batgrbproduct Analysis for Trigger=280447
Analysis Summary
Notes:
- 1) No attempt has been made to eliminate the non-significant decimal places.
- 2) This batgrbproduct analysis is done of the amount of data for this trigger downloaded to date.
- 3) This page will be updated for up to 8 downlinks after the trigger.
======================================================================
BAT GRB EVENT DATA PROCESSING REPORT
Process Script Ver: batgrbproduct v2.41
Process Start Time (local time): Thu Dec 13 23:33:10 EST 2007
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger280447/GCN5_download_cron
======================================================================
Trigger: 00280447 Segment: 000
BAT Trigger Time: 201862160 [s; MET]
Trigger Stop: 201862224 [s; MET]
UTC: 2007-05-26T08:49:18.020040 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 301.271320885015 Dec: 31.4839180685745 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 8.39
Image Trigger?: YES
Rate S/N Ratio: 0 [ if not an image trigger ]
Image S/N Ratio: 8.39
Flight Position: [ source = BAT ]
RA: 301.271320885015 Dec: 31.4839180685745 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 301.290461683346 Dec: 31.435853372861 [deg; J2000]
{ 20h 05m 09.7s , +31d 26' 09.1" }
+/- 1.54274250642045 [arcmin] (estimated 90% radius based on SNR)
+/- 0.621027220270201 [arcmin] (formal 1-sigma fit error)
SNR: 16.3729804565335
RA = 20h 5m 9.7s (301.290462 deg.)
Dec = 31d 26' 9" (31.435853 deg.)
Angular difference between Flight and Ground position is 3.045727 arcmin
Partial Coding Fraction: 0.1953125 [ including projection effects ]
Duration
T90: 731.967999994755 +/- 117.785827624575
Measured from: 21.4160000085831
to: 753.384000003338 [s; relative to TRIGTIME]
T50: 166.976000010967 +/- 34.1638929925093
Measured from: 92.136000007391
to: 259.112000018358 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 153.620000004768
to: 154.620000004768 [s; relative to TRIGTIME]
Total Fluence
Measured from: 8.74399998784065
to: 869.99200001359 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 7.568546 8.891254 5.686708 1.574137
0.262760 0.265727 0.237410 0.209124 [error]
Peak 0.026467 0.044002 0.028766 0.036505
0.012414 0.012658 0.010626 0.009359 [error]
[ fluence units of on-axis counts / fully illuminated detector ]
======================================================================
=== Fluence/Peak Flux Summary ===
Model Band1 Band2 Band3 Band4 Band5 Total
15-25 25-50 50-100 100-350 15-150 15-350 keV
Fluence Power-law 3.16e-06 4.48e-06 4.72e-06 9.16e-06 1.52e-05 2.15e-05 erg/cm2
Error 2.24e-07 1.83e-07 2.48e-07 1.06e-06 5.94e-07 1.23e-06 erg/cm2
Peak flux Power-law 2.82e-01 3.30e-01 2.77e-01 3.93e-01 1.03e+00 1.28e+00 ph/cm2/s
Error 1.86e-01 1.36e-01 8.73e-02 2.69e-01 3.61e-01 3.88e-01 ph/cm2/s
Fluence Cutoff-PL 2.97e-06 4.58e-06 4.81e-06 6.28e-06 1.49e-05 1.86e-05 erg/cm2
Error 2.91e-07 2.09e-07 2.71e-07 2.44e-06 6.71e-07 2.63e-06 erg/cm2
Peak flux Cutoff-PL 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 ph/cm2/s
Error 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 ph/cm2/s
Fluence Band 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 erg/cm2
Error 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 erg/cm2
Peak flux Band 2.31e-01 3.68e-01 1.23e+00 0.00e+00 0.00e+00 0.00e+00 ph/cm2/s
Error 4.21e-01 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.927 0.074 - - 2.43e-03 9.58e-05 47.114 57
CPL 1.596 0.000 63.3 4974.7 3.51e-03 1.19e-03 44.543 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.252 0.558 - - 8.70e-03 2.78e-03 51.770 57
CPL 1.108 0.000 357.3 0.0 1.01e-02 0.00e+00 51.751 56
Model : spectral model: simple power-law (PL) and cutoff power-law (CPL)
Ph_index : photon index: E^-{Ph_index} (minus sign is not included in the index)
Ph_90err : 90% error of the photon index
Epeak : Epeak in keV
Epeak_90err: 90% error of Epeak
Norm : normalization at 50 keV in PL model and at 1 keV in CPL model
Nomr_90err : 90% error of the normalization
chi2 : Chi-Squared
dof : degree of freedom
=== T90/T50 calculation in the 50-300 keV band (BATSE band) using 64 ms lc ===
T90 in the 50-300 keV band: 0.064000 sec.
T50 in the 50-300 keV band: 0.064000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 861.248 8.744 869.992
T90 731.968 21.416 753.384
T50 166.976 92.136 259.112
Peak 1.000 153.620 154.620
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
301.2905 +31.4359 0.0117 49.7 -29.2 15.6508 16.4 TRIG_00280447
------------------------------------------
Foreground time interval of the image:
8.744 165.780 (delta_t = 157.036 [sec])
167.000 303.077 (delta_t = 136.077 [sec])
481.000 554.540 (delta_t = 73.540 [sec])
556.000 602.501 (delta_t = 46.501 [sec])
Background time interval of the image:
-119.000 8.744 (delta_t = 127.744 [sec])
Lightcurves
Notes:
- 1) All plots contain as much data as has been downloaded to date.
- 2) Multiple plots of different time binning/intervals are shown to cover all scenarios of short/long GRBs, rate/image triggers, and real/false positives.
- 3) For all the mask-weighted lightcurves, the y-axis units are counts/sec/det where a det is 0.4 x 0.4 = 0.16 sq cm.
- 4) The verticle lines correspond to following: green dotted lines are T50 interval, black dotted lines are T90 interval, blue solid line(s) is a spacecraft slew start time, and orange solid line(s) is a spacecraft slew end time.
- 5) Time of each bin is in the middle of the bin.
1 s binning
From T0-310 s to T0+310 s
From T100_start - 20 s to T100_end + 30 s
Full time interval
64 ms binning
Full time interval
From T100_start to T100_end
From T0-5 sec to T0+5 sec
16 ms binning
From T100_start-5 s to T100_start+5 s
8 ms binning
From T100_start-3 s to T100_start+3 s
2 ms binning
From T100_start-1 s to T100_start+1 s
SN=5 or 10 sec. binning (whichever binning is satisfied first)
SN=5 or 10 sec. binning (T < 200 sec)
Spectra
Notes:
- 1) The fitting includes the systematic errors.
- 2) For long bursts, a spectral fit of the pre-slew DRM will introduce some errors in both a spectral shape and a normalization if the PHA file contains a lot of the slew/post-slew time interval.
- 3) For fits to more complicated models (e.g. a power-law over a cutoff power-law), the BAT team has decided to require a chi-square improvement of more than 6 for each extra dof.
Time averaged spectrum fit using the pre-slew DRM
Power-law model
Multiple GTIs in the spectrum
tstart tstop
8.744000 165.780000
167.000000 303.077400
481.000000 554.540000
556.000000 869.992000
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.92662 ( -7.386160E-02 7.469153E-02) )
Norm@50keV : 2.434234E-03 ( -9.603263E-05 9.559351E-05) )
------------------------------------------------------------
Chi-Squared = 47.11427 using 59 PHA bins.
Reduced chi-squared = 0.8265660 for 57 degrees of freedom
Null hypothesis probability = 0.822
Photon flux (15-150 keV) in 680.6 sec: 0.353355 ( -0.015405 0.015503 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.52375e-05 ( -5.93687e-07 5.94164e-07 ) ergs/cm2
Cutoff power-law model
Multiple GTIs in the spectrum
tstart tstop
8.744000 165.780000
167.000000 303.077400
481.000000 554.540000
556.000000 869.992000
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.59573 ( )
Epeak [keV] : 63.3161 ( -14.2755 9935.09 )
Norm@50keV : 3.512019E-03 ( -9.092237E-04 1.477022E-03) )
------------------------------------------------------------
Chi-Squared = 44.54251 using 59 PHA bins.
Reduced chi-squared = 0.7954020 for 56 degrees of freedom
Null hypothesis probability = 0.865
Photon flux (15-150 keV) in 680.6 sec: 0.345216 ( -0.01735 0.017513 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.49486e-05 ( -6.75359e-07 6.66784e-07 ) ergs/cm2
Band function
Multiple GTIs in the spectrum
tstart tstop
8.744000 165.780000
167.000000 303.077400
481.000000 554.540000
556.000000 869.992000
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.34902 ( -0.501685 0.753099 )
beta : -2.09631 ( -7.90707 0.169755 )
Epeak [keV] : 49.9648 ( -17.0044 151.911 )
Norm@50keV : 4.919010E-03 ( -2.007065E-03 9.093417E-03) )
------------------------------------------------------------
Chi-Squared = 43.98762 using 59 PHA bins.
Reduced chi-squared = 0.7997749 for 55 degrees of freedom
Null hypothesis probability = 0.857
Photon flux (15-150 keV) in 680.6 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 153.640 sec. to 154.600 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.25182 ( -0.596464 0.519783 )
Norm@50keV : 8.702290E-03 ( -2.837171E-03 2.730636E-03) )
------------------------------------------------------------
Chi-Squared = 51.76963 using 59 PHA bins.
Reduced chi-squared = 0.9082391 for 57 degrees of freedom
Null hypothesis probability = 0.671
Photon flux (15-150 keV) in 0.9600 sec: 1.02959 ( -0.35617 0.36583 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.3556e-08 ( -2.55403e-08 2.56066e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 153.640 sec. to 154.600 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.10815 ( )
Epeak [keV] : 357.314 ( )
Norm@50keV : 1.011857E-02 ( )
------------------------------------------------------------
Chi-Squared = 51.75111 using 59 PHA bins.
Reduced chi-squared = 0.9241269 for 56 degrees of freedom
Null hypothesis probability = 0.636
Photon flux (15-150 keV) in 0.9600 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Band function
Time interval is from 153.640 sec. to 154.600 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.438558 ( -11.0014 3.99856 )
beta : -1.35074 ( -8.52700 0.744312 )
Epeak [keV] : 74.3529 ( -39.3964 668.575 )
Norm@50keV : 2.591133E-02 ( -54.6257 25.5166 )
------------------------------------------------------------
Chi-Squared = 51.45530 using 59 PHA bins.
Reduced chi-squared = 0.9355510 for 55 degrees of freedom
Null hypothesis probability = 0.611
Photon flux (15-150 keV) in 0.9600 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Plot creation:
Thu Dec 13 23:51:56 EST 2007