GRB180204A

This page lists all entries on GRB180204A in GRBweb

Summary Fermi GBM IPN Swift GCN 22375 GCN 22376 GCN 22377 GCN 22378 GCN 22379 GCN 22380 GCN 22385 GCN 22399 GCN 22422

Summary table
Variable Value Source
GRB_name_Fermi GRB180204109
T0 2:36:12.902 UTC GCN_circulars,Konus-Wind Det
ra 330.1332° Swift
decl 30.8378° Swift
pos_error 1.81e-04° Swift
T90 1.152 s Fermi_GBM
T90_error 0.091 s Fermi_GBM
T90_start 2:36:16.862 UTC Fermi_GBM
fluence 1.75e-06 erg/cm² Fermi_GBM
fluence_error 1.26e-08 erg/cm² Fermi_GBM
T100 5.112 s
GBM_located False
mjd 58153.108482662035 GCN_circulars,Konus-Wind Det
Fermi GBM table
GRB_name_Fermi GRB180204109
trigger_name bn180204109
ra 330.1342°
decl 30.8381°
pos_error 4.33e+00°
datum 2018-02-04
t_trigger 2:36:16.926 UTC
T90 1.152 s
T90_error 0.091 s
T90_start 2:36:16.862 UTC
fluence 1.75e-06 erg/cm²
fluence_error 1.26e-08 erg/cm²
flux_1024 7.55e+00 erg/cm²/s
flux_1024_error 2.80e-01 erg/cm²/s
flux_1024_time 0.00e+00 erg/cm²/s
flux_64 1.97e+01 erg/cm²/s
flux_64_error 1.57e+00 erg/cm²/s
IPN table
GRB_name GRB180204A
ra 330.1167°
decl 30.8500°
pos_error 5.00e-02°
Swift table
GRB_name GRB180204A
t_trigger 2:36:16 UTC
ra 330.1332°
decl 30.8378°
pos_error 1.81e-04°
T90 1.16 s
fluence 4.80e-07 erg/cm²
GCN 22375 table
GRB_name GRB180204A
GCN_number 22375
Detection_method Swift Det
t_trigger 2:36:16 UTC
ra 330.1180°
decl 30.8460°
Circular_text TITLE: GCN CIRCULAR NUMBER: 22375 SUBJECT: GRB 180204A: Swift detection of a short burst DATE: 18/02/04 02:58:47 GMT FROM: David Palmer at LANL K. L. Page (U Leicester), A. P. Beardmore (U Leicester), A. Deich (PSU), J. A. Kennea (PSU), N. P. M. Kuin (UCL-MSSL), A. Y. Lien (GSFC/UMBC), F. E. Marshall (NASA/GSFC), D. M. Palmer (LANL), A. Tohuvavohu (PSU) and T. N. Ukwatta (LANL) report on behalf of the Neil Gehrels Swift Observatory Team: At 02:36:16 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 180204A (trigger=808483). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 330.118, +30.846 which is RA(J2000) = 22h 00m 28s Dec(J2000) = +30d 50' 45" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a double-peaked structure with a duration of about 1.5 sec. The peak count rate was ~17000 counts/sec (15-350 keV), at ~0 sec after the trigger. The XRT began observing the field at 02:37:43.8 UT, 87.2 seconds after the BAT trigger. Using promptly downlinked data we find an uncatalogued X-ray source located at RA, Dec 330.13359, 30.83807 which is equivalent to: RA(J2000) = 22h 00m 32.06s Dec(J2000) = +30d 50' 17.1" with an uncertainty of 3.8 arcseconds (radius, 90% containment). This location is 56 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. We cannot determine whether the source is fading at the present time. No spectrum from the promptly downlinked event data is yet available to determine the column density. UVOT took a finding chart exposure of 150 seconds with the White filter starting 92 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 0.10. Burst Advocate for this burst is K. L. Page (klp5 AT leicester.ac.uk). 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 22376 table
GRB_name GRB180204A
GCN_number 22376
Detection_method Swift-XRT Other
ra 330.1333°
decl 30.8381°
Circular_text TITLE: GCN CIRCULAR NUMBER: 22376 SUBJECT: GRB 180204A: Swift-XRT refined Analysis DATE: 18/02/04 10:26:23 GMT FROM: Phil Evans at U of Leicester J.P. Osborne (U. Leicester), A.P. Beardmore (U. Leicester), A. Melandri (INAF-OAB), P. D'Avanzo (INAF-OAB), V. D'Elia (ASDC), D.N. Burrows (PSU), A. Tohuvavohu (PSU), S. J. LaPorte (PSU) and K.L. Page report on behalf of the Swift-XRT team: We have analysed 8.0 ks of XRT data for GRB 180204A (Page et al. GCN Circ. 22375), from 90 s to 21.2 ks after the BAT trigger. The data comprise 32 s in Windowed Timing (WT) mode with the remainder in Photon Counting (PC) mode. The best available XRT position (using the promptly downlinked event data, the XRT-UVOT alignment and matching UVOT field sources to the USNO-B1 catalogue) is RA, Dec = 330.1333, 30.8381 which is equivalent to: RA (J2000): 22 00 32.00 Dec(J2000): +30 50 17.1 with an uncertainty of 2.1 arcsec (radius, 90% confidence). The light curve can be modelled with a power-law decay with a decay index of alpha=1.15 (+/-0.03). A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 2.02 (+0.23, -0.22). The best-fitting absorption column is 6.9 (+1.7, -1.5) x 10^21 cm^-2, in excess of the Galactic value of 1.0 x 10^21 cm^-2 (Willingale et al. 2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 4.3 x 10^-11 (7.6 x 10^-11) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Total column: 6.9 (+1.7, -1.5) x 10^21 cm^-2 Galactic foreground: 1.0 x 10^21 cm^-2 Excess significance: 6.5 sigma Photon index: 2.02 (+0.23, -0.22) If the light curve continues to decay with a power-law decay index of 1.15, the count rate at T+24 hours will be 2.7 x 10^-3 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.2 x 10^-13 (2.0 x 10^-13) erg cm^-2 s^-1. The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00808483. This circular is an official product of the Swift-XRT team.
GCN 22377 table
GRB_name GRB180204A
GCN_number 22377
Detection_method Swift-XRT Det
ra 330.1333°
decl 30.8378°
Circular_text TITLE: GCN CIRCULAR NUMBER: 22377 SUBJECT: GRB 180204A: Enhanced Swift-XRT position DATE: 18/02/04 10:47:55 GMT FROM: Phil Evans at U of Leicester J.P. Osborne, A.P. Beardmore, P.A. Evans and M.R. Goad (U. Leicester) report on behalf of the Swift-XRT team. Using 6274 s of XRT Photon Counting mode data and 9 UVOT images for GRB 180204A, 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 = 330.13329, +30.83785 which is equivalent to: RA (J2000): 22h 00m 31.99s Dec (J2000): +30d 50' 16.2" with an uncertainty of 1.4 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.
GCN 22378 table
GRB_name GRB180204A
GCN_number 22378
Detection_method Fermi GBM Det
t_trigger 2:36:16.930 UTC
Circular_text TITLE: GCN CIRCULAR NUMBER: 22378 SUBJECT: GRB 180204A: Fermi GBM detection DATE: 18/02/04 14:24:46 GMT FROM: Adam Goldstein at Fermi-GBM/UAH P. Veres and C. Meegan (both UAH) report on behalf of the Fermi GBM Team: "At 02:36:16.93 UT on 04 February 2018, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 180204A (trigger 539404581 / 180204109) which was also detected by the Swift/BAT (Page et al., GCN 22375). The GBM on-ground location is consistent with the Swift position. The angle from the Fermi LAT boresight at the GBM trigger time is 68 degrees. The GBM light curve shows two peaks with a duration (T90) of about 1.2 s (50-300 keV). The time-averaged spectrum from T0-0.1 s to T0+1.2 s is best fit by a power law function with an exponential high-energy cutoff. The power law index is -0.92 +/- 0.07 and the cutoff energy, parameterized as Epeak, is 781 +/- 161 keV. The event fluence (10-1000 keV) in this time interval is (8.48 +/- 0.32)E-7 erg/cm^2. The 64-msec peak photon flux measured starting from T0 in the 10-1000 keV band is 19.7 +/- 1.6 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."
GCN 22379 table
GRB_name GRB180204A
GCN_number 22379
Detection_method Swift-UVOT Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 22379 SUBJECT: GRB 180204A: Swift/UVOT Upper Limits DATE: 18/02/04 16:50:12 GMT FROM: Paul Kuin at MSSL N. P. M. Kuin (UCL-MSSL) and K. L. Page (U. Leicester) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 180204A 92 s after the BAT trigger (Page et al., GCN Circ. 22375). A star is present in the GSC whos position is consistent with the enhanced XRT position (Osborne et al. GCN Circ. 22377). No optical afterglow above the stellar flux has been detected in the initial UVOT exposures. Preliminary 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first finding chart (FC) exposure and subsequent exposures are: Filter T_start(s) T_stop(s) Exp(s) Mag white_FC 92 242 147 >20.3 u_FC 304 554 246 >19.9 white 92 17884 1210 >20.8 v 633 10587 1107 >19.0 b 560 23622 1840 >20.7 u 304 23062 2409 >21.1 w1 3943 22148 1917 >21.0 m2 658 11492 1095 >20.8 w2 609 6398 413 >20.1 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.10 in the direction of the burst (Schlegel et al. 1998).
GCN 22380 table
GRB_name GRB180204A
GCN_number 22380
Detection_method Swift-BAT Det
ra 330.1230°
decl 30.8520°
Circular_text TITLE: GCN CIRCULAR NUMBER: 22380 SUBJECT: GRB 180204A: Swift-BAT refined analysis DATE: 18/02/04 22:02:03 GMT FROM: Amy Lien at GSFC J. R. Cummings (CPI), S. D. Barthelmy (GSFC), H. A. Krimm (NSF/USRA), A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), J. P. Norris (BSU), K. L. Page (U Leicester), D. M. Palmer (LANL), T. Sakamoto (AGU), M. Stamatikos (OSU), T. N. Ukwatta (LANL) (i.e. the Swift-BAT team): Using the data set from T-186 to T+963 sec from the recent telemetry downlink, we report further analysis of BAT GRB 180204A (trigger #808483) (Page et al., GCN Circ. 22375). The BAT ground-calculated position is RA, Dec = 330.123, 30.852 deg which is RA(J2000) = 22h 00m 29.5s Dec(J2000) = +30d 51' 07.5" with an uncertainty of 1.1 arcmin, (radius, sys+stat, 90% containment). The partial coding was 70%. The mask-weighted light curve shows two distict pulses. The first pulse starts and peaks at ~T0, and ends at ~T+0.2. The second pulse starts at ~T+0.6 s, peaks at ~T+1 s, and ends at ~T+1.3 s. T90 (15-350 keV) is 1.16 +- 0.12 sec (estimated error including systematics). For the first pulse, the lag analysis finds a lag of -0.2 +- 1 ms for the 100-350 keV to 25-100 keV, and 0.2 +- 1.5 ms for the 50-100 keV to 15-25 keV band. The second pulse has a lag of 5.6 +- 3.9 ms for the 100-350 keV to 25-100 keV, and 3.2 +- 6.6 ms for the 50-100 keV to 15-25 keV band. These values are consistent with those of a short GRB. The time-averaged spectrum from T-0.05 to T+1.29 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.09 +- 0.10. The fluence in the 15-150 keV band is 4.8 +- 0.3 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T-0.05 sec in the 15-150 keV band is 3.6 +- 0.3 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/808483/BA/
GCN 22385 table
GRB_name GRB180204A
GCN_number 22385
Detection_method Konus-Wind Det
t_trigger 2:36:12.902 UTC
Circular_text TITLE: GCN CIRCULAR NUMBER: 22385 SUBJECT: Konus-Wind observation of GRB 180204A DATE: 18/02/05 12:16:14 GMT FROM: Anna Kozlova at Ioffe Institute A. Kozlova, S. Golenetskii, R. Aptekar, D. Frederiks, P. Oleynik, M. Ulanov, D. Svinkin, A. Tsvetkova, A. Lysenko, and T. Cline on behalf of the Konus-Wind team, report: The short-duration GRB 180204A (Swift-BAT detection and analysis: Page et al., GCN 22375; Cummings et al., GCN 22380; Fermi-GBM observation: Veres&Meegan, GCN 22378) triggered Konus-Wind at T0=9372.902 s UT (02:36:12.902). The burst light curve shows two peaks in the interval from ~T0-0.1 s to ~T0+1.1 s. The emission is seen up to ~10 MeV. As observed by Konus-Wind, the burst had a fluence of 3.81(-0.57,+0.66)x10^-6 erg/cm2, and a 16-ms peak flux, measured from T0+0.038 s, of 2.95(-0.80,+0.87)x10^-5 erg/cm2/s (both in the 20 keV - 10 MeV energy range). The spectrum of the burst (measured from T0 to T0+0.256 s) is best fit in the 20 keV - 10 MeV range by a power law with exponential cutoff model: dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep) with alpha = -0.36(-0.29,+0.38) and Ep = 843(-177,+263) keV (chi2 = 37/45 dof). Fitting by a GRB (Band) model yields the same alpha and Ep, and an upper limit on the high energy photon index: beta < -2.5 (chi2 = 37/44 dof) The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB180204_T09372/ All the quoted errors are at the 90% confidence level. All the quoted values are preliminary.
GCN 22399 table
GRB_name GRB180204A
GCN_number 22399
Detection_method MITSuME
Circular_text TITLE: GCN CIRCULAR NUMBER: 22399 SUBJECT: GRB 180204A: MITSuME Okayama optical upper limits DATE: 18/02/07 08:04:10 GMT FROM: Kotaro Morita at Tokyo Tech K. Morita, R. Itoh, K. L. Murata, T. Yoshii, Y. Tachibana, S. Harita, T. Ozawa, H. Mamiya, K. Shiraishi, Y. Yatsu, and N. Kawai (Tokyo Tech) report on behalf of the MITSuME collaboration: We searched for the optical counterpart of GRB 180204A (K. L. Page et al., GCN Circular #22375) with the optical three color (g', Rc, and Ic) CCD cameras attached to the MITSuME 50 cm telescope of Okayama Astrophysical Observatory, Japan. The observation started on 2018-02-04 9:37:11.83 UT. We did not find any new point source within the XRT circle (J. P. Osborne et al., GCN Circular #22377) in all three bands. We obtained following limits for the magnitudes. T0+[h] MID-UT T-EXP[sec] g' Rc Ic ------------------------------------------------------------ ------------------------------------------- ~7.0 9:48:54 1140 >17.5 >17.4 >17.0 ------------------------------------------------------------ ------------------------------------------- T0+ : Elapsed time after the burst T-EXP: Total Exposure time We used GSC2.3 catalog for flux calibration
GCN 22422 table
GRB_name GRB180204A
GCN_number 22422
Detection_method Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 22422 SUBJECT: GRB 180204A: 15 GHz upper limits from AMI DATE: 18/02/19 11:31:28 GMT FROM: Joe Bright at U of Oxford J. Bright, R. Fender (Oxford), and K. P. Mooley (NRAO, Caltech; Jansky Fellow) We have initiated the AMI short-GRB program. We observed the field of GRB 180204A (Page et al., GCN 22375) with the AMI Large Array at 15.5 GHz. Our observations on 2018 Feb 04.54, Feb 05.55, Feb 06.62 and Feb 09-11 (0.43 d, 1.44 d, 2.51 d and 5-7 d coadd post-burst) do not reveal any radio source at the XRT location (Osborne et al., GCN 22377), with 3sigma upper limits of 55 uJy, 54 uJy, 76 uJy and 63 uJy respectively. Results from the AMI short-GRB program will be posted on the AMI-GRB database available at http://4pisky.org/ami-grb/ . We thank the MRAO staff for scheduling these observations.