batgrbproduct Analysis for Trigger=451794
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): Sat May 7 12:06:26 EDT 2011
Host Name: gcn5
Current Working Dir: /local/data/raid16/prebascript_archive/trigger451794/SDC
======================================================================
Trigger: 00451794 Segment: 000
BAT Trigger Time: 325032138.592 [s; MET]
Trigger Stop: 325032138.624 [s; MET]
UTC: 2011-04-20T22:42:11.716260 [includes UTCF correction]
Where From?: (*SHORT BURST*) TDRSS scaled map message
BAT
RA: 320.049201406344 Dec: -41.2645076280927 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 8.11
Image Trigger?: NO
Rate S/N Ratio: 34.1906419945575 [ if not an image trigger ]
Image S/N Ratio: 8.11
Flight Position: [ source = BAT ]
RA: 320.049201406344 Dec: -41.2645076280927 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 320.048091371453 Dec: -41.276441527799 [deg; J2000]
{ 21h 20m 11.5s , -41d 16' 35.2" }
+/- 2.22629752543174 [arcmin] (estimated 90% radius based on SNR)
+/- 0.991067325680856 [arcmin] (formal 1-sigma fit error)
SNR: 9.69551642208834
Angular difference between Flight and Ground position is 0.717782 arcmin
Partial Coding Fraction: 0.359375 [ including projection effects ]
Duration
T90: 0.0839999318122864 +/- 0.0203960609410452
Measured from: 0
to: 0.0839999318122864 [s; relative to TRIGTIME]
T50: 0.0399999022483826 +/- 0.0164924559253201
Measured from: 0.00800001621246338
to: 0.0479999184608459 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: -0.448000013828278
to: 0.551999986171722 [s; relative to TRIGTIME]
Total Fluence
Measured from: 0
to: 0.0999999642372131 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.012460 0.024721 0.042344 0.008476
0.004268 0.004458 0.005368 0.003785 [error]
Peak 0.017759 0.018450 0.047270 -0.005787
0.009580 0.009455 0.009560 0.008233 [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 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 Power-law 1.80e-01 2.08e-01 1.72e-01 2.39e-01 6.46e-01 7.98e-01 ph/cm2/s
Error 1.10e-01 8.28e-02 7.37e-02 2.06e-01 2.38e-01 3.05e-01 ph/cm2/s
Fluence Cutoff-PL 2.06e-09 1.31e-08 1.30e-08 8.13e-10 2.90e-08 2.90e-08 erg/cm2
Error 2.15e-09 3.15e-09 4.84e-09 7.81e-10 6.49e-09 6.50e-09 erg/cm2
Peak flux Cutoff-PL 2.22e-03 1.04e-01 3.27e-01 4.60e-01 0.00e+00 0.00e+00 ph/cm2/s
Error 3.10e-02 8.70e-02 1.07e-01 1.63e-01 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 3.228 0.000 - - 7.90e-03 0.00e+00 128.060 57
CPL -3.681 3.017 51.4 5.7 1.72e+01 2.23e+02 89.710 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 1.273 0.597 - - 5.44e-03 1.99e-03 74.760 57
CPL -9.802 0.000 72.1 11.0 2.91e+01 6.67e+01 67.530 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: 0.064000 sec.
T50 in the 50-300 keV band: 0.064000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 0.100 0.000 0.100
T90 0.084 0.000 0.084
T50 0.040 0.008 0.048
Peak 1.000 -0.448 0.552
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
320.0481 -41.2764 0.0199 32.4 129.3 0.0871 9.7 TRIG_00451794
------------------------------------------
Foreground time interval of the image:
0.000 0.100 (delta_t = 0.100 [sec])
Background time interval of the image:
-239.592 0.000 (delta_t = 239.592 [sec])
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
Time interval is from 0.000 sec. to 0.100 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 3.22762 ( )
Norm@50keV : 7.89663E-03 ( )
------------------------------------------------------------
# Chi-Squared = 128.06 using 59 PHA bins.
# Reduced chi-squared = 2.2467 for 57 degrees of freedom
# Null hypothesis probability = 2.209949e-07
Photon flux (15-150 keV) in 0.1 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.000 sec. to 0.100 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -3.68123 ( -3.92598 2.10822 )
Epeak [keV] : 51.3803 ( -3.89205 7.48102 )
Norm@50keV : 17.1919 ( -17.5761 427.694 )
------------------------------------------------------------
# Chi-Squared = 89.71 using 59 PHA bins.
# Reduced chi-squared = 1.602 for 56 degrees of freedom
# Null hypothesis probability = 2.837627e-03
Photon flux (15-150 keV) in 0.1 sec: 4.13211 ( -0.96727 0.98112 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.89773e-08 ( -6.4729e-09 6.5042e-09 ) ergs/cm2
Band function
Time interval is from 0.000 sec. to 0.100 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.87008 ( )
beta : -9.37167 ( )
Epeak [keV] : 5.46642 ( )
Norm@50keV : 5.31050E-02 ( )
------------------------------------------------------------
# Chi-Squared = 115.88 using 59 PHA bins.
# Reduced chi-squared = 2.1069 for 55 degrees of freedom
# Null hypothesis probability = 3.104827e-06
Photon flux (15-150 keV) in 0.1 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 -0.448 sec. to 0.552 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.27311 ( -0.576039 0.617932 )
Norm@50keV : 5.44052E-03 ( -0.00199723 0.00198934 )
------------------------------------------------------------
# Chi-Squared = 74.76 using 59 PHA bins.
# Reduced chi-squared = 1.312 for 57 degrees of freedom
# Null hypothesis probability = 5.730480e-02
Photon flux (15-150 keV) in 1 sec: 0.646024 ( -0.237235 0.238823 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.4107e-08 ( -2.15244e-08 2.22911e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.448 sec. to 0.552 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -9.80230 ( )
Epeak [keV] : 72.1050 ( -10.2618 11.6575 )
Norm@50keV : 29.0743 ( -30.4932 102.855 )
------------------------------------------------------------
# Chi-Squared = 67.53 using 59 PHA bins.
# Reduced chi-squared = 1.206 for 56 degrees of freedom
# Null hypothesis probability = 1.390834e-01
Photon flux (15-150 keV) in 1 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Band function
Time interval is from -0.448 sec. to 0.552 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 5.00000 ( -1.45226e+06 -1.45224e+06 )
beta : -9.99991 ( 33631.1 33641.1 )
Epeak [keV] : 73.3094 ( -12.8236 15.1379 )
Norm@50keV : 1.01785 ( -1.01823 2.25209 )
------------------------------------------------------------
# Chi-Squared = 68.81 using 59 PHA bins.
# Reduced chi-squared = 1.251 for 55 degrees of freedom
# Null hypothesis probability = 9.984630e-02
Photon flux (15-150 keV) in 1 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:
Sat May 7 15:13:25 EDT 2011