batgrbproduct Analysis for Trigger=285653
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 04:39:57 EST 2007
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger285653/GCN5_download_cron
======================================================================
Trigger: 00285653 Segment: 000
BAT Trigger Time: 206704858.432 [s; MET]
Trigger Stop: 206704859.456 [s; MET]
UTC: 2007-07-21T10:00:56.330340 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 3.17553944498637 Dec: -28.5479948098393 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 8.23
Image Trigger?: NO
Rate S/N Ratio: 10.0498756211209 [ if not an image trigger ]
Image S/N Ratio: 8.23
Flight Position: [ source = BAT ]
RA: 3.17553944498637 Dec: -28.5479948098393 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 3.14902806425596 Dec: -28.5321121793525 [deg; J2000]
{ 00h 12m 35.8s , -28d 31' 55.6" }
+/- 2.37826560411048 [arcmin] (estimated 90% radius based on SNR)
+/- 1.01267477632852 [arcmin] (formal 1-sigma fit error)
SNR: 8.82274215799201
RA = 0h 12m 35.8s (3.149028 deg.)
Dec = -28d 31' 56" (-28.532112 deg.)
Angular difference between Flight and Ground position is 1.691397 arcmin
Partial Coding Fraction: 0.7265625 [ including projection effects ]
Duration
T90: 3.87600001692772 +/- 0.776342706337866
Measured from: -0.144000023603439
to: 3.73199999332428 [s; relative to TRIGTIME]
T50: 1.97600001096725 +/- 0.875134261976284
Measured from: 0.46399998664856
to: 2.43999999761581 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 0.119999974966049
to: 1.11999997496605 [s; relative to TRIGTIME]
Total Fluence
Measured from: -0.548000007867813
to: 4.33599999547005 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.089382 0.060676 0.018739 0.013640
0.012202 0.012191 0.010534 0.008993 [error]
Peak 0.037864 0.029577 0.007243 0.001834
0.005851 0.005640 0.004785 0.004149 [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 2.61e-08 2.49e-08 1.66e-08 1.72e-08 7.46e-08 8.47e-08 erg/cm2
Error 6.16e-09 6.23e-09 8.06e-09 1.57e-08 1.99e-08 2.88e-08 erg/cm2
Peak flux Power-law 3.93e-01 2.17e-01 7.54e-02 3.42e-02 7.04e-01 7.19e-01 ph/cm2/s
Error 9.68e-02 5.07e-02 3.39e-02 2.78e-02 1.45e-01 1.50e-01 ph/cm2/s
Fluence Cutoff-PL 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 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 Cutoff-PL 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 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 Band 2.60e-08 2.77e-08 1.17e-08 6.16e-09 6.89e-08 7.19e-08 erg/cm2
Error 6.53e-09 8.13e-09 8.03e-09 9.47e-09 1.69e-08 2.58e-08 erg/cm2
Peak flux Band 3.85e-01 2.49e-01 5.51e-02 1.12e-02 7.00e-01 7.04e-01 ph/cm2/s
Error 1.11e-01 4.71e-02 2.13e-02 2.64e-02 1.45e-01 1.49e-01 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 2.588 0.451 - - 1.49e-03 5.42e-04 52.838 57
CPL 0.628 0.000 21.3 0.0 3.40e-02 0.00e+00 50.913 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 2.526 0.438 - - 3.52e-03 1.22e-03 42.191 57
CPL 0.417 0.000 22.9 0.0 1.01e-01 0.00e+00 39.928 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 4.884 -0.548 4.336
T90 3.876 -0.144 3.732
T50 1.976 0.464 2.440
Peak 1.000 0.120 1.120
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
3.1490 -28.5321 0.0220 31.9 5.6 0.2021 8.8 TRIG_00285653
------------------------------------------
Foreground time interval of the image:
-0.548 4.336 (delta_t = 4.884 [sec])
Background time interval of the image:
-77.231 -0.548 (delta_t = 76.683 [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 -0.548 sec. to 4.336 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.58816 ( -0.412070 0.489783 )
Norm@50keV : 1.489932E-03 ( -5.360853E-04 5.478868E-04) )
------------------------------------------------------------
Chi-Squared = 52.83810 using 59 PHA bins.
Reduced chi-squared = 0.9269843 for 57 degrees of freedom
Null hypothesis probability = 0.632
Photon flux (15-150 keV) in 4.884 sec: 0.309229 ( -0.063673 0.063745 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.46099e-08 ( -1.91106e-08 2.05934e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.548 sec. to 4.336 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.628011 ( )
Epeak [keV] : 21.2820 ( )
Norm@50keV : 3.400646E-02 ( )
------------------------------------------------------------
Chi-Squared = 50.91335 using 59 PHA bins.
Reduced chi-squared = 0.9091669 for 56 degrees of freedom
Null hypothesis probability = 0.667
Photon flux (15-150 keV) in 4.884 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Band function
Time interval is from -0.548 sec. to 4.336 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.42848 ( -8.64152 1.07000 )
beta : -5.61145 ( -4.37088 3.30574 )
Epeak [keV] : 16.0539 ( -15.9535 11.3805 )
Norm@50keV : 8.973949E-03 ( -1.07299 419.203 )
------------------------------------------------------------
Chi-Squared = 51.15577 using 59 PHA bins.
Reduced chi-squared = 0.9301050 for 55 degrees of freedom
Null hypothesis probability = 0.622
Photon flux (15-150 keV) in 4.884 sec: 0.307680 ( -0.063158 0.063013 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.89211e-08 ( -1.79619e-08 1.58901e-08 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 0.120 sec. to 1.120 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.52638 ( -0.403638 0.472249 )
Norm@50keV : 3.524586E-03 ( -1.214861E-03 1.228211E-03) )
------------------------------------------------------------
Chi-Squared = 42.19077 using 59 PHA bins.
Reduced chi-squared = 0.7401890 for 57 degrees of freedom
Null hypothesis probability = 0.929
Photon flux (15-150 keV) in 1.000 sec: 0.703739 ( -0.14513 0.145203 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.54758e-08 ( -8.9693e-09 9.6134e-09 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.120 sec. to 1.120 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.416729 ( )
Epeak [keV] : 22.9305 ( )
Norm@50keV : 0.101411 ( )
------------------------------------------------------------
Chi-Squared = 39.92831 using 59 PHA bins.
Reduced chi-squared = 0.7130056 for 56 degrees of freedom
Null hypothesis probability = 0.948
Photon flux (15-150 keV) in 1.000 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Band function
Time interval is from 0.120 sec. to 1.120 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.38280 ( -8.80720 3.29714 )
beta : -3.25542 ( -6.67564 1.03220 )
Epeak [keV] : 17.3868 ( -17.2698 12.8374 )
Norm@50keV : 2.081237E-02 ( -1.09600 653.190 )
------------------------------------------------------------
Chi-Squared = 40.38604 using 59 PHA bins.
Reduced chi-squared = 0.7342916 for 55 degrees of freedom
Null hypothesis probability = 0.930
Photon flux (15-150 keV) in 1.000 sec: 0.699795 ( -0.143811 0.14566 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.26454e-08 ( -7.0627e-09 1.01314e-08 ) ergs/cm2
Plot creation:
Fri Dec 14 05:04:37 EST 2007