batgrbproduct Analysis for Trigger=345945
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): Fri Aug 21 12:27:17 EDT 2009
Host Name: gcn14
Current Working Dir: /net/raid16/BAT_GRB_process_2009/345945
======================================================================
Trigger: 00345945 Segment: 000
BAT Trigger Time: 258334157.824 [s; MET]
Trigger Stop: 258334158.848 [s; MET]
UTC: 2009-03-09T23:29:13.262340 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 284.980772926882 Dec: -25.2643001528138 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 7.07
Image Trigger?: NO
Rate S/N Ratio: 11.5758369027902 [ if not an image trigger ]
Image S/N Ratio: 7.07
Flight Position: [ source = BAT ]
RA: 284.980772926882 Dec: -25.2643001528138 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 284.98357665424 Dec: -25.2781865604214 [deg; J2000]
{ 18h 59m 56.1s , -25d 16' 41.5" }
+/- 2.27530198803213 [arcmin] (estimated 90% radius based on SNR)
+/- 0.861422836543698 [arcmin] (formal 1-sigma fit error)
SNR: 9.3985877286152
Angular difference between Flight and Ground position is 0.846958 arcmin
Partial Coding Fraction: 0.625 [ including projection effects ]
Duration
T90: 3 +/- 1.4142135623731
Measured from: -0.824000000953674
to: 2.17599999904633 [s; relative to TRIGTIME]
T50: 1 +/- 1
Measured from: 0.175999999046326
to: 1.17599999904633 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 0.175999999046326
to: 1.17599999904633 [s; relative to TRIGTIME]
Total Fluence
Measured from: -0.824000000953674
to: 2.17599999904633 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.044253 0.080126 0.062000 0.035096
0.013450 0.012652 0.011023 0.010155 [error]
Peak 0.018213 0.047891 0.029740 0.018183
0.007993 0.007700 0.006589 0.005953 [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 1.51e-08 3.13e-08 5.08e-08 1.85e-07 1.40e-07 2.82e-07 erg/cm2
Error 5.18e-09 6.21e-09 1.08e-08 9.40e-08 2.68e-08 9.99e-08 erg/cm2
Peak flux Power-law 3.16e-01 3.15e-01 2.20e-01 2.42e-01 9.47e-01 1.09e+00 ph/cm2/s
Error 1.03e-01 6.33e-02 5.39e-02 1.24e-01 1.82e-01 2.09e-01 ph/cm2/s
Fluence Cutoff-PL 1.51e-08 3.13e-08 5.08e-08 1.84e-07 1.40e-07 2.66e-07 erg/cm2
Error 5.23e-09 6.26e-09 1.09e-08 9.21e-08 2.68e-08 0.00e+00 erg/cm2
Peak flux Cutoff-PL 2.98e-01 3.25e-01 2.25e-01 1.59e-01 9.31e-01 1.00e+00 ph/cm2/s
Error 1.35e-01 8.18e-02 6.04e-02 1.90e-01 1.99e-01 2.86e-01 ph/cm2/s
Fluence Band 1.51e-08 3.13e-08 2.75e-07 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 2.83e-01 3.36e-01 2.25e-01 1.73e-01 9.18e-01 1.02e+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 1.300 0.332 - - 4.74e-03 8.12e-04 40.960 57
CPL 2.444 0.000 146.9 0.0 1.09e-03 0.00e+00 39.960 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 1.519 0.340 - - 7.54e-03 1.47e-03 75.590 57
CPL 1.150 1.766 112.4 0.0 1.17e-02 1.54e-01 75.490 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: 0.960000 sec.
T50 in the 50-300 keV band: 0.512000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 3.000 -0.824 2.176
T90 3.000 -0.824 2.176
T50 1.000 0.176 1.176
Peak 1.000 0.176 1.176
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
284.9836 -25.2782 0.0205 24.7 -93.0 0.2309 9.4 TRIG_00345945
------------------------------------------
Foreground time interval of the image:
-0.824 2.176 (delta_t = 3.000 [sec])
Background time interval of the image:
-530.623 -493.713 (delta_t = 36.910 [sec])
-239.824 -0.824 (delta_t = 239.000 [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 -0.824 sec. to 2.176 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.30047 ( -0.337112 0.327069 )
Norm@50keV : 4.73859E-03 ( -0.000812055 0.000811585 )
------------------------------------------------------------
# Chi-Squared = 40.96 using 59 PHA bins.
# Reduced chi-squared = 0.7186 for 57 degrees of freedom
# Null hypothesis probability = 9.460670e-01
Photon flux (15-150 keV) in 3 sec: 0.565370 ( -0.101421 0.102169 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.40463e-07 ( -2.65986e-08 2.69885e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.824 sec. to 2.176 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.44356 ( )
Epeak [keV] : 146.923 ( )
Norm@50keV : 1.09231E-03 ( )
------------------------------------------------------------
# Chi-Squared = 39.96 using 59 PHA bins.
# Reduced chi-squared = 0.7135 for 56 degrees of freedom
# Null hypothesis probability = 9.480817e-01
Photon flux (15-150 keV) in 3 sec: 0.565143 ( -0.101354 0.101757 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.40481e-07 ( -2.67054e-08 2.69463e-08 ) ergs/cm2
Band function
Time interval is from -0.824 sec. to 2.176 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.10958 ( 1.10962 6.07789 )
beta : -1.30040 ( 1.30043 0.3371 )
Epeak [keV] : 42.9479 ( -42.9195 -42.9195 )
Norm@50keV : 7.92095E-03 ( -0.00399451 1.12441 )
------------------------------------------------------------
# Chi-Squared = 40.96 using 59 PHA bins.
# Reduced chi-squared = 0.7448 for 55 degrees of freedom
# Null hypothesis probability = 9.204399e-01
Photon flux (15-150 keV) in 3 sec: 0.564193 ( -0.097536 0.096603 ) 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 0.176 sec. to 1.176 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.51902 ( -0.337808 0.342502 )
Norm@50keV : 7.54280E-03 ( -0.00147566 0.00145609 )
------------------------------------------------------------
# Chi-Squared = 75.59 using 59 PHA bins.
# Reduced chi-squared = 1.326 for 57 degrees of freedom
# Null hypothesis probability = 5.025745e-02
Photon flux (15-150 keV) in 1 sec: 0.946539 ( -0.181439 0.182089 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.13377e-08 ( -1.50616e-08 1.5353e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.176 sec. to 1.176 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.14952 ( -2.83799 0.694976 )
Epeak [keV] : 112.357 ( -114.538 -114.538 )
Norm@50keV : 1.16904E-02 ( -0.00664031 0.302223 )
------------------------------------------------------------
# Chi-Squared = 75.49 using 59 PHA bins.
# Reduced chi-squared = 1.348 for 56 degrees of freedom
# Null hypothesis probability = 4.232994e-02
Photon flux (15-150 keV) in 1 sec: 0.930968 ( -0.211942 0.186322 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.92185e-08 ( -1.92245e-08 1.71856e-08 ) ergs/cm2
Band function
Time interval is from 0.176 sec. to 1.176 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.526143 ( 0.872537 0.872537 )
beta : -2.01762 ( 1.83645 0.626483 )
Epeak [keV] : 68.6078 ( -70.4362 182.559 )
Norm@50keV : 2.51073E-02 ( -0.0131569 2267.82 )
------------------------------------------------------------
# Chi-Squared = 75.13 using 59 PHA bins.
# Reduced chi-squared = 1.366 for 55 degrees of freedom
# Null hypothesis probability = 3.697534e-02
Photon flux (15-150 keV) in 1 sec: 0.918496 ( -0.204238 0.193574 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.85424e-08 ( -1.59452e-08 1.66167e-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 12:10:16 EDT 2011