batgrbproduct Analysis for Trigger=282225
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): Fri Dec 14 02:19:04 EST 2007
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger282225/GCN5_download_cron
======================================================================
Trigger: 00282225 Segment: 000
BAT Trigger Time: 203460127.808 [s; MET]
Trigger Stop: 203460129.856 [s; MET]
UTC: 2007-06-13T20:42:05.788200 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 299.596939731123 Dec: 35.2773962149263 [deg; J2000]
Catalogged Source?: YES
Point Source?: YES
GRB Indicated?: NO [ by BAT flight software ]
Image S/N Ratio: 8.59
Image Trigger?: NO
Rate S/N Ratio: 11.0905365064094 [ if not an image trigger ]
Image S/N Ratio: 8.59
Flight Position: [ source = BAT ]
RA: 299.596939731123 Dec: 35.2773962149263 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 299.602478947692 Dec: 35.2648052792066 [deg; J2000]
{ 19h 58m 24.6s , +35d 15' 53.3" }
+/- 2.49772223249668 [arcmin] (estimated 90% radius based on SNR)
+/- 1.14474202273111 [arcmin] (formal 1-sigma fit error)
SNR: 8.22617947686824
RA = 19h 58m 24.6s (299.602479 deg.)
Dec = 35d 15' 53" (35.264805 deg.)
Angular difference between Flight and Ground position is 0.802708 arcmin
Partial Coding Fraction: 1.015625 [ including projection effects ]
Duration
T90: 1.98399996757507 +/- 0.403821742918092
Measured from: 0.00800001621246338
to: 1.99199998378754 [s; relative to TRIGTIME]
T50: 1.23199996352196 +/- 0.531864647339814
Measured from: 0.488000005483627
to: 1.71999996900558 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 1.09999999403954
to: 2.09999999403954 [s; relative to TRIGTIME]
Total Fluence
Measured from: -0.0879999995231628
to: 2.19999998807907 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.092312 0.087890 0.042222 0.010500
0.008130 0.008052 0.007141 0.006505 [error]
Peak 0.038153 0.047128 0.017242 0.011068
0.005308 0.005393 0.004793 0.004319 [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 2.44e-08 3.49e-08 3.71e-08 7.31e-08 1.19e-07 1.75e-07 erg/cm2
Error 3.76e-09 3.65e-09 6.79e-09 2.70e-08 1.54e-08 3.45e-08 erg/cm2
Peak flux Power-law 3.54e-01 2.90e-01 1.61e-01 1.31e-01 8.63e-01 9.36e-01 ph/cm2/s
Error 7.44e-02 4.16e-02 3.84e-02 6.08e-02 1.24e-01 1.39e-01 ph/cm2/s
Fluence Cutoff-PL 2.42e-08 3.56e-08 3.68e-08 5.48e-08 1.17e-07 1.51e-07 erg/cm2
Error 3.97e-09 3.61e-09 7.39e-09 5.11e-08 1.42e-08 4.94e-08 erg/cm2
Peak flux Cutoff-PL 3.44e-01 3.04e-01 1.59e-01 7.22e-02 8.51e-01 8.80e-01 ph/cm2/s
Error 8.11e-02 5.89e-02 4.57e-02 9.76e-02 9.73e-02 1.69e-01 ph/cm2/s
Fluence Band 2.37e-08 3.65e-08 3.54e-08 6.10e-08 1.16e-07 1.54e-07 erg/cm2
Error 4.39e-09 5.11e-09 7.79e-09 3.30e-08 1.66e-08 3.91e-08 erg/cm2
Peak flux Band 3.33e-01 3.21e-01 1.49e-01 9.02e-02 8.48e-01 8.94e-01 ph/cm2/s
Error 8.29e-02 5.80e-02 4.51e-02 6.89e-02 1.27e-01 1.48e-01 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.912 0.205 - - 5.67e-03 7.42e-04 51.839 57
CPL 1.768 0.665 65.5 5000.0 6.90e-03 1.15e-02 51.754 0
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.849 0.274 - - 6.14e-03 1.10e-03 39.875 57
CPL 1.448 1.169 55.9 5000.0 1.06e-02 5.11e-02 39.554 0
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: 0.000000 sec.
T50 in the 50-300 keV band: 0.000000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 2.288 -0.088 2.200
T90 1.984 0.008 1.992
T50 1.232 0.488 1.720
Peak 1.000 1.100 2.100
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
299.6025 +35.2648 0.0235 9.1 -129.6 0.1350 8.2 TRIG_00282225
------------------------------------------
Foreground time interval of the image:
-0.088 2.200 (delta_t = 2.288 [sec])
Background time interval of the image:
-10.808 -0.088 (delta_t = 10.720 [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 -0.088 sec. to 2.200 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.91190 ( -0.200900 0.208887 )
Norm@50keV : 5.671832E-03 ( -7.513147E-04 7.332014E-04) )
------------------------------------------------------------
Chi-Squared = 51.83945 using 59 PHA bins.
Reduced chi-squared = 0.9094640 for 57 degrees of freedom
Null hypothesis probability = 0.668
Photon flux (15-150 keV) in 2.288 sec: 0.818109 ( -0.085248 0.085263 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.19294e-07 ( -1.51644e-08 1.56161e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.088 sec. to 2.200 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.76792 ( -0.884719 0.445864 )
Epeak [keV] : 65.5394 ( -65.5294 9934.46 )
Norm@50keV : 6.896179E-03 ( -6.896179E-03 1.615581E-02) )
------------------------------------------------------------
Chi-Squared = 51.75422 using 59 PHA bins.
but latest trial 2.21379 gives Chi-Squared = 1.04450
Reduced chi-squared = 0.9241825 for 56 degrees of freedom
Null hypothesis probability = 0.636
Photon flux (15-150 keV) in 2.288 sec: 0.813520 ( -0.044612 0.086438 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.1719e-07 ( -1.91087e-08 9.19845e-09 ) ergs/cm2
Band function
Time interval is from -0.088 sec. to 2.200 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.919597 ( -10.5804 3.50152 )
beta : -2.04871 ( -0.350031 0.302675 )
Epeak [keV] : 32.5104 ( -27.3368 823.432 )
Norm@50keV : 2.727255E-02 ( -268.877 480.439 )
------------------------------------------------------------
Chi-Squared = 50.68098 using 59 PHA bins.
Reduced chi-squared = 0.9214723 for 55 degrees of freedom
Null hypothesis probability = 0.640
Photon flux (15-150 keV) in 2.288 sec: 0.811902 ( -0.08574 0.09067 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.16145e-07 ( -1.6329e-08 1.6901e-08 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 1.096 sec. to 2.104 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.84906 ( -0.265315 0.282539 )
Norm@50keV : 6.141920E-03 ( -1.121162E-03 1.084851E-03) )
------------------------------------------------------------
Chi-Squared = 39.87527 using 59 PHA bins.
Reduced chi-squared = 0.6995661 for 57 degrees of freedom
Null hypothesis probability = 0.959
Photon flux (15-150 keV) in 1.008 sec: 0.862981 ( -0.12385 0.123856 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.68927e-08 ( -1.01096e-08 1.05296e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 1.096 sec. to 2.104 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.44754 ( -1.60383 0.733860 )
Epeak [keV] : 55.8989 ( -55.8889 9944.10 )
Norm@50keV : 1.062152E-02 ( -1.062152E-02 9.153246E-02) )
------------------------------------------------------------
Chi-Squared = 39.55443 using 59 PHA bins.
but latest trial 2.18140 gives Chi-Squared = 45.7754
Reduced chi-squared = 0.7063290 for 56 degrees of freedom
Null hypothesis probability = 0.953
Photon flux (15-150 keV) in 1.008 sec: 0.851063 ( -0.129931 0.064596 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.42235e-08 ( -1.28981e-08 1.25312e-08 ) ergs/cm2
Band function
Time interval is from 1.096 sec. to 2.104 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.558733 ( -9.52127 4.26527 )
beta : -2.17958 ( -7.81625 0.526745 )
Epeak [keV] : 37.6162 ( -37.2551 9962.64 )
Norm@50keV : 4.201235E-02 ( -4.740009E-02 353.061 )
------------------------------------------------------------
Chi-Squared = 38.58374 using 59 PHA bins.
Reduced chi-squared = 0.7015225 for 55 degrees of freedom
Null hypothesis probability = 0.954
Photon flux (15-150 keV) in 1.008 sec: 0.847563 ( -0.127744 0.126016 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.36102e-08 ( -1.11777e-08 1.15277e-08 ) ergs/cm2
Plot creation:
Fri Dec 14 02:24:44 EST 2007