batgrbproduct Analysis for Trigger=221873
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): Tue Jan 1 22:16:33 EST 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger221873/GCN5_download_cron
======================================================================
Trigger: 00221873 Segment: 000
BAT Trigger Time: 175968240 [s; MET]
Trigger Stop: 175968576 [s; MET]
UTC: 2006-07-30T16:03:58.650640 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 75.8093048773688 Dec: -29.9051313280818 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: NO [ by BAT flight software ]
Image S/N Ratio: 7.55
Image Trigger?: YES
Rate S/N Ratio: 0 [ if not an image trigger ]
Image S/N Ratio: 7.55
Flight Position: [ source = BAT ]
RA: 75.8093048773688 Dec: -29.9051313280818 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 75.9133610300726 Dec: -29.8101744783869 [deg; J2000]
{ 05h 03m 39.2s , -29d 48' 36.6" }
+/- 4.49385422257209 [arcmin] (estimated 90% radius based on SNR)
+/- 2.87768368939204 [arcmin] (formal 1-sigma fit error)
SNR: 3.55472125703659
RA = 5h 3m 39.2s (75.913361 deg.)
Dec = -29d 48' 37" (-29.810174 deg.)
Angular difference between Flight and Ground position is 7.859960 arcmin
Partial Coding Fraction: 0.734375 [ including projection effects ]
Duration
T90: 336 +/-
Measured from: 0
to: 336 [s; relative to TRIGTIME]
T50: 336 +/-
Measured from: 0
to: 336 [s; relative to TRIGTIME]
WARNING: battblocks failed. Used TDRSS fore/background intervals
Fluence
Peak Flux (peak 336 second)
Measured from: 0
to: 336 [s; relative to TRIGTIME]
Total Fluence
Measured from: 0
to: 336 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.496251 0.553382 0.073450 -0.104816
0.104181 0.104217 0.093317 0.088204 [error]
Peak 0.496251 0.553382 0.073450 -0.104816
0.104181 0.104217 0.093317 0.088204 [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 1.81e-07 1.96e-07 1.51e-07 1.91e-07 6.00e-07 7.21e-07 erg/cm2
Error 5.25e-08 5.33e-08 7.82e-08 2.21e-07 1.86e-07 3.03e-07 erg/cm2
Peak flux Power-law 1.78e-02 1.07e-02 4.13e-03 2.13e-03 3.38e-02 3.48e-02 ph/cm2/s
Error 5.26e-03 2.83e-03 2.07e-03 2.33e-03 8.09e-03 8.48e-03 ph/cm2/s
Fluence Cutoff-PL 1.72e-07 2.27e-07 1.26e-07 2.46e-08 5.46e-07 5.50e-07 erg/cm2
Error 5.90e-08 7.51e-08 9.22e-08 1.86e-07 1.82e-07 2.97e-07 erg/cm2
Peak flux Cutoff-PL 1.67e-02 1.24e-02 3.59e-03 3.74e-04 3.30e-02 3.31e-02 ph/cm2/s
Error 5.97e-03 3.99e-03 3.08e-03 1.98e-03 8.06e-03 8.17e-03 ph/cm2/s
Fluence Band 1.71e-07 2.26e-07 1.26e-07 2.56e-08 5.46e-07 5.50e-07 erg/cm2
Error 4.82e-08 4.51e-08 4.30e-08 1.73e-07 1.50e-07 2.37e-07 erg/cm2
Peak flux Band 1.68e-02 1.23e-02 3.63e-03 4.11e-04 3.31e-02 3.31e-02 ph/cm2/s
Error 4.57e-03 2.97e-03 3.08e-03 1.42e-03 6.06e-03 6.18e-03 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 2.376 0.509 - - 1.85e-04 7.11e-05 58.810 57
CPL 1.146 1.929 25.4 22.8 1.10e-03 4.84e-02 57.745 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 2.376 0.509 - - 1.85e-04 7.11e-05 58.810 57
CPL 1.146 1.910 25.4 22.8 1.10e-03 4.84e-02 57.745 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 336.000 0.000 336.000
T90 336.000 0.000 336.000
T50 336.000 0.000 336.000
Peak 336.000 0.000 336.000
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
75.9134 -29.8102 0.0542 35.0 -161.0 0.8756 3.6 TRIG_00221873
------------------------------------------
Foreground time interval of the image:
0.000 311.370 (delta_t = 311.370 [sec])
313.000 336.000 (delta_t = 23.000 [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
0.000000 311.370000
313.000000 336.000000
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.37550 ( -0.459117 0.559517 )
Norm@50keV : 1.850582E-04 ( -7.170217E-05 7.053337E-05) )
------------------------------------------------------------
Chi-Squared = 58.81020 using 59 PHA bins.
Reduced chi-squared = 1.031758 for 57 degrees of freedom
Null hypothesis probability = 0.409
Photon flux (15-150 keV) in 334.4 sec: 3.375722E-02 ( -0.00808383 0.00808829 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.00355e-07 ( -1.787e-07 1.9243e-07 ) ergs/cm2
Cutoff power-law model
Multiple GTIs in the spectrum
tstart tstop
0.000000 311.370000
313.000000 336.000000
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.14625 ( -3.09503 0.762296 )
Epeak [keV] : 25.3629 ( -25.3529 20.2351 )
Norm@50keV : 1.099749E-03 ( -1.099749E-03 9.576701E-02) )
------------------------------------------------------------
Chi-Squared = 57.74467 using 59 PHA bins.
Reduced chi-squared = 1.031155 for 56 degrees of freedom
Null hypothesis probability = 0.411
Photon flux (15-150 keV) in 334.4 sec: 3.303041E-02 ( -0.0080233 0.00809817 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.45888e-07 ( -1.59713e-07 2.0481e-07 ) ergs/cm2
Band function
Multiple GTIs in the spectrum
tstart tstop
0.000000 311.370000
313.000000 336.000000
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.47177 ( -8.52823 1.37613 )
beta : -9.24226 ( -0.757742 7.23278 )
Epeak [keV] : 21.5428 ( -21.4428 46.1711 )
Norm@50keV : 6.859490E-04 ( -6.859490E-04 0.106215 )
------------------------------------------------------------
Chi-Squared = 57.81918 using 59 PHA bins.
Reduced chi-squared = 1.051258 for 55 degrees of freedom
Null hypothesis probability = 0.372
Photon flux (15-150 keV) in 334.4 sec: 3.310127E-02 ( -0.00804016 0.00407141 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.46293e-07 ( -1.38067e-07 1.62358e-07 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 313.000 sec. to 336.000 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.37550 ( -0.459117 0.559517 )
Norm@50keV : 1.850582E-04 ( -7.170217E-05 7.053337E-05) )
------------------------------------------------------------
Chi-Squared = 58.81020 using 59 PHA bins.
Reduced chi-squared = 1.031758 for 57 degrees of freedom
Null hypothesis probability = 0.409
Photon flux (15-150 keV) in 334.4 sec: 3.375722E-02 ( -0.00808383 0.00808829 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.00355e-07 ( -1.787e-07 1.9243e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from 313.000 sec. to 336.000 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.14625 ( -3.09503 0.724023 )
Epeak [keV] : 25.3629 ( -25.3529 20.2351 )
Norm@50keV : 1.099749E-03 ( -1.099749E-03 9.576701E-02) )
------------------------------------------------------------
Chi-Squared = 57.74467 using 59 PHA bins.
but latest trial 2.01391 gives Chi-Squared = 2.78947
Reduced chi-squared = 1.031155 for 56 degrees of freedom
Null hypothesis probability = 0.411
Photon flux (15-150 keV) in 334.4 sec: 3.303041E-02 ( -0.0080233 0.00809817 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.45888e-07 ( -1.59713e-07 2.0481e-07 ) ergs/cm2
Band function
Time interval is from 313.000 sec. to 336.000 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.47177 ( -8.52823 1.37613 )
beta : -9.24226 ( -0.757742 7.23365 )
Epeak [keV] : 21.5428 ( -21.4428 46.1711 )
Norm@50keV : 6.859490E-04 ( -6.859490E-04 0.106215 )
------------------------------------------------------------
Chi-Squared = 57.81918 using 59 PHA bins.
Reduced chi-squared = 1.051258 for 55 degrees of freedom
Null hypothesis probability = 0.372
Photon flux (15-150 keV) in 334.4 sec: 3.310127E-02 ( -0.00804016 0.00407141 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.46293e-07 ( -1.38067e-07 1.62358e-07 ) ergs/cm2
Plot creation:
Tue Jan 1 22:37:33 EST 2008