batgrbproduct Analysis for Trigger=291587
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 13:48:16 EST 2007
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger291587/GCN5_download_cron
======================================================================
Trigger: 00291587 Segment: 000
BAT Trigger Time: 211927512.632 [s; MET]
Trigger Stop: 211927512.968 [s; MET]
UTC: 2007-09-19T20:45:10.396620 [includes UTCF correction]
Where From?: (*SHORT BURST*) Expanded to TRIGTIME - 8 ms to TRIGTIME + 320 ms
BAT
RA: 272.336670651643 Dec: -20.4448103472644 [deg; J2000]
Catalogged Source?: YES
Point Source?: YES
GRB Indicated?: NO [ by BAT flight software ]
Image S/N Ratio: 20.88
Image Trigger?: NO
Rate S/N Ratio: 255.998046867549 [ if not an image trigger ]
Image S/N Ratio: 20.88
Flight Position: [ source = BAT ]
RA: 272.336670651643 Dec: -20.4448103472644 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 272.319656238204 Dec: -20.4361925499371 [deg; J2000]
{ 18h 09m 16.7s , -20d 26' 10.3" }
+/- 0.459297024191475 [arcmin] (estimated 90% radius based on SNR)
+/- 0.140841812770574 [arcmin] (formal 1-sigma fit error)
SNR: 92.4361318535056
RA = 18h 9m 16.7s (272.319656 deg.)
Dec = -20d 26' 10" (-20.436193 deg.)
Angular difference between Flight and Ground position is 1.087390 arcmin
Partial Coding Fraction: 0.6171875 [ including projection effects ]
Duration
T90: 15.1599999964237 +/- 3.79600843376573
Measured from: 0.224000006914139
to: 15.3840000033379 [s; relative to TRIGTIME]
T50: 1.04800000786781 +/- 0.0178885400881622
Measured from: 0.456000000238419
to: 1.50400000810623 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 0.175999999046326
to: 1.17599999904633 [s; relative to TRIGTIME]
Total Fluence
Measured from: 0.0800000131130219
to: 19.5600000023842 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 10.782560 7.881909 1.423501 0.028237
0.056562 0.050055 0.030173 0.021420 [error]
Peak 6.644736 4.850388 0.795378 0.009372
0.038869 0.033220 0.014452 0.004964 [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 5.47e-06 3.32e-06 1.29e-06 6.72e-07 1.04e-05 1.07e-05 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 Power-law 1.26e+02 3.76e+01 6.12e+00 1.15e+00 1.71e+02 1.71e+02 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 Cutoff-PL 3.60e-06 3.64e-06 1.21e-06 9.49e-08 8.52e-06 8.04e-06 erg/cm2
Error 2.50e-07 7.96e-08 4.51e-08 2.00e-08 2.96e-07 0.00e+00 erg/cm2
Peak flux Cutoff-PL 7.29e+01 4.18e+01 6.65e+00 2.14e-01 1.22e+02 1.22e+02 ph/cm2/s
Error 5.12e+00 9.43e-01 1.96e-01 3.44e-02 5.58e+00 5.58e+00 ph/cm2/s
Fluence Band 3.47e-06 3.62e-06 1.21e-06 9.47e-08 8.48e-06 8.14e-06 erg/cm2
Error 7.58e-08 3.18e-08 4.17e-08 2.94e-07 0.00e+00 0.00e+00 erg/cm2
Peak flux Band 7.30e+01 4.18e+01 6.65e+00 2.16e-01 1.22e+02 1.22e+02 ph/cm2/s
Error 4.97e+00 8.62e-01 1.89e-01 6.63e-02 4.03e+00 5.18e+00 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 3.363 0.000 - - 3.69e-02 0.00e+00 337.593 57
CPL 1.112 0.282 17.4 3.4 5.68e-01 1.97e-01 45.521 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 3.619 0.000 - - 3.83e-01 0.00e+00 594.160 57
CPL 0.946 0.256 18.1 2.7 9.27e+00 2.84e+00 49.182 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: 19.008000 sec.
T50 in the 50-300 keV band: 1.216000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 19.480 0.080 19.560
T90 15.160 0.224 15.384
T50 1.048 0.456 1.504
Peak 1.000 0.176 1.176
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
272.3197 -20.4362 0.0021 31.1 -134.6 20.6906 92.4 TRIG_00291587
------------------------------------------
Foreground time interval of the image:
0.072 19.552 (delta_t = 19.480 [sec])
Background time interval of the image:
-10.640 0.072 (delta_t = 10.712 [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 0.072 sec. to 19.552 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 3.36294 ( )
Norm@50keV : 3.690449E-02 ( )
------------------------------------------------------------
Chi-Squared = 337.5934 using 59 PHA bins.
Reduced chi-squared = 5.922691 for 57 degrees of freedom
Null hypothesis probability = 1.832E-41
Photon flux (15-150 keV) in 19.48 sec: 13.3732 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 1.04285e-05 ( 0 0 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.072 sec. to 19.552 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.11222 ( -0.288712 0.274957 )
Epeak [keV] : 17.3778 ( -3.75947 3.09642 )
Norm@50keV : 0.567758 ( -0.159189 0.234521 )
------------------------------------------------------------
Chi-Squared = 45.52098 using 59 PHA bins.
Reduced chi-squared = 0.8128746 for 56 degrees of freedom
Null hypothesis probability = 0.840
Photon flux (15-150 keV) in 19.48 sec: 10.1340 ( -0.47003 0.479 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.52334e-06 ( -2.9294e-07 2.99076e-07 ) ergs/cm2
Band function
Time interval is from 0.072 sec. to 19.552 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.23755 ( -5.313385E-02 2.307904E-02) )
beta : -9.20582 ( -0.666601 4.38331 )
Epeak [keV] : 16.6211 ( -3.47554 4.16161 )
Norm@50keV : 0.450001 ( -0.148858 0.282138 )
------------------------------------------------------------
Chi-Squared = 58.56461 using 59 PHA bins.
Reduced chi-squared = 1.064811 for 55 degrees of freedom
Null hypothesis probability = 0.346
Photon flux (15-150 keV) in 19.48 sec: 10.0981 ( -0.42403 0.516 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.47937e-06 ( -2.68512e-07 3.19199e-07 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 0.168 sec. to 1.168 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 3.61917 ( )
Norm@50keV : 0.383010 ( )
------------------------------------------------------------
Chi-Squared = 594.1601 using 59 PHA bins.
Reduced chi-squared = 10.42386 for 57 degrees of freedom
Null hypothesis probability = 0.00
Photon flux (15-150 keV) in 1.000 sec: 170.822 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 6.49498e-06 ( 0 0 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.168 sec. to 1.168 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.946022 ( -0.262978 0.249186 )
Epeak [keV] : 18.1127 ( -2.89070 2.53094 )
Norm@50keV : 9.27028 ( -2.34027 3.33915 )
------------------------------------------------------------
Chi-Squared = 49.18222 using 59 PHA bins.
Reduced chi-squared = 0.8782540 for 56 degrees of freedom
Null hypothesis probability = 0.729
Photon flux (15-150 keV) in 1.000 sec: 121.564 ( -5.52 5.641 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.17411e-06 ( -1.73825e-07 1.77902e-07 ) ergs/cm2
Band function
Time interval is from 0.168 sec. to 1.168 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.35150 ( )
beta : -9.37167 ( )
Epeak [keV] : 17.5773 ( )
Norm@50keV : 3.18133 ( )
------------------------------------------------------------
Chi-Squared = 464.4281 using 59 PHA bins.
Reduced chi-squared = 8.444148 for 55 degrees of freedom
Null hypothesis probability = 0.00
Photon flux (15-150 keV) in 1.000 sec: 121.667 ( -5.317 2.746 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.0072e-06 ( -1.36533e-07 1.10118e-07 ) ergs/cm2
Plot creation:
Fri Dec 14 13:57:39 EST 2007