batgrbproduct Analysis for Trigger=237821
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): Wed Jan 2 10:46:21 EST 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger237821/GCN5_download_cron
======================================================================
Trigger: 00237821 Segment: 000
BAT Trigger Time: 184725021.408 [s; MET]
Trigger Stop: 184725021.792 [s; MET]
UTC: 2006-11-09T00:30:19.849180 [includes UTCF correction]
Where From?: (*SHORT BURST*) Expanded to TRIGTIME - 32 ms to TRIGTIME + 320 ms
BAT
RA: 311.747439746626 Dec: 24.1665398676816 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 7.07
Image Trigger?: NO
Rate S/N Ratio: 10.295630140987 [ if not an image trigger ]
Image S/N Ratio: 7.07
Flight Position: [ source = BAT ]
RA: 311.747439746626 Dec: 24.1665398676816 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 311.976124564458 Dec: 24.0441337247238 [deg; J2000]
{ 20h 47m 54.3s , +24d 02' 38.9" }
+/- 6.33275680427346 [arcmin] (estimated 90% radius based on SNR)
+/- 4.45710122779487 [arcmin] (formal 1-sigma fit error)
SNR: 2.17763853932169
RA = 20h 47m 54.3s (311.976125 deg.)
Dec = 24d 2' 39" (24.044134 deg.)
Angular difference between Flight and Ground position is 14.519096 arcmin
Partial Coding Fraction: 0.9765625 [ including projection effects ]
Duration
T90: 0.38400000333786 +/-
Measured from: 0
to: 0.38400000333786 [s; relative to TRIGTIME]
T50: 0.38400000333786 +/-
Measured from: 0
to: 0.38400000333786 [s; relative to TRIGTIME]
WARNING: battblocks failed. Used TDRSS fore/background intervals
Fluence
Peak Flux (peak 0.38400000333786 second)
Measured from: 0
to: 0.38400000333786 [s; relative to TRIGTIME]
Total Fluence
Measured from: 0
to: 0.38400000333786 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.003737 -0.005162 0.003530 0.004842
0.003203 0.003264 0.002830 0.002575 [error]
Peak 0.003737 -0.005162 0.003530 0.004842
0.003203 0.003264 0.002830 0.002575 [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 4.80e-11 2.28e-11 1.67e-13 1.21e-15 8.74e-10 3.03e-08 erg/cm2
Error 2.95e-10 6.87e-11 2.16e-11 1.32e-09 7.55e-08 0.00e+00 erg/cm2
Peak flux Power-law 8.19e-02 1.32e-03 4.82e-06 1.76e-08 8.30e-02 8.29e-02 ph/cm2/s
Error 9.43e-02 1.50e-02 1.73e-03 2.48e-04 1.04e-01 1.04e-01 ph/cm2/s
Fluence Cutoff-PL 9.97e-10 5.05e-12 1.65e-18 1.79e-32 9.98e-10 1.03e-08 erg/cm2
Error 1.19e-09 2.64e-10 5.31e-11 1.92e+11 1.28e-09 0.00e+00 erg/cm2
Peak flux Cutoff-PL 8.15e-02 1.31e-03 4.74e-06 1.71e-08 8.27e-02 8.28e-02 ph/cm2/s
Error 9.43e-02 1.50e-02 1.73e-03 2.45e-04 1.03e-01 1.03e-01 ph/cm2/s
Fluence Band 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 Band 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
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL -0.215 0.000 - - 5.22e-04 0.00e+00 78.580 57
CPL 8.191 0.000 9992.9 4605.4 2.39e-06 1.23e-04 75.490 0
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL -0.215 0.000 - - 5.22e-04 0.00e+00 78.580 57
CPL 8.191 0.000 9992.9 4605.4 2.39e-06 1.23e-04 75.490 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 0.384 0.000 0.384
T90 0.384 0.000 0.384
T50 0.384 0.000 0.384
Peak 0.384 0.000 0.384
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
311.9761 +24.0441 0.0882 17.9 178.2 0.0131 2.2 TRIG_00237821
------------------------------------------
Foreground time interval of the image:
-0.032 0.352 (delta_t = 0.384 [sec])
Background time interval of the image:
-239.440 -146.800 (delta_t = 92.640 [sec])
-145.440 -5.440 (delta_t = 140.000 [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 -0.032 sec. to 0.352 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.215071 ( )
Norm@50keV : 5.219779E-04 ( )
------------------------------------------------------------
Chi-Squared = 78.58032 using 59 PHA bins.
Reduced chi-squared = 1.378602 for 57 degrees of freedom
Null hypothesis probability = 3.063E-02
Photon flux (15-150 keV) in 0.3840 sec: 8.300480E-02 ( -0.0682435 0.138867 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.74487e-10 ( -8.74487e-10 1.76791e-09 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.032 sec. to 0.352 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 8.19064 ( )
Epeak [keV] : 9992.90 ( -9203.67 7.09668 )
Norm@50keV : 2.394672E-06 ( -2.706318E-07 2.450192E-04) )
------------------------------------------------------------
Chi-Squared = 75.48950 using 59 PHA bins.
but latest trial 0.566597 gives Chi-Squared = 3.33121
Reduced chi-squared = 1.348027 for 56 degrees of freedom
Null hypothesis probability = 4.232E-02
Photon flux (15-150 keV) in 0.3840 sec: 8.267593E-02 ( -0.0679831 0.138952 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.97732e-10 ( -9.97732e-10 1.55341e-09 ) ergs/cm2
Band function
Time interval is from -0.032 sec. to 0.352 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -8.64350 ( )
beta : -9.04696 ( )
Epeak [keV] : 9993.78 ( )
Norm@50keV : 1.138050E-04 ( )
------------------------------------------------------------
Chi-Squared = 75.43946 using 59 PHA bins.
Reduced chi-squared = 1.371627 for 55 degrees of freedom
Null hypothesis probability = 3.507E-02
Photon flux (15-150 keV) in 0.3840 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from -0.032 sec. to 0.352 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.215071 ( )
Norm@50keV : 5.219779E-04 ( )
------------------------------------------------------------
Chi-Squared = 78.58032 using 59 PHA bins.
Reduced chi-squared = 1.378602 for 57 degrees of freedom
Null hypothesis probability = 3.063E-02
Photon flux (15-150 keV) in 0.3840 sec: 8.300480E-02 ( -0.0682435 0.138867 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.74487e-10 ( -8.74487e-10 1.76791e-09 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.032 sec. to 0.352 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 8.19064 ( )
Epeak [keV] : 9992.90 ( -9203.67 7.09668 )
Norm@50keV : 2.394672E-06 ( -2.706318E-07 2.450192E-04) )
------------------------------------------------------------
Chi-Squared = 75.48950 using 59 PHA bins.
but latest trial 0.566597 gives Chi-Squared = 3.33121
Reduced chi-squared = 1.348027 for 56 degrees of freedom
Null hypothesis probability = 4.232E-02
Photon flux (15-150 keV) in 0.3840 sec: 8.267593E-02 ( -0.0679831 0.138952 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.97732e-10 ( -9.97732e-10 1.55341e-09 ) ergs/cm2
Band function
Time interval is from -0.032 sec. to 0.352 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -8.64350 ( )
beta : -9.04696 ( )
Epeak [keV] : 9993.78 ( )
Norm@50keV : 1.138050E-04 ( )
------------------------------------------------------------
Chi-Squared = 75.43946 using 59 PHA bins.
Reduced chi-squared = 1.371627 for 55 degrees of freedom
Null hypothesis probability = 3.507E-02
Photon flux (15-150 keV) in 0.3840 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Plot creation:
Wed Jan 2 11:19:37 EST 2008