batgrbproduct Analysis for Trigger=346250
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 v2.42
Process Start Time (local time): Thu Mar 12 10:43:28 EDT 2009
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger346250/GCN5_download_cron
======================================================================
Trigger: 00346250 Segment: 000
BAT Trigger Time: 258531424.896 [s; MET]
Trigger Stop: 258531437.056 [s; MET]
UTC: 2009-03-12T06:17:00.328140 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 282.112079698443 Dec: 36.7577737972115 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 5.73
Image Trigger?: NO
Rate S/N Ratio: 6.78232998312527 [ if not an image trigger ]
Image S/N Ratio: 5.73
Flight Position: [ source = BAT ]
RA: 282.112079698443 Dec: 36.7577737972115 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 282.110481720822 Dec: 36.7318178623095 [deg; J2000]
{ 18h 48m 26.5s , +36d 43' 54.5" }
+/- 3.46030129508471 [arcmin] (estimated 90% radius based on SNR)
+/- 1.58527650124628 [arcmin] (formal 1-sigma fit error)
SNR: 5.16363628396241
Angular difference between Flight and Ground position is 1.559250 arcmin
Partial Coding Fraction: 0.8125 [ including projection effects ]
Duration
T90: 12.1599999964237 +/-
Measured from: 0
to: 12.1599999964237 [s; relative to TRIGTIME]
T50: 12.1599999964237 +/-
Measured from: 0
to: 12.1599999964237 [s; relative to TRIGTIME]
WARNING: battblocks failed. Used TDRSS fore/background intervals
Fluence
Peak Flux (peak 12.1599999964237 second)
Measured from: 1.49011611938477e-08
to: 12.1600000113249 [s; relative to TRIGTIME]
Total Fluence
Measured from: 0
to: 12.1599999964237 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.039024 0.066245 0.055471 0.000679
0.019412 0.019212 0.016711 0.014362 [error]
Peak 0.039024 0.066245 0.055471 0.000679
0.019412 0.019212 0.016711 0.014362 [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 1.13e-08 2.45e-08 4.17e-08 1.63e-07 1.14e-07 2.39e-07 erg/cm2
Error 7.14e-09 9.15e-09 1.65e-08 1.62e-07 4.11e-08 1.70e-07 erg/cm2
Peak flux Power-law 3.00e-02 3.53e-02 2.99e-02 4.30e-02 1.11e-01 1.38e-01 ph/cm2/s
Error 1.92e-02 1.36e-02 1.15e-02 3.87e-02 3.65e-02 4.71e-02 ph/cm2/s
Fluence Cutoff-PL 1.13e-08 2.46e-08 4.17e-08 1.61e-07 1.14e-07 2.17e-07 erg/cm2
Error 7.14e-09 9.16e-09 1.65e-08 1.61e-07 4.11e-08 0.00e+00 erg/cm2
Peak flux Cutoff-PL 3.00e-02 3.53e-02 2.99e-02 4.27e-02 1.11e-01 1.38e-01 ph/cm2/s
Error 1.92e-02 1.36e-02 1.15e-02 3.85e-02 3.65e-02 4.70e-02 ph/cm2/s
Fluence Band 1.13e-08 2.45e-08 4.16e-08 1.61e-07 1.14e-07 1.83e-07 erg/cm2
Error 7.07e-09 9.12e-09 1.65e-08 1.61e-07 4.11e-08 0.00e+00 erg/cm2
Peak flux Band 3.01e-02 3.53e-02 2.99e-02 4.29e-02 1.11e-01 1.38e-01 ph/cm2/s
Error 1.54e-02 1.29e-02 1.11e-02 3.62e-02 3.54e-02 4.49e-02 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.238 0.642 - - 9.37e-04 2.99e-04 55.034 57
CPL 1.234 0.718 9979.3 5000.0 9.42e-04 3.35e-04 55.037 0
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.238 0.642 - - 9.37e-04 2.99e-04 55.034 57
CPL 1.234 0.718 9979.3 5000.0 9.42e-04 3.35e-04 55.037 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 12.160 0.000 12.160
T90 12.160 0.000 12.160
T50 12.160 0.000 12.160
Peak 12.160 0.000 12.160
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
282.1105 +36.7318 0.0373 18.9 45.2 0.2146 5.2 TRIG_00346250
------------------------------------------
Foreground time interval of the image:
0.000 12.160 (delta_t = 12.160 [sec])
Background time interval of the image:
-60.896 -32.896 (delta_t = 28.000 [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.
- 4) For short bursts (T90<1sec), the specrtum is also fit with Blackbody, OTTB, and Double Blackbody.
Time averaged spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 0.000 sec. to 12.160 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.23764 ( -0.661726 0.621331 )
Norm@50keV : 9.365281E-04 ( -2.987024E-04 2.986292E-04) )
------------------------------------------------------------
Chi-Squared = 55.03417 using 59 PHA bins.
Reduced chi-squared = 0.9655118 for 57 degrees of freedom
Null hypothesis probability = 0.549
Photon flux (15-150 keV) in 12.16 sec: 0.110549 ( -0.0364238 0.036664 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.14426e-07 ( -4.06493e-08 4.16005e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.000 sec. to 12.160 sec.
Parameters : value lower 90% higher 90%
Photon index: 1.23374 ( -0.810192 0.624943 )
Epeak [keV] : 9979.26 ( -9979.25 20.7412 )
Norm@50keV : 9.416721E-04 ( -3.012107E-04 3.687139E-04) )
------------------------------------------------------------
Chi-Squared = 55.03730 using 59 PHA bins.
but latest trial 0.423548 gives Chi-Squared = 3.74972
but latest trial 1.310386E-03 gives Chi-Squared = 4.10878
Reduced chi-squared = 0.9828089 for 56 degrees of freedom
Null hypothesis probability = 0.511
Photon flux (15-150 keV) in 12.16 sec: 0.110504 ( -0.0364098 0.036653 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.14366e-07 ( -4.05884e-08 4.16726e-08 ) ergs/cm2
Band function
Time interval is from 0.000 sec. to 12.160 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.966485 ( -9.03352 4.93113 )
beta : -1.23602 ( -8.76398 0.660533 )
Epeak [keV] : 61.5383 ( -61.4383 9938.46 )
Norm@50keV : 1.667631E-03 ( -1.667631E-03 0.558353 )
------------------------------------------------------------
Chi-Squared = 55.03410 using 59 PHA bins.
Reduced chi-squared = 1.000620 for 55 degrees of freedom
Null hypothesis probability = 0.473
Photon flux (15-150 keV) in 12.16 sec: 0.110588 ( -0.0352815 0.035507 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.14282e-07 ( -4.05828e-08 4.16454e-08 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 0.000 sec. to 12.160 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.23764 ( -0.661726 0.621331 )
Norm@50keV : 9.365281E-04 ( -2.987024E-04 2.986292E-04) )
------------------------------------------------------------
Chi-Squared = 55.03417 using 59 PHA bins.
Reduced chi-squared = 0.9655118 for 57 degrees of freedom
Null hypothesis probability = 0.549
Photon flux (15-150 keV) in 12.16 sec: 0.110549 ( -0.0364238 0.036664 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.14426e-07 ( -4.06493e-08 4.16005e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.000 sec. to 12.160 sec.
Parameters : value lower 90% higher 90%
Photon index: 1.23374 ( -0.810192 0.624943 )
Epeak [keV] : 9979.26 ( -9979.25 20.7412 )
Norm@50keV : 9.416721E-04 ( -3.012107E-04 3.687139E-04) )
------------------------------------------------------------
Chi-Squared = 55.03730 using 59 PHA bins.
but latest trial 0.423548 gives Chi-Squared = 3.74972
but latest trial 1.310386E-03 gives Chi-Squared = 4.10878
Reduced chi-squared = 0.9828089 for 56 degrees of freedom
Null hypothesis probability = 0.511
Photon flux (15-150 keV) in 12.16 sec: 0.110504 ( -0.0364098 0.036653 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.14366e-07 ( -4.05884e-08 4.16726e-08 ) ergs/cm2
Band function
Time interval is from 0.000 sec. to 12.160 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.966485 ( -9.03352 4.93113 )
beta : -1.23602 ( -8.76398 0.660533 )
Epeak [keV] : 61.5383 ( -61.4383 9938.46 )
Norm@50keV : 1.667631E-03 ( -1.667631E-03 0.558353 )
------------------------------------------------------------
Chi-Squared = 55.03410 using 59 PHA bins.
Reduced chi-squared = 1.000620 for 55 degrees of freedom
Null hypothesis probability = 0.473
Photon flux (15-150 keV) in 12.16 sec: 0.110588 ( -0.0352815 0.035507 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.14282e-07 ( -4.05828e-08 4.16454e-08 ) ergs/cm2
Plot creation:
Thu Mar 12 10:54:46 EDT 2009