batgrbproduct Analysis for Trigger=306746
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 Mar 19 10:20:41 EDT 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger306746/GCN5_download_cron
======================================================================
Trigger: 00306746 Segment: 000
BAT Trigger Time: 227585792 [s; MET]
Trigger Stop: 227585856 [s; MET]
UTC: 2008-03-19T02:16:29.346660 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 83.25082142102 Dec: 22.0114726071983 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 17.69
Image Trigger?: YES
Rate S/N Ratio: 0 [ if not an image trigger ]
Image S/N Ratio: 17.69
Flight Position: [ source = BAT ]
RA: 83.25082142102 Dec: 22.0114726071983 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 83.2450895268997 Dec: 22.0085207032969 [deg; J2000]
{ 05h 32m 58.8s , +22d 00' 30.7" }
+/- 1.14091994078905 [arcmin] (estimated 90% radius based on SNR)
+/- 0.333091626797159 [arcmin] (formal 1-sigma fit error)
SNR: 25.1956333004805
RA = 5h 32m 58.8s (83.245090 deg.)
Dec = 22d 0' 31" (22.008521 deg.)
Angular difference between Flight and Ground position is 0.364738 arcmin
Partial Coding Fraction: 0.5234375 [ including projection effects ]
Duration
T90: 64 +/-
Measured from: 0
to: 64 [s; relative to TRIGTIME]
T50: 64 +/-
Measured from: 0
to: 64 [s; relative to TRIGTIME]
WARNING: battblocks failed. Used TDRSS fore/background intervals
Fluence
Peak Flux (peak 64 second)
Measured from: 0
to: 64 [s; relative to TRIGTIME]
Total Fluence
Measured from: 0
to: 64 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 1.009344 0.869821 0.488364 0.082139
0.053106 0.053145 0.046827 0.041150 [error]
Peak 1.009344 0.869821 0.488364 0.082139
0.053106 0.053145 0.046827 0.041150 [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 3.34e-07 4.07e-07 3.59e-07 5.45e-07 1.29e-06 1.65e-06 erg/cm2
Error 3.67e-08 2.87e-08 4.65e-08 1.43e-07 1.04e-07 1.91e-07 erg/cm2
Peak flux Power-law 1.71e-01 1.15e-01 5.09e-02 3.10e-02 3.52e-01 3.68e-01 ph/cm2/s
Error 1.92e-02 8.13e-03 6.34e-03 7.57e-03 2.58e-02 2.61e-02 ph/cm2/s
Fluence Cutoff-PL 3.34e-07 4.07e-07 3.59e-07 5.41e-07 1.29e-06 1.64e-06 erg/cm2
Error 3.67e-08 2.88e-08 4.66e-08 1.42e-07 1.04e-07 1.89e-07 erg/cm2
Peak flux Cutoff-PL 1.71e-01 1.15e-01 5.09e-02 3.08e-02 3.52e-01 3.68e-01 ph/cm2/s
Error 1.92e-02 8.13e-03 6.35e-03 7.52e-03 2.58e-02 2.60e-02 ph/cm2/s
Fluence Band 3.29e-07 4.08e-07 3.56e-07 5.31e-07 1.28e-06 1.63e-06 erg/cm2
Error 3.80e-08 3.30e-08 4.82e-08 2.38e-07 1.07e-07 1.59e-07 erg/cm2
Peak flux Band 1.70e-01 1.15e-01 5.08e-02 3.02e-02 3.52e-01 3.67e-01 ph/cm2/s
Error 1.96e-02 9.18e-03 6.40e-03 1.23e-02 2.67e-02 3.05e-02 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 2.181 0.150 - - 2.15e-03 1.97e-04 58.151 57
CPL 1.984 0.286 3.8 0.0 2.73e-03 1.61e-03 58.446 0
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 2.181 0.150 - - 2.15e-03 1.97e-04 58.151 57
CPL 1.984 0.207 3.8 0.0 2.73e-03 1.61e-03 58.446 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 64.000 0.000 64.000
T90 64.000 0.000 64.000
T50 64.000 0.000 64.000
Peak 64.000 0.000 64.000
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
83.2451 +22.0085 0.0077 35.5 19.0 2.5603 25.2 TRIG_00306746
------------------------------------------
Foreground time interval of the image:
0.000 64.000 (delta_t = 64.000 [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
Time interval is from 0.000 sec. to 64.000 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.18054 ( -0.147051 0.152689 )
Norm@50keV : 2.149061E-03 ( -1.985525E-04 1.945475E-04) )
------------------------------------------------------------
Chi-Squared = 58.15120 using 59 PHA bins.
Reduced chi-squared = 1.020196 for 57 degrees of freedom
Null hypothesis probability = 0.433
Photon flux (15-150 keV) in 64.00 sec: 0.352186 ( -0.025718 0.025808 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.28977e-06 ( -1.02963e-07 1.04083e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.000 sec. to 64.000 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.98382 ( -0.396635 0.174945 )
Epeak [keV] : 3.81738 ( )
Norm@50keV : 2.731620E-03 ( -1.390293E-03 1.835946E-03) )
------------------------------------------------------------
Chi-Squared = 58.44577 using 59 PHA bins.
but latest trial 2.296719E-03 gives Chi-Squared = 1.29848
Reduced chi-squared = 1.043674 for 56 degrees of freedom
Null hypothesis probability = 0.386
Photon flux (15-150 keV) in 64.00 sec: 0.352029 ( -0.025707 0.025796 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.28984e-06 ( -1.03066e-07 1.04e-07 ) ergs/cm2
Band function
Time interval is from 0.000 sec. to 64.000 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.91886 ( -8.41344 6.58656 )
beta : -9.31145 ( -0.323833 0.157315 )
Epeak [keV] : 14.7150 ( -14.7646 19.8716 )
Norm@50keV : 2.950682E-03 ( -4.323981E-02 1940.34 )
------------------------------------------------------------
Chi-Squared = 58.71667 using 59 PHA bins.
Reduced chi-squared = 1.067576 for 55 degrees of freedom
Null hypothesis probability = 0.341
Photon flux (15-150 keV) in 64.00 sec: 0.351842 ( -0.027542 0.025799 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.28269e-06 ( -1.1177e-07 1.0169e-07 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 0.000 sec. to 64.000 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.18054 ( -0.147051 0.152689 )
Norm@50keV : 2.149061E-03 ( -1.985525E-04 1.945475E-04) )
------------------------------------------------------------
Chi-Squared = 58.15120 using 59 PHA bins.
Reduced chi-squared = 1.020196 for 57 degrees of freedom
Null hypothesis probability = 0.433
Photon flux (15-150 keV) in 64.00 sec: 0.352186 ( -0.025718 0.025808 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.28977e-06 ( -1.02963e-07 1.04083e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.000 sec. to 64.000 sec.
Parameters : value lower 90% higher 90%
Photon index: 1.98382 ( -0.396635 1.814425E-02) )
Epeak [keV] : 3.81738 ( )
Norm@50keV : 2.731620E-03 ( -1.390293E-03 1.835946E-03) )
------------------------------------------------------------
Chi-Squared = 58.44577 using 59 PHA bins.
but latest trial 2.00412 gives Chi-Squared = 3.62097
but latest trial 2.296719E-03 gives Chi-Squared = 1.29848
Reduced chi-squared = 1.043674 for 56 degrees of freedom
Null hypothesis probability = 0.386
Photon flux (15-150 keV) in 64.00 sec: 0.352029 ( -0.025707 0.025796 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.28984e-06 ( -1.03066e-07 1.04e-07 ) ergs/cm2
Band function
Time interval is from 0.000 sec. to 64.000 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.91886 ( -8.41344 6.58656 )
beta : -9.31145 ( -0.323833 0.157315 )
Epeak [keV] : 14.7150 ( -14.7646 19.8716 )
Norm@50keV : 2.950682E-03 ( -4.323981E-02 1940.34 )
------------------------------------------------------------
Chi-Squared = 58.71667 using 59 PHA bins.
Reduced chi-squared = 1.067576 for 55 degrees of freedom
Null hypothesis probability = 0.341
Photon flux (15-150 keV) in 64.00 sec: 0.351842 ( -0.027542 0.025799 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.28269e-06 ( -1.1177e-07 1.0169e-07 ) ergs/cm2
Plot creation:
Wed Mar 19 10:31:31 EDT 2008