batgrbproduct Analysis for Trigger=277982
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): Thu Dec 13 20:04:31 EST 2007
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger277982/SDC
======================================================================
Trigger: 00277982 Segment: 000
BAT Trigger Time: 199759272 [s; MET]
Trigger Stop: 199759336 [s; MET]
UTC: 2007-05-02T00:41:10.072560 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 315.875956990412 Dec: 45.7263172895614 [deg; J2000]
Catalogged Source?: YES
Point Source?: YES
GRB Indicated?: NO [ by BAT flight software ]
Image S/N Ratio: 6.91
Image Trigger?: YES
Rate S/N Ratio: 0 [ if not an image trigger ]
Image S/N Ratio: 6.91
Flight Position: [ source = BAT ]
RA: 315.875956990412 Dec: 45.7263172895614 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 315.961579990099 Dec: 45.6695308008749 [deg; J2000]
{ 21h 03m 50.8s , +45d 40' 10.3" }
+/- 3.22034515368072 [arcmin] (estimated 90% radius based on SNR)
+/- 1.76659130792409 [arcmin] (formal 1-sigma fit error)
SNR: 5.72194253830101
RA = 21h 3m 50.8s (315.961580 deg.)
Dec = 45d 40' 10" (45.669531 deg.)
Angular difference between Flight and Ground position is 4.948112 arcmin
Partial Coding Fraction: 1 [ including projection effects ]
Duration
T90: 64 +/-
Measured from: 0
to: 64 [s; relative to TRIGTIME]
T50: 64 +/-
Measured from: 0
to: 64 [s; relative to TRIGTIME]
WARNING: battblocks failed. Used TDRSS fore/background intervals
Fluence
Peak Flux (peak 64 second)
Measured from: 0
to: 64 [s; relative to TRIGTIME]
Total Fluence
Measured from: 0
to: 64 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.092245 0.152095 0.015919 0.015923
0.026586 0.026584 0.023082 0.019892 [error]
Peak 0.092245 0.152095 0.015919 0.015923
0.026586 0.026584 0.023082 0.019892 [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 3.70e-08 4.05e-08 3.15e-08 4.02e-08 1.24e-07 1.49e-07 erg/cm2
Error 1.12e-08 1.22e-08 1.78e-08 4.96e-08 4.29e-08 7.04e-08 erg/cm2
Peak flux Power-law 3.68e-02 2.24e-02 8.70e-03 4.54e-03 7.02e-02 7.24e-02 ph/cm2/s
Error 1.13e-02 6.55e-03 4.77e-03 5.27e-03 1.84e-02 1.95e-02 ph/cm2/s
Fluence Cutoff-PL 3.34e-08 5.49e-08 9.48e-09 4.10e-11 9.78e-08 9.76e-08 erg/cm2
Error 1.16e-08 1.72e-08 1.92e-08 1.38e-08 3.33e-08 3.64e-08 erg/cm2
Peak flux Cutoff-PL 3.18e-02 3.09e-02 3.05e-03 7.21e-06 6.58e-02 6.58e-02 ph/cm2/s
Error 1.18e-02 9.29e-03 5.43e-03 1.72e-03 1.73e-02 1.73e-02 ph/cm2/s
Fluence Band 3.59e-08 5.72e-08 1.02e-08 1.04e-09 9.84e-08 1.11e-07 erg/cm2
Error 1.47e-08 1.22e-08 6.45e-09 3.05e-08 7.17e-08 0.00e+00 erg/cm2
Peak flux Band 3.39e-02 3.01e-02 4.32e-03 3.79e-04 6.72e-02 6.84e-02 ph/cm2/s
Error 1.35e-02 9.54e-03 5.16e-03 1.39e-03 1.69e-02 1.74e-02 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 2.361 0.542 - - 3.88e-04 1.65e-04 63.070 57
CPL -1.243 0.000 29.1 18.9 9.77e-02 3.62e-01 60.066 0
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 2.361 0.542 - - 3.88e-04 1.65e-04 63.070 57
CPL -1.243 0.000 29.1 18.9 9.77e-02 3.62e-01 60.066 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 64.000 0.000 64.000
T90 64.000 0.000 64.000
T50 64.000 0.000 64.000
Peak 64.000 0.000 64.000
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
315.9616 +45.6695 0.0333 0.1 32.0 0.3013 5.7 TRIG_00277982
------------------------------------------
Foreground time interval of the image:
0.000 33.060 (delta_t = 33.060 [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
Time interval is from 0.000 sec. to 33.059 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.36112 ( -0.484605 0.599978 )
Norm@50keV : 3.879637E-04 ( -1.642590E-04 1.648724E-04) )
------------------------------------------------------------
Chi-Squared = 63.06989 using 59 PHA bins.
Reduced chi-squared = 1.106489 for 57 degrees of freedom
Null hypothesis probability = 0.270
Photon flux (15-150 keV) in 33.06 sec: 7.016895E-02 ( -0.01838 0.0184292 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.24012e-07 ( -4.08615e-08 4.50383e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.000 sec. to 33.059 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.24284 ( )
Epeak [keV] : 29.0646 ( -29.0535 8.69151 )
Norm@50keV : 9.769993E-02 ( -0.111415 0.613459 )
------------------------------------------------------------
Chi-Squared = 60.06584 using 59 PHA bins.
but latest trial 0.997401 gives Chi-Squared = 6.83609
Reduced chi-squared = 1.072604 for 56 degrees of freedom
Null hypothesis probability = 0.331
Photon flux (15-150 keV) in 33.06 sec: 6.578572E-02 ( -0.016413 0.0182629 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.7815e-08 ( -2.6123e-08 4.04254e-08 ) ergs/cm2
Band function
Time interval is from 0.000 sec. to 33.059 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.51626 ( -8.32374 0.577325 )
beta : -6.42282 ( -0.730639 7.28002 )
Epeak [keV] : 13.4519 ( -6.21385 2371.78 )
Norm@50keV : 1.884976E-03 ( -0.630336 20.9722 )
------------------------------------------------------------
Chi-Squared = 62.29927 using 59 PHA bins.
Reduced chi-squared = 1.132714 for 55 degrees of freedom
Null hypothesis probability = 0.233
Photon flux (15-150 keV) in 33.06 sec: 6.718653E-02 ( -0.0168858 0.0170116 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.84236e-08 ( -2.68576e-08 3.40743e-08 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 0.000 sec. to 33.059 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.36112 ( -0.484605 0.599978 )
Norm@50keV : 3.879637E-04 ( -1.642590E-04 1.648724E-04) )
------------------------------------------------------------
Chi-Squared = 63.06989 using 59 PHA bins.
Reduced chi-squared = 1.106489 for 57 degrees of freedom
Null hypothesis probability = 0.270
Photon flux (15-150 keV) in 33.06 sec: 7.016895E-02 ( -0.01838 0.0184292 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.24012e-07 ( -4.08615e-08 4.50383e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.000 sec. to 33.059 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.24284 ( )
Epeak [keV] : 29.0646 ( -29.0535 8.69151 )
Norm@50keV : 9.769993E-02 ( -0.111415 0.613459 )
------------------------------------------------------------
Chi-Squared = 60.06584 using 59 PHA bins.
but latest trial 0.997401 gives Chi-Squared = 6.83609
Reduced chi-squared = 1.072604 for 56 degrees of freedom
Null hypothesis probability = 0.331
Photon flux (15-150 keV) in 33.06 sec: 6.578572E-02 ( -0.016413 0.0182629 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.7815e-08 ( -2.6123e-08 4.04254e-08 ) ergs/cm2
Band function
Time interval is from 0.000 sec. to 33.059 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.51626 ( -8.32374 0.577325 )
beta : -6.42282 ( -0.730639 7.28002 )
Epeak [keV] : 13.4519 ( -6.21385 2371.78 )
Norm@50keV : 1.884976E-03 ( -0.630336 20.9722 )
------------------------------------------------------------
Chi-Squared = 62.29927 using 59 PHA bins.
Reduced chi-squared = 1.132714 for 55 degrees of freedom
Null hypothesis probability = 0.233
Photon flux (15-150 keV) in 33.06 sec: 6.718653E-02 ( -0.0168858 0.0170116 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.84236e-08 ( -2.68576e-08 3.40743e-08 ) ergs/cm2
Plot creation:
Thu Dec 13 20:08:31 EST 2007