GRB080906A

This page lists all entries on GRB080906A in GRBweb

Summary IPN Swift GCN 8186 GCN 8194 GCN 8196 GCN 8197 GCN 8198 GCN 8216

Summary table
Variable Value Source
T0 13:33:16 UTC GCN_circulars,Swift Det
ra 228.0444° Swift
decl -80.5176° Swift
pos_error 8.28e-05° Swift
T90 147.0 s Swift
T90_start 13:33:16 UTC Swift
fluence 3.50e-06 erg/cm² Swift
redshift 2.0000 Swift
T100 147.0 s
GBM_located False
mjd 54715.56476851852 GCN_circulars,Swift Det
IPN table
GRB_name GRB080906A
ra 227.8917°
decl -80.4833°
pos_error 5.00e-02°
Swift table
GRB_name GRB080906A
t_trigger 13:33:16 UTC
ra 228.0444°
decl -80.5176°
pos_error 8.28e-05°
T90 147.0 s
fluence 3.50e-06 erg/cm²
redshift 2.0000
GCN 8186 table
GRB_name GRB080906A
GCN_number 8186
Detection_method Swift Det
t_trigger 13:33:16 UTC
ra 227.8900°
decl -80.4860°
Circular_text TITLE: GCN CIRCULAR NUMBER: 8186 SUBJECT: GRB 080906: Swift detection of a burst with optical afterglow DATE: 08/09/06 13:52:03 GMT FROM: David Burrows at PSU/Swift L. Vetere (PSU), S. D. Barthelmy (GSFC), P. J. Brown (PSU), D. N. Burrows (PSU), M. M. Chester (PSU), N. Gehrels (NASA/GSFC), S. T. Holland (CRESST/USRA/GSFC), H. A. Krimm (CRESST/GSFC/USRA), J. Mao (INAF-OAB), C. B. Markwardt (CRESST/GSFC/UMD), F. E. Marshall (NASA/GSFC), P. T. O'Brien (U Leicester), D. M. Palmer (LANL), J. L. Racusin (PSU), B. Sbarufatti (INAF-IASFPA), M. Stamatikos (NASA/ORAU), G. Tagliaferri (INAF-OAB), E. Troja (INAF-IASFPA) and T. N. Ukwatta (GSFC/GWU) report on behalf of the Swift Team: At 13:33:16 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 080906 (trigger=323984). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 227.890, -80.486 which is RA(J2000) = 15h 11m 34s Dec(J2000) = -80d 29' 09" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed one major peak of duration ~50 sec, with possible smaller peaks. The peak count rate was ~2000 counts/sec (15-350 keV), at ~10 sec after the trigger. The XRT began observing the field at 13:34:27.6 UT, 71.3 seconds after the BAT trigger. XRT found a bright, fading, uncatalogued X-ray source located at RA, Dec 228.0514, -80.5183 which is equivalent to: RA(J2000) = 15h 12m 12.3s Dec(J2000) = -80d 31' 05.8" with an uncertainty of 4.7 arcseconds (radius, 90% containment). This location is 150 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. UVOT took a finding chart exposure of 100 seconds with the White (160-650 nm) filter starting 82 seconds after the BAT trigger. There is a candidate afterglow in the rapidly available 2.7'x2.7' sub-image at RA(J2000) = 15:12:10.63 = 228.0443 DEC(J2000) = -80:31:04.1 = -80.5178 with a 1-sigma error radius of about 0.5 arc sec. This position is 4.6 arc sec. from the center of the XRT error circle. The estimated magnitude is 19.7 with a 1-sigma error of about 0.5 mag. No correction has been made for the expected extinction corresponding to E(B-V) of 0.30.
GCN 8194 table
GRB_name GRB080906A
GCN_number 8194
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 8194 SUBJECT: GRB 080906: GROND observations of the optical/NIR afterglow DATE: 08/09/07 09:44:25 GMT FROM: Paulo M. J. Afonso at MPE GRB 080906: GROND observations of the optical/NIR afterglow P.Afonso, T. Kruehler, J. Greiner, C.Clemens, A. Yoldas (all MPE Garching) and A. Kuepcue Yoldas (ESO) report on behalf of the GROND team: We observed the field of GRB 080906 (Swift trigger 323984; L. Vetere et al., GCN #8186), simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, PASP 120, 405) mounted at the 2.2m ESO/MPI telescope at La Silla Observatory (Chile). Observations started at 00:12 UT on September 7th, 2008, 10.7 hrs after the GRB trigger.We detect the optical afterglow reported by L. Vetere et al. (GCN #8186) at a position consistent with the UVOT detection in all bands, implying a redshift smaller than 3.5. Preliminary photometry yields the following magnitudes calibrated against USNO-B1 and 2MASS field stars in stacked images: Band Exp(min) Mag g' 24 22.2 +- 0.1 r' 24 21.4 +- 0.1 i' 24 21.2 +- 0.1 z' 24 21.2 +- 0.1 J 20 20.2 +- 0.1 H 20 19.2 +- 0.1 K 20 18.5 +- 0.1 not corrected for the expected Galactic foreground reddening of E(B-V) = 0.30 mag (Schlegel et al., 1998).
GCN 8196 table
GRB_name GRB080906A
GCN_number 8196
Detection_method Swift-BAT Det
ra 228.0550°
decl -80.5400°
Circular_text TITLE: GCN CIRCULAR NUMBER: 8196 SUBJECT: GRB 080906, Swift-BAT refined analysis DATE: 08/09/07 17:40:23 GMT FROM: Scott Barthelmy at NASA/GSFC M. Stamatikos (GSFC/ORAU), S. D. Barthelmy (GSFC), W. Baumgartner (GSFC/UMBC), J. Cummings (GSFC/UMBC), E. Fenimore (LANL), N. Gehrels (GSFC), H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD), K. McLean (GSFC/UMD), D. Palmer (LANL), T. Sakamoto (GSFC/UMBC), G. Sato (ISAS), J. Tueller (GSFC), T. Ukwatta (GWU), L. Vetere (PSU) (i.e. the Swift-BAT team): Using the data set from T-239 to T+963 sec from recent telemetry downlinks, we report further analysis of BAT GRB 080906 (trigger #323984) (Vetere, et al., GCN Circ. 8186). The BAT ground-calculated position is RA, Dec = 228.055, -80.540 deg, which is RA(J2000) = 15h 12m 13.3s Dec(J2000) = -80d 32' 24.9" with an uncertainty of 1.7 arcmin, (radius, sys+stat, 90% containment). The partial coding was 58%. The mask-weighted light curve shows a roughly symmetrical peak starting at ~T-100 sec, peaking around T+10 sec, and tailing off to about T+100 sec. T90 (15-350 keV) is 147 +- 21 sec (estimated error including systematics). The time-averaged spectrum from T-105 to T+104 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.59 +- 0.09. The fluence in the 15-150 keV band is 3.5 +- 0.2 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T-0.06 sec in the 15-150 keV band is 1.0 +- 0.2 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/323984/BA/
GCN 8197 table
GRB_name GRB080906A
GCN_number 8197
Detection_method Swift-XRT Other
ra 228.0421°
decl -80.5179°
Circular_text TITLE: GCN CIRCULAR NUMBER: 8197 SUBJECT: GRB 080906: Swift-XRT Refined Analysis DATE: 08/09/07 20:20:43 GMT FROM: Loredana Vetere at PSU L. Vetere, J.L. Racusin, C. Pagani (PSU), J.P. Osborne, A.P. Beardmore, P.A. Evans and M.R. Goad (U. Leicester) report on behalf of the Swift-XRT team: The XRT began observing the field of GRB 080906 (trigger=323984; Vetere et al., GCN Circ 8186) at 13:34:27.6 UT, 71.3 seconds after the BAT trigger. Using 1224 s of XRT Photon Counting mode data and 2 UVOT images, we find an astrometrically corrected X-ray position (using the XRT-UVOT alignment and matching to the USNO-B1 catalogue): RA, Dec = 228.04211, -80.51787 which is equivalent to: RA (J2000): 15 12 10.11 Dec (J2000): -80 31 04.3 with an uncertainty of 1.8 arcsec (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 http://www.swift.ac.uk/xrt_positions/Goad.pdf), the current algorithm is an extension of this method. This position is 80 arcsec away from the ground-processed BAT position given in GCN Circ. 8196 (Stamatikos et al.) inside BAT error circle. The WT mode lightcurve shows a number of flares, with the strongest peaking around 186, 598 and 907 s after the trigger. The PC data in later orbits shows some flaring activity and decays as a single power-law with alpha = 1.25 +/- 0.11. The WT spectrum of the first 80 s (before the first peak) can be fitted with a power-law of Gamma = 1.82 +/-0.08 and absorption consistent with the Galactic value along the line of sight (9.7x10^20 cm^-2). The observed (unabsorbed) flux over this time is 1.98 (2.7)x10^-9 erg cm^-2 s^-1. A spectrum extracted from the PC mode data (11.6-75.6 ks after the trigger) can be fitted with a power-law of Gamma = 2.3 +0.1/-0.2 and total NH = (1.7 +/- 0.5)x10^22 cm^-2, slightly in excess of the Galactic value. The observed (unabsorbed) flux over this time is 1.7 (3.1)x10^-11 erg cm^-2 s^-1. If the decay continues with alpha = 1.25, the predicted count-rate at 48 hours is 0.007 count s^-1, corresponding to an observed (unabsorbed) flux of 2.6 (4.8)x10^-13 erg cm^-2 s^-1. This Circular is an official product of the Swift-XRT team.
GCN 8198 table
GRB_name GRB080906A
GCN_number 8198
Detection_method Swift-UVOT Det
ra 228.0444°
decl -80.5176°
Circular_text TITLE: GCN CIRCULAR NUMBER: 8198 SUBJECT: GRB 080906: Refined Swift/UVOT Observations DATE: 08/09/07 22:00:22 GMT FROM: Stephen Holland at USRA/NASA/GSFC/SSC S. T. Holland (CRESST/USRA/GSFC) & L. Vetere (PSU) report on behalf of the Swift/UVOT team: The Swift/UVOT observed the field of GRB 080906 starting 62 s after the BAT trigger (Vetere et al., 2008, GCNC. 8186). Settled observations started at T + 82 s. We detect the optical afterglow (Vetere et al., GCNC 8186) in the v, b, u, and white filters. The refined UVOT source position is RA (J2000) = 15:12:10.65 Dec (J2000) = -80:31:03.2 with an estimated uncertainty of 0.64 arcsec (radius, 90% confidence). Magnitudes and upper limits are reported below. Filter TSTART TSTOP Exposure Mag Err Comment white 82 182 98 19.71 0.15 v 188 588 393 18.61 0.12 b 668 6204 216 21.02 0.44 u 643 5998 236 20.37 0.34 uvw1 619 5793 236 >20.9 2-sigma upper limit uvm2 594 5588 236 >20.5 2-sigma upper limit uvw2 698 6614 235 >21.1 2-sigma upper limit The above magnitudes are not corrected for the Galactic extinction corresponding to a reddening of E_{B-V} = 0.30 mag (Schlegel et al., 1998, ApJS, 500, 525). The photometry is on the UVOT photometric system described in Poole et al. (2008, MNRAS, 383,627). The detection in the u filter, coupled with the non-detections in the uvw1, uvm2, and uvw2 filters, are consistent with a redshift of approximately z < 2.6. The power-law decay index in the v band between 338 and 6719 s is -0.50 +/- 0.04. Please update my e-mail address in your Address Book to . / \ /
GCN 8216 table
GRB_name GRB080906A
GCN_number 8216
Detection_method Swift Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 8216 SUBJECT: GRB 080906: Watcher observations DATE: 08/09/12 13:41:43 GMT FROM: Alejandro Ferrero at U College,Dublin Alejandro Ferrero (UCD School of Physics), John French (UCD School of Physics, DARK/NBI), Gary Melady (UCD School of Physics) report on behalf of a larger collaboration: The Watcher 40 cm robotic telescope at Boyden Observatory, South Africa, began imaging the field of GRB 080906 (Vetere et al. GCN 8186) at 16:51:15.5 UT, 3.6 h after the Swift triggger. We do not detect the afterglow reported by Holland et al. (GCN 8198) and Afonso et al. (GCN 8194). Our first 120s exposure has a limiting magnitude of 16.9, while a stacked sequence of 10 120s images, with an exposure mid-time of 3.8 hrs after the trigger, results in a limiting magnitude of 18.4. Unfiltered magnitudes are transformed to R-band by comparison with the USNO-B1 catalog.