batgrbproduct Analysis for Trigger=306618
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): Tue Mar 18 06:09:46 EDT 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger306618/GCN5_download_cron
======================================================================
Trigger: 00306618 Segment: 000
BAT Trigger Time: 227491336 [s; MET]
Trigger Stop: 227491400 [s; MET]
UTC: 2008-03-18T00:02:13.349280 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 244.330859020694 Dec: -14.8818033007287 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 21.51
Image Trigger?: YES
Rate S/N Ratio: 0 [ if not an image trigger ]
Image S/N Ratio: 21.51
Flight Position: [ source = BAT ]
RA: 244.330859020694 Dec: -14.8818033007287 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 244.342549768887 Dec: -14.8945372040247 [deg; J2000]
{ 16h 17m 22.2s , -14d 53' 40.3" }
+/- 1.04314521201991 [arcmin] (estimated 90% radius based on SNR)
+/- 0.286430860704727 [arcmin] (formal 1-sigma fit error)
SNR: 28.6359481320609
RA = 16h 17m 22.2s (244.342550 deg.)
Dec = -14d 53' 40" (-14.894537 deg.)
Angular difference between Flight and Ground position is 1.021417 arcmin
Partial Coding Fraction: 1 [ 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 1.884861 0.167438 0.028212 -0.024706
0.041298 0.036431 0.031106 0.026807 [error]
Peak 1.884861 0.167438 0.028212 -0.024706
0.041298 0.036431 0.031106 0.026807 [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 5.47e-07 6.82e-08 3.69e-09 2.10e-10 6.19e-07 6.19e-07 erg/cm2
Error 6.15e-08 1.55e-08 2.07e-09 2.07e-10 6.34e-08 6.34e-08 erg/cm2
Peak flux Power-law 3.02e-01 2.21e-02 5.99e-04 1.66e-05 3.25e-01 3.25e-01 ph/cm2/s
Error 3.51e-02 4.79e-03 3.27e-04 1.93e-05 3.52e-02 3.52e-02 ph/cm2/s
Fluence Cutoff-PL 5.46e-07 6.82e-08 3.69e-09 2.09e-10 6.18e-07 6.18e-07 erg/cm2
Error 6.14e-08 1.55e-08 2.06e-09 2.05e-10 6.33e-08 6.33e-08 erg/cm2
Peak flux Cutoff-PL 3.02e-01 2.21e-02 5.97e-04 6.07e-07 3.26e-01 3.25e-01 ph/cm2/s
Error 3.51e-02 4.79e-03 3.70e-02 3.51e-02 0.00e+00 0.00e+00 ph/cm2/s
Fluence Band 5.50e-07 5.76e-08 1.84e-09 4.15e-11 6.12e-07 6.10e-07 erg/cm2
Error 6.41e-08 2.10e-08 3.97e-11 6.47e-08 6.23e-08 0.00e+00 erg/cm2
Peak flux Band 3.06e-01 1.95e-02 3.21e-04 5.38e-06 3.27e-01 3.26e-01 ph/cm2/s
Error 3.84e-02 5.34e-03 3.30e-04 7.88e-06 3.65e-02 3.70e-02 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 6.207 0.473 - - 6.41e-05 2.93e-05 51.595 57
CPL 1.622 1.943 1.7 5.5 4.54e-01 7.17e+02 49.792 0
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 6.207 0.473 - - 6.41e-05 2.93e-05 51.595 57
CPL 1.622 2.454 1.7 5.5 4.54e-01 7.17e+02 49.792 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
244.3425 -14.8945 0.0067 0.4 136.9 2.0931 28.6 TRIG_00306618
------------------------------------------
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: 6.20705 ( -0.467854 0.477490 )
Norm@50keV : 6.412189E-05 ( -2.398241E-05 3.457374E-05) )
------------------------------------------------------------
Chi-Squared = 51.59531 using 59 PHA bins.
Reduced chi-squared = 0.9051808 for 57 degrees of freedom
Null hypothesis probability = 0.677
Photon flux (15-150 keV) in 64.00 sec: 0.325108 ( -0.035199 0.035224 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.18803e-07 ( -6.33146e-08 6.34368e-08 ) 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: 1.62241 ( -1.21105 2.67493 )
Epeak [keV] : 1.65403 ( -1.64403 9.35668 )
Norm@50keV : 0.454137 ( -0.280407 1433.40 )
------------------------------------------------------------
Chi-Squared = 49.79222 using 59 PHA bins.
but latest trial 0.433478 gives Chi-Squared = 204.604
Reduced chi-squared = 0.8891469 for 56 degrees of freedom
Null hypothesis probability = 0.708
Photon flux (15-150 keV) in 64.00 sec: 0.326013 ( -0.036961 0.037078 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.18369e-07 ( -6.32621e-08 6.33594e-08 ) 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 : -9.11756 ( -0.882436 6.40761 )
beta : -6.20698 ( -0.477399 0.467858 )
Epeak [keV] : 253.466 ( -253.366 9746.53 )
Norm@50keV : 8.715499E-03 ( -3.263109E-03 4.698960E-03) )
------------------------------------------------------------
Chi-Squared = 51.59530 using 59 PHA bins.
Reduced chi-squared = 0.9380964 for 55 degrees of freedom
Null hypothesis probability = 0.606
Photon flux (15-150 keV) in 64.00 sec: 0.326736 ( -0.03629 0.036634 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.11577e-07 ( -6.50362e-08 6.4391e-08 ) 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: 6.20705 ( -0.467854 0.477490 )
Norm@50keV : 6.412189E-05 ( -2.398241E-05 3.457374E-05) )
------------------------------------------------------------
Chi-Squared = 51.59531 using 59 PHA bins.
Reduced chi-squared = 0.9051808 for 57 degrees of freedom
Null hypothesis probability = 0.677
Photon flux (15-150 keV) in 64.00 sec: 0.325108 ( -0.035199 0.035224 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.18803e-07 ( -6.33146e-08 6.34368e-08 ) 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: 1.62241 ( -1.21105 3.69668 )
Epeak [keV] : 1.65403 ( -1.64403 9.35668 )
Norm@50keV : 0.454137 ( -0.280407 1433.40 )
------------------------------------------------------------
Chi-Squared = 49.79222 using 59 PHA bins.
but latest trial 0.433478 gives Chi-Squared = 204.604
Reduced chi-squared = 0.8891469 for 56 degrees of freedom
Null hypothesis probability = 0.708
Photon flux (15-150 keV) in 64.00 sec: 0.326013 ( -0.036961 0.037078 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.18369e-07 ( -6.32621e-08 6.33594e-08 ) 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 : -9.11756 ( -0.882436 6.40761 )
beta : -6.20698 ( -0.477399 0.467858 )
Epeak [keV] : 253.466 ( -253.366 9746.53 )
Norm@50keV : 8.715499E-03 ( -3.263109E-03 4.698960E-03) )
------------------------------------------------------------
Chi-Squared = 51.59530 using 59 PHA bins.
Reduced chi-squared = 0.9380964 for 55 degrees of freedom
Null hypothesis probability = 0.606
Photon flux (15-150 keV) in 64.00 sec: 0.326736 ( -0.03629 0.036634 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.11577e-07 ( -6.50362e-08 6.4391e-08 ) ergs/cm2
Plot creation:
Tue Mar 18 06:17:55 EDT 2008