batgrbproduct Analysis for Trigger=308041
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): Sun Mar 30 15:40:26 EDT 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger308041/GCN5_download_cron
======================================================================
Trigger: 00308041 Segment: 000
BAT Trigger Time: 228541279.552 [s; MET]
Trigger Stop: 228541280.576 [s; MET]
UTC: 2008-03-30T03:41:16.872120 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 169.301665972192 Dec: 30.5703275537686 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 7.58
Image Trigger?: NO
Rate S/N Ratio: 10.9544511501033 [ if not an image trigger ]
Image S/N Ratio: 7.58
Flight Position: [ source = BAT ]
RA: 169.301665972192 Dec: 30.5703275537686 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 169.278030736215 Dec: 30.6066848667193 [deg; J2000]
{ 11h 17m 06.7s , +30d 36' 24.1" }
+/- 1.83609431611202 [arcmin] (estimated 90% radius based on SNR)
+/- 0.773476431049092 [arcmin] (formal 1-sigma fit error)
SNR: 12.7680784546114
RA = 11h 17m 6.7s (169.278031 deg.)
Dec = 30d 36' 24" (30.606685 deg.)
Angular difference between Flight and Ground position is 2.499793 arcmin
Partial Coding Fraction: 0.53125 [ including projection effects ]
Duration
T90: 60.7040000259876 +/- 6.37273599106372
Measured from: 0.0200000107288361
to: 60.7240000367165 [s; relative to TRIGTIME]
T50: 55.8360000252724 +/- 48.6701097469851
Measured from: 1.63199999928474
to: 57.4680000245571 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 0.440000027418137
to: 1.44000002741814 [s; relative to TRIGTIME]
Total Fluence
Measured from: -0.479999989271164
to: 71.9000000059605 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.345732 0.256091 0.084638 0.066193
0.045362 0.045203 0.040003 0.035400 [error]
Peak 0.058781 0.026240 0.018596 0.005891
0.007174 0.007169 0.005814 0.004992 [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 1.15e-07 1.14e-07 7.92e-08 8.69e-08 3.43e-07 3.95e-07 erg/cm2
Error 2.52e-08 2.47e-08 3.65e-08 7.78e-08 8.21e-08 1.29e-07 erg/cm2
Peak flux Power-law 5.37e-01 2.83e-01 9.28e-02 3.92e-02 9.34e-01 9.52e-01 ph/cm2/s
Error 1.43e-01 7.09e-02 5.21e-02 4.22e-02 1.84e-01 1.90e-01 ph/cm2/s
Fluence Cutoff-PL 1.15e-07 1.14e-07 7.91e-08 8.60e-08 3.42e-07 3.97e-07 erg/cm2
Error 2.52e-08 2.47e-08 3.65e-08 7.71e-08 8.21e-08 1.28e-07 erg/cm2
Peak flux Cutoff-PL 5.37e-01 2.83e-01 9.26e-02 3.89e-02 9.34e-01 9.51e-01 ph/cm2/s
Error 1.43e-01 7.09e-02 5.21e-02 4.18e-02 1.84e-01 1.90e-01 ph/cm2/s
Fluence Band 1.08e-07 1.16e-07 8.43e-08 9.82e-08 3.46e-07 4.53e-07 erg/cm2
Error 1.94e-08 2.08e-08 1.67e-08 5.74e-08 9.38e-08 0.00e+00 erg/cm2
Peak flux Band 5.21e-01 2.89e-01 1.83e-01 1.22e+00 2.91e+01 9.57e-01 ph/cm2/s
Error 1.30e-01 2.32e+03 3.13e+03 1.88e-01 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 2.525 0.452 - - 4.70e-04 1.57e-04 70.361 57
CPL 1.863 0.000 7.5 0.0 1.22e-03 6.09e-03 71.845 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 2.608 0.593 - - 4.44e-03 1.87e-03 33.368 57
CPL 1.984 0.372 1.4 0.0 9.12e-03 3.54e-03 35.609 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 72.380 -0.480 71.900
T90 60.704 0.020 60.724
T50 55.836 1.632 57.468
Peak 1.000 0.440 1.440
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
169.2780 +30.6067 0.0150 27.7 53.9 0.5132 12.8 TRIG_00308041
------------------------------------------
Foreground time interval of the image:
-0.480 9.849 (delta_t = 10.329 [sec])
Background time interval of the image:
-239.552 -64.842 (delta_t = 174.710 [sec])
-63.552 -0.480 (delta_t = 63.072 [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 -0.480 sec. to 71.900 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.52528 ( -0.413941 0.490762 )
Norm@50keV : 4.699168E-04 ( -1.581248E-04 1.564089E-04) )
------------------------------------------------------------
Chi-Squared = 70.36142 using 59 PHA bins.
Reduced chi-squared = 1.234411 for 57 degrees of freedom
Null hypothesis probability = 0.110
Photon flux (15-150 keV) in 72.38 sec: 9.376329E-02 ( -0.0163295 0.0163397 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.42533e-07 ( -7.9023e-08 8.5137e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.480 sec. to 71.900 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.86251 ( )
Epeak [keV] : 7.45632 ( )
Norm@50keV : 1.219462E-03 ( -1.213362E-03 1.096878E-02) )
------------------------------------------------------------
Chi-Squared = 71.84504 using 59 PHA bins.
Reduced chi-squared = 1.282947 for 56 degrees of freedom
Null hypothesis probability = 7.533E-02
Photon flux (15-150 keV) in 72.38 sec: 9.372242E-02 ( -0.0163235 0.0163336 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.42385e-07 ( -7.8942e-08 8.51674e-08 ) ergs/cm2
Band function
Time interval is from -0.480 sec. to 71.900 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.51659 ( -1.19350 13.8065 )
beta : -2.43412 ( -0.490916 0.413774 )
Epeak [keV] : 10.5531 ( -10.4531 9989.45 )
Norm@50keV : 2.904046E-03 ( -2.149729E-02 2.126461E-02) )
------------------------------------------------------------
Chi-Squared = 70.59564 using 59 PHA bins.
Reduced chi-squared = 1.283557 for 55 degrees of freedom
Null hypothesis probability = 7.662E-02
Photon flux (15-150 keV) in 72.38 sec: 9.375235E-02 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 3.45991e-07 ( -5.44037e-08 6.04786e-08 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 0.440 sec. to 1.440 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.60846 ( -0.515925 0.670106 )
Norm@50keV : 4.441385E-03 ( -1.911183E-03 1.825756E-03) )
------------------------------------------------------------
Chi-Squared = 33.36834 using 59 PHA bins.
Reduced chi-squared = 0.5854095 for 57 degrees of freedom
Null hypothesis probability = 0.995
Photon flux (15-150 keV) in 1.000 sec: 0.934393 ( -0.18443 0.184397 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.58977e-08 ( -1.2412e-08 1.32571e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.440 sec. to 1.440 sec.
Parameters : value lower 90% higher 90%
Photon index: 1.98403 ( -0.719760 2.391541E-02) )
Epeak [keV] : 1.38893 ( )
Norm@50keV : 9.115274E-03 ( -4.059809E-03 3.020073E-03) )
------------------------------------------------------------
Chi-Squared = 35.60894 using 59 PHA bins.
but latest trial 2.00221 gives Chi-Squared = 1.59613
but latest trial 5.153640E-03 gives Chi-Squared = 2.72529
Reduced chi-squared = 0.6358739 for 56 degrees of freedom
Null hypothesis probability = 0.985
Photon flux (15-150 keV) in 1.000 sec: 0.933927 ( -0.184371 0.184333 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.58277e-08 ( -1.23585e-08 1.33074e-08 ) ergs/cm2
Band function
Time interval is from 0.440 sec. to 1.440 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.56637 ( -2.632141E-04 14.9997 )
beta : -1.79693 ( -0.671076 0.514686 )
Epeak [keV] : 4.56890 ( -4.46890 9995.43 )
Norm@50keV : 1.569167E-02 ( -0.260707 0.247429 )
------------------------------------------------------------
Chi-Squared = 40.55082 using 59 PHA bins.
Reduced chi-squared = 0.7372876 for 55 degrees of freedom
Null hypothesis probability = 0.927
Photon flux (15-150 keV) in 1.000 sec: 29.1219 ( -29.1219 6221.76 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.54276e-08 ( -1.01091e-08 8.9402e-09 ) ergs/cm2
Plot creation:
Sun Mar 30 16:11:39 EDT 2008