Gamma-ray Burst 120229A

(All information courtesy of the instrument teams.)

Previous IAU Circulars

• none

• GCN/BACODINE POSITION NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Wed 29 Feb 12 14:35:36 UT
  NOTICE_TYPE:     Swift-BAT GRB Position
  TRIGGER_NUM:     516571,   Seg_Num: 0
  GRB_RA:           20.035d {+01h 20m 08s} (J2000),
                    20.174d {+01h 20m 42s} (current),
                    19.463d {+01h 17m 51s} (1950)
  GRB_DEC:         -35.807d {-35d 48' 26"} (J2000),
                   -35.744d {-35d 44' 37"} (current),
                   -36.070d {-36d 04' 09"} (1950)
  GRB_ERROR:       3.00 [arcmin radius, statistical only]
  GRB_INTEN:       1488 [cnts]    Image_Peak=144 [image_cnts]
  TRIGGER_DUR:     0.256 [sec] 
  TRIGGER_INDEX:   123     E_range: 25-100 keV
  BKG_INTEN:       27819 [cnts]
  BKG_TIME:        52496.05 SOD {14:34:56.05} UT
  BKG_DUR:         8 [sec]
  GRB_DATE:        15986 TJD;    60 DOY;   12/02/29
  GRB_TIME:        52511.16 SOD {14:35:11.16} UT
  GRB_PHI:         -150.25 [deg]
  GRB_THETA:        25.89 [deg]
  SOLN_STATUS:     0x3
  RATE_SIGNIF:     19.69 [sigma]
  IMAGE_SIGNIF:    9.66 [sigma]
  MERIT_PARAMS:     +1  +0  +0  -2  +2  +0 -100  +0 -71  +0 
  SUN_POSTN:       341.92d {+22h 47m 40s}   -7.66d {-07d 39' 45"}
  SUN_DIST:         44.80 [deg]   Sun_angle= -2.6 [hr] (East of Sun)
  MOON_POSTN:       63.46d {+04h 13m 50s}  +21.54d {+21d 32' 37"}
  MOON_DIST:        70.42 [deg]
  MOON_ILLUM:      46 [%]
  GAL_COORDS:      269.56,-79.39 [deg] galactic lon,lat of the burst (or transient)
  ECL_COORDS:        1.67,-40.34 [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:        This trigger occurred at longitude,latitude = 9.87,14.60 [deg]. 

• red DSS finding chart ps-file
  
  
• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Wed 29 Feb 12 14:40:36 UT
  NOTICE_TYPE:     Swift-BAT GRB Lightcurve
  TRIGGER_NUM:     9085451,   Seg_Num: 6
  GRB_RA:           20.035d {+01h 20m 08s} (J2000),
                    20.174d {+01h 20m 42s} (current),
                    19.463d {+01h 17m 51s} (1950)
  GRB_DEC:         -35.807d {-35d 48' 26"} (J2000),
                   -35.744d {-35d 44' 37"} (current),
                   -36.070d {-36d 04' 09"} (1950)
  GRB_DATE:        15986 TJD;    60 DOY;   12/02/29
  GRB_TIME:        52511.16 SOD {14:35:11.16} UT
  TRIGGER_INDEX:   123
  GRB_PHI:         -150.25 [deg]
  GRB_THETA:        25.89 [deg]
  DELTA_TIME:      -2690.00 [sec]
  TRIGGER_DUR:     0.256 [sec] 
  SOLN_STATUS:     0x3
  RATE_SIGNIF:     0.00 [sigma]
  IMAGE_SIGNIF:    0.00 [sigma]
  LC_URL:          sw00516571000msb.lc
  SUN_POSTN:       341.92d {+22h 47m 41s}   -7.66d {-07d 39' 40"}
  SUN_DIST:         44.80 [deg]   Sun_angle= -2.6 [hr] (East of Sun)
  MOON_POSTN:       63.50d {+04h 14m 01s}  +21.55d {+21d 32' 51"}
  MOON_DIST:        70.45 [deg]
  MOON_ILLUM:      46 [%]
  GAL_COORDS:      269.56,-79.39 [deg] galactic lon,lat of the burst (or transient)
  ECL_COORDS:        1.67,-40.34 [deg] ecliptic lon,lat of the burst (or transient)
  COMMENTS:        SWIFT-BAT GRB Lightcurve.  
  COMMENTS:           
  COMMENTS:        WARNING: No BAT_Position TDRSS message was received for this trigger_number!  
  COMMENTS:           
  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:        This trigger occurred at longitude,latitude = 9.87,14.60 [deg].
  COMMENTS:        The 3rd packet (of 3) was missing in the lightcurve data stream. 
  

  
• GCN Circular #12997
  V. Mangano (INAF-IASFPA), S. D. Barthelmy (GSFC), A. P. Beardmore (U Leicester), D. N. Burrows (PSU), S. Campana (INAF-OAB), J. R. Cummings (NASA/UMBC), V. D'Elia (ASDC), P. A. Evans (U Leicester), N. Gehrels (NASA/GSFC), B. Gendre (ASDC), C. Guidorzi (U Ferrara), S. T. Holland (STScI), J. A. Kennea (PSU), A. Y. Lien (NASA/GSFC/ORAU), O. M. Littlejohns (U Leicester), F. E. Marshall (NASA/GSFC), A. Maselli (INAF-IASFPA), A. Melandri (INAF-OAB), P. T. O\'Brien (U Leicester), K. L. Page (U Leicester), D. M. Palmer (LANL), P. Romano (INAF-IASFPA), B. Sbarufatti (INAF-OAB/PSU), C. A. Swenson (PSU), G. Tagliaferri (INAF-OAB) and B.-B. Zhang (PSU) report on behalf of the Swift Team:
  At 14:35:11 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 120229A (trigger=516571). Swift could not slew to the burst due to a sun constraint. The BAT on-board calculated location is RA, Dec 20.035, -35.807 which is

     RA(J2000) = 01h 20m 08s
     Dec(J2000) = -35d 48' 26"
  

  with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a single short peak structure with a duration of about 0.5 sec. The peak count rate was ~3000 counts/sec (15-350 keV), at ~0 sec after the trigger.
  Due to a Sun observing constraint, Swift cannot slew to the BAT position until 19:46 UT on 2012 April 17. There will thus be no XRT or UVOT data for this trigger before this time.
  We note that this location is 5 arc minutes from the relatively nearby (z=0.03) galaxy 6dFGSgJ012000.6-355307 .
  Burst Advocate for this burst is V. Mangano (vanessa AT ifc.inaf.it). 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 #12998
  C. B. Markwardt (GSFC), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), V. Mangano (INAF-IASFPA), D. M. Palmer (LANL), T. Sakamoto (GSFC/UMBC), G. Sato (ISAS), M. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (MSU) (i.e. the Swift-BAT team):
  Using the data set from T-60 to T+243 sec from the recent telemetry downlink, we report further analysis of BAT GRB 120229A (trigger #516571) (Mangano, et al., GCN Circ. 12997). The BAT ground-calculated position is RA, Dec = 20.033, -35.796 deg which is

      RA(J2000)  =  01h 20m 07.9s
      Dec(J2000) = -35d 47' 44.0"
  

  with an uncertainty of 1.9 arcmin, (radius, sys+stat, 90% containment). The partial coding was 85%.
  The mask-weighted light curve shows two peaks, the first about 0.08 seconds long peaking at T+0.03 and the second about 0.14 seconds long peaking at T+0.21 seconds. T90 (15-350 keV) is 0.22 +- 0.03 sec (estimated error including systematics).
  The time-averaged spectrum from T+0.01 to T+0.27 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.29 +- 0.24. The fluence in the 15-150 keV band is 4.1 +- 0.7 x 10^-08 erg/cm2. The 1-sec peak photon flux measured from T-0.36 sec in the 15-150 keV band is 0.5 +- 0.1 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/516571/BA/
• GCN Circular #12999
  J. Norris (BSU), S.D. Barthelmy (GSFC) for the BAT Team:
  We report the spectral lag analysis for GRB 120229A (GCN Circ. 12997) based on the BAT data. Using 4-ms binned light curves, the spectral lag for the 15-25 keV to 50-100 keV bands is 0.8 +-8 msec, and 3.6 +5/-7 msec for the 25-50 keV to 100-350 keV bands for both peaks combined. These lag values place this burst in the short burst category.
• GCN Report 368.1
  GCN_Report 368.1 has been posted: http://gcn.gsfc.nasa.gov/reports/report_368_1.pdf by V. Mangano at INAF IASF Pa titled: "Swift report om GRB 120229A"
• GCN Circular #13084
  W. Fong, E. Berger, N. Sanders (Harvard), K. Cooksey, A. Zangari (MIT) and N. Morrell (LCO) report:
  "We observed the location of the short-duration GRB 120229A (GCN 12997) with the Low Dispersion Survey Spectrograph 3 (LDSS3) mounted on the Magellan/Clay 6.5-meter telescope. We obtained 3x180-sec r-band observations on 2012 March 01.01 UT (9.6 hours post-burst) at high airmass in mediocre seeing conditions (1.3"). To check for the presence of a fading optical source, we re-observed the field (6x180-sec) on 2012 March 02.01 UT (33.6 hours post-burst and 24.0 hours after the first observations) at similar airmass. Digital image subtraction of the two epochs using the ISIS software package reveals no residuals within the BAT-refined position (GCN 12998). Therefore, calculating the zeropoint from a standard star field at similar airmass based on several stars, we place a 3-sigma limit of r>22.4 mag on the optical afterglow of GRB 120229A at 9.6 hours after the burst."