batgrbproduct Analysis for Trigger=445776
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 Feb 19 00:42:50 EST 2011
Host Name: gcn5
Current Working Dir: /local/data/raid16/prebascript_archive/trigger445776/GCN5_download_cron
======================================================================
Trigger: 00445776 Segment: 000
BAT Trigger Time: 319705907.128 [s; MET]
Trigger Stop: 319705907.136 [s; MET]
UTC: 2011-02-18T07:11:40.452720 [includes UTCF correction]
Where From?: (*SHORT BURST*) TDRSS scaled map message
BAT
RA: 280.306214267364 Dec: -4.8989572973428 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 7.13
Image Trigger?: NO
Rate S/N Ratio: 18.9472953214964 [ if not an image trigger ]
Image S/N Ratio: 7.13
Flight Position: [ source = BAT ]
RA: 280.306214267364 Dec: -4.8989572973428 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 280.296077832392 Dec: -4.87386502861791 [deg; J2000]
{ 18h 41m 11.1s , -04d 52' 25.9" }
+/- 2.77655301776487 [arcmin] (estimated 90% radius based on SNR)
+/- 1.63118888184175 [arcmin] (formal 1-sigma fit error)
SNR: 7.07193763130521
Angular difference between Flight and Ground position is 1.622913 arcmin
Partial Coding Fraction: 1.015625 [ including projection effects ]
Duration
T90: 0.0079999566078186 +/- 0.00565686571343518
Measured from: 0
to: 0.0079999566078186 [s; relative to TRIGTIME]
T50: 0.0079999566078186 +/- 0.004
Measured from: 0
to: 0.0079999566078186 [s; relative to TRIGTIME]
WARNING: battblocks failed. Used TDRSS fore/background intervals
Fluence
Peak Flux (peak 0.0079999566078186 second)
Measured from: -2.98023223876953e-08
to: 0.00799992680549622 [s; relative to TRIGTIME]
Total Fluence
Measured from: 0
to: 0.0079999566078186 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.003831 0.005700 0.002350 0.000544
0.000929 0.001034 0.000796 0.000486 [error]
Peak 0.003831 0.005700 0.002350 0.000544
0.000929 0.001034 0.000796 0.000486 [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 1.13e-09 8.14e-10 3.88e-10 2.61e-10 2.46e-09 2.61e-09 erg/cm2
Error 3.84e-10 2.98e-10 2.30e-10 2.97e-10 8.46e-10 9.48e-10 erg/cm2
Peak flux Power-law 4.70e+00 1.91e+00 4.55e-01 1.32e-01 7.15e+00 7.21e+00 ph/cm2/s
Error 1.62e+00 6.84e-01 2.63e-01 1.43e-01 2.30e+00 2.32e+00 ph/cm2/s
Fluence Cutoff-PL 6.53e-10 2.91e-09 3.61e-10 4.60e-14 3.92e-09 3.93e-09 erg/cm2
Error 3.85e-10 8.03e-10 3.49e-10 1.18e-12 9.55e-10 9.58e-10 erg/cm2
Peak flux Cutoff-PL 2.43e+00 6.58e+00 5.01e-01 3.43e-05 9.50e+00 9.50e+00 ph/cm2/s
Error 1.52e+00 1.75e+00 3.75e-01 2.35e+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 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 3.063 0.523 - - 2.48e-02 1.19e-02 56.570 57
CPL -9.003 0.000 35.1 3.6 4.80e+05 0.00e+00 33.130 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 3.063 0.523 - - 2.48e-02 1.19e-02 56.570 57
CPL -9.003 0.000 35.1 3.6 4.80e+05 0.00e+00 33.130 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 0.008 0.000 0.008
T90 0.008 0.000 0.008
T50 0.008 0.000 0.008
Peak 0.008 -0.000 0.008
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
280.2961 -4.8739 0.0271 15.6 -161.1 0.0119 7.1 TRIG_00445776
------------------------------------------
Foreground time interval of the image:
0.000 0.008 (delta_t = 0.008 [sec])
Background time interval of the image:
-239.128 -3.128 (delta_t = 236.000 [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 0.008 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 3.06294 ( -0.446206 0.599848 )
Norm@50keV : 2.48381E-02 ( -0.011891 0.0118925 )
------------------------------------------------------------
# Chi-Squared = 56.57 using 59 PHA bins.
# Reduced chi-squared = 0.9924 for 57 degrees of freedom
# Null hypothesis probability = 4.912674e-01
Photon flux (15-150 keV) in 0.008 sec: 7.15325 ( -2.30061 2.30061 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.45569e-09 ( -8.3824e-10 8.53424e-10 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.000 sec. to 0.008 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -9.00325 ( )
Epeak [keV] : 35.0791 ( -3.65846 3.58473 )
Norm@50keV : 4.80455E+05 ( )
------------------------------------------------------------
# Chi-Squared = 33.13 using 59 PHA bins.
# Reduced chi-squared = 0.5915 for 56 degrees of freedom
# Null hypothesis probability = 9.936039e-01
Photon flux (15-150 keV) in 0.008 sec: 9.50277 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 3.92482e-09 ( -9.50056e-10 9.60192e-10 ) ergs/cm2
Band function
Time interval is from 0.000 sec. to 0.008 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 4.38550 ( -4.2676 2.20044 )
beta : -9.37167 ( 10 20 )
Epeak [keV] : 33.2516 ( -3.4819 4.03741 )
Norm@50keV : 1013.12 ( -1013.12 361.333 )
------------------------------------------------------------
# Chi-Squared = 35.03 using 59 PHA bins.
# Reduced chi-squared = 0.6370 for 55 degrees of freedom
# Null hypothesis probability = 9.835853e-01
Photon flux (15-150 keV) in 0.008 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 0.000 sec. to 0.008 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 3.06294 ( -0.446206 0.599848 )
Norm@50keV : 2.48381E-02 ( -0.011891 0.0118925 )
------------------------------------------------------------
# Chi-Squared = 56.57 using 59 PHA bins.
# Reduced chi-squared = 0.9924 for 57 degrees of freedom
# Null hypothesis probability = 4.912674e-01
Photon flux (15-150 keV) in 0.008 sec: 7.15325 ( -2.30061 2.30061 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.45569e-09 ( -8.3824e-10 8.53424e-10 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.000 sec. to 0.008 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -9.00325 ( )
Epeak [keV] : 35.0791 ( -3.65846 3.58473 )
Norm@50keV : 4.80455E+05 ( )
------------------------------------------------------------
# Chi-Squared = 33.13 using 59 PHA bins.
# Reduced chi-squared = 0.5915 for 56 degrees of freedom
# Null hypothesis probability = 9.936039e-01
Photon flux (15-150 keV) in 0.008 sec: 9.50277 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 3.92482e-09 ( -9.50056e-10 9.60192e-10 ) ergs/cm2
Band function
Time interval is from 0.000 sec. to 0.008 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 4.38550 ( -4.2676 2.20044 )
beta : -9.37167 ( 10 20 )
Epeak [keV] : 33.2516 ( -3.48191 4.03741 )
Norm@50keV : 1013.12 ( -1013.12 361.332 )
------------------------------------------------------------
# Chi-Squared = 35.03 using 59 PHA bins.
# Reduced chi-squared = 0.6370 for 55 degrees of freedom
# Null hypothesis probability = 9.835853e-01
Photon flux (15-150 keV) in 0.008 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 Feb 19 00:59:43 EST 2011