batgrbproduct Analysis for Trigger=176702
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): Sat Dec 29 18:58:29 EST 2007
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger176702/SDC
======================================================================
Trigger: 00176702 Segment: 000
BAT Trigger Time: 158572878.72 [s; MET]
Trigger Stop: 158572879.232 [s; MET]
UTC: 2006-01-10T08:01:17.773060 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 72.740721621106 Dec: 28.3800293891184 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 7.92
Image Trigger?: NO
Rate S/N Ratio: 18.5202591774521 [ if not an image trigger ]
Image S/N Ratio: 7.92
Flight Position: [ source = BAT ]
RA: 72.740721621106 Dec: 28.3800293891184 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 72.7378753849875 Dec: 28.4276505806565 [deg; J2000]
{ 04h 50m 57.1s , +28d 25' 39.5" }
+/- 0.780580809320177 [arcmin] (estimated 90% radius based on SNR)
+/- 0.235075425886241 [arcmin] (formal 1-sigma fit error)
SNR: 43.3318406398017
RA = 4h 50m 57.1s (72.737875 deg.)
Dec = 28d 25' 40" (28.427651 deg.)
Angular difference between Flight and Ground position is 2.861217 arcmin
Partial Coding Fraction: 0.921875 [ including projection effects ]
Duration
T90: 25 +/- 4.12310562561766
Measured from: 0.280000001192093
to: 25.2800000011921 [s; relative to TRIGTIME]
T50: 9 +/- 1
Measured from: 2.28000000119209
to: 11.2800000011921 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 1.28000000119209
to: 2.28000000119209 [s; relative to TRIGTIME]
Total Fluence
Measured from: -1.71999999880791
to: 34.2800000011921 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.847035 0.928844 0.684228 0.139463
0.032160 0.032793 0.028563 0.023466 [error]
Peak 0.058067 0.089357 0.073575 0.007065
0.006021 0.006322 0.005825 0.004523 [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 2.45e-07 4.11e-07 5.23e-07 1.33e-06 1.55e-06 2.52e-06 erg/cm2
Error 1.99e-08 1.88e-08 2.92e-08 1.70e-07 6.86e-08 1.87e-07 erg/cm2
Peak flux Power-law 5.84e-01 6.35e-01 4.91e-01 6.22e-01 1.94e+00 2.33e+00 ph/cm2/s
Error 8.12e-02 5.49e-02 4.64e-02 1.20e-01 1.56e-01 1.87e-01 ph/cm2/s
Fluence Cutoff-PL 2.44e-07 4.13e-07 5.25e-07 1.23e-06 1.54e-06 2.35e-06 erg/cm2
Error 2.12e-08 1.99e-08 3.10e-08 3.28e-07 5.54e-08 3.45e-07 erg/cm2
Peak flux Cutoff-PL 4.99e-01 6.84e-01 5.29e-01 2.78e-01 1.89e+00 1.99e+00 ph/cm2/s
Error 9.77e-02 6.67e-02 5.58e-02 1.52e-01 1.61e-01 2.17e-01 ph/cm2/s
Fluence Band 2.39e-07 4.10e-07 5.22e-07 1.32e-06 1.55e-06 2.38e-06 erg/cm2
Error 2.30e-08 1.98e-08 3.07e-08 1.69e-07 6.81e-08 2.37e-07 erg/cm2
Peak flux Band 4.99e-01 6.84e-01 5.29e-01 2.78e-01 1.89e+00 1.99e+00 ph/cm2/s
Error 9.77e-02 6.67e-02 5.58e-02 1.52e-01 1.61e-01 2.17e-01 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.653 0.083 - - 4.63e-03 1.94e-04 49.544 57
CPL 1.601 0.209 412.1 0.0 4.89e-03 1.95e-04 49.581 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.372 0.131 - - 1.61e-02 1.26e-03 53.145 57
CPL 0.538 0.605 90.0 48.6 4.16e-02 3.15e-02 46.253 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: 22.528000 sec.
T50 in the 50-300 keV band: 8.384000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 36.000 -1.720 34.280
T90 25.000 0.280 25.280
T50 9.000 2.280 11.280
Peak 1.000 1.280 2.280
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
72.7379 +28.4277 0.0044 24.1 -177.5 2.8247 43.3 TRIG_00176702
------------------------------------------
Foreground time interval of the image:
-1.720 34.280 (delta_t = 36.000 [sec])
Background time interval of the image:
-299.720 -20.391 (delta_t = 279.329 [sec])
-19.720 -1.720 (delta_t = 18.000 [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 -1.720 sec. to 34.280 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.65287 ( -8.246851E-02 8.300734E-02) )
Norm@50keV : 4.625744E-03 ( -1.947186E-04 1.942567E-04) )
------------------------------------------------------------
Chi-Squared = 49.54436 using 59 PHA bins.
Reduced chi-squared = 0.8691994 for 57 degrees of freedom
Null hypothesis probability = 0.748
Photon flux (15-150 keV) in 36.00 sec: 0.604581 ( -0.027521 0.027649 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.54835e-06 ( -6.84144e-08 6.88104e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -1.720 sec. to 34.280 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.60129 ( -0.283842 0.133849 )
Epeak [keV] : 412.139 ( )
Norm@50keV : 4.888154E-03 ( -1.968876E-04 1.935461E-04) )
------------------------------------------------------------
Chi-Squared = 49.58107 using 59 PHA bins.
Reduced chi-squared = 0.8853762 for 56 degrees of freedom
Null hypothesis probability = 0.715
Photon flux (15-150 keV) in 36.00 sec: 0.604256 ( -0.027505 0.027634 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.54322e-06 ( -3.62916e-08 7.45704e-08 ) ergs/cm2
Band function
Time interval is from -1.720 sec. to 34.280 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.41932 ( -8.58068 4.33107 )
beta : -1.65287 ( -8.301926E-02 8.250427E-02) )
Epeak [keV] : 23.5286 ( -23.4286 9976.47 )
Norm@50keV : 8.618905E-03 ( -3.992009E-03 26.9795 )
------------------------------------------------------------
Chi-Squared = 49.54436 using 59 PHA bins.
Reduced chi-squared = 0.9008065 for 55 degrees of freedom
Null hypothesis probability = 0.682
Photon flux (15-150 keV) in 36.00 sec: 0.604225 ( -0.031008 0.027666 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.54683e-06 ( -6.74676e-08 6.87996e-08 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 1.280 sec. to 2.280 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.37164 ( -0.131333 0.131176 )
Norm@50keV : 1.605721E-02 ( -1.262809E-03 1.261400E-03) )
------------------------------------------------------------
Chi-Squared = 53.14547 using 59 PHA bins.
Reduced chi-squared = 0.9323767 for 57 degrees of freedom
Null hypothesis probability = 0.620
Photon flux (15-150 keV) in 1.000 sec: 1.94325 ( -0.1554 0.15562 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.56148e-07 ( -1.3567e-08 1.3532e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 1.280 sec. to 2.280 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.537555 ( -0.649179 0.560665 )
Epeak [keV] : 90.0428 ( -20.0185 77.2561 )
Norm@50keV : 4.159649E-02 ( -1.929379E-02 4.374585E-02) )
------------------------------------------------------------
Chi-Squared = 46.25278 using 59 PHA bins.
Reduced chi-squared = 0.8259425 for 56 degrees of freedom
Null hypothesis probability = 0.820
Photon flux (15-150 keV) in 1.000 sec: 1.88694 ( -0.16076 0.16043 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.48335e-07 ( -1.465e-08 1.4911e-08 ) ergs/cm2
Band function
Time interval is from 1.280 sec. to 2.280 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.537919 ( -0.560286 0.649702 )
beta : -8.97897 ( -1.02103 7.50050 )
Epeak [keV] : 90.0615 ( -20.0742 76.8046 )
Norm@50keV : 4.157408E-02 ( -1.926957E-02 4.379903E-02) )
------------------------------------------------------------
Chi-Squared = 46.25278 using 59 PHA bins.
Reduced chi-squared = 0.8409597 for 55 degrees of freedom
Null hypothesis probability = 0.793
Photon flux (15-150 keV) in 1.000 sec: 1.88688 ( -0.16074 0.16057 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.4836e-07 ( -1.475e-08 1.4768e-08 ) ergs/cm2
Plot creation:
Sat Dec 29 19:12:45 EST 2007