batgrbproduct Analysis for Trigger=306745
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 10:06:49 EDT 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger306745/GCN5_download_cron
======================================================================
Trigger: 00306745 Segment: 000
BAT Trigger Time: 227584632 [s; MET]
Trigger Stop: 227584696 [s; MET]
UTC: 2008-03-19T01:57:09.346700 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 244.637321123988 Dec: -15.275254374716 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 18.71
Image Trigger?: YES
Rate S/N Ratio: 0 [ if not an image trigger ]
Image S/N Ratio: 18.71
Flight Position: [ source = BAT ]
RA: 244.637321123988 Dec: -15.275254374716 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 244.644298719222 Dec: -15.2806989048191 [deg; J2000]
{ 16h 18m 34.6s , -15d 16' 50.5" }
+/- 1.286362959802 [arcmin] (estimated 90% radius based on SNR)
+/- 0.597676308792213 [arcmin] (formal 1-sigma fit error)
SNR: 21.2268118782609
RA = 16h 18m 34.6s (244.644299 deg.)
Dec = -15d 16' 51" (-15.280699 deg.)
Angular difference between Flight and Ground position is 0.519439 arcmin
Partial Coding Fraction: 0.421875 [ 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 2.389056 0.254361 0.020264 0.063229
0.071750 0.062616 0.053348 0.047587 [error]
Peak 2.389056 0.254361 0.020264 0.063229
0.071750 0.062616 0.053348 0.047587 [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 8.90e-07 1.24e-07 7.78e-09 5.15e-10 1.02e-06 1.02e-06 erg/cm2
Error 1.06e-07 3.09e-08 4.72e-09 5.53e-10 1.11e-07 1.11e-07 erg/cm2
Peak flux Power-law 4.91e-01 4.01e-02 1.25e-03 4.04e-05 5.32e-01 5.32e-01 ph/cm2/s
Error 6.01e-02 9.50e-03 7.41e-04 4.97e-05 6.06e-02 6.06e-02 ph/cm2/s
Fluence Cutoff-PL 9.07e-07 9.90e-08 7.76e-10 1.52e-13 1.01e-06 1.01e-06 erg/cm2
Error 1.13e-07 4.46e-08 5.81e-09 4.96e-10 1.13e-07 1.13e-07 erg/cm2
Peak flux Cutoff-PL 4.90e-01 4.00e-02 1.25e-03 4.00e-05 5.31e-01 5.31e-01 ph/cm2/s
Error 6.00e-02 9.50e-03 7.39e-04 4.93e-05 6.05e-02 6.05e-02 ph/cm2/s
Fluence Band 8.82e-07 1.20e-07 6.71e-09 3.74e-10 1.03e-06 7.75e-07 erg/cm2
Error 1.04e-07 3.43e-08 1.11e-07 0.00e+00 0.00e+00 0.00e+00 erg/cm2
Peak flux Band 4.90e-01 4.00e-02 2.27e-04 7.75e-07 5.29e-01 5.31e-01 ph/cm2/s
Error 6.03e-02 4.13e-05 5.77e-02 6.05e-02 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 6.000 0.507 - - 1.29e-04 6.37e-05 48.088 57
CPL 1.707 0.000 1.4 5.4 4.82e-01 8.97e+02 46.921 0
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 6.000 0.507 - - 1.29e-04 6.37e-05 48.088 57
CPL 1.707 0.935 1.4 2.9 4.82e-01 0.00e+00 46.921 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
244.6443 -15.2807 0.0090 38.0 157.4 2.8460 21.2 TRIG_00306745
------------------------------------------
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: 5.99977 ( -0.497203 0.516554 )
Norm@50keV : 1.293127E-04 ( -5.177446E-05 7.567856E-05) )
------------------------------------------------------------
Chi-Squared = 48.08831 using 59 PHA bins.
Reduced chi-squared = 0.8436546 for 57 degrees of freedom
Null hypothesis probability = 0.794
Photon flux (15-150 keV) in 64.00 sec: 0.531951 ( -0.060598 0.060668 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.02257e-06 ( -1.11309e-07 1.11347e-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: 1.70704 ( )
Epeak [keV] : 1.39622 ( -0.498099 10.2494 )
Norm@50keV : 0.481971 ( -0.233015 1793.37 )
------------------------------------------------------------
Chi-Squared = 46.92144 using 59 PHA bins.
but latest trial 0.141242 gives Chi-Squared = 12.2984
but latest trial 12.3512 gives Chi-Squared = 20.7069
Reduced chi-squared = 0.8378829 for 56 degrees of freedom
Null hypothesis probability = 0.801
Photon flux (15-150 keV) in 64.00 sec: 0.531295 ( -0.060495 0.060562 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.0063e-06 ( -1.13248e-07 1.128e-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 : -9.28617 ( -0.713828 1.37194 )
beta : -5.99932 ( -0.516770 0.497142 )
Epeak [keV] : 312.873 ( -312.773 9687.13 )
Norm@50keV : 1.758097E-02 ( -7.042355E-03 1.028032E-02) )
------------------------------------------------------------
Chi-Squared = 48.08831 using 59 PHA bins.
Reduced chi-squared = 0.8743329 for 55 degrees of freedom
Null hypothesis probability = 0.734
Photon flux (15-150 keV) in 64.00 sec: 0.529391 ( -0.054552 0.060816 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.03127e-06 ( -1.11456e-07 1.11462e-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: 5.99977 ( -0.497203 0.516554 )
Norm@50keV : 1.293127E-04 ( -5.177446E-05 7.567856E-05) )
------------------------------------------------------------
Chi-Squared = 48.08831 using 59 PHA bins.
Reduced chi-squared = 0.8436546 for 57 degrees of freedom
Null hypothesis probability = 0.794
Photon flux (15-150 keV) in 64.00 sec: 0.531951 ( -0.060598 0.060668 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.02257e-06 ( -1.11309e-07 1.11347e-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: 1.70704 ( -0.976059 0.892987 )
Epeak [keV] : 1.39622 ( -0.760048 5.01637 )
Norm@50keV : 0.481971 ( )
------------------------------------------------------------
Chi-Squared = 46.92144 using 59 PHA bins.
but latest trial 0.961520 gives Chi-Squared = 4.317093E-02
but latest trial 6.41259 gives Chi-Squared = 0.520100
Reduced chi-squared = 0.8378829 for 56 degrees of freedom
Null hypothesis probability = 0.801
Photon flux (15-150 keV) in 64.00 sec: 0.531295 ( -0.060495 0.060562 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.0063e-06 ( -1.13248e-07 1.128e-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 : -9.28617 ( -0.713828 1.21878 )
beta : -5.99932 ( -0.516770 0.497142 )
Epeak [keV] : 312.873 ( -312.773 9687.13 )
Norm@50keV : 1.758097E-02 ( -7.042355E-03 1.028032E-02) )
------------------------------------------------------------
Chi-Squared = 48.08831 using 59 PHA bins.
Reduced chi-squared = 0.8743329 for 55 degrees of freedom
Null hypothesis probability = 0.734
Photon flux (15-150 keV) in 64.00 sec: 0.529391 ( -0.054552 0.060816 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.03127e-06 ( -1.11456e-07 1.11462e-07 ) ergs/cm2
Plot creation:
Wed Mar 19 10:17:32 EDT 2008