GRB080804A

This page lists all entries on GRB080804A in GRBweb

Summary Fermi GBM IPN Swift GCN 8056 GCN 8057 GCN 8058 GCN 8064 GCN 8065 GCN 8066 GCN 8067 GCN 8069 GCN 8070 GCN 8073 GCN 8075

Summary table
Variable Value Source
GRB_name_Fermi GRB080804972
T0 23:20:14 UTC GCN_circulars,Swift Det
ra 328.6675° Swift
decl -53.1846° Swift
pos_error 5.18e-05° Swift
T90 24.704 s Fermi_GBM
T90_error 1.46 s Fermi_GBM
T90_start 23:20:15.135 UTC Fermi_GBM
fluence 9.13e-06 erg/cm² Fermi_GBM
fluence_error 1.06e-07 erg/cm² Fermi_GBM
redshift 2.2045
T100 34.0 s
GBM_located False
mjd 54682.97238425926 GCN_circulars,Swift Det
Fermi GBM table
GRB_name_Fermi GRB080804972
trigger_name bn080804972
ra 328.7000°
decl -53.2000°
pos_error 3.06e+00°
datum 2008-08-04
t_trigger 23:20:14.879 UTC
T90 24.704 s
T90_error 1.46 s
T90_start 23:20:15.135 UTC
fluence 9.13e-06 erg/cm²
fluence_error 1.06e-07 erg/cm²
flux_1024 3.85e+00 erg/cm²/s
flux_1024_error 1.65e-01 erg/cm²/s
flux_1024_time 1.02e+00 erg/cm²/s
flux_64 5.81e+00 erg/cm²/s
flux_64_error 7.64e-01 erg/cm²/s
IPN table
GRB_name GRB080804A
ra 328.7000°
decl -53.2000°
pos_error 5.00e-02°
redshift 2.2045
Swift table
GRB_name GRB080804A
t_trigger 23:20:14 UTC
ra 328.6675°
decl -53.1846°
pos_error 5.18e-05°
T90 34.0 s
fluence 3.60e-06 erg/cm²
redshift 2.2045
GCN 8056 table
GRB_name GRB080804A
GCN_number 8056
Detection_method Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 8056 SUBJECT: GRB 080804: ROTSE-III Detection of Optical Counterpart DATE: 08/08/04 23:28:02 GMT FROM: Wiphu Rujopakarn at U AZ/Steward W. Rujopakarn (Steward), E.S. Rykoff (UCSB) report on behalf of the ROTSE collaboration: ROTSE-IIIc, located at the H.E.S.S. site at Mt. Gamsberg, Namibia, responded to GRB 080804 (Swift trigger 319016). The first image was at 23:20:34.3 UT, 19.6 s after the burst (6.3 s after the GCN notice time). The unfiltered images are calibrated relative to USNO A2.0. We detect a 17.2 magnitude, brightening source with coordinates: 21:54:40.1 -53:11:03.8 (J2000), with positional uncertainty of 1" or better start UT mag mlim(of image) ---------------------------------- 23:20:50.2 17.2 16.9 This source is not visible in DSS (second epoch), 2MASS or the MPChecker database. A jpeg image is available at http://www.rotse.net/images/gsb319016_3c01_img.jpg Note that the object marked 38 is the candidate in question. Continuing observations are in progress.
GCN 8057 table
GRB_name GRB080804A
GCN_number 8057
Detection_method Swift Det
t_trigger 23:20:14 UTC
ra 328.7010°
decl -53.1950°
Circular_text TITLE: GCN CIRCULAR NUMBER: 8057 SUBJECT: GRB 080804: Swift detection of a burst with optical afterglow DATE: 08/08/04 23:37:27 GMT FROM: Scott Barthelmy at NASA/GSFC J. L. Racusin (PSU), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), M. M. Chester (PSU), N. Gehrels (NASA/GSFC), D. Grupe (PSU), S. T. Holland (CRESST/USRA/GSFC), J. A. Kennea (PSU), C. Pagani (PSU), D. M. Palmer (LANL), M. C. Stroh (PSU) and T. N. Ukwatta (GSFC/GWU) report on behalf of the Swift Team: At 23:20:14 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 080804 (trigger=319016). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 328.701, -53.195 which is RA(J2000) = 21h 54m 48s Dec(J2000) = -53d 11' 40" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve shows multiple overlapping peaks with a duration of about 20 sec. The peak count rate was ~1500 counts/sec (15-350 keV), at ~3 sec after the trigger. The XRT began observing the field at 23:21:53.7 UT, 99.0 seconds after the BAT trigger. Using promptly downlinked data we find a bright, uncatalogued X-ray source located at RA, Dec 328.66583, -53.18532 which is equivalent to: RA(J2000) = 21h 54m 39.80s Dec(J2000) = -53d 11' 07.2" with an uncertainty of 3.0 arcseconds (radius, 90% containment). This location is 83 arcseconds from the BAT onboard position, within the BAT error circle. A power-law fit to a spectrum formed from promptly downlinked event data gives a column density consistent with the Galactic value of 1.63e+20 cm^-2 (Kalberla et al. 2005). The initial flux in the 2.5 s image was 5.50e-10 erg cm^-2 s^-1 (0.2-10 keV). UVOT took a finding chart exposure of nominal 100 seconds with the White (160-650 nm) filter starting 109 seconds after the BAT trigger. There is a candidate afterglow in the list of sources generated on-board at RA(J2000) = 21:54:40.2 = 328.6675 DEC(J2000) = -53:11:05 = -53.18472 with a 1-sigma error radius of about 1.0 arc sec. The estimated white magnitude is 16.8 with a 1-sigma error of about 0.5 mag. No correction has been made for a Galactic extinction corresponding to a reddening of 0.02 mag along the line of sight. Burst Advocate for this burst is J. L. Racusin (racusin AT astro.psu.edu). 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.)
GCN 8058 table
GRB_name GRB080804A
GCN_number 8058
Detection_method Other
redshift 2.2045
Circular_text TITLE: GCN CIRCULAR NUMBER: 8058 SUBJECT: GRB 080804: UVES redshift DATE: 08/08/05 03:21:55 GMT FROM: Antonio Deugarte at IAA-CSIC Christina C. Thoene (DARK/NBI), Antonio de Ugarte Postigo (ESO), PaulM. Vreeswijk, Daniele Malesani (DARK/NBI), Palli Jakobsson (Univ. Hertfordshire) report on behalf of a larger collaboration: We observed the afterglow of GRB 080804 (Racusin et al., GCN 8057; Rujopakarn & Rykoff, GCN 8056) with the UVES high-resolution spectrograph at the VLT. Observations started on 2008 Aug 5.008 UT (50 min after the GRB). We obtained two spectra with exposure times of 30 and 45 minutes. The spectra cover the wavelength range from 3500 to 9460 Angstroms. We detect a strong DLA as well as a large range of absorption lines including SiII, SII, OI, CII, AlII, MgI and SiII* from which we derive a redshift of z=2.2045. We acknowledge excellent support from the observing staff at Paranal, including Swetlana Hubrig, Thomas Rivinius, and Yuri Belestky. We are especially indebted to Swetlana Hubrig and Martin Netopil for using part of their telescope time.
GCN 8064 table
GRB_name GRB080804A
GCN_number 8064
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 8064 SUBJECT: GRB 080804: Faulkes Telescope South observations DATE: 08/08/05 15:05:59 GMT FROM: Cristiano Guidorzi at INAF-OAB C. Guidorzi (INAF-OAB) and I. Steele (LJMU) on behalf of a larger collaboration report: On 2008 August 05 (12:44:12 UT) we began observing the field of GRB 080804 (Racusin et al. GCN Circ. 8057) with the Faulkes Telescope South using the R filter. In our coadded frame we detect the optical afterglow at the position fully consistent with that reported by Swift-UVOT (Racusin et al. GCN Circ. 8057) and slighly outside the error circle given by ROTSE-III (Rujopakarn et al. GCN Circ. 8056) which is 1.5 arcsec away. Telescope Filter T_mid[hr] Exposure[s] Mag ----------------------------------------------------------- FTS R 14.235 1200 21.6 +/- 0.1 ----------------------------------------------------------- The calibration was performed using the R2 magnitudes of several USNOB-1 catalogue field objects. The uncertainty reported above does not include the additional ~0.3 mag of the USNOB-1 catalogue. From the comparison with the value reported by UVOT we infer an average power-law decay index of ~0.7.
GCN 8065 table
GRB_name GRB080804A
GCN_number 8065
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 8065 SUBJECT: GRB080804: Gemini South redshift confirmation DATE: 08/08/05 15:34:42 GMT FROM: Antonino Cucchiara at PSU A. Cucchiara, D. B. Fox (Penn State), S. B. Cenko (Caltech) and E. Berger (Harvard U.) report on behalf of a larger collaboration: Starting at 01:27 UT on 2008 August 5 we observed the optical counterpart of GRB 080804 (Rujopakarn et al., GCN 8056, Racusin et al., GCN 8057) using Gemini-South with GMOS spectrograph (R~1200). We acquired 2x900s spectra which covered the wavelength range 4000A-8000A and 2x900s spectra covering the range 6000A-10000A. We detect some of the metal absorption features identified by Thoene et al. (GCN 8058), like FeII (1608, 2260), NiII (1741 and 1751) and we also detect MgII doublet (2796,2803). We also detect part of the red wing of the Lyman break indicating a possible DLA associated with the grb host galaxy. All these features confirm that the grb redshift is z = 2.20. We thank the Gemini staff for conducting these observations.
GCN 8066 table
GRB_name GRB080804A
GCN_number 8066
Detection_method Swift-XRT Det
ra 328.6676°
decl -53.1848°
Circular_text TITLE: GCN CIRCULAR NUMBER: 8066 SUBJECT: GRB 080804: Enhanced Swift-XRT position DATE: 08/08/05 15:42:09 GMT FROM: Phil Evans at U of Leicester A.P. Beardmore, P.A. Evans, M.R. Goad and J.P. Osborne (U. Leicester) report on behalf of the Swift-XRT team. Using 6979 s of XRT Photon Counting mode data and 8 UVOT images for GRB 080804, 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 = 328.66755, -53.18483 which is equivalent to: RA (J2000): 21h 54m 40.21s Dec (J2000): -53d 11' 05.4" with an uncertainty of 1.5 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 http://www.swift.ac.uk/xrt_positions/Goad.pdf), the current algorithm is an extension of this method. This circular was automatically generated, and is an official product of the Swift-XRT team.
GCN 8067 table
GRB_name GRB080804A
GCN_number 8067
Detection_method Swift-BAT Det
ra 328.6750°
decl -53.1890°
Circular_text TITLE: GCN CIRCULAR NUMBER: 8067 SUBJECT: GRB 080804, Swift-BAT refined analysis DATE: 08/08/05 15:54:46 GMT FROM: Scott Barthelmy at NASA/GSFC C. Markwardt (GSFC/UMD), S. D. Barthelmy (GSFC), W. Baumgartner (GSFC/UMBC), J. Cummings (GSFC/UMBC), E. Fenimore (LANL), N. Gehrels (GSFC), H. Krimm (GSFC/USRA), K. McLean (GSFC/UMD), D. Palmer (LANL), J. L. Racusin (PSU), T. Sakamoto (GSFC/UMBC), G. Sato (ISAS), M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC), T. Ukwatta (GWU) (i.e. the Swift-BAT team): Using the data set from T-240 to T+962 sec from recent telemetry downlinks, we report further analysis of BAT GRB 080804 (trigger #319016) (Racusin, et al., GCN Circ. 8057). The BAT ground-calculated position is RA, Dec = 328.675, -53.189 deg which is RA(J2000) = 21h 54m 41.9s Dec(J2000) = -53d 11' 20.2" with an uncertainty of 1.2 arcmin, (radius, sys+stat, 90% containment). The partial coding was 19%. The mask-weighted light curve shows the main peak starting at ~T-10sec, peaking at ~T+2 sec, and ending at ~T+100 sec. T90 (15-350 keV) is 34 +- 16 sec (estimated error including systematics). The time-averaged spectrum from T-0.4 to T+62.8 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.19 +- 0.09. The fluence in the 15-150 keV band is 3.6 +- 0.2 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+1.57 sec in the 15-150 keV band is 3.1 +- 0.4 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/319016/BA/
GCN 8069 table
GRB_name GRB080804A
GCN_number 8069
Detection_method Swift-UVOT Other
ra 328.6675°
decl -53.1846°
redshift 2.2045
Circular_text TITLE: GCN CIRCULAR NUMBER: 8069 SUBJECT: GRB 080804: Swift/UVOT Refined Analysis DATE: 08/08/05 18:29:58 GMT FROM: Paul Kuin at MSSL N. P. M. Kuin (MSSL/UCL), and J. L. Racusin (PSU), report on behalf of the Swift UVOT team The Swift UltraViolet/Optical Telescope (UVOT) began observations of GRB 080804, on August 4, 2008, at 23:21:45 UT, 91 seconds after the initial Swift BAT trigger (Racusin et al., GCN Circ. 8057), and started the finding chart exposure in the white filter at 111 seconds after the trigger. The refined uvot position of GRB080804 is RA=0328.66750 Dec=-53.18461 deg.(= 21:54:40.2 -53:11:04.6), with an accuracy of 0.4", consistent with the positions reported in GCN Circ. 8056 (Rujokaparn et al.), 8057 (Racusin et al.) and 8066 (Beardmore et al.). The magnitudes with 1-sigma errors for GRB080804 are given below for the initial observation sequence. Filter Tstart(s) Tstop(s) Exp(s) Magnitude wh 111 210 98.2 16.83 +/- 0.03 wh 711 720 9.6 18.3 +/- 0.16 v 217 616 393.5 17.17 +/- 0.05 v 752 771 19.4 17.85 +/- 0.30 uvm2 623 642 19.5 >17.6 (3 sigma UL) uvw1 648 667 19.4 >18.2 (3 sigma UL) b 697 706 9.6 18.1 +/- 0.27 u 672 691 19.4 17.4 +/- 0.17 uvw2 727 746 19.5 >18.2 (3 sigma UL) uvw1 648 7442 529.3 20.9 +/- 0.4 uvm2 623 7237 529.4 >20.8 (3 sigma UL) uvw2 727 6827 1179.5 >21.8 (3 sigma UL) The upper limits in uvw2, uvm2, and weak detection in uvw1 are consistent with the reported redshift of z=2.2045 by Thoene et al. (GCN Circ. 8058). The values quoted above are on the UVOT Photometric System (Poole et al, 2008, MNRAS 383,627). They are not corrected for the expected galactic reddening of E(B-V) = 0.016 in the direction of the burst (Schlegel et al. 1998).
GCN 8070 table
GRB_name GRB080804A
GCN_number 8070
Detection_method Swift-XRT Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 8070 SUBJECT: GRB 080804: Swift-XRT Refined Analysis DATE: 08/08/05 20:24:05 GMT FROM: Judith Racusin at PSU J. Racusin, C. Pagani (PSU) report on behalf of the Swift-XRT team: We have analysed the first five orbits of Swift-XRT data available for GRB 080804 (Racusin et al., GCN 8057) consisting of 123 s of WT mode data, and 11.0 ks of PC mode data. The enhanced XRT position is given in Beardmore et al. (GCN Circ. 8066). The preliminary 0.3-10.0 keV lightcurve can be fit with a single power-law with a decay index of 1.09+/-0.03. The WT and PC spectra can be jointly fit with an absorbed power-law with a photon index of 1.6 +/- 0.2. The intrinsic absorption is at a level of 1.7e21 cm^-2 (using z=2.2045, Thoene et al., GCN Circ. 8058), in addition to the Galactic absorption along the line of sight (1.6e20 cm^-2, Kalberla et al. 2005). The average observed (unabsorbed) flux is 2.5e-10 (2.6e-10) ergs cm^-2 s^-1 and 1.2e-11 (1.2e-11) ergs cm^-2 s^-1, for the WT and PC spectra respectively. Assuming the X-ray emission continues to decline at the same rate, we predict a 0.3-10.0 keV XRT count rate of 0.008 counts/s at T+24hr, which corresponds to an observed flux of 3.4e-13 ergs cm^-2 s^-1. This Circular is an official product of the Swift-XRT team.
GCN 8073 table
GRB_name GRB080804A
GCN_number 8073
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 8073 SUBJECT: GRB 080804: ATCA Radio Observations DATE: 08/08/06 03:36:41 GMT FROM: Alexander van der Horst at NASA/MSFC A.J. van der Horst (NASA/ORAU) and C. Kouveliotou (NASA/MSFC) report: "We observed the position of the GRB 080804 afterglow at 4.8 and 8.6 GHz with the Australia Telescope Compact Array at August 5 16.92 UT to 22.45 UT, i.e. 0.73 - 0.96 days after the burst (GCN 8057). We do not detect a radio source at the position of the optical afterglow (GCN 8056). The formal flux measurement for a point source at the location of the optical counterpart is -41 +/- 64 microJy at 4.8 GHz, and 40 +/- 63 microJy at 8.6 GHz. We would like to thank the staff of the Australia Telescope National Facility, in particular Angel Lopez-Sanchez and Philip Edwards, for scheduling and obtaining these Target of Opportunity observations."
GCN 8075 table
GRB_name GRB080804A
GCN_number 8075
Detection_method GROND
ra 328.6627°
decl -53.1829°
Circular_text TITLE: GCN CIRCULAR NUMBER: 8075 SUBJECT: GRB 080804: GROND observations DATE: 08/08/06 07:58:12 GMT FROM: Thomas Kruehler at MPE/MPI T. Kruehler, F. Schrey, J. Greiner, A. Yoldas, C. Clemens, S. McBreen (all MPE Garching), A. Kupcu Yoldas (ESO) and G. Szokoly (Eoetvoes Univ., Budapest) report on behalf of the GROND team: GROND (Greiner et al. 2008, PASP 120, 405), mounted at the 2.2m ESO/MPI telescope at La Silla Observatory (Chile), started observations of the field of GRB 080804 (Racusin et al. 2008, GCN #8057) in g'r'i'z'JHK at 23:26 UT, 16 min after the burst. We clearly detect the optical afterglow (Rujopakarn & Rykoff 2008, GCN #8056) in all filters at a position consistent with UVOT (Racusin et al. 2008, GCN #8057) and the Faulkes Telescope South (Guidorzi & Steele, GCN #8064). Observations continued for 65 min and were resumed at 06:30 UT for 30 min. Assuming the USNO-B1 star at RA(J2000)=328.6627, DEC(J2000)=-53.18288 having R2=18.08 mag, we measure the following r' magnitudes, not corrected for the expected Galactic foreground extinction corresponding to a reddening of E_(B-V)=0.02 (Schlegel et al. 1998): Filter T_mid Exposure Brightness (s) (s) (mag) ----------------------------------------- r' 1160 67 18.09 +- 0.03 r' 1565 67 18.37 +- 0.03 r' 1996 115 18.66 +- 0.02 r' 2768 115 18.96 +- 0.02 r' 3672 375 19.25 +- 0.02 r' 26112 375 21.02 +- 0.04 The reported magnitudes are a subset of the complete observation consisting of 24 individual frames. The total r band light curve is well fitted by power law with index of 0.87 +- 0.03 between 0.32 h and 7.63 h post burst. This decline is consistent with the Faulkes Telescope South detection (Guidorzi & Steele, GCN #8064) at 14.235 h post burst. Assuming the optical light curve continues the decline with the same power law index, we predict r' band magnitudes of 22.7 at 2 days and 23.4 at 4 days post burst. The broad band SED from g' to K can be fitted by a power law with index 0.8 +- 0.1 (statistical) +-0.1 (systematic), where the latter is due to the lack of photometric calibration.