batgrbproduct Analysis for Trigger=349931
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 v2.45
Process Start Time (local time): Tue Aug 11 01:06:06 EDT 2009
Host Name: gcn14
Current Working Dir: /net/raid16/BAT_GRB_process_2009/349931
======================================================================
Trigger: 00349931 Segment: 000
BAT Trigger Time: 262064121.444 [s; MET]
Trigger Stop: 262064121.508 [s; MET]
UTC: 2009-04-22T03:35:16.764880 [includes UTCF correction]
Where From?: (*SHORT BURST*) TDRSS scaled map message
BAT
RA: 294.756100929833 Dec: 40.3842290518036 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 7
Image Trigger?: NO
Rate S/N Ratio: 10.3923048454133 [ if not an image trigger ]
Image S/N Ratio: 7
Flight Position: [ source = BAT ]
RA: 294.756100929833 Dec: 40.3842290518036 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 294.743911061338 Dec: 40.3965440392835 [deg; J2000]
{ 19h 38m 58.5s , +40d 23' 47.6" }
+/- 1.88148856051605 [arcmin] (estimated 90% radius based on SNR)
+/- 0.812026030005012 [arcmin] (formal 1-sigma fit error)
SNR: 12.3302891939684
Angular difference between Flight and Ground position is 0.925360 arcmin
Partial Coding Fraction: 0.71875 [ including projection effects ]
Duration
T90: 8.47200000286102 +/- 0.381764329779977
Measured from: -0.263999998569489
to: 8.20800000429153 [s; relative to TRIGTIME]
T50: 7.47600001096725 +/- 5.53747958421237
Measured from: 0.0839999914169312
to: 7.56000000238419 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: -0.372000008821487
to: 0.627999991178513 [s; relative to TRIGTIME]
Total Fluence
Measured from: -0.392000019550323
to: 8.49599999189377 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.143956 0.127819 0.103164 0.044286
0.019264 0.019752 0.017516 0.015413 [error]
Peak 0.055026 0.073015 0.070125 0.017513
0.007169 0.007515 0.007033 0.005472 [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 3.86e-08 6.36e-08 7.95e-08 1.97e-07 2.37e-07 3.79e-07 erg/cm2
Error 8.99e-09 8.89e-09 1.82e-08 9.80e-08 4.13e-08 1.13e-07 erg/cm2
Peak flux Power-law 4.85e-01 5.51e-01 4.48e-01 6.10e-01 1.71e+00 2.09e+00 ph/cm2/s
Error 8.55e-02 6.05e-02 5.47e-02 1.52e-01 1.73e-01 2.22e-01 ph/cm2/s
Fluence Cutoff-PL 3.87e-08 6.37e-08 7.94e-08 1.95e-07 2.37e-07 3.78e-07 erg/cm2
Error 8.99e-09 8.87e-09 1.82e-08 8.78e-08 4.11e-08 1.19e-07 erg/cm2
Peak flux Cutoff-PL 4.59e-01 5.72e-01 4.62e-01 4.03e-01 1.69e+00 1.90e+00 ph/cm2/s
Error 9.87e-02 7.34e-02 6.18e-02 2.76e-01 1.77e-01 4.01e-01 ph/cm2/s
Fluence Band 3.58e-08 6.32e-08 8.12e-08 1.97e-07 2.37e-07 4.21e-07 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 4.50e-01 5.92e-01 4.47e-01 5.34e-01 1.69e+00 2.02e+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 1.679 0.289 - - 2.88e-03 4.64e-04 51.680 57
CPL 2.611 0.000 200.6 0.0 9.99e-04 0.00e+00 48.240 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 1.297 0.168 - - 1.43e-02 1.44e-03 59.110 57
CPL 0.956 0.588 153.1 0.0 2.14e-02 0.00e+00 58.320 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: 0.704000 sec.
T50 in the 50-300 keV band: 0.256000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 8.888 -0.392 8.496
T90 8.472 -0.264 8.208
T50 7.476 0.084 7.560
Peak 1.000 -0.372 0.628
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
294.7439 +40.3965 0.0157 21.4 -79.7 0.4333 12.3 TRIG_00349931
------------------------------------------
Foreground time interval of the image:
-0.392 8.496 (delta_t = 8.888 [sec])
Background time interval of the image:
-239.444 -0.392 (delta_t = 239.052 [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 -0.392 sec. to 8.496 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.67905 ( -0.282721 0.294626 )
Norm@50keV : 2.87645E-03 ( -0.00047416 0.000453749 )
------------------------------------------------------------
# Chi-Squared = 51.68 using 59 PHA bins.
# Reduced chi-squared = 0.9067 for 57 degrees of freedom
# Null hypothesis probability = 6.742092e-01
Photon flux (15-150 keV) in 8.888 sec: 0.379272 ( -0.0530381 0.0530616 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.3712e-07 ( -4.08598e-08 4.18331e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.392 sec. to 8.496 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.61128 ( )
Epeak [keV] : 200.632 ( )
Norm@50keV : 9.99429E-04 ( )
------------------------------------------------------------
# Chi-Squared = 48.24 using 59 PHA bins.
# Reduced chi-squared = 0.8614 for 56 degrees of freedom
# Null hypothesis probability = 7.600888e-01
Photon flux (15-150 keV) in 8.888 sec: 0.379231 ( -0.052759 0.052724 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.36912e-07 ( -4.06048e-08 4.16829e-08 ) ergs/cm2
Band function
Time interval is from -0.392 sec. to 8.496 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.39001 ( 1.39001 1.39001 )
beta : -1.67898 ( 1.67902 0.282731 )
Epeak [keV] : 15.0732 ( -15.085 -15.085 )
Norm@50keV : 6.73921E-03 ( -0.00673886 0.0757305 )
------------------------------------------------------------
# Chi-Squared = 51.68 using 59 PHA bins.
# Reduced chi-squared = 0.9397 for 55 degrees of freedom
# Null hypothesis probability = 6.022200e-01
Photon flux (15-150 keV) in 8.888 sec: 0.379046 ( -0.052904 0.052652 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.36909e-07 ( -3.38117e-08 3.59902e-08 ) 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 -0.372 sec. to 0.628 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.29665 ( -0.168622 0.167745 )
Norm@50keV : 1.43150E-02 ( -0.00144708 0.00144174 )
------------------------------------------------------------
# Chi-Squared = 59.11 using 59 PHA bins.
# Reduced chi-squared = 1.037 for 57 degrees of freedom
# Null hypothesis probability = 3.982661e-01
Photon flux (15-150 keV) in 1 sec: 1.70677 ( -0.17259 0.1727 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.41574e-07 ( -1.60608e-08 1.62101e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.372 sec. to 0.628 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.956034 ( -0.747892 0.42742 )
Epeak [keV] : 153.119 ( -153.173 -153.173 )
Norm@50keV : 2.13992E-02 ( )
------------------------------------------------------------
# Chi-Squared = 58.32 using 59 PHA bins.
# Reduced chi-squared = 1.041 for 56 degrees of freedom
# Null hypothesis probability = 3.901628e-01
Photon flux (15-150 keV) in 1 sec: 1.68804 ( -0.17682 0.17638 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.37885e-07 ( -1.7968e-08 1.7725e-08 ) ergs/cm2
Band function
Time interval is from -0.372 sec. to 0.628 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 4.99813 ( -1035.57 -1020.59 )
beta : -1.43931 ( -0.237156 0.210611 )
Epeak [keV] : 27.2207 ( -6.03402 5.31065 )
Norm@50keV : 795.735 ( -796.043 2752.43 )
------------------------------------------------------------
# Chi-Squared = 54.86 using 59 PHA bins.
# Reduced chi-squared = 0.9975 for 55 degrees of freedom
# Null hypothesis probability = 4.798171e-01
Photon flux (15-150 keV) in 1 sec: 1.69423 ( -0.17607 0.17642 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.3776e-07 ( -1.7947e-08 1.7731e-08 ) 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:
Fri May 27 11:53:06 EDT 2011