batgrbproduct Analysis for Trigger=273180
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 16:28:27 EST 2007
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger273180/GCN5_download_cron
======================================================================
Trigger: 00273180 Segment: 000
BAT Trigger Time: 196987893.056 [s; MET]
Trigger Stop: 196987894.08 [s; MET]
UTC: 2007-03-30T22:51:31.197500 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 269.519312152181 Dec: -63.7791777282201 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 10.25
Image Trigger?: NO
Rate S/N Ratio: 12.2065556157337 [ if not an image trigger ]
Image S/N Ratio: 10.25
Flight Position: [ source = BAT ]
RA: 269.519312152181 Dec: -63.7791777282201 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 269.556222665047 Dec: -63.8078323240761 [deg; J2000]
{ 17h 58m 13.5s , -63d 48' 28.2" }
+/- 1.71917847184396 [arcmin] (estimated 90% radius based on SNR)
+/- 0.749535107613427 [arcmin] (formal 1-sigma fit error)
SNR: 14.0263791454957
RA = 17h 58m 13.5s (269.556223 deg.)
Dec = -63d 48' 28" (-63.807832 deg.)
Angular difference between Flight and Ground position is 1.977976 arcmin
Partial Coding Fraction: 0.8046875 [ including projection effects ]
Duration
T90: 6.63999998569489 +/- 0.679764683286021
Measured from: -1.05599999427795
to: 5.58399999141693 [s; relative to TRIGTIME]
T50: 2.73599997162819 +/- 0.621327605247016
Measured from: 0.256000012159348
to: 2.99199998378754 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: -0.0279999971389771
to: 0.972000002861023 [s; relative to TRIGTIME]
Total Fluence
Measured from: -1.40799999237061
to: 5.71200001239777 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.121007 0.192170 0.056737 0.027545
0.016269 0.015111 0.012587 0.010395 [error]
Peak 0.033531 0.050491 0.016997 0.008725
0.006348 0.005958 0.004806 0.003867 [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 4.63e-08 6.33e-08 6.39e-08 1.17e-07 2.11e-07 2.90e-07 erg/cm2
Error 7.06e-09 7.03e-09 1.15e-08 4.10e-08 2.73e-08 5.43e-08 erg/cm2
Peak flux Power-law 3.74e-01 3.04e-01 1.67e-01 1.35e-01 9.06e-01 9.81e-01 ph/cm2/s
Error 8.62e-02 4.76e-02 3.87e-02 5.98e-02 1.43e-01 1.54e-01 ph/cm2/s
Fluence Cutoff-PL 4.12e-08 8.03e-08 4.56e-08 4.45e-09 1.71e-07 1.72e-07 erg/cm2
Error 8.03e-09 1.11e-08 1.94e-08 1.15e-08 2.83e-08 3.03e-08 erg/cm2
Peak flux Cutoff-PL 3.27e-01 3.60e-01 1.60e-01 2.42e-02 8.68e-01 8.71e-01 ph/cm2/s
Error 9.89e-02 7.30e-02 5.45e-02 5.85e-02 1.47e-01 1.53e-01 ph/cm2/s
Fluence Band 4.18e-08 7.66e-08 5.38e-08 5.10e-08 1.86e-07 2.27e-07 erg/cm2
Error 7.00e-09 8.80e-09 9.67e-09 2.76e-08 5.76e-08 0.00e+00 erg/cm2
Peak flux Band 3.20e-01 3.66e-01 1.55e-01 6.70e-02 8.79e-01 9.09e-01 ph/cm2/s
Error 1.34e-01 6.38e-02 4.26e-02 6.85e-02 1.41e-01 1.63e-01 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.986 0.193 - - 3.22e-03 4.33e-04 57.776 57
CPL -0.344 1.605 37.3 6.0 8.76e-02 7.65e-01 45.631 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.862 0.270 - - 6.41e-03 1.15e-03 56.843 57
CPL 0.366 1.752 44.9 30.5 4.76e-02 4.49e-01 53.395 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: 0.000000 sec.
T50 in the 50-300 keV band: 0.000000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 7.120 -1.408 5.712
T90 6.640 -1.056 5.584
T50 2.736 0.256 2.992
Peak 1.000 -0.028 0.972
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
269.5562 -63.8078 0.0137 18.6 -68.8 0.3930 14.0 TRIG_00273180
------------------------------------------
Foreground time interval of the image:
-1.408 5.712 (delta_t = 7.120 [sec])
Background time interval of the image:
-239.056 -1.408 (delta_t = 237.648 [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 -1.408 sec. to 5.712 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.98648 ( -0.189197 0.197007 )
Norm@50keV : 3.216130E-03 ( -4.358857E-04 4.298147E-04) )
------------------------------------------------------------
Chi-Squared = 57.77610 using 59 PHA bins.
Reduced chi-squared = 1.013616 for 57 degrees of freedom
Null hypothesis probability = 0.446
Photon flux (15-150 keV) in 7.120 sec: 0.479446 ( -0.053261 0.053286 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.11044e-07 ( -2.70795e-08 2.76007e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -1.408 sec. to 5.712 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.343590 ( -1.92098 1.28979 )
Epeak [keV] : 37.3076 ( -4.92640 7.01741 )
Norm@50keV : 8.760388E-02 ( -7.361760E-02 1.45592 )
------------------------------------------------------------
Chi-Squared = 45.63055 using 59 PHA bins.
Reduced chi-squared = 0.8148313 for 56 degrees of freedom
Null hypothesis probability = 0.837
Photon flux (15-150 keV) in 7.120 sec: 0.450832 ( -0.054346 0.054653 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.71102e-07 ( -2.62116e-08 3.04537e-08 ) ergs/cm2
Band function
Time interval is from -1.408 sec. to 5.712 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 0.343825 ( -2.52347 1.67618 )
beta : -2.83156 ( -0.721166 0.436476 )
Epeak [keV] : 34.9660 ( -5.45814 25.6172 )
Norm@50keV : 9.892130E-02 ( -70.2560 16.4538 )
------------------------------------------------------------
Chi-Squared = 43.70662 using 59 PHA bins.
Reduced chi-squared = 0.7946658 for 55 degrees of freedom
Null hypothesis probability = 0.863
Photon flux (15-150 keV) in 7.120 sec: 0.461726 ( -0.050809 0.054011 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.85719e-07 ( -2.51001e-08 3.01824e-08 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from -0.032 sec. to 0.976 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.86177 ( -0.263247 0.276695 )
Norm@50keV : 6.413600E-03 ( -1.163415E-03 1.138431E-03) )
------------------------------------------------------------
Chi-Squared = 56.84308 using 59 PHA bins.
Reduced chi-squared = 0.9972470 for 57 degrees of freedom
Null hypothesis probability = 0.481
Photon flux (15-150 keV) in 1.008 sec: 0.905866 ( -0.142599 0.142744 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.94245e-08 ( -1.05681e-08 1.08333e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.032 sec. to 0.976 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.365568 ( -2.12103 1.38229 )
Epeak [keV] : 44.9142 ( -10.3446 50.7231 )
Norm@50keV : 4.759896E-02 ( -3.991460E-02 0.858336 )
------------------------------------------------------------
Chi-Squared = 53.39508 using 59 PHA bins.
Reduced chi-squared = 0.9534836 for 56 degrees of freedom
Null hypothesis probability = 0.574
Photon flux (15-150 keV) in 1.008 sec: 0.867645 ( -0.146145 0.147375 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.20024e-08 ( -1.07633e-08 1.26816e-08 ) ergs/cm2
Band function
Time interval is from -0.032 sec. to 0.976 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.184545 ( -1.43434 3.67121 )
beta : -2.56539 ( -7.43461 0.739468 )
Epeak [keV] : 41.1435 ( -14.9316 29.8574 )
Norm@50keV : 6.706515E-02 ( -20.3026 128.891 )
------------------------------------------------------------
Chi-Squared = 52.68235 using 59 PHA bins.
Reduced chi-squared = 0.9578608 for 55 degrees of freedom
Null hypothesis probability = 0.564
Photon flux (15-150 keV) in 1.008 sec: 0.878600 ( -0.13863 0.14312 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.51299e-08 ( -9.87195e-09 1.17972e-08 ) ergs/cm2
Plot creation:
Thu Dec 13 16:51:22 EST 2007