batgrbproduct Analysis for Trigger=312242
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): Sat May 24 03:07:21 EDT 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger312242/GCN5_download_cron
======================================================================
Trigger: 00312242 Segment: 000
BAT Trigger Time: 233270514.112 [s; MET]
Trigger Stop: 233270517.184 [s; MET]
UTC: 2008-05-23T21:21:51.299440 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 20.7319456343948 Dec: -64.0535352908149 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 7
Image Trigger?: NO
Rate S/N Ratio: 11.2249721603218 [ if not an image trigger ]
Image S/N Ratio: 7
Flight Position: [ source = BAT ]
RA: 20.7319456343948 Dec: -64.0535352908149 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 20.7685100413935 Dec: -64.0599929125925 [deg; J2000]
{ 01h 23m 04.4s , -64d 03' 36.0" }
+/- 1.71307258389311 [arcmin] (estimated 90% radius based on SNR)
+/- 0.718752665492391 [arcmin] (formal 1-sigma fit error)
SNR: 14.0978537814953
Angular difference between Flight and Ground position is 1.035030 arcmin
Partial Coding Fraction: 1.015625 [ including projection effects ]
Duration
T90: 102 +/- 15.2970585407784
Measured from: -4.11199998855591
to: 97.8880000114441 [s; relative to TRIGTIME]
T50: 30 +/- 11.1803398874989
Measured from: 2.88800001144409
to: 32.8880000114441 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 3.88800001144409
to: 4.88800001144409 [s; relative to TRIGTIME]
Total Fluence
Measured from: -6.11199998855591
to: 111.888000011444 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.501588 0.556777 0.398991 0.060356
0.050254 0.050663 0.044695 0.038365 [error]
Peak 0.023614 0.019795 0.017848 0.006222
0.004679 0.004833 0.004355 0.003549 [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 1.39e-07 2.34e-07 2.98e-07 7.62e-07 8.83e-07 1.43e-06 erg/cm2
Error 2.17e-08 2.30e-08 4.29e-08 2.29e-07 1.01e-07 2.67e-07 erg/cm2
Peak flux Power-law 1.86e-01 1.70e-01 1.07e-01 1.03e-01 5.06e-01 5.66e-01 ph/cm2/s
Error 6.65e-02 3.74e-02 3.70e-02 7.40e-02 1.11e-01 1.30e-01 ph/cm2/s
Fluence Cutoff-PL 1.28e-07 2.51e-07 3.06e-07 3.14e-07 8.41e-07 9.97e-07 erg/cm2
Error 2.56e-08 2.98e-08 4.75e-08 3.60e-07 1.11e-07 3.78e-07 erg/cm2
Peak flux Cutoff-PL 1.86e-01 1.70e-01 1.07e-01 1.02e-01 5.06e-01 5.65e-01 ph/cm2/s
Error 6.65e-02 3.74e-02 3.70e-02 7.35e-02 1.11e-01 1.29e-01 ph/cm2/s
Fluence Band 1.27e-07 2.50e-07 3.05e-07 3.15e-07 8.40e-07 9.97e-07 erg/cm2
Error 2.54e-08 2.97e-08 4.74e-08 3.60e-07 1.11e-07 3.68e-07 erg/cm2
Peak flux Band 1.80e-01 1.69e-01 1.10e-01 9.11e-02 5.11e-01 5.85e-01 ph/cm2/s
Error 6.57e-02 3.69e-02 2.66e-02 6.84e-02 1.11e-01 1.28e-01 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.650 0.176 - - 8.04e-04 8.55e-05 52.980 57
CPL 0.965 0.749 72.0 4973.1 1.83e-03 2.21e-03 50.681 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.668 0.448 - - 3.85e-03 9.95e-04 52.661 57
CPL 1.668 0.450 9999.3 5000.0 3.86e-03 1.00e-03 52.665 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: 30.784000 sec.
T50 in the 50-300 keV band: 18.560000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 118.000 -6.112 111.888
T90 102.000 -4.112 97.888
T50 30.000 2.888 32.888
Peak 1.000 3.888 4.888
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
20.7685 -64.0600 0.0136 9.7 -170.8 1.1400 14.1 TRIG_00312242
------------------------------------------
Foreground time interval of the image:
-6.112 39.289 (delta_t = 45.401 [sec])
Background time interval of the image:
-48.611 -6.112 (delta_t = 42.499 [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 -6.112 sec. to 111.888 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.64955 ( -0.174081 0.178416 )
Norm@50keV : 8.043761E-04 ( -8.605159E-05 8.490676E-05) )
------------------------------------------------------------
Chi-Squared = 52.98038 using 59 PHA bins.
Reduced chi-squared = 0.9294804 for 57 degrees of freedom
Null hypothesis probability = 0.627
Photon flux (15-150 keV) in 118.0 sec: 0.105015 ( -0.0102894 0.010298 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.82817e-07 ( -1.00278e-07 1.01787e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -6.112 sec. to 111.888 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.965229 ( -0.744760 0.752908 )
Epeak [keV] : 71.9617 ( -18.1431 9928.04 )
Norm@50keV : 1.832672E-03 ( -1.832672E-03 2.592126E-03) )
------------------------------------------------------------
Chi-Squared = 50.68102 using 59 PHA bins.
Reduced chi-squared = 0.9050182 for 56 degrees of freedom
Null hypothesis probability = 0.676
Photon flux (15-150 keV) in 118.0 sec: 0.102335 ( -0.0107394 0.010716 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.40992e-07 ( -1.09504e-07 1.12037e-07 ) ergs/cm2
Band function
Time interval is from -6.112 sec. to 111.888 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.03741 ( -0.677348 0.691199 )
beta : -8.02745 ( -1.97255 6.44454 )
Epeak [keV] : 74.8561 ( -20.1390 9925.14 )
Norm@50keV : 1.687659E-03 ( -1.687659E-03 2.725149E-03) )
------------------------------------------------------------
Chi-Squared = 50.65320 using 59 PHA bins.
Reduced chi-squared = 0.9209673 for 55 degrees of freedom
Null hypothesis probability = 0.641
Photon flux (15-150 keV) in 118.0 sec: 0.102357 ( -0.0107742 0.010712 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.40402e-07 ( -1.09564e-07 1.11778e-07 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 3.888 sec. to 4.888 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.66831 ( -0.430615 0.464462 )
Norm@50keV : 3.853697E-03 ( -1.030470E-03 9.591614E-04) )
------------------------------------------------------------
Chi-Squared = 52.66101 using 59 PHA bins.
Reduced chi-squared = 0.9238775 for 57 degrees of freedom
Null hypothesis probability = 0.638
Photon flux (15-150 keV) in 1.000 sec: 0.506282 ( -0.110533 0.110542 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.57822e-08 ( -9.7461e-09 1.01056e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 3.888 sec. to 4.888 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.66806 ( -0.433906 0.465727 )
Epeak [keV] : 9999.31 ( -9999.30 0.687500 )
Norm@50keV : 3.858995E-03 ( -1.036379E-03 9.675466E-04) )
------------------------------------------------------------
Chi-Squared = 52.66504 using 59 PHA bins.
Reduced chi-squared = 0.9404470 for 56 degrees of freedom
Null hypothesis probability = 0.602
Photon flux (15-150 keV) in 1.000 sec: 0.506092 ( -0.110502 0.110512 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.57548e-08 ( -9.7243e-09 1.0133e-08 ) ergs/cm2
Band function
Time interval is from 3.888 sec. to 4.888 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.22712 ( -8.77288 3.39028 )
beta : -1.67437 ( -8.32563 0.434099 )
Epeak [keV] : 33.7446 ( )
Norm@50keV : 9.221525E-03 ( )
------------------------------------------------------------
Chi-Squared = 52.63075 using 59 PHA bins.
Reduced chi-squared = 0.9569227 for 55 degrees of freedom
Null hypothesis probability = 0.566
Photon flux (15-150 keV) in 1.000 sec: 0.510602 ( -0.110945 0.110889 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.62091e-08 ( -7.9495e-09 9.6173e-09 ) ergs/cm2
Plot creation:
Sat May 24 03:53:16 EDT 2008