batgrbproduct Analysis for Trigger=293518
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): Fri Dec 14 18:07:45 EST 2007
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger293518/GCN5_download_cron
======================================================================
Trigger: 00293518 Segment: 000
BAT Trigger Time: 213529736 [s; MET]
Trigger Stop: 213529800 [s; MET]
UTC: 2007-10-08T09:48:53.723040 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 308.189666652519 Dec: 37.8034927434544 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 7.57
Image Trigger?: YES
Rate S/N Ratio: 0 [ if not an image trigger ]
Image S/N Ratio: 7.57
Flight Position: [ source = BAT ]
RA: 308.189666652519 Dec: 37.8034927434544 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 308.205468917071 Dec: 37.7614488932608 [deg; J2000]
{ 20h 32m 49.3s , +37d 45' 41.2" }
+/- 4.10092556643385 [arcmin] (estimated 90% radius based on SNR)
+/- 2.31989208429194 [arcmin] (formal 1-sigma fit error)
SNR: 4.05109872947717
RA = 20h 32m 49.3s (308.205469 deg.)
Dec = 37d 45' 41" (37.761449 deg.)
Angular difference between Flight and Ground position is 2.631577 arcmin
Partial Coding Fraction: 0.8125 [ including projection effects ]
Duration
T90: 0.0120000243186951 +/- 0.00565686571343518
Measured from: 156.115999996662
to: 156.128000020981 [s; relative to TRIGTIME]
T50: 0.00800001621246338 +/- 0.00400000810623169
Measured from: 156.115999996662
to: 156.124000012875 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 155.624000012875
to: 156.624000012875 [s; relative to TRIGTIME]
Total Fluence
Measured from: 156.115999996662
to: 156.127999991179 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.001198 0.000988 0.001881 0.001694
0.000632 0.000693 0.000634 0.000742 [error]
Peak 0.001427 0.001237 0.002122 0.001503
0.000734 0.000793 0.000714 0.000776 [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 1.66e-10 3.54e-10 5.86e-10 2.20e-09 1.61e-09 3.38e-09 erg/cm2
Error 2.01e-10 3.06e-10 4.55e-10 2.63e-09 8.14e-10 2.61e-09 erg/cm2
Peak flux Power-law 4.52e-01 4.53e-01 3.19e-01 3.56e-01 1.36e+00 1.58e+00 ph/cm2/s
Error 5.38e-01 3.88e-01 2.54e-01 4.20e-01 9.29e-01 9.43e-01 ph/cm2/s
Fluence Cutoff-PL 3.22e-11 2.98e-10 1.03e-09 8.10e-10 1.95e-09 1.93e-09 erg/cm2
Error 6.72e-11 1.63e-10 5.65e-10 1.66e-09 9.69e-10 2.48e-09 erg/cm2
Peak flux Cutoff-PL 7.29e-02 3.43e-01 5.74e-01 2.08e-01 1.16e+00 1.20e+00 ph/cm2/s
Error 3.02e-01 3.13e-01 3.69e-01 3.57e-01 6.87e-01 8.98e-01 ph/cm2/s
Fluence Band 1.49e-11 2.51e-10 1.17e-09 7.56e-10 2.03e-09 1.96e-09 erg/cm2
Error 1.44e-10 5.75e-10 5.55e-10 9.83e-10 1.19e-09 0.00e+00 erg/cm2
Peak flux Band 4.02e-02 3.09e-01 6.54e-01 1.95e-01 1.13e+00 1.19e+00 ph/cm2/s
Error 2.61e-01 3.56e-01 3.28e-01 4.75e-01 6.68e-01 0.00e+00 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.286 1.061 - - 1.36e-02 1.08e-02 48.056 57
CPL 1.280 1.070 9987.7 0.0 1.36e-02 0.00e+00 48.053 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.507 1.293 - - 1.09e-02 8.67e-03 47.456 57
CPL -2.500 0.000 87.2 3634.6 2.09e-01 3.76e-01 46.409 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 0.012 156.116 156.128
T90 0.012 156.116 156.128
T50 0.008 156.116 156.124
Peak 1.000 155.624 156.624
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
308.2055 +37.7614 0.0476 27.4 8.7 0.0056 4.1 TRIG_00293518
------------------------------------------
Foreground time interval of the image:
156.116 156.128 (delta_t = 0.012 [sec])
Background time interval of the image:
-239.000 156.116 (delta_t = 395.116 [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 156.116 sec. to 156.128 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.28631 ( -1.07144 1.05043 )
Norm@50keV : 1.357254E-02 ( -1.357254E-02 7.943419E-03) )
------------------------------------------------------------
Chi-Squared = 48.05566 using 59 PHA bins.
Reduced chi-squared = 0.8430817 for 57 degrees of freedom
Null hypothesis probability = 0.795
Photon flux (15-150 keV) in 1.2000E-02 sec: 1.61529 ( -1.03414 1.09053 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.61486e-09 ( -7.38152e-10 8.9016e-10 ) ergs/cm2
Cutoff power-law model
Time interval is from 156.116 sec. to 156.128 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.28021 ( -1.08244 1.05787 )
Epeak [keV] : 9987.66 ( )
Norm@50keV : 1.363289E-02 ( )
------------------------------------------------------------
Chi-Squared = 48.05314 using 59 PHA bins.
Reduced chi-squared = 0.8580918 for 56 degrees of freedom
Null hypothesis probability = 0.766
Photon flux (15-150 keV) in 1.2000E-02 sec: 1.48392 ( -0.776013 0.79063 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.94741e-09 ( -9.6934e-10 9.68952e-10 ) ergs/cm2
Band function
Time interval is from 156.116 sec. to 156.128 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 2.57529 ( -6.14206 4.706860E-03) )
beta : -9.31263 ( -0.628329 8.13405 )
Epeak [keV] : 97.9774 ( -38.0844 22.9462 )
Norm@50keV : 0.173831 ( -0.862304 3.72215 )
------------------------------------------------------------
Chi-Squared = 46.13380 using 59 PHA bins.
Reduced chi-squared = 0.8387964 for 55 degrees of freedom
Null hypothesis probability = 0.797
Photon flux (15-150 keV) in 1.2000E-02 sec: 1.44163 ( -0.702538 0.71918 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.03375e-09 ( -9.839e-10 9.81852e-10 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 156.116 sec. to 156.132 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.50703 ( -1.12477 1.46145 )
Norm@50keV : 1.091239E-02 ( -1.091239E-02 6.434429E-03) )
------------------------------------------------------------
Chi-Squared = 47.45571 using 59 PHA bins.
Reduced chi-squared = 0.8325562 for 57 degrees of freedom
Null hypothesis probability = 0.812
Photon flux (15-150 keV) in 1.6000E-02 sec: 1.36494 ( -0.910201 0.94712 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.65451e-09 ( -9.58902e-10 9.5864e-10 ) ergs/cm2
Cutoff power-law model
Time interval is from 156.116 sec. to 156.132 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.49993 ( )
Epeak [keV] : 87.2345 ( -86.9263 7182.25 )
Norm@50keV : 0.208907 ( -0.206915 0.545616 )
------------------------------------------------------------
Chi-Squared = 46.40862 using 59 PHA bins.
but latest trial 7269.19 gives Chi-Squared = 6.88821
Reduced chi-squared = 0.8287254 for 56 degrees of freedom
Null hypothesis probability = 0.816
Photon flux (15-150 keV) in 1.6000E-02 sec: 1.16455 ( -0.677708 0.6962 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.95442e-09 ( -1.06487e-09 1.0649e-09 ) ergs/cm2
Band function
Time interval is from 156.116 sec. to 156.132 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 3.54792 ( -14.9579 4.208469E-02) )
beta : -9.36355 ( -0.608329 8.22798 )
Epeak [keV] : 88.6763 ( -70.2132 25.9852 )
Norm@50keV : 0.330559 ( -0.931479 5.15748 )
------------------------------------------------------------
Chi-Squared = 46.16888 using 59 PHA bins.
Reduced chi-squared = 0.8394342 for 55 degrees of freedom
Null hypothesis probability = 0.796
Photon flux (15-150 keV) in 1.6000E-02 sec: 1.13485 ( -0.319997 0.62977 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.04763e-09 ( -2.04763e-09 1.05976e-09 ) ergs/cm2
Plot creation:
Fri Dec 14 18:33:04 EST 2007