batgrbproduct Analysis for Trigger=446674
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): Thu Feb 24 07:24:07 EST 2011
Host Name: gcn5
Current Working Dir: /local/data/raid16/prebascript_archive/trigger446674/SDC
======================================================================
Trigger: 00446674 Segment: 000
BAT Trigger Time: 320187425.92 [s; MET]
Trigger Stop: 320187427.968 [s; MET]
UTC: 2011-02-23T20:56:59.226720 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 345.599224203527 Dec: 87.5675078814022 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 7.37
Image Trigger?: NO
Rate S/N Ratio: 9.89949493661167 [ if not an image trigger ]
Image S/N Ratio: 7.37
Flight Position: [ source = BAT ]
RA: 345.599224203527 Dec: 87.5675078814022 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 345.386232797474 Dec: 87.5864685874389 [deg; J2000]
{ 23h 01m 32.7s , +87d 35' 11.3" }
+/- 2.51073176452441 [arcmin] (estimated 90% radius based on SNR)
+/- 1.81551558538715 [arcmin] (formal 1-sigma fit error)
SNR: 8.16535497795121
Angular difference between Flight and Ground position is 1.259415 arcmin
Partial Coding Fraction: 0.6015625 [ including projection effects ]
Duration
T90: 7 +/- 2.23606797749979
Measured from: 0.0799999833106995
to: 7.0799999833107 [s; relative to TRIGTIME]
T50: 4 +/- 2
Measured from: 0.0799999833106995
to: 4.0799999833107 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 0.0799999833106995
to: 1.0799999833107 [s; relative to TRIGTIME]
Total Fluence
Measured from: 0.0799999833106995
to: 8.0799999833107 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.088431 0.111119 0.067790 0.004303
0.018218 0.018346 0.016662 0.014840 [error]
Peak 0.023449 0.029100 0.026244 0.003676
0.006796 0.006592 0.006241 0.005518 [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 2.67e-08 4.34e-08 5.34e-08 1.30e-07 1.60e-07 2.53e-07 erg/cm2
Error 7.32e-09 8.23e-09 1.56e-08 7.65e-08 3.70e-08 9.24e-08 erg/cm2
Peak flux Power-law 2.40e-01 2.10e-01 1.26e-01 1.14e-01 6.24e-01 6.90e-01 ph/cm2/s
Error 9.11e-02 5.35e-02 4.99e-02 8.94e-02 1.59e-01 1.82e-01 ph/cm2/s
Fluence Cutoff-PL 2.38e-08 4.91e-08 5.40e-08 3.20e-08 1.48e-07 1.59e-07 erg/cm2
Error 8.44e-09 1.10e-08 1.83e-08 5.17e-08 3.84e-08 6.05e-08 erg/cm2
Peak flux Cutoff-PL 2.09e-01 2.27e-01 1.35e-01 5.26e-02 6.06e-01 6.22e-01 ph/cm2/s
Error 1.14e-01 6.55e-02 5.82e-02 2.02e-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 2.10e-01 2.26e-01 6.28e-01 0.00e+00 0.00e+00 0.00e+00 ph/cm2/s
Error 1.61e-01 1.97e-01 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 1.701 0.331 - - 2.17e-03 4.72e-04 48.390 57
CPL 0.679 1.446 58.4 -21.1 7.86e-03 3.27e-02 46.460 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 1.735 0.480 - - 4.64e-03 1.41e-03 58.130 57
CPL 0.918 1.885 65.1 0.0 1.22e-02 0.00e+00 57.480 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 8.000 0.080 8.080
T90 7.000 0.080 7.080
T50 4.000 0.080 4.080
Peak 1.000 0.080 1.080
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
345.3862 +87.5865 0.0235 23.6 66.1 0.2934 8.2 TRIG_00446674
------------------------------------------
Foreground time interval of the image:
0.080 8.080 (delta_t = 8.000 [sec])
Background time interval of the image:
-239.920 0.080 (delta_t = 240.000 [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 0.080 sec. to 8.080 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.70077 ( -0.319654 0.342726 )
Norm@50keV : 2.16540E-03 ( -0.000478964 0.000465634 )
------------------------------------------------------------
# Chi-Squared = 48.39 using 59 PHA bins.
# Reduced chi-squared = 0.8490 for 57 degrees of freedom
# Null hypothesis probability = 7.844146e-01
Photon flux (15-150 keV) in 8 sec: 0.287665 ( -0.0545465 0.0545534 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.60382e-07 ( -3.62972e-08 3.76753e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.080 sec. to 8.080 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.678573 ( -1.69304 1.19923 )
Epeak [keV] : 58.3657 ( -16.2277 -58.3497 )
Norm@50keV : 7.86011E-03 ( -0.0078741 0.0575951 )
------------------------------------------------------------
# Chi-Squared = 46.46 using 59 PHA bins.
# Reduced chi-squared = 0.8296 for 56 degrees of freedom
# Null hypothesis probability = 8.144558e-01
Photon flux (15-150 keV) in 8 sec: 0.278159 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 1.47606e-07 ( -3.66216e-08 4.02264e-08 ) ergs/cm2
Band function
Time interval is from 0.080 sec. to 8.080 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.676405 ( 1.05787 2.17242 )
beta : -10.00000 ( 4.99885e+11 4.99885e+11 )
Epeak [keV] : 58.3174 ( -18.96 -58.3174 )
Norm@50keV : 7.88058E-03 ( -0.00788064 0.0576772 )
------------------------------------------------------------
# Chi-Squared = 46.46 using 59 PHA bins.
# Reduced chi-squared = 0.8447 for 55 degrees of freedom
# Null hypothesis probability = 7.870444e-01
Photon flux (15-150 keV) in 8 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 0.080 sec. to 1.080 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.73512 ( -0.447327 0.512628 )
Norm@50keV : 4.64279E-03 ( -0.00144648 0.00136647 )
------------------------------------------------------------
# Chi-Squared = 58.13 using 59 PHA bins.
# Reduced chi-squared = 1.020 for 57 degrees of freedom
# Null hypothesis probability = 4.336093e-01
Photon flux (15-150 keV) in 1 sec: 0.624360 ( -0.158879 0.158896 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.28776e-08 ( -1.32022e-08 1.38728e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.080 sec. to 1.080 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.917758 ( -2.48532 1.28447 )
Epeak [keV] : 65.1401 ( )
Norm@50keV : 1.22155E-02 ( )
------------------------------------------------------------
# Chi-Squared = 57.48 using 59 PHA bins.
# Reduced chi-squared = 1.026 for 56 degrees of freedom
# Null hypothesis probability = 4.201600e-01
Photon flux (15-150 keV) in 1 sec: 0.605973 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 4.11279e-08 ( -1.29892e-08 1.17582e-08 ) ergs/cm2
Band function
Time interval is from 0.080 sec. to 1.080 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.923481 ( -5.53369 2.64428 )
beta : -10.00000 ( 4.46596e+11 4.46596e+11 )
Epeak [keV] : 65.4583 ( -62.5923 -65.4587 )
Norm@50keV : 1.21118E-02 ( -0.0121118 0.171422 )
------------------------------------------------------------
# Chi-Squared = 57.48 using 59 PHA bins.
# Reduced chi-squared = 1.045 for 55 degrees of freedom
# Null hypothesis probability = 3.834905e-01
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:
Thu Feb 24 07:39:49 EST 2011