batgrbproduct Analysis for Trigger=312582
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): Wed May 28 18:56:47 EDT 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger312582/GCN5_download_cron
======================================================================
Trigger: 00312582 Segment: 000
BAT Trigger Time: 233661183.616 [s; MET]
Trigger Stop: 233661183.632 [s; MET]
UTC: 2008-05-28T09:53:00.792420 [includes UTCF correction]
Where From?: (*SHORT BURST*) TDRSS scaled map message
BAT
RA: 248.95458870056 Dec: -47.5854822205534 [deg; J2000]
Catalogged Source?: YES
Point Source?: YES
GRB Indicated?: NO [ by BAT flight software ]
Image S/N Ratio: 25.15
Image Trigger?: NO
Rate S/N Ratio: 255.998046867549 [ if not an image trigger ]
Image S/N Ratio: 25.15
Flight Position: [ source = BAT ]
RA: 248.95458870056 Dec: -47.5854822205534 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 249.065819446148 Dec: -47.530743387153 [deg; J2000]
{ 16h 36m 15.8s , -47d 31' 50.7" }
+/- 4.08521364492459 [arcmin] (estimated 90% radius based on SNR)
+/- 2.26493067415234 [arcmin] (formal 1-sigma fit error)
SNR: 4.07337522298527
Angular difference between Flight and Ground position is 5.574132 arcmin
Partial Coding Fraction: 0.7734375 [ including projection effects ]
Duration
T90: 727.115999996662 +/- 191.040965041405
Measured from: -143.095999985933
to: 584.020000010729 [s; relative to TRIGTIME]
T50: 279.140000015497 +/- 168.433737310678
Measured from: 0.00400000810623169
to: 279.144000023603 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: -0.335999995470047
to: 0.664000004529953 [s; relative to TRIGTIME]
Total Fluence
Measured from: -176.016000002623
to: 740.56400001049 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 1.129595 0.948138 0.157017 -0.136029
0.205415 0.180776 0.150505 0.130594 [error]
Peak 0.478901 0.375636 0.095534 0.000654
0.012047 0.010554 0.006748 0.004437 [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 3.21e-07 3.33e-07 2.43e-07 2.86e-07 1.01e-06 1.18e-06 erg/cm2
Error 9.40e-08 8.94e-08 1.21e-07 3.24e-07 2.97e-07 4.57e-07 erg/cm2
Peak flux Power-law 5.99e+00 2.81e+00 8.02e-01 2.86e-01 9.77e+00 9.89e+00 ph/cm2/s
Error 3.91e-01 1.18e-01 5.78e-02 3.91e-02 4.73e-01 4.68e-01 ph/cm2/s
Fluence Cutoff-PL 2.95e-07 4.31e-07 6.74e-08 2.73e-10 7.93e-07 7.93e-07 erg/cm2
Error 1.04e-07 1.28e-07 1.33e-07 5.10e-08 2.35e-07 2.40e-07 erg/cm2
Peak flux Cutoff-PL 4.89e+00 3.14e+00 7.40e-01 5.81e-02 8.82e+00 8.82e+00 ph/cm2/s
Error 4.84e-01 1.47e-01 7.33e-02 2.76e-02 5.32e-01 5.34e-01 ph/cm2/s
Fluence Band 3.01e-07 4.17e-07 1.23e-07 2.80e-08 8.64e-07 8.81e-07 erg/cm2
Error 1.05e-07 1.21e-07 9.33e-08 1.56e-07 2.56e-07 3.33e-07 erg/cm2
Peak flux Band 4.87e+00 3.14e+00 7.40e-01 5.81e-02 8.82e+00 8.81e+00 ph/cm2/s
Error 2.45e-01 1.38e-01 3.76e-02 2.94e-02 3.71e-01 5.32e-01 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 2.453 0.489 - - 1.12e-04 4.17e-05 48.571 57
CPL 1.164 0.000 21.2 17.3 8.38e-04 0.00e+00 46.125 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 2.811 0.086 - - 4.06e-02 2.21e-03 88.013 57
CPL 1.264 0.477 19.3 7.2 3.11e-01 2.14e-01 44.450 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: 550.528000 sec.
T50 in the 50-300 keV band: 1.792000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 916.580 -176.016 740.564
T90 727.116 -143.096 584.020
T50 279.140 0.004 279.144
Peak 1.000 -0.336 0.664
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
249.0658 -47.5307 0.0476 22.9 34.3 2.4929 4.1 TRIG_00312582
------------------------------------------
Foreground time interval of the image:
-117.215 -63.886 (delta_t = 53.329 [sec])
-62.616 564.624 (delta_t = 627.240 [sec])
565.384 672.844 (delta_t = 107.460 [sec])
674.384 740.564 (delta_t = 66.180 [sec])
Background time interval of the image:
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
Multiple GTIs in the spectrum
tstart tstop
-176.016000 -63.886000
-62.616000 564.624000
565.384000 672.844000
674.384000 740.564000
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.45273 ( -0.451423 0.527211 )
Norm@50keV : 1.116555E-04 ( -4.154055E-05 4.193430E-05) )
------------------------------------------------------------
Chi-Squared = 48.57090 using 59 PHA bins.
Reduced chi-squared = 0.8521210 for 57 degrees of freedom
Null hypothesis probability = 0.779
Photon flux (15-150 keV) in 913.0 sec: 2.131455E-02 ( -0.00515277 0.00515317 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.00712e-06 ( -2.87123e-07 3.07581e-07 ) ergs/cm2
Cutoff power-law model
Multiple GTIs in the spectrum
tstart tstop
-176.016000 -63.886000
-62.616000 564.624000
565.384000 672.844000
674.384000 740.564000
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.16395 ( )
Epeak [keV] : 21.2080 ( -27.8368 6.83711 )
Norm@50keV : 8.378269E-04 ( )
------------------------------------------------------------
Chi-Squared = 46.12505 using 59 PHA bins.
Reduced chi-squared = 0.8236616 for 56 degrees of freedom
Null hypothesis probability = 0.824
Photon flux (15-150 keV) in 913.0 sec: 1.985410E-02 ( -0.00472813 0.00514657 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.93499e-07 ( -1.95279e-07 2.74829e-07 ) ergs/cm2
Band function
Multiple GTIs in the spectrum
tstart tstop
-176.016000 -63.886000
-62.616000 564.624000
565.384000 672.844000
674.384000 740.564000
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.54548 ( -8.45452 1.35039 )
beta : -9.28886 ( -0.711136 7.09822 )
Epeak [keV] : 17.2003 ( -17.1003 62.9142 )
Norm@50keV : 4.394199E-04 ( -9.533991E-02 8.89455 )
------------------------------------------------------------
Chi-Squared = 46.63388 using 59 PHA bins.
Reduced chi-squared = 0.8478888 for 55 degrees of freedom
Null hypothesis probability = 0.782
Photon flux (15-150 keV) in 913.0 sec: 2.069722E-02 ( -0.00484208 0.00484315 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.63701e-07 ( -2.1217e-07 3.00803e-07 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from -0.336 sec. to 0.664 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.81129 ( -8.534217E-02 8.722615E-02) )
Norm@50keV : 4.062314E-02 ( -2.218686E-03 2.205044E-03) )
------------------------------------------------------------
Chi-Squared = 88.01304 using 59 PHA bins.
Reduced chi-squared = 1.544088 for 57 degrees of freedom
Null hypothesis probability = 5.232E-03
Photon flux (15-150 keV) in 1.000 sec: 9.77420 ( -0.47074 0.4745 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.50365e-07 ( -1.8816e-08 1.8812e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.336 sec. to 0.664 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.26359 ( -0.500824 0.452787 )
Epeak [keV] : 19.2843 ( -8.91136 5.46926 )
Norm@50keV : 0.311268 ( -0.138435 0.289509 )
------------------------------------------------------------
Chi-Squared = 44.45028 using 59 PHA bins.
Reduced chi-squared = 0.7937550 for 56 degrees of freedom
Null hypothesis probability = 0.867
Photon flux (15-150 keV) in 1.000 sec: 8.81877 ( -0.53007 0.5332 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.0672e-07 ( -2.0922e-08 2.1229e-08 ) ergs/cm2
Band function
Time interval is from -0.336 sec. to 0.664 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.87386 ( )
beta : -8.31737 ( )
Epeak [keV] : 10.5101 ( )
Norm@50keV : 8.860398E-02 ( )
------------------------------------------------------------
Chi-Squared = 118.2032 using 59 PHA bins.
Reduced chi-squared = 2.149149 for 55 degrees of freedom
Null hypothesis probability = 1.619E-06
Photon flux (15-150 keV) in 1.000 sec: 8.81829 ( -0.52558 0.2163 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.05684e-07 ( -1.9229e-08 2.1224e-08 ) ergs/cm2
Plot creation:
Wed May 28 19:29:55 EDT 2008