batgrbproduct Analysis for Trigger=277191
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 19:01:54 EST 2007
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger277191/GCN5_download_cron
======================================================================
Trigger: 00277191 Segment: 000
BAT Trigger Time: 199260232 [s; MET]
Trigger Stop: 199260296 [s; MET]
UTC: 2007-04-26T06:03:50.085040 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 266.861620003056 Dec: -29.993324565556 [deg; J2000]
Catalogged Source?: YES
Point Source?: YES
GRB Indicated?: NO [ by BAT flight software ]
Image S/N Ratio: 9.7
Image Trigger?: YES
Rate S/N Ratio: 0 [ if not an image trigger ]
Image S/N Ratio: 9.7
Flight Position: [ source = BAT ]
RA: 266.861620003056 Dec: -29.993324565556 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 266.903266380466 Dec: -29.9994223516097 [deg; J2000]
{ 17h 47m 36.8s , -29d 59' 57.9" }
+/- 2.59642361848449 [arcmin] (estimated 90% radius based on SNR)
+/- 1.3667621254667 [arcmin] (formal 1-sigma fit error)
SNR: 7.78311248388901
RA = 17h 47m 36.8s (266.903266 deg.)
Dec = -29d 59' 58" (-29.999422 deg.)
Angular difference between Flight and Ground position is 2.194798 arcmin
Partial Coding Fraction: 1.015625 [ 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 0.331778 0.063827 0.027966 0.013561
0.031341 0.027202 0.022734 0.019963 [error]
Peak 0.331778 0.063827 0.027966 0.013561
0.031341 0.027202 0.022734 0.019963 [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 9.59e-08 2.32e-08 2.92e-09 4.08e-10 1.22e-07 1.22e-07 erg/cm2
Error 1.80e-08 1.48e-08 4.88e-09 1.65e-09 2.97e-08 3.00e-08 erg/cm2
Peak flux Power-law 1.00e-01 1.41e-02 8.84e-04 5.88e-05 1.15e-01 1.16e-01 ph/cm2/s
Error 1.91e-02 8.47e-03 1.52e-03 2.20e-04 2.27e-02 2.27e-02 ph/cm2/s
Fluence Cutoff-PL 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 erg/cm2
Error 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 erg/cm2
Peak flux Cutoff-PL 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 ph/cm2/s
Error 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 ph/cm2/s
Fluence Band 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 erg/cm2
Error 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 erg/cm2
Peak flux Band 9.98e-02 1.56e-02 1.12e-03 8.65e-05 1.09e-01 0.00e+00 ph/cm2/s
Error 1.88e-02 4.06e-03 5.08e-04 0.00e+00 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 4.983 1.144 - - 7.61e-05 1.03e-04 48.251 57
CPL 1.812 0.000 1.0 0.0 5.88e-02 0.00e+00 50.479 0
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 4.983 1.144 - - 7.61e-05 1.03e-04 48.251 57
CPL 1.812 0.000 1.0 0.0 5.88e-02 0.00e+00 50.479 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
266.9033 -29.9994 0.0248 8.4 174.3 0.4517 7.8 TRIG_00277191
------------------------------------------
Foreground time interval of the image:
0.000 33.080 (delta_t = 33.080 [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 33.080 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 4.98275 ( -1.04432 1.24432 )
Norm@50keV : 7.612462E-05 ( -7.612463E-05 1.294802E-04) )
------------------------------------------------------------
Chi-Squared = 48.25110 using 59 PHA bins.
Reduced chi-squared = 0.8465106 for 57 degrees of freedom
Null hypothesis probability = 0.789
Photon flux (15-150 keV) in 33.08 sec: 0.115483 ( -0.0227739 0.022685 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.22331e-07 ( -2.82768e-08 3.1076e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.000 sec. to 33.080 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.81249 ( )
Epeak [keV] : 1.00564 ( )
Norm@50keV : 5.884701E-02 ( )
------------------------------------------------------------
Chi-Squared = 50.47879 using 59 PHA bins.
but latest trial 0.950053 gives Chi-Squared = 44.1859
Reduced chi-squared = 0.9014069 for 56 degrees of freedom
Null hypothesis probability = 0.683
Photon flux (15-150 keV) in 33.08 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Band function
Time interval is from 0.000 sec. to 33.080 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -8.62446 ( -1.37554 4.21118 )
beta : -4.99320 ( -1.23352 1.05359 )
Epeak [keV] : 84.5223 ( -84.4223 9915.48 )
Norm@50keV : 1.023797E-02 ( -7.529500E-03 1.770679E-02) )
------------------------------------------------------------
Chi-Squared = 48.25085 using 59 PHA bins.
Reduced chi-squared = 0.8772882 for 55 degrees of freedom
Null hypothesis probability = 0.728
Photon flux (15-150 keV) in 33.08 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 0.000 sec. to 33.080 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 4.98275 ( -1.04432 1.24432 )
Norm@50keV : 7.612462E-05 ( -7.612463E-05 1.294802E-04) )
------------------------------------------------------------
Chi-Squared = 48.25110 using 59 PHA bins.
Reduced chi-squared = 0.8465106 for 57 degrees of freedom
Null hypothesis probability = 0.789
Photon flux (15-150 keV) in 33.08 sec: 0.115483 ( -0.0227739 0.022685 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.22331e-07 ( -2.82768e-08 3.1076e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.000 sec. to 33.080 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.81249 ( )
Epeak [keV] : 1.00564 ( )
Norm@50keV : 5.884701E-02 ( )
------------------------------------------------------------
Chi-Squared = 50.47879 using 59 PHA bins.
but latest trial 0.950053 gives Chi-Squared = 44.1859
Reduced chi-squared = 0.9014069 for 56 degrees of freedom
Null hypothesis probability = 0.683
Photon flux (15-150 keV) in 33.08 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Band function
Time interval is from 0.000 sec. to 33.080 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -8.62446 ( -1.37554 4.21118 )
beta : -4.99320 ( -1.23352 1.05359 )
Epeak [keV] : 84.5223 ( -84.4223 9915.48 )
Norm@50keV : 1.023797E-02 ( -7.529500E-03 1.770679E-02) )
------------------------------------------------------------
Chi-Squared = 48.25085 using 59 PHA bins.
Reduced chi-squared = 0.8772882 for 55 degrees of freedom
Null hypothesis probability = 0.728
Photon flux (15-150 keV) in 33.08 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Plot creation:
Thu Dec 13 19:05:22 EST 2007