5 arc sec. This position is 3.6 arc sec. from the center of the XRT error circle. The estimated V magnitude is 17.2 with a 1-sigma error of about 0.5 mag. No correction has been made for the expected visual extinction of about 0.4 magnitudes. This source was detected in a 200 sec B finding chart image taken beginning at 20:20:34 UT with a B magnitude of 19.55. We did not receive the V finding chart through TDRSS, so are unable to confirm the V magnitude from the V parameterized source list. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4488 SUBJECT: GRB 060111B: ROTSE-III Detection of Optical Counterpart Flare DATE: 06/01/11 21:25:14 GMT FROM: Sarah Yost at U.Michigan S.A. Yost, F. Yuan, H. Swan, C. Akerlof (U Mich), report on behalf of the ROTSE collaboration: ROTSE-IIId, located at the Turkish National Observatory at Bakirlitepe, Turkey, responded to GRB 060111B (Swift trigger 176918). The first image was at 20:16:12 UT, 29 s after the burst (9 s after the GCN notice time). The unfiltered images are calibrated relative to USNO A2.0. We detect an optical flare at the position of the UVOT optical counterpart (GCN 4487). It was observed initially at 13.0 mag, fading at least as rapidly as ~ t^-2.6. We detect it in 3 5-sec images and it has faded to or below the limiting magnitude of 15.5 in the 4th image at 69 sec post-burst. start UT mag mlim(of image) ---------------------------------- 20:16:12 13.0 15.2 20:16:52 >~15.5 15.5 A jpeg image is available at http://www.rotse.net/images/gsb176918_3d00_img.jpg //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4489 SUBJECT: GRB 060111B: Gualba observatory limit DATE: 06/01/11 23:36:38 GMT FROM: Martin Jelinek at Inst.Astrophys.Andalucia,Granada Albert Sanchez Caso (Gualba observatory, Spain), Martin Jelinek and Alberto J. Castro-Tirado (IAA CSIC Granada) on behalf of a larger colaboration report: We have observed the field of GRB060111B (Perri et al., GCN 4487) with a 12" telescope at Gualba observatory in Spain. We do not detect the afterglow seen by Yost et al. (GCN 4488) on our 30x30s R-band combined image with mid-exposure time 21:59:40 UT (i.e. ~1.75h after the GRB) and 3-sigma limit 19.2. No further observations are expected from spanish ground-based telescopes due to technical and weather constraints. This message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4490 SUBJECT: GRB 060111(a): P60 Observations DATE: 06/01/12 01:22:35 GMT FROM: S. Bradley Cenko at Caltech S. B. Cenko, A. M. Soderberg, E. Ofek (Caltech) and D. B. Fox (Penn State) report on behalf of the Caltech-NRAO-Carnegie Collaboration: We have imaged the field of GRB 060111(a) (Zane et al., GCN 4479) with the automated Palomar 60-inch telescope. Observations consisted of 9 x 180 s exposures in the Kron R-band taken at a mean epoch of 13:19:49 11 January UT (~ 8.9 hours after the burst trigger). We find no sources in the revised XRT error circle (Goad et al., GCN 4481) or at the location of the proposed UVOT counterpart (Blustin, Zane, and Rosen, GCN 4482). The limiting magnitude of our observations, calculated with respect to several Guide Star Catalog sources in the field, is R > 20.5. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4492 SUBJECT: GRB 060111B: Refined analysis of the Swift-BAT burst DATE: 06/01/12 03:10:05 GMT FROM: Scott Barthelmy at NASA/GSFC J. Tueller (GSFC), L. Barbier (GSFC), S. Barthelmy (GSFC), J. Cannizzo (GSFC-UMBC), L. Cominsky (Sonoma State U.), J. Cummings (GSFC/NRC), E. Fenimore (LANL), N. Gehrels (GSFC), D. Hullinger (GSFC/UMD), H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD), D. Palmer (LANL), A. Parsons (GSFC), T. Sakamoto (GSFC/NRC), G. Sato (ISAS) on behalf of the Swift-BAT team: Using the partial data set (T-60.2 to T+122.9 sec) from the recent telemetry downlink, we report further analysis of BAT GRB 060111 (trigger #176918) (Perri, et al., GCN 4487). The BAT ground-calculated position is RA,Dec = 286.460,+70.382 deg {19h 5m 50.4s,+70d 22' 54.0"} (J2000) +- 1.6 arcmin, (radius, sys+stat, 90% containment). The partial coding was 29%. The mast-weighted lightcurve shows two peaks. The first one starts at T-4 sec, peaks at T+1, and extends out to T+28 sec. The second, smaller peak starts at T+53, peaks at T+55, and is over by T+62 sec. T90 (15-350 keV) is 59 +- 1) sec (estimated error including systematics). The power law index of the time-averaged spectrum (T-2 to T+63 sec) is 1.04 +- 0.17. The fluence in the 15-150 keV band is (1.6 +- 0.1) x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+0.36 sec in the 15-150 keV band is 1.4 +- 0.3 ph/cm2/sec. All the quoted errors are at the 90% confidence level. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4495 SUBJECT: GRB 060111B: TAROT optical observation DATE: 06/01/12 14:22:29 GMT FROM: Alain Klotz at CESR-CNRS Klotz, A. (CESR-OMP), Boer M. (OHP), Atteia J.L. (LATT-OMP) report: We imaged the field of GRB 060111B detected by SWIFT (trigger 176918) with the TAROT robotic telescope (D=25cm) located at the Calern observatory, France. First image was acquired 28s after the GCN trigger (8s after the notice). The field elevation decreased from 28 degrees above horizon and weather conditions were good. We detected the OT source mentioned by Yost et al. (GCNC 4488) at the position (+/- 0.6 arcsec): RA(J2000.0) = 19 05 42.46 DEC(J2000.0) +70 22 32.3 OT was R~13.8 at 28s after GRB with a fading rate t^-1.74 (+/-0.1) until 200s. Magnitudes were estimated with the nearby USNO-B1 star: 1603-125792 (R=15.00). This message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4496 SUBJECT: GRB 060111B: MITSuME detection of optical afterglow DATE: 06/01/12 14:55:54 GMT FROM: Nobuyuki Kawai at Tokyo Tech K. Yanagisawa (OAO/NAOJ), H. Toda, and N. Kawai (Tokyo Tech) report on behalf of the MITSuME collaboration: "We have observed the field of GRB 060111B (Perri et al. GCN 4487, Tueller et al. GCN 4492) with the three-color MITSuME 50 cm telescope at Okayama, Japan starting at 20:26:18 UT (T_burst+10.6 min) for an effective exposure of 45 min (60sec x 45). Comparison of the two stacked images at midtime 20:28:56 UT (T_burst+13.2min, exp=60sec x5) and at midtime 20:56:26 UT (T_burst+40.7min, exp=60sec x5) revealed a fading object at the same location in the Rc and Ic band images. The coordinates of the fading object are: RA 19:05:42.47, DEC +70:22:33.1 (error = 0.3 arcsec) We identify this object as the optical afterglow of GRB 05111B for the following reasons: 1) these coordinates are consistent with those of the UVOT afterglow candidate by Perri et al. (GCN 4487), and 2) while we do not confirm the possible host galaxy noted by Khamitov et al. (GCN 4493) in our images, it is not likely to confuse our identification as it is 4.2 arcsec away. The magnitudes of the OT at midtime 20:28:56 UT (T_burst+13.2min) were following:  g': > 19.1 (3 sigma detection limit) Rc: 18.9 +/- 0.4 Ic: 18.3 +/- 0.4 The Rc and Ic magnitudes were calibrated with the R2 and I2 magnitudes of the USNO-B1.0 stars. The g' magnitudes was derived from the NOMAD B, V magnitudes using the formula by Smith et al. (2002). The images obtained at Okayama can be viewed at http://bragi.oao.nao.ac.jp/support/telescope/grb50/images/GRB060111B.pdf" //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4493 SUBJECT: GRB060111B: RTT150, possible host galaxy DATE: 06/01/12 06:10:18 GMT FROM: Irek Khamitov at TUG I. Khamitov, K. Uluc, Z. Aslan (TUG), U. Kiziloglu (METU), E. Gogus (Sabanci Uni.), T. Saygac, O. Onal (Ist. Uni.), R. Burenin, M. Pavlinsky, R. Sunyaev (IKI), I. Bikmaev, N. Sakhibullin (KSU/AST) report: We observed field around position of optical counterpart (Perri et al., GCN4487, Yost et al, GCN4488) of GRB060111B (Swift trigger 176918) with Russian-Turkish 1.5-m telescope (RTT150, Bakyrlytepe, TUBITAK National Observatory, Turkey), starting at Jan. 12, 02:11UT, i.e. ~5.9 hours after the burst. A series of frames (13*300s exposures in R bands) were taken. We did not detect OT, but detect an extended source on about 5 arcsec NW from OT position with coordinates: RA= 19h05m43.0s (J2000.0) DEC=+70d22'29."8 (J2000.0) Using USNO-B1 stars we estimate the following magnitude for this source: R=20.52+/-0.03, and limiting magnitude of combined image as: R~22.6 The finding chart can be found at: http://www.tug.tubitak.gov.tr/~irekk/grb/grb060111b/grb060111B.JPG This message may be cited. [GCN OPS NOTE(12jan06): See correction in Circular 4494.] //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4494 SUBJECT: GRB060111A: RTT150 optical observations DATE: 06/01/12 08:57:42 GMT FROM: Irek Khamitov at TUG I. Khamitov, K. Uluc, Z. Aslan (TUG), U. Kiziloglu (METU), E. Gogus (Sabanci Uni.), T. Saygac, O. Onal (Ist. Uni.) R. Burenin, M. Pavlinsky, R. Sunyaev (IKI) I. Bikmaev, N. Sakhibullin (KSU/AST) report: We observed field around of possible optical counterpart (Blustin et al., GCN4482) of GRB060111A (Swift trigger 176818) with Russian-Turkish 1.5-m telescope (RTT150, Bakyrlytepe, TUBITAK National Observatory, Turkey), starting on Jan. 12, 03:37UT, i.e. ~23.2 hours after the burst. A series of frames (8*300s exposures in R band) were taken. The afterglow candidate was detected only marginally near the detection limit of our combined image, which is estimated as R~23.2 (photometry is USNO-B1 calibrated). We also note that at about 5 arcsec from the OT we detected an extended source whith R=21.75+/-0.1, which may be a host galaxy of the GRB. The coordinates of this galaxy are RA= 18h24m49.01s (J2000.0) DEC=+37d36'09."6 (J2000.0). The finding chart can be found at: http://www.tug.tubitak.gov.tr/~irekk/grb/grb060111a/grb060111A.JPG Also we have to do a correction to GCN4493: We detected extended source in direction to SE, not NW. The upper limit for the GRB060111B OT is also actually deeper: R=~23.6 (the difference is due to corrected error in photometric calibration). This message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4497 SUBJECT: GRB 060111A: refined UVOT anaysis DATE: 06/01/12 16:27:17 GMT FROM: Alexander Blustin at MSSL-UCL S. R. Rosen (UCL-MSSL), S. Zane (UCL-MSSL), A. J. Blustin (UCL-MSSL), K. Hurley (Berkeley), M. Chester (PSU), N. Gehrels (GSFC) on behalf of the Swift/UVOT team Further analysis of the Swift/UVOT data for GRB 060111A (Zane et al., GCN 4479) reveals that the afterglow candidate reported by Blustin et al. (GCN 4482) in the initial UVOT V-band exposure has faded from view in subsequent data. The 3 sigma magnitude upper limits from later summed images in the different filters are as follows: Filter T_range(s) Exp(s) 3sigUL(mag) V 3750-4105 59 18.5 V 4757-10346 472 19.6 B 280-17141 1746 21.2 U 6042-16227 1476 20.8 W1 5838-21553 1033 20.3 M2 5633-10550 572 20.1 W2 9942-12104 435 20.1 These magnitudes are uncorrected for Galactic extinction. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4498 SUBJECT: GRB 060111B: Swift XRT refined analysis DATE: 06/01/12 18:37:21 GMT FROM: Matteo Perri at ISAC/ASDC M. Perri (ASDC), A. Moretti (OAB), D. N. Burrows (PSU), R. Fink (GSFC), M. Ajello (MPE) report on behalf of the Swift XRT team: We have analyzed the first 6 orbits of XRT data from GRB 060111B (trigger 176918, GCN 4487). A ~13 ks Photon Counting mode image provides a refined XRT position: RA(J2000) = 19h 05m 42.23s, Dec(J2000) = +70d 22m 35.8s with an uncertainty of 3.6 arcsec (90% containment). This position is 1.1 arcsec away from the on-board XRT position (GCN 4487) and includes the latest XRT boresight correction. This position is 45 arcsec from the refined BAT position (Tueller et al., GCN 4492) and 3.0 arcsec from the optical afterglow reported by Yanagisawa et al. (GCN 4496). The X-ray light curve can be fit with a broken power-law with an initial decay slope of -4.0+/-0.4, a break at T+139+/-7 s, and a post-break slope of -1.1+/-0.1. A power-law fit to the X-ray spectrum from T+88s to T+425s gave a photon index of 2.1+/-0.3 and a column density of (2.0+/-0.9)e21 cm**-2. We note the Galactic hydrogen column density in the direction of the burst is 7.1e20cm**-2. If the burst continues decaying at the current rate we estimate an XRT count rate of 0.004 counts/s at T+24hr, which corresponds to an observed 0.3-10.keV flux of 2e-13 ergs cm**-2 s**-1. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4571 SUBJECT: GRB 060111B: Suzaku WAM observation of the prompt emission DATE: 06/01/24 17:36:05 GMT FROM: Kazutaka Yamaoka at Aoyama Gakuin U G.Sato, K.Nakazawa, T.Takahashi (ISAS/JAXA), K.Yamaoka, S.Sugita (Aoyama Gakuin U.), Y.Terada (RIKEN), M.Ohno, T.Takahashi, Y.Fukazawa (Hiroshima U.), K.Abe, Y.Endo, S. Hong, K.Onda, M.Tashiro (Saitama U.), R.Miyawaki, M.Kokubun, K.Makishima (Univ. of Tokyo) and the HXD-II team The long burst, GRB 060111B (Swift-BAT trigger #176918; Perri et al., GCN 4487), triggered the Suzaku Wide-band All-sky Monitor (WAM) which is sensitive to an energy band of 50 keV - 5 MeV at 20:15:41 (UT). The WAM light curve exhibits a double peak structure with a duration (T90) of 25 seconds. The fluence in 100 - 1000 keV was (5.6 +/- 0.8)X10^-6 erg/cm2. The 1-s peak flux was 1.0 +/- 0.2 photons/cm2/s in the same energy range. Preliminary result shows that the time-averaged spectrum is well fitted by a single power law with a photon index of 1.5 +/- 0.3. All the quoted errors are at statistical 90% confidence level. The WAM in-flight calibration is still under way, and systematic errors, such as the flux calibration uncertainties of about 20%, are not included in the errors. The WAM light curve of this event is available at http://www.astro.isas.ac.jp/suzaku/research/HXD-WAM/WAM-GRB/grb/grb_table.html Further detailed analysis and the refinement are in progress. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 5820 SUBJECT: GRB 060111B: Swift UVOT Refined Magnitudes DATE: 06/11/13 14:13:58 GMT FROM: Stephen Holland at USRA/NASA/GSFC/SSC S. T. Holland (NASA/GSFC & USRA) reports on behalf of the UVOT team: The UVOT data for GRB 060111B (Perri, et al. 2006, GCN Circ. 4487) on January 11, 2006 has been reanalysed. We find the following magnitudes and 3-sigma upper limits in the early UVOT exposures. The start and stop times are relative to the BAT trigger time, 20:15:43 UT. Filter Start Stop Exposure Mag Err (s) (s) (s) Early Exposures V 83 282 197 17.4 0.1 V 542 562 19 18.0 3-sigma upper limit V 831 1031 197 19.4 3-sigma upper limit B 289 489 197 20.5 3-sigma upper limit B 638 658 19 18.9 3-sigma upper limit U 614 633 19 18.4 3-sigma upper limit UVW1 590 610 19 18.0 3-sigma upper limit UVM2 6017 6217 197 20.0 3-sigma upper limit UVW2 518 538 19 17.5 3-sigma upper limit White 494 514 19 19.4 3-sigma upper limit Coadded Esposures V 542 52472 2435 21.0 3-sigma upper limit B 638 70515 5861 22.4 3-sigma upper limit U 614 69818 6008 22.0 3-sigma upper limit UVW1 590 68905 4089 22.2 3-sigma upper limit UVM2 566 53170 3663 22.2 3-sigma upper limit UVW2 519 58952 3662 22.4 3-sigma upper limit White 494 64734 3696 22.2 3-sigma upper limit The values quoted above are not corrected for the expected Galactic extinction of E_{B-V} = 0.11 mag (Schlegel et al. 1998). These data supercede those reported in GCN Circ. 4487. We note that the B-band detection reported in GCN Circ. 4487 is not real, and the initial finding chart was taken with the V filter, not the B filter as previously reported. The UVOT team apologizes for these errors.