batgrbproduct Analysis for Trigger=420256
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 page will be updated for up to 8 downlinks after the trigger.
======================================================================
BAT GRB EVENT DATA PROCESSING REPORT
Process Script Ver: batgrbproduct v2.45
Process Start Time (local time): Sat Apr 24 07:28:08 EDT 2010
Host Name: gcn5
Current Working Dir: /local/data/raid16/prebascript_archive/trigger420256/GCN5_download_cron
======================================================================
Trigger: 00420256 Segment: 000
BAT Trigger Time: 293683448 [s; MET]
Trigger Stop: 293683512 [s; MET]
UTC: 2010-04-23T02:44:02.267960 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 271.841486050591 Dec: 27.1718850726204 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 7.02
Image Trigger?: YES
Rate S/N Ratio: 0 [ if not an image trigger ]
Image S/N Ratio: 7.02
Flight Position: [ source = BAT ]
RA: 271.841486050591 Dec: 27.1718850726204 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 271.917730557926 Dec: 27.2304762962838 [deg; J2000]
{ 18h 07m 40.3s , +27d 13' 49.7" }
+/- 5.16943167272399 [arcmin] (estimated 90% radius based on SNR)
+/- 3.96611586984702 [arcmin] (formal 1-sigma fit error)
SNR: 2.91014334028655
Angular difference between Flight and Ground position is 5.377102 arcmin
Partial Coding Fraction: 0.609375 [ including projection effects ]
Duration
T90: 50.2479999065399 +/- 18.2761922429689
Measured from: 5.10000014305115
to: 55.3480000495911 [s; relative to TRIGTIME]
T50: 34.3319998979568 +/- 22.348628325848
Measured from: 5.68800014257431
to: 40.0200000405312 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 27.3439999818802
to: 28.3439999818802 [s; relative to TRIGTIME]
Total Fluence
Measured from: -2.98400002717972
to: 56.8640000224113 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.293210 0.206395 -0.005850 0.079838
0.059348 0.057079 0.049916 0.047141 [error]
Peak 0.016036 0.023831 0.007100 0.004309
0.007602 0.007411 0.006574 0.006173 [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 1.02e-07 7.99e-08 4.22e-08 3.24e-08 2.39e-07 2.56e-07 erg/cm2
Error 2.99e-08 3.00e-08 3.19e-08 5.12e-08 8.46e-08 1.10e-07 erg/cm2
Peak flux Power-law 2.09e-01 1.41e-01 6.24e-02 3.81e-02 4.32e-01 4.52e-01 ph/cm2/s
Error 1.12e-01 6.26e-02 4.45e-02 5.55e-02 1.86e-01 1.97e-01 ph/cm2/s
Fluence Cutoff-PL 1.03e-07 9.46e-08 9.49e-09 2.66e-11 2.07e-07 2.06e-07 erg/cm2
Error 3.36e-08 4.08e-08 2.53e-08 1.67e-08 6.23e-08 6.23e-08 erg/cm2
Peak flux Cutoff-PL 1.50e-01 2.09e-01 4.85e-02 7.35e-04 4.09e-01 4.08e-01 ph/cm2/s
Error 1.14e-01 8.99e-02 5.00e-02 1.96e-02 1.75e-01 1.75e-01 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 2.921 0.684 - - 3.44e-04 2.76e-04 53.620 57
CPL -0.342 0.000 20.5 0.0 7.28e-02 0.00e+00 50.980 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 2.179 0.792 - - 2.64e-03 2.07e-03 55.390 57
CPL -1.527 1.008 36.9 29.3 4.37e-01 1.96e+01 52.520 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 59.848 -2.984 56.864
T90 50.248 5.100 55.348
T50 34.332 5.688 40.020
Peak 1.000 27.344 28.344
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
271.9177 +27.2305 0.0665 36.3 173.4 1.5169 2.9 TRIG_00420256
------------------------------------------
Foreground time interval of the image:
-2.984 56.864 (delta_t = 59.848 [sec])
Background time interval of the image:
-5.499 -2.984 (delta_t = 2.515 [sec])
Lightcurves
Notes:
- 1) All plots contain as much data as has been downloaded to date.
- 2) Multiple plots of different time binning/intervals are shown to cover all scenarios of short/long GRBs, rate/image triggers, and real/false positives.
- 3) 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.
- 4) 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.
- 5) 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 -2.984 sec. to 56.864 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.92078 ( -0.598545 0.769431 )
Norm@50keV : 3.43720E-04 ( -0.00034372 0.000207829 )
------------------------------------------------------------
# Chi-Squared = 53.62 using 59 PHA bins.
# Reduced chi-squared = 0.9406 for 57 degrees of freedom
# Null hypothesis probability = 6.028055e-01
Photon flux (15-150 keV) in 59.85 sec: 8.92879E-02 ( -0.0243142 0.0244077 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.38597e-07 ( -7.93713e-08 8.97989e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -2.984 sec. to 56.864 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.341675 ( )
Epeak [keV] : 20.5087 ( )
Norm@50keV : 7.27628E-02 ( )
------------------------------------------------------------
# Chi-Squared = 50.98 using 59 PHA bins.
# Reduced chi-squared = 0.9104 for 56 degrees of freedom
# Null hypothesis probability = 6.647898e-01
Photon flux (15-150 keV) in 59.85 sec: 8.75256E-02 ( -0.0231031 0.0232804 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.06727e-07 ( -5.8592e-08 6.59517e-08 ) ergs/cm2
Band function
Time interval is from -2.984 sec. to 56.864 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 0.671861 ( 1.5368 6.02246 )
beta : -8.42723 ( 5.28665 14.6575 )
Epeak [keV] : 21.4970 ( -9.50882 89.8874 )
Norm@50keV : 0.120148 ( -0.12015 140.682 )
------------------------------------------------------------
# Chi-Squared = 50.93 using 59 PHA bins.
# Reduced chi-squared = 0.9259 for 55 degrees of freedom
# Null hypothesis probability = 6.309986e-01
Photon flux (15-150 keV) in 59.85 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] : 5.85164 (-1.34015 1.57409)
R^2/D10^2 : 0.386436 (-0.252739 0.859187)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
# Chi-Squared = 50.88 using 59 PHA bins.
# Reduced chi-squared = 0.8927 for 57 degrees of freedom
# Null hypothesis probability = 7.024899e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.014e-07 5.856e-08
25- 50 9.572e-08 6.087e-08
50-150 7.902e-09 6.898e-09
15-150 2.050e-07 1.232e-07
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 18.5009 (-7.38333 14.1393)
Norm : 1.21358 (-0.581863 1.22708)
------------------------------------------------------------
# Chi-Squared = 51.84 using 59 PHA bins.
# Reduced chi-squared = 0.9094 for 57 degrees of freedom
# Null hypothesis probability = 6.685664e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.051e-07 5.704e-08
25- 50 8.652e-08 5.063e-08
50-150 2.266e-08 1.940e-08
15-150 2.143e-07 1.127e-07
Double BB
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 1.28188E-04 ( )
R1^2/D10^2 : 0.880772 (-0.880772 -0.880772)
kT2 [keV] : 5.85163 (-1.34015 1.57408)
R2^2/D10^2 : 0.386438 (-0.252737 0.859192)
------------------------------------------------------------
# Chi-Squared = 50.96 using 59 PHA bins.
# Chi-Squared = 50.88 using 59 PHA bins.
# Reduced chi-squared = 0.9265 for 55 degrees of freedom
# Reduced chi-squared = 0.9252 for 55 degrees of freedom
# Null hypothesis probability = 6.297155e-01
# Null hypothesis probability = 6.325501e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.028e-07 4.216e-06
25- 50 9.387e-08 1.385e-05
50-150 1.071e-08 7.661e-05
15-150 2.074e-07 1.389e-04
Peak spectrum fit
Power-law model
Time interval is from 27.344 sec. to 28.344 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.17946 ( -0.691419 0.891751 )
Norm@50keV : 2.63990E-03 ( -0.00263836 0.00149476 )
------------------------------------------------------------
# Chi-Squared = 55.39 using 59 PHA bins.
# Reduced chi-squared = 0.9717 for 57 degrees of freedom
# Null hypothesis probability = 5.358250e-01
Photon flux (15-150 keV) in 1 sec: 0.432164 ( -0.186256 0.186259 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.47338e-08 ( -1.19992e-08 1.32779e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 27.344 sec. to 28.344 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.52703 ( 1.58498 3.60183 )
Epeak [keV] : 36.8802 ( -36.8967 21.7199 )
Norm@50keV : 0.437360 ( -0.538475 38.6066 )
------------------------------------------------------------
# Chi-Squared = 52.52 using 59 PHA bins.
# Reduced chi-squared = 0.9379 for 56 degrees of freedom
# Null hypothesis probability = 6.073300e-01
Photon flux (15-150 keV) in 1 sec: 0.408563 ( -0.166821 0.183263 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.14179e-08 ( -8.9826e-09 1.12437e-08 ) ergs/cm2
Band function
Time interval is from 27.344 sec. to 28.344 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 2.06652 ( -4.11061 -2.09287 )
beta : -9.99971 ( 10823.6 10833.6 )
Epeak [keV] : 36.7237 ( -31.3396 21.6632 )
Norm@50keV : 0.933889 ( -0.933891 29.9121 )
------------------------------------------------------------
# Chi-Squared = 52.50 using 59 PHA bins.
# Reduced chi-squared = 0.9546 for 55 degrees of freedom
# Null hypothesis probability = 5.705644e-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] : 9.49004 (-2.94918 4.0527)
R^2/D10^2 : 0.277561 (-0.277561 0.886788)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
# Chi-Squared = 52.49 using 59 PHA bins.
# Reduced chi-squared = 0.9209 for 57 degrees of freedom
# Null hypothesis probability = 6.446857e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 4.990e-09 3.228e-09
25- 50 1.150e-08 7.345e-09
50-150 5.148e-09 4.190e-09
15-150 2.164e-08 1.386e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 44.4057 (-25.6892 120.299)
Norm : 2.74047 (-1.42228 2.85222)
------------------------------------------------------------
# Chi-Squared = 54.04 using 59 PHA bins.
# Reduced chi-squared = 0.9481 for 57 degrees of freedom
# Null hypothesis probability = 5.867219e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 6.500e-09 4.159e-09
25- 50 8.929e-09 6.060e-09
50-150 7.715e-09 6.120e-09
15-150 2.314e-08 1.572e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 0.168724 (-0.168724 -0.168724)
R1^2/D10^2 : 1.26944 (-1.26944 -1.26944)
kT2 [keV] : 9.48973 (-2.94887 4.05301)
R2^2/D10^2 : 0.277595 (-0.212486 0.886643)
------------------------------------------------------------
# Chi-Squared = 52.49 using 59 PHA bins.
# Reduced chi-squared = 0.9544 for 55 degrees of freedom
# Null hypothesis probability = 5.710454e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 0.000e+00 0.000e+00
25- 50 0.000e+00 0.000e+00
50-150 0.000e+00 0.000e+00
15-150 0.000e+00 0.000e+00
Plot creation:
Sat Apr 24 08:16:07 EDT 2010