batgrbproduct Analysis for Trigger=261225
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): Thu Dec 13 14:24:44 EST 2007
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger261225/GCN5_download_cron
======================================================================
Trigger: 00261225 Segment: 000
BAT Trigger Time: 193591480 [s; MET]
Trigger Stop: 193591800 [s; MET]
UTC: 2007-02-19T15:24:38.225280 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 299.588800877955 Dec: 35.1930088954434 [deg; J2000]
Catalogged Source?: YES
Point Source?: YES
GRB Indicated?: NO [ by BAT flight software ]
Image S/N Ratio: 12.29
Image Trigger?: YES
Rate S/N Ratio: 0 [ if not an image trigger ]
Image S/N Ratio: 12.29
Flight Position: [ source = BAT ]
RA: 299.588800877955 Dec: 35.1930088954434 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 299.579142424733 Dec: 35.2227776289544 [deg; J2000]
{ 19h 58m 19.0s , +35d 13' 22.0" }
+/- 3.15131563255167 [arcmin] (estimated 90% radius based on SNR)
+/- 2.06061175162189 [arcmin] (formal 1-sigma fit error)
SNR: 5.90183534238608
RA = 19h 58m 19.0s (299.579142 deg.)
Dec = 35d 13' 22" (35.222778 deg.)
Angular difference between Flight and Ground position is 1.847819 arcmin
Partial Coding Fraction: 0.2304688 [ including projection effects ]
Duration
T90: 320 +/-
Measured from: 0
to: 320 [s; relative to TRIGTIME]
T50: 320 +/-
Measured from: 0
to: 320 [s; relative to TRIGTIME]
WARNING: battblocks failed. Used TDRSS fore/background intervals
Fluence
Peak Flux (peak 320 second)
Measured from: 0
to: 320 [s; relative to TRIGTIME]
Total Fluence
Measured from: 0
to: 320 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.207661 0.348657 0.341883 0.063753
0.083212 0.073960 0.061861 0.050935 [error]
Peak 0.207661 0.348657 0.341883 0.063753
0.083212 0.073960 0.061861 0.050935 [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 1.17e-07 1.86e-07 2.21e-07 5.13e-07 6.73e-07 1.04e-06 erg/cm2
Error 4.34e-08 4.30e-08 5.96e-08 2.92e-07 1.49e-07 3.39e-07 erg/cm2
Peak flux Power-law 1.15e-01 1.00e-01 5.97e-02 5.34e-02 2.98e-01 3.29e-01 ph/cm2/s
Error 4.32e-02 2.38e-02 1.56e-02 2.80e-02 7.01e-02 7.15e-02 ph/cm2/s
Fluence Cutoff-PL 8.40e-08 2.07e-07 2.52e-07 1.33e-07 6.35e-07 6.76e-07 erg/cm2
Error 5.34e-08 5.29e-08 7.58e-08 3.16e-07 1.56e-07 2.19e-07 erg/cm2
Peak flux Cutoff-PL 8.09e-02 1.09e-01 6.91e-02 1.90e-02 2.74e-01 2.78e-01 ph/cm2/s
Error 5.34e-02 2.84e-02 2.04e-02 3.24e-02 7.45e-02 8.06e-02 ph/cm2/s
Fluence Band 8.44e-08 2.06e-07 2.51e-07 1.35e-07 6.36e-07 6.78e-07 erg/cm2
Error 3.38e-08 3.93e-08 7.57e-08 2.81e-07 1.49e-07 2.13e-07 erg/cm2
Peak flux Band 8.12e-02 1.09e-01 6.91e-02 1.91e-02 2.74e-01 2.78e-01 ph/cm2/s
Error 5.02e-02 2.13e-02 1.46e-02 3.24e-02 7.39e-02 6.07e-02 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.748 0.365 - - 2.21e-03 4.81e-04 62.409 57
CPL 0.233 2.117 62.5 4977.8 1.14e-02 8.04e-02 60.111 0
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.748 0.365 - - 2.21e-03 4.81e-04 62.409 57
CPL 0.233 2.117 62.5 4977.8 1.14e-02 8.04e-02 60.111 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 320.000 0.000 320.000
T90 320.000 0.000 320.000
T50 320.000 0.000 320.000
Peak 320.000 0.000 320.000
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
299.5791 +35.2228 0.0324 51.7 -165.6 0.9285 5.9 TRIG_00261225
------------------------------------------
Foreground time interval of the image:
0.000 33.057 (delta_t = 33.057 [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 33.057 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.74793 ( -0.359328 0.371205 )
Norm@50keV : 2.206034E-03 ( -4.823143E-04 4.795631E-04) )
------------------------------------------------------------
Chi-Squared = 62.40940 using 59 PHA bins.
Reduced chi-squared = 1.094902 for 57 degrees of freedom
Null hypothesis probability = 0.290
Photon flux (15-150 keV) in 33.06 sec: 0.298071 ( -0.069519 0.070707 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.73135e-07 ( -1.49137e-07 1.49831e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.000 sec. to 33.057 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.232940 ( -2.58333 1.65057 )
Epeak [keV] : 62.4660 ( -18.1599 9937.53 )
Norm@50keV : 1.140098E-02 ( -1.140098E-02 0.149318 )
------------------------------------------------------------
Chi-Squared = 60.11085 using 59 PHA bins.
but latest trial 1.88609 gives Chi-Squared = 2.73544
Reduced chi-squared = 1.073408 for 56 degrees of freedom
Null hypothesis probability = 0.329
Photon flux (15-150 keV) in 33.06 sec: 0.274007 ( -0.073418 0.075533 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.35086e-07 ( -1.5399e-07 1.57852e-07 ) ergs/cm2
Band function
Time interval is from 0.000 sec. to 33.057 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.252511 ( -9.74749 2.34828 )
beta : -9.35689 ( -0.643113 7.74059 )
Epeak [keV] : 62.5563 ( -9.16359 9937.44 )
Norm@50keV : 1.117165E-02 ( -1.117165E-02 3.656737E-02) )
------------------------------------------------------------
Chi-Squared = 60.11125 using 59 PHA bins.
Reduced chi-squared = 1.092932 for 55 degrees of freedom
Null hypothesis probability = 0.296
Photon flux (15-150 keV) in 33.06 sec: 0.274170 ( -0.072487 0.075387 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.35641e-07 ( -1.53772e-07 1.44694e-07 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 0.000 sec. to 33.057 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.74793 ( -0.359328 0.371205 )
Norm@50keV : 2.206034E-03 ( -4.823143E-04 4.795631E-04) )
------------------------------------------------------------
Chi-Squared = 62.40940 using 59 PHA bins.
Reduced chi-squared = 1.094902 for 57 degrees of freedom
Null hypothesis probability = 0.290
Photon flux (15-150 keV) in 33.06 sec: 0.298071 ( -0.069519 0.070707 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.73135e-07 ( -1.49137e-07 1.49831e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.000 sec. to 33.057 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.232940 ( -2.58333 1.65057 )
Epeak [keV] : 62.4660 ( -18.1599 9937.53 )
Norm@50keV : 1.140098E-02 ( -1.140098E-02 0.149318 )
------------------------------------------------------------
Chi-Squared = 60.11085 using 59 PHA bins.
but latest trial 1.88609 gives Chi-Squared = 2.73544
Reduced chi-squared = 1.073408 for 56 degrees of freedom
Null hypothesis probability = 0.329
Photon flux (15-150 keV) in 33.06 sec: 0.274007 ( -0.073418 0.075533 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.35086e-07 ( -1.5399e-07 1.57852e-07 ) ergs/cm2
Band function
Time interval is from 0.000 sec. to 33.057 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.252511 ( -9.74749 2.34828 )
beta : -9.35689 ( -0.643113 7.74059 )
Epeak [keV] : 62.5563 ( -9.16359 9937.44 )
Norm@50keV : 1.117165E-02 ( -1.117165E-02 3.656737E-02) )
------------------------------------------------------------
Chi-Squared = 60.11125 using 59 PHA bins.
Reduced chi-squared = 1.092932 for 55 degrees of freedom
Null hypothesis probability = 0.296
Photon flux (15-150 keV) in 33.06 sec: 0.274170 ( -0.072487 0.075387 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.35641e-07 ( -1.53772e-07 1.44694e-07 ) ergs/cm2
Plot creation:
Thu Dec 13 14:30:33 EST 2007