Gamma-ray Burst 140828A

(All information courtesy of the instrument teams.)

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Results of Observations

GCN/BACODINE POSITION NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Thu 28 Aug 14 06:58:00 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     610953,   Seg_Num: 0
GRB_RA:          142.011d {+09h 28m 03s} (J2000),
                 142.212d {+09h 28m 51s} (current),
                 141.325d {+09h 25m 18s} (1950)
GRB_DEC:         +14.590d {+14d 35' 24"} (J2000),
                 +14.526d {+14d 31' 32"} (current),
                 +14.808d {+14d 48' 30"} (1950)
GRB_DATE:        16897 TJD;   240 DOY;   14/08/28
GRB_TIME:        24854.04 SOD {06:54:14.04} UT
TRIGGER_INDEX:   148
GRB_PHI:         -60.14 [deg]
GRB_THETA:        38.07 [deg]
DELTA_TIME:      71.00 [sec]
TRIGGER_DUR:     1.024 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     15.84 [sigma]
IMAGE_SIGNIF:    7.41 [sigma]
LC_URL:          sw00610953000msb.lc
SUN_POSTN:       156.75d {+10h 27m 00s}   +9.71d {+09d 42' 37"}
SUN_DIST:         15.00 [deg]   Sun_angle= 1.0 [hr] (West of Sun)
MOON_POSTN:      183.78d {+12h 15m 07s}   -3.14d {-03d 08' 27"}
MOON_DIST:        44.81 [deg]
MOON_ILLUM:      7 [%]
GAL_COORDS:      217.08, 41.20 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      139.71, -0.33 [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:        This trigger occurred at longitude,latitude = 89.02,20.61 [deg].

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Thu 28 Aug 14 06:54:33 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     610953,   Seg_Num: 0
GRB_RA:          142.011d {+09h 28m 03s} (J2000),
                 142.212d {+09h 28m 51s} (current),
                 141.325d {+09h 25m 18s} (1950)
GRB_DEC:         +14.590d {+14d 35' 24"} (J2000),
                 +14.526d {+14d 31' 32"} (current),
                 +14.808d {+14d 48' 30"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       4267 [cnts]    Image_Peak=150 [image_cnts]
TRIGGER_DUR:     1.024 [sec] 
TRIGGER_INDEX:   148     E_range: 25-100 keV
BKG_INTEN:       26951 [cnts]
BKG_TIME:        24835.54 SOD {06:53:55.54} UT
BKG_DUR:         8 [sec]
GRB_DATE:        16897 TJD;   240 DOY;   14/08/28
GRB_TIME:        24854.04 SOD {06:54:14.04} UT
GRB_PHI:         -60.14 [deg]
GRB_THETA:        38.07 [deg]
SOLN_STATUS:     0x20000003
RATE_SIGNIF:     15.84 [sigma]
IMAGE_SIGNIF:    7.41 [sigma]
MERIT_PARAMS:     +1  +0  +0  +0  +2  -2 -100  +0 -96  +0 
SUN_POSTN:       156.75d {+10h 26m 59s}   +9.71d {+09d 42' 40"}
SUN_DIST:         15.00 [deg]   Sun_angle= 1.0 [hr] (West of Sun)
MOON_POSTN:      183.75d {+12h 15m 01s}   -3.13d {-03d 07' 54"}
MOON_DIST:        44.78 [deg]
MOON_ILLUM:      7 [%]
GAL_COORDS:      217.08, 41.20 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      139.71, -0.33 [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 = 89.02,20.61 [deg].  
COMMENTS:           
COMMENTS:        NOTE: This BAT event is temporally(2.0<100sec) coincident with the FERMI_GBM event (trignum=430901655).

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Thu 28 Aug 14 06:54:47 UT
NOTICE_TYPE:     Fermi-GBM Flight Position
RECORD_NUM:      57
TRIGGER_NUM:     430901655
GRB_RA:          141.467d {+09h 25m 52s} (J2000),
                 141.671d {+09h 26m 41s} (current),
                 140.770d {+09h 23m 05s} (1950)
GRB_DEC:         +17.700d {+17d 41' 60"} (J2000),
                 +17.636d {+17d 38' 10"} (current),
                 +17.917d {+17d 55' 00"} (1950)
GRB_ERROR:       15.97 [deg radius, statistical plus systematic]
GRB_INTEN:       116 [cnts/sec]
DATA_SIGNIF:     9.90 [sigma]
INTEG_TIME:      4.096 [sec]
GRB_DATE:        16897 TJD;   240 DOY;   14/08/28
GRB_TIME:        24852.18 SOD {06:54:12.18} UT
GRB_PHI:          17.00 [deg]
GRB_THETA:        60.00 [deg]
DATA_TIME_SCALE: 4.0960 [sec]
HARD_RATIO:      1.14
LOC_ALGORITHM:   3 (version number of)
MOST_LIKELY:      78%  GRB
2nd_MOST_LIKELY:  20%  Solar Flare
DETECTORS:       1,0,0, 1,0,0, 0,0,0, 0,0,0, 0,0,
SUN_POSTN:       156.75d {+10h 26m 59s}   +9.71d {+09d 42' 40"}
SUN_DIST:         16.64 [deg]   Sun_angle= 1.0 [hr] (West of Sun)
MOON_POSTN:      183.76d {+12h 15m 01s}   -3.13d {-03d 07' 56"}
MOON_DIST:        46.40 [deg]
MOON_ILLUM:      7 [%]
GAL_COORDS:      212.97, 41.89 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      138.24,  2.46 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2014/bn140828288/quicklook/glg_lc_medres34_bn140828288.gif
COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
COMMENTS:        This trigger occurred at longitude,latitude = 50.83,3.38 [deg].  
COMMENTS:        The LC_URL file will not be created until ~15 min after the trigger.  
COMMENTS:           
COMMENTS:        NOTE: This GBM event is temporally(2.0<100sec) coincident with the SWIFT_BAT event (trignum=610953).

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Thu 28 Aug 14 06:54:36 UT
NOTICE_TYPE:     Fermi-GBM Flight Position
RECORD_NUM:      45
TRIGGER_NUM:     430901655
GRB_RA:          162.050d {+10h 48m 12s} (J2000),
                 162.235d {+10h 48m 56s} (current),
                 161.418d {+10h 45m 40s} (1950)
GRB_DEC:          -5.917d {-05d 55' 00"} (J2000),
                  -5.994d {-05d 59' 39"} (current),
                  -5.652d {-05d 39' 07"} (1950)
GRB_ERROR:       33.25 [deg radius, statistical plus systematic]
GRB_INTEN:       58 [cnts/sec]
DATA_SIGNIF:     5.60 [sigma]
INTEG_TIME:      4.096 [sec]
GRB_DATE:        16897 TJD;   240 DOY;   14/08/28
GRB_TIME:        24852.18 SOD {06:54:12.18} UT
GRB_PHI:         351.00 [deg]
GRB_THETA:        35.00 [deg]
DATA_TIME_SCALE: 4.0960 [sec]
HARD_RATIO:      0.72
LOC_ALGORITHM:   3 (version number of)
MOST_LIKELY:      97%  GRB
2nd_MOST_LIKELY:   2%  Generic Transient
DETECTORS:       1,0,0, 1,0,0, 0,0,0, 0,0,0, 0,0,
SUN_POSTN:       156.75d {+10h 26m 59s}   +9.71d {+09d 42' 40"}
SUN_DIST:         16.63 [deg]   Sun_angle= -0.4 [hr] (East of Sun)
MOON_POSTN:      183.75d {+12h 15m 01s}   -3.13d {-03d 07' 55"}
MOON_DIST:        21.64 [deg]
MOON_ILLUM:      7 [%]
GAL_COORDS:      256.30, 45.51 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      165.75,-12.50 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2014/bn140828288/quicklook/glg_lc_medres34_bn140828288.gif
COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
COMMENTS:        This trigger occurred at longitude,latitude = 50.83,3.38 [deg].  
COMMENTS:        The LC_URL file will not be created until ~15 min after the trigger.  
COMMENTS:           
COMMENTS:        NOTE: This GBM event is temporally(2.0<100sec) coincident with the SWIFT_BAT event (trignum=610953).

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Thu 28 Aug 14 06:55:04 UT
NOTICE_TYPE:     Fermi-GBM Ground Position
RECORD_NUM:      56
TRIGGER_NUM:     430901655
GRB_RA:          138.300d {+09h 13m 12s} (J2000),
                 138.510d {+09h 14m 02s} (current),
                 137.583d {+09h 10m 20s} (1950)
GRB_DEC:         +22.100d {+22d 06' 00"} (J2000),
                 +22.039d {+22d 02' 20"} (current),
                 +22.307d {+22d 18' 24"} (1950)
GRB_ERROR:       6.46 [deg radius, statistical only]
DATA_SIGNIF:     12.10 [sigma]
DATA_INTERVAL:   4.096 [sec]
GRB_DATE:        16897 TJD;   240 DOY;   14/08/28
GRB_TIME:        24852.18 SOD {06:54:12.18} UT
GRB_PHI:          19.00 [deg]
GRB_THETA:        65.00 [deg]
E_RANGE:         44.032 - 279.965 [keV]
LOC_ALGORITHM:   4143 (Gnd S/W Version number)
SUN_POSTN:       156.75d {+10h 27m 00s}   +9.71d {+09d 42' 40"}
SUN_DIST:         21.40 [deg]   Sun_angle= 1.2 [hr] (West of Sun)
MOON_POSTN:      183.76d {+12h 15m 02s}   -3.13d {-03d 08' 00"}
MOON_DIST:        50.87 [deg]
MOON_ILLUM:      7 [%]
GAL_COORDS:      206.14, 40.52 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      134.05,  5.74 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2014/bn140828288/quicklook/glg_lc_medres34_bn140828288.gif
COMMENTS:        Fermi-GBM Ground-calculated Coordinates.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:        The LC_URL file will not be created until ~15 min after the trigger.  
COMMENTS:           
COMMENTS:        NOTE: This GBM event is temporally(2.0<100sec) coincident with the SWIFT_BAT event (trignum=610953).

GCN Circular #16751
A. Melandri (INAF-OAB), M. G. Bernardini (INAF-OAB), P. D'Avanzo (INAF-OAB), P. A. Evans (U Leicester), A. Y. Lien (GSFC/UMBC), K. L. Page (U Leicester), T. Sakamoto (AGU) and M. H. Siegel (PSU) report on behalf of the Swift Team:
At 06:54:14 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 140828A (trigger=610953). The BAT on-board calculated location is RA, Dec 142.011, +14.590 which is
```
   RA(J2000) = 09h 28m 03s
   Dec(J2000) = +14d 35' 24"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a single-peaked structure with a duration of about 20 sec. The peak count rate was ~1200 counts/sec (15-350 keV), at ~1 sec after the trigger.
Due to a Sun observing constraint, Swift cannot slew to the BAT position until 22:33 UT on 2014 September 29. There will thus be no XRT or UVOT data for this trigger before this time.
Burst Advocate for this burst is A. Melandri (andrea.melandri AT brera.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 #16754
A. von Kienlin (MPE) reports on behalf of the Fermi GBM Team:
"At 06:54:12.18 UT on 28 August 2014, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 140828A (trigger 430901655 / 140828288), which was also detected by the Swift/BAT (Melandri et al. 2014, GCN 16751) The GBM on-ground location is consistent with the Swift position.
The angle from the Fermi LAT boresight is 57 degrees.
The GBM light curve consists of a single pulse with a duration (T90) of about 24 s (50-300 keV). The time-averaged spectrum from T0-6.1 s to T0+16.4 s is best fit by a power law function with an exponential high-energy cutoff. The power law index is -1.5 +/- 0.1 and the cutoff energy, parameterized as Epeak, is 140 +/- 30 keV.
The event fluence (10-1000 keV) in this time interval is (3.5 +/- 0.2)E-06 erg/cm^2. The 1.024-sec peak photon flux measured starting from T0+2.43 s in the 10-1000 keV band is 3.5 +/- 0.2 ph/s/cm^2.
The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."
GCN Circular #16756
C. B. Markwardt (GSFC), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), A. Y. Lien (GSFC/UMBC), A. Melandri (INAF-OAB), D. M. Palmer (LANL), T. Sakamoto (AGU), M. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):
Using the data set from T-239 to T+963 sec from the recent telemetry downlink, we report further analysis of BAT GRB 140828A (trigger #610953) (Melandri, et al., GCN Circ. 16751). The BAT ground-calculated position is RA, Dec = 142.029, 14.569 deg which is
```
  RA(J2000)  =  09h 28m 07.0s 
  Dec(J2000) = +14d 34' 09.2" 
```
with an uncertainty of 1.3 arcmin, (radius, sys+stat, 90% containment). The partial coding was 26%.
The mask-weighted light curve shows a single peak starting at T-7 sec, peaking at T+1 sec and ending at T+10 sec. There is a hint of an emission peaking at T+14 sec. T90 (15-350 keV) is 18.8 +- 4.0 sec (estimated error including systematics).
The time-averaged spectrum from T-5.8 to T+18.4 sec is best fit by a power law with an exponential cutoff. This fit gives a photon index 0.6 +- 0.7, and Epeak of 54 +- 11 keV (chi squared 70.26 for 56 d.o.f.). For this model the total fluence in the 15-150 keV band is 1.3 +- 0.1 x 10^-6 erg/cm2 and the 1-sec peak flux measured from T+0.51 sec in the 15-150 keV band is 2.2 +- 0.3 ph/cm2/sec. A fit to a simple power law gives a photon index of 1.78 +- 0.13 (chi squared 81.57 for 57 d.o.f.). 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/610953/BA/

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Jochen Greiner, last update: 30-Aug-2014 [Disclaimer]