batgrbproduct Analysis for Trigger=276321
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 18:34:10 EST 2007
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger276321/GCN5_download_cron
======================================================================
Trigger: 00276321 Segment: 000
BAT Trigger Time: 198742695.424 [s; MET]
Trigger Stop: 198742697.472 [s; MET]
UTC: 2007-04-20T06:18:13.522060 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 121.252999205293 Dec: -45.5608340567608 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 10.94
Image Trigger?: NO
Rate S/N Ratio: 23.9374184071716 [ if not an image trigger ]
Image S/N Ratio: 10.94
Flight Position: [ source = BAT ]
RA: 121.252999205293 Dec: -45.5608340567608 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 121.245746121695 Dec: -45.5632127683013 [deg; J2000]
{ 08h 04m 59.0s , -45d 33' 47.6" }
+/- 0.975760764474733 [arcmin] (estimated 90% radius based on SNR)
+/- 0.397771094181992 [arcmin] (formal 1-sigma fit error)
SNR: 31.5022928303515
RA = 8h 4m 59.0s (121.245746 deg.)
Dec = -45d 33' 48" (-45.563213 deg.)
Angular difference between Flight and Ground position is 0.336460 arcmin
Partial Coding Fraction: 0.08398438 [ including projection effects ]
Duration
T90: 74.3480000197887 +/- 5.60807597683475
Measured from: -21.2080000042915
to: 53.1400000154972 [s; relative to TRIGTIME]
T50: 19.3319999873638 +/- 1.83051905035314
Measured from: -5.60799998044968
to: 13.7240000069141 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 1.4040000140667
to: 2.4040000140667 [s; relative to TRIGTIME]
Total Fluence
Measured from: -29.136000007391
to: 100.272000014782 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 4.978375 7.449881 6.424807 1.512779
0.166448 0.179099 0.162643 0.131409 [error]
Peak 0.167633 0.290599 0.263210 0.091610
0.023303 0.028281 0.025913 0.018814 [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 2.12e-06 3.69e-06 4.91e-06 1.34e-05 1.43e-05 2.42e-05 erg/cm2
Error 1.26e-07 1.29e-07 1.67e-07 1.04e-06 4.22e-07 1.13e-06 erg/cm2
Peak flux Power-law 2.34e+00 2.36e+00 1.67e+00 1.88e+00 7.12e+00 8.25e+00 ph/cm2/s
Error 4.09e-01 2.66e-01 1.97e-01 4.33e-01 7.60e-01 8.39e-01 ph/cm2/s
Fluence Cutoff-PL 1.89e-06 3.77e-06 5.14e-06 8.38e-06 1.40e-05 1.92e-05 erg/cm2
Error 1.68e-07 1.39e-07 2.06e-07 2.03e-06 4.47e-07 2.05e-06 erg/cm2
Peak flux Cutoff-PL 1.93e+00 2.53e+00 1.89e+00 9.83e-01 6.96e+00 7.33e+00 ph/cm2/s
Error 4.99e-01 3.14e-01 2.63e-01 5.28e-01 7.71e-01 9.27e-01 ph/cm2/s
Fluence Band 1.87e-06 3.75e-06 5.13e-06 8.37e-06 1.40e-05 1.91e-05 erg/cm2
Error 1.66e-07 1.38e-07 2.06e-07 2.03e-06 4.49e-07 2.05e-06 erg/cm2
Peak flux Band 1.93e+00 2.53e+00 1.89e+00 9.84e-01 6.96e+00 7.33e+00 ph/cm2/s
Error 4.99e-01 3.14e-01 2.63e-01 5.27e-01 7.71e-01 9.27e-01 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.587 0.054 - - 1.18e-02 3.43e-04 61.246 57
CPL 1.161 0.235 113.5 42.1 1.82e-02 4.28e-03 50.738 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.499 0.158 - - 5.70e-02 5.81e-03 52.610 57
CPL 0.632 0.721 88.3 58.2 1.45e-01 1.28e-01 47.269 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: 83.776000 sec.
T50 in the 50-300 keV band: 22.976000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 129.408 -29.136 100.272
T90 74.348 -21.208 53.140
T50 19.332 -5.608 13.724
Peak 1.000 1.404 2.404
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
121.2457 -45.5632 0.0061 48.3 146.8 16.9118 31.5 TRIG_00276321
------------------------------------------
Foreground time interval of the image:
-29.136 21.877 (delta_t = 51.013 [sec])
Background time interval of the image:
-240.424 -29.136 (delta_t = 211.288 [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
Time interval is from -29.136 sec. to 100.272 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.58653 ( -5.384588E-02 5.382264E-02) )
Norm@50keV : 1.180711E-02 ( -3.426913E-04 3.426485E-04) )
------------------------------------------------------------
Chi-Squared = 61.24590 using 59 PHA bins.
Reduced chi-squared = 1.074489 for 57 degrees of freedom
Null hypothesis probability = 0.326
Photon flux (15-150 keV) in 129.4 sec: 1.51100 ( -0.0514 0.05166 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.43125e-05 ( -4.21456e-07 4.21585e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -29.136 sec. to 100.272 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.16050 ( -0.241352 0.228403 )
Epeak [keV] : 113.509 ( -21.5324 62.7103 )
Norm@50keV : 1.817924E-02 ( -3.674584E-03 4.883187E-03) )
------------------------------------------------------------
Chi-Squared = 50.73812 using 59 PHA bins.
Reduced chi-squared = 0.9060379 for 56 degrees of freedom
Null hypothesis probability = 0.674
Photon flux (15-150 keV) in 129.4 sec: 1.46212 ( -0.05651 0.05693 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.40475e-05 ( -4.51606e-07 4.41642e-07 ) ergs/cm2
Band function
Time interval is from -29.136 sec. to 100.272 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.16056 ( -0.228315 0.241463 )
beta : -8.38729 ( -1.61271 6.63160 )
Epeak [keV] : 113.499 ( -21.5402 62.7226 )
Norm@50keV : 1.817606E-02 ( -3.673293E-03 4.885886E-03) )
------------------------------------------------------------
Chi-Squared = 50.73820 using 59 PHA bins.
Reduced chi-squared = 0.9225128 for 55 degrees of freedom
Null hypothesis probability = 0.638
Photon flux (15-150 keV) in 129.4 sec: 1.46213 ( -0.05654 0.05692 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.40343e-05 ( -4.507e-07 4.48112e-07 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 1.404 sec. to 2.404 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.49907 ( -0.157243 0.159371 )
Norm@50keV : 5.700777E-02 ( -5.811032E-03 5.807005E-03) )
------------------------------------------------------------
Chi-Squared = 52.61022 using 59 PHA bins.
Reduced chi-squared = 0.9229863 for 57 degrees of freedom
Null hypothesis probability = 0.640
Photon flux (15-150 keV) in 1.000 sec: 7.11503 ( -0.75899 0.76084 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.40886e-07 ( -5.7958e-08 5.8082e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 1.404 sec. to 2.404 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.631792 ( -0.784836 0.657073 )
Epeak [keV] : 88.3369 ( -20.3253 96.0857 )
Norm@50keV : 0.145018 ( -7.222429E-02 0.183526 )
------------------------------------------------------------
Chi-Squared = 47.26868 using 59 PHA bins.
Reduced chi-squared = 0.8440836 for 56 degrees of freedom
Null hypothesis probability = 0.791
Photon flux (15-150 keV) in 1.000 sec: 6.96449 ( -0.77005 0.7716 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.37008e-07 ( -6.0259e-08 5.9804e-08 ) ergs/cm2
Band function
Time interval is from 1.404 sec. to 2.404 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.633253 ( -0.655613 0.784770 )
beta : -8.95345 ( -1.04655 7.30902 )
Epeak [keV] : 88.3739 ( -20.3816 96.1077 )
Norm@50keV : 0.144796 ( -7.207254E-02 0.184422 )
------------------------------------------------------------
Chi-Squared = 47.26885 using 59 PHA bins.
Reduced chi-squared = 0.8594336 for 55 degrees of freedom
Null hypothesis probability = 0.761
Photon flux (15-150 keV) in 1.000 sec: 6.96450 ( -0.77056 0.77164 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.36673e-07 ( -6.022e-08 5.9767e-08 ) ergs/cm2
Plot creation:
Thu Dec 13 18:51:47 EST 2007