batgrbproduct Analysis for Trigger=450257
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 batgrbproduct analysis is using the flight position for the mask-weighting calculation.
- 4) This page will be updated for up to 10 downlinks after the trigger.
======================================================================
BAT GRB EVENT DATA PROCESSING REPORT
Process Script Ver: batgrbproduct v2.46
Process Start Time (local time): Wed Mar 30 09:59:21 EDT 2011
Host Name: gcn5
Current Working Dir: /local/data/raid16/prebascript_archive/trigger450257/GCN5_download_cron
======================================================================
Trigger: 00450257 Segment: 000
BAT Trigger Time: 323115992 [s; MET]
Trigger Stop: 323116312 [s; MET]
UTC: 2011-03-29T18:26:25.196600 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 251.176833685378 Dec: 57.5944608348539 [deg; J2000]
Catalogged Source?: YES
Point Source?: YES
GRB Indicated?: NO [ by BAT flight software ]
Image S/N Ratio: 10.73
Image Trigger?: YES
Rate S/N Ratio: 0 [ if not an image trigger ]
Image S/N Ratio: 10.73
Flight Position: [ source = BAT ]
RA: 251.176833685378 Dec: 57.5944608348539 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 251.172050206747 Dec: 57.5923576342843 [deg; J2000]
{ 16h 44m 41.3s , +57d 35' 32.5" }
+/- 2.41409580243894 [arcmin] (estimated 90% radius based on SNR)
+/- 1.08068296528027 [arcmin] (formal 1-sigma fit error)
SNR: 8.6362704850771
Angular difference between Flight and Ground position is 0.198956 arcmin
Partial Coding Fraction: 1.015625 [ 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 0.678105 0.749459 0.448817 0.134563
0.089021 0.092145 0.083207 0.076707 [error]
Peak 0.678105 0.749459 0.448817 0.134563
0.089021 0.092145 0.083207 0.076707 [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 1.72e-07 2.89e-07 3.70e-07 9.52e-07 1.09e-06 1.78e-06 erg/cm2
Error 3.59e-08 3.94e-08 7.99e-08 4.27e-07 1.87e-07 5.02e-07 erg/cm2
Peak flux Power-law 1.74e-02 1.61e-02 1.03e-02 1.02e-02 4.81e-02 5.40e-02 ph/cm2/s
Error 3.71e-03 2.21e-03 2.15e-03 4.22e-03 6.54e-03 7.75e-03 ph/cm2/s
Fluence Cutoff-PL 1.72e-07 2.90e-07 3.70e-07 9.43e-07 1.09e-06 1.77e-06 erg/cm2
Error 3.59e-08 3.94e-08 8.00e-08 4.23e-07 1.87e-07 4.98e-07 erg/cm2
Peak flux Cutoff-PL 1.74e-02 1.61e-02 1.03e-02 1.01e-02 4.81e-02 5.39e-02 ph/cm2/s
Error 3.71e-03 2.21e-03 2.15e-03 7.73e-03 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 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
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.644 0.254 - - 3.69e-04 5.79e-05 62.330 57
CPL 2.085 0.000 33.6 0.0 2.12e-04 0.00e+00 62.320 56
The chi2 of BB fit is which shows a significant improvement in the fit over a PL.
Check the BB fit.
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.644 0.254 - - 3.69e-04 5.79e-05 62.330 57
CPL 2.085 0.000 33.6 0.0 2.12e-04 0.00e+00 62.320 56
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
251.1721 +57.5924 0.0222 0.0 -160.2 1.9624 8.6 TRIG_00450257
------------------------------------------
Foreground time interval of the image:
0.000 231.690 (delta_t = 231.690 [sec])
233.000 320.000 (delta_t = 87.000 [sec])
Background time interval of the image:
Lightcurves
Notes:
- 1) All plots contain as much data as has been downloaded to date.
- 2) The mask-weighted light curves are using the flight position.
- 3) Multiple plots of different time binning/intervals are shown to cover all scenarios of short/long GRBs, rate/image triggers, and real/false positives.
- 4) 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.
- 5) 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.
- 6) 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.
- 4) For short bursts (T90<1sec), the specrtum is also fit with Blackbody, OTTB, and Double Blackbody.
Time averaged spectrum fit using the pre-slew DRM
Power-law model
Multiple GTIs in the spectrum
tstart tstop
0.000000 231.690000
233.000000 320.000000
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.64372 ( -0.250444 0.257189 )
Norm@50keV : 3.68933E-04 ( -5.86674e-05 5.70717e-05 )
------------------------------------------------------------
# Chi-Squared = 62.33 using 59 PHA bins.
# Reduced chi-squared = 1.094 for 57 degrees of freedom
# Null hypothesis probability = 2.922958e-01
Photon flux (15-150 keV) in 318.7 sec: 4.80743E-02 ( -0.00654469 0.006545 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.09423e-06 ( -1.84011e-07 1.89467e-07 ) ergs/cm2
Cutoff power-law model
Multiple GTIs in the spectrum
tstart tstop
0.000000 231.690000
233.000000 320.000000
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.08535 ( )
Epeak [keV] : 33.5694 ( )
Norm@50keV : 2.11511E-04 ( )
------------------------------------------------------------
# Chi-Squared = 62.32 using 59 PHA bins.
# Reduced chi-squared = 1.113 for 56 degrees of freedom
# Null hypothesis probability = 2.614254e-01
Photon flux (15-150 keV) in 318.7 sec: 4.80574E-02 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 1.09396e-06 ( -1.84001e-07 1.8948e-07 ) ergs/cm2
Band function
Multiple GTIs in the spectrum
tstart tstop
0.000000 231.690000
233.000000 320.000000
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 4.99120 ( -218.979 -218.979 )
beta : -1.85467 ( -0.519535 0.292742 )
Epeak [keV] : 24.4555 ( -7.98493 4.64792 )
Norm@50keV : 53.7480 ( -33.473 59.4883 )
------------------------------------------------------------
# Chi-Squared = 59.41 using 59 PHA bins.
# Reduced chi-squared = 1.080 for 55 degrees of freedom
# Null hypothesis probability = 3.182236e-01
Photon flux (15-150 keV) in 318.7 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Single BB
Spectral model blackbody:
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : ( )
R^2/D10^2 : ( )
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25
25- 50
50-150
15-150
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : ( )
Norm : ( )
------------------------------------------------------------
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25
25- 50
50-150
15-150
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : ( )
R1^2/D10^2 : ( )
kT2 [keV] : ( )
R2^2/D10^2 : ( )
------------------------------------------------------------
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25
25- 50
50-150
15-150
Peak spectrum fit
Power-law model
Time interval is from 233.000 sec. to 320.000 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.64372 ( -0.250444 0.257189 )
Norm@50keV : 3.68933E-04 ( -5.86674e-05 5.70717e-05 )
------------------------------------------------------------
# Chi-Squared = 62.33 using 59 PHA bins.
# Reduced chi-squared = 1.094 for 57 degrees of freedom
# Null hypothesis probability = 2.922958e-01
Photon flux (15-150 keV) in 318.7 sec: 4.80743E-02 ( -0.00654469 0.006545 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.09423e-06 ( -1.84011e-07 1.89467e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from 233.000 sec. to 320.000 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.08535 ( )
Epeak [keV] : 33.5694 ( )
Norm@50keV : 2.11511E-04 ( )
------------------------------------------------------------
# Chi-Squared = 62.32 using 59 PHA bins.
# Reduced chi-squared = 1.113 for 56 degrees of freedom
# Null hypothesis probability = 2.614254e-01
Photon flux (15-150 keV) in 318.7 sec: 4.80574E-02 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 1.09396e-06 ( -1.84001e-07 1.8948e-07 ) ergs/cm2
Band function
Time interval is from 233.000 sec. to 320.000 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 4.99120 ( -218.979 -218.979 )
beta : -1.85467 ( -0.519535 0.292742 )
Epeak [keV] : 24.4555 ( -7.98493 4.64792 )
Norm@50keV : 53.7480 ( -33.473 56.6365 )
------------------------------------------------------------
# Chi-Squared = 59.41 using 59 PHA bins.
# Reduced chi-squared = 1.080 for 55 degrees of freedom
# Null hypothesis probability = 3.182236e-01
Photon flux (15-150 keV) in 318.7 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Single BB
Spectral model blackbody:
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : ( )
R^2/D10^2 : ( )
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25
25- 50
50-150
15-150
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : ( )
Norm : ( )
------------------------------------------------------------
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25
25- 50
50-150
15-150
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : ( )
R1^2/D10^2 : ( )
kT2 [keV] : ( )
R2^2/D10^2 : ( )
------------------------------------------------------------
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25
25- 50
50-150
15-150
Plot creation:
Wed Mar 30 11:06:41 EDT 2011