Gamma-ray Burst 080218

(All information courtesy of the instrument teams.)

Previous IAU Circulars

• none

• GCN/BACODINE POSITION NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Mon 18 Feb 08 20:09:21 UT
  NOTICE_TYPE:     Swift-BAT GRB Position
  TRIGGER_NUM:     303609,   Seg_Num: 0
  GRB_RA:          355.922d {+23h 43m 41s} (J2000),
                   356.025d {+23h 44m 06s} (current),
                   355.286d {+23h 41m 09s} (1950)
  GRB_DEC:         +12.175d {+12d 10' 29"} (J2000),
                   +12.220d {+12d 13' 12"} (current),
                   +11.897d {+11d 53' 50"} (1950)
  GRB_ERROR:       3.00 [arcmin radius, statistical only]
  GRB_INTEN:       15663 [cnts]    Image_Peak=224 [image_cnts]
  TRIGGER_DUR:     4.096 [sec] 
  TRIGGER_INDEX:   291     E_range: 15-50 keV
  BKG_INTEN:       143465 [cnts]
  BKG_TIME:        72469.41 SOD {20:07:49.41} UT
  BKG_DUR:         40 [sec]
  GRB_DATE:        14514 TJD;    49 DOY;   08/02/18
  GRB_TIME:        72522.79 SOD {20:08:42.79} UT
  GRB_PHI:         -36.12 [deg]
  GRB_THETA:        47.40 [deg]
  SOLN_STATUS:     0x83
  RATE_SIGNIF:     9.84 [sigma]
  IMAGE_SIGNIF:    6.62 [sigma]
  MERIT_PARAMS:     +1  +0  +0  +2  +1  +0 -100  +0 -83  +1 
  SUN_POSTN:       331.65d {+22h 06m 37s}  -11.63d {-11d 37' 51"}
  SUN_DIST:         33.97 [deg]   Sun_angle= -1.6 [hr] (East of Sun)
  MOON_POSTN:      123.53d {+08h 14m 07s}  +22.24d {+22d 14' 19"}
  MOON_DIST:       118.08 [deg]
  MOON_ILLUM:      94 [%]
  GAL_COORDS:       98.05,-47.40 [deg] galactic lon,lat of the burst (or transient)
  ECL_COORDS:        1.18, 12.78 [deg] ecliptic lon,lat of the burst (or transient)
  COMMENTS:        SWIFT-BAT GRB Coordinates.  
  COMMENTS:        This is a rate trigger.  
  COMMENTS:        A point_source was found.  
  COMMENTS:        This does not match any source in the on-board catalog.  
  COMMENTS:        This does not match any source in the ground catalog.  
  COMMENTS:        This is a GRB.  
  COMMENTS:        Since the IMAGE_SIGNIF is less than 7 sigma, this is a questionable detection.  
  COMMENTS:        This trigger occurred at longitude,latitude = 278.21,20.27 [deg].  
  

• red DSS finding chart ps-file
  
  
• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Mon 18 Feb 08 20:12:18 UT
  NOTICE_TYPE:     Swift-BAT GRB Lightcurve
  TRIGGER_NUM:     303609,   Seg_Num: 0
  GRB_RA:          355.922d {+23h 43m 41s} (J2000),
                   356.025d {+23h 44m 06s} (current),
                   355.286d {+23h 41m 09s} (1950)
  GRB_DEC:         +12.175d {+12d 10' 29"} (J2000),
                   +12.220d {+12d 13' 12"} (current),
                   +11.897d {+11d 53' 50"} (1950)
  GRB_DATE:        14514 TJD;    49 DOY;   08/02/18
  GRB_TIME:        72522.79 SOD {20:08:42.79} UT
  TRIGGER_INDEX:   291
  GRB_PHI:         -36.12 [deg]
  GRB_THETA:        47.40 [deg]
  DELTA_TIME:      -57.00 [sec]
  TRIGGER_DUR:     4.096 [sec] 
  SOLN_STATUS:     0x83
  RATE_SIGNIF:     9.84 [sigma]
  IMAGE_SIGNIF:    6.62 [sigma]
  LC_URL:          sw00303609000msb.lc
  SUN_POSTN:       331.66d {+22h 06m 37s}  -11.63d {-11d 37' 48"}
  SUN_DIST:         33.97 [deg]   Sun_angle= -1.6 [hr] (East of Sun)
  MOON_POSTN:      123.56d {+08h 14m 14s}  +22.23d {+22d 13' 48"}
  MOON_DIST:       118.11 [deg]
  MOON_ILLUM:      94 [%]
  GAL_COORDS:       98.05,-47.40 [deg] galactic lon,lat of the burst (or transient)
  ECL_COORDS:        1.18, 12.78 [deg] ecliptic lon,lat of the burst (or transient)
  COMMENTS:        SWIFT-BAT GRB Lightcurve.  
  COMMENTS:           
  COMMENTS:        The next comments were copied from the BAT_POS Notice:  
  COMMENTS:        This is a rate trigger.  
  COMMENTS:        A point_source was found.  
  COMMENTS:        This does not match any source in the on-board catalog.  
  COMMENTS:        This does not match any source in the ground catalog.  
  COMMENTS:        This is a GRB.  
  COMMENTS:        Since the IMAGE_SIGNIF is less than 7 sigma, this is a questionable detection.  
  COMMENTS:        This trigger occurred at longitude,latitude = 278.21,20.27 [deg].  
  

  
• GCN Circular #7313
  H. Ziaeepour (UCL-MSSL), S. D. Barthelmy (GSFC), J. R. Cummings (NASA/UMBC), P. A. Evans (U Leicester), S. T. Holland (CRESST/USRA/GSFC), J. A. Kennea (PSU), W. B. Landsman (NASA/GSFC), K. M. McLean (GSFC/UMD), C. Pagani (PSU), D. M. Palmer (LANL), T. Sakamoto (NASA/UMBC), G. Sato (GSFC/ISAS), M. Stamatikos (NASA/ORAU), D. E. Vanden Berk (PSU), L. Vetere (PSU) and P. A. Ward (MSSL-UCL) report on behalf of the Swift Team:
  At 20:08:42 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 080218 (trigger=303609). Swift did not slew to the burst location because of the Sun observing constraint (34 deg from the Sun). The BAT on-board calculated location is RA, Dec 355.922, +12.175 which is

     RA(J2000)  =  23h 43m 41s
     Dec(J2000) = +12d 10' 29"
  

  with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve shows a weak peak around T_0. The peak count rate was ~400 counts/sec (15-350 keV).
  Because this burst is in the Sun constraint until May, no XRT or UVOT data will be available.
  Burst Advocate for this burst is H. Ziaeepour (hz AT mssl.ucl.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 Circular #7317
  E. Fenimore (LANL), S. D. Barthelmy (GSFC), J. Cummings (GSFC/UMBC), N. Gehrels (GSFC), H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD), K. McLean (GSFC/UMD), D. Palmer (LANL), A. Parsons (GSFC), T. Sakamoto (GSFC/UMBC), G. Sato (GSFC/ISAS), M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC), T. Ukwatta (GWU), H. Ziaeepour (UCL-MSSL) (i.e. the Swift-BAT team):
  Using the data set from T-239 to T+303 sec from the recent telemetry downlink, we report further analysis of BAT GRB 080218A (trigger #303609) (Ziaeepour, et al., GCN Circ. 7313). The BAT ground-calculated position is RA, Dec = 355.941, 12.159 deg which is

     RA(J2000)  = 23h 43m 45.8s 
     Dec(J2000) = 12d 9' 34" 
  

  with an uncertainty of 2.5 arcmin, (radius, sys+stat, 90% containment). The partial coding was 21%.
  The mask-weighted light curve shows three peaks at T-12 sec, T+0 sec, and T+9 sec. T90 (15-350 keV) is 27.6 +- 5.9 sec (estimated error including systematics).
  The time-averaged spectrum from T-12.8 to T+18.6 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 2.34 +- 0.35. The fluence in the 15-150 keV band is 6.3 +- 1.4 x 10^-07 erg/cm2. The 1-sec peak photon flux measured from T+1.22 sec in the 15-150 keV band is 1.4 +- 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/303609/BA/
• GCN Report 116.1
  GCN_Report 116.1 has been posted: http://gcn.gsfc.nasa.gov/reports/report_116_1.pdf by H. Ziaeepour at UCL/MSSL titled: "Final Swift observations of GRB 080218A"