batgrbproduct Analysis for Trigger=501752
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): Tue Aug 30 21:04:15 EDT 2011
Host Name: gcn5
Current Working Dir: /local/data/raid16/prebascript_archive/trigger501752/GCN5_download_cron
======================================================================
Trigger: 00501752 Segment: 000
BAT Trigger Time: 336354079.568 [s; MET]
Trigger Stop: 336354079.584 [s; MET]
UTC: 2011-08-29T23:41:12.256360 [includes UTCF correction]
Where From?: (*SHORT BURST*) TDRSS scaled map message
BAT
RA: 278.720563404872 Dec: -8.75131143344119 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 7.27
Image Trigger?: NO
Rate S/N Ratio: 19.5703857907809 [ if not an image trigger ]
Image S/N Ratio: 7.27
Flight Position: [ source = BAT ]
RA: 278.720563404872 Dec: -8.75131143344119 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 278.7095326891 Dec: -8.76989483705778 [deg; J2000]
{ 18h 34m 50.3s , -08d 46' 11.6" }
+/- 3.05558123513027 [arcmin] (estimated 90% radius based on SNR)
+/- 1.82301712675347 [arcmin] (formal 1-sigma fit error)
SNR: 6.16775605270338
Angular difference between Flight and Ground position is 1.292714 arcmin
Partial Coding Fraction: 0.5703125 [ including projection effects ]
Duration
T90: 0.0119999051094055 +/- 0.00565686571343518
Measured from: 1.19209289550781e-07
to: 0.0120000243186951 [s; relative to TRIGTIME]
T50: 0.0079999566078186 +/- 0.004
Measured from: 1.19209289550781e-07
to: 0.00800007581710815 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: -0.492000043392181
to: 0.507999956607819 [s; relative to TRIGTIME]
Total Fluence
Measured from: 0
to: 0.0119999647140503 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.006944 0.006675 0.003828 -0.000279
0.001492 0.001598 0.001312 0.000610 [error]
Peak 0.007227 0.023703 0.004510 -0.006152
0.006973 0.007334 0.006067 0.006015 [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 1.35e-09 9.20e-10 4.16e-10 2.67e-10 2.82e-09 2.90e-09 erg/cm2
Error 5.86e-10 4.52e-10 3.07e-10 3.36e-10 1.26e-09 1.42e-09 erg/cm2
Peak flux Power-law 1.44e-01 1.16e-01 6.34e-02 5.07e-02 3.46e-01 3.74e-01 ph/cm2/s
Error 1.04e-01 8.84e-02 4.81e-02 8.23e-02 1.81e-01 1.97e-01 ph/cm2/s
Fluence Cutoff-PL 8.27e-10 3.56e-09 1.44e-09 1.32e-11 5.84e-09 5.83e-09 erg/cm2
Error 8.50e-10 1.16e-09 9.68e-10 3.73e-11 1.76e-09 1.76e-09 erg/cm2
Peak flux Cutoff-PL 1.05e-01 1.46e-01 6.67e-02 6.97e-03 3.24e-01 3.25e-01 ph/cm2/s
Error 1.20e-01 9.33e-02 5.75e-02 7.11e-02 2.56e-01 2.71e-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 1.02e-01 3.10e-01 3.16e-01 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 3.140 0.623 - - 1.83e-02 1.12e-02 58.800 57
CPL -3.968 -0.469 39.7 7.8 1.85e+02 2.10e+05 41.670 56
The chi2 of BB fit is 42.92 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 1.873 1.013 - - 2.44e-03 1.95e-03 67.750 57
CPL -10.000 0.000 46.1 9.9 2.33e+03 1.21e+04 66.910 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 0.012 0.000 0.012
T90 0.012 0.000 0.012
T50 0.008 0.000 0.008
Peak 1.000 -0.492 0.508
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
278.7095 -8.7699 0.0313 36.1 -32.2 0.0157 6.2 TRIG_00501752
------------------------------------------
Foreground time interval of the image:
0.000 0.012 (delta_t = 0.012 [sec])
Background time interval of the image:
-239.568 0.000 (delta_t = 239.568 [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 0.012 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 3.13963 ( -0.481445 0.764114 )
Norm@50keV : 1.82565E-02 ( -0.0110047 0.0113523 )
------------------------------------------------------------
# Chi-Squared = 58.80 using 59 PHA bins.
# Reduced chi-squared = 1.032 for 57 degrees of freedom
# Null hypothesis probability = 4.094682e-01
Photon flux (15-150 keV) in 0.012 sec: 5.56938 ( -2.39125 2.3872 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.82134e-09 ( -1.21277e-09 1.3014e-09 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.000 sec. to 0.012 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -3.96794 ( 4.02666 3.08821 )
Epeak [keV] : 39.7283 ( -7.65284 7.97886 )
Norm@50keV : 184.574 ( -219.921 419895 )
------------------------------------------------------------
# Chi-Squared = 41.67 using 59 PHA bins.
# Reduced chi-squared = 0.7441 for 56 degrees of freedom
# Null hypothesis probability = 9.230640e-01
Photon flux (15-150 keV) in 0.012 sec: 8.53828 ( -2.91363 2.84762 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.84126e-09 ( -1.74704e-09 1.77526e-09 ) ergs/cm2
Band function
Time interval is from 0.000 sec. to 0.012 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 4.21457 ( -2.44166 -3.80718 )
beta : -10.00000 ( 2.15748e+06 2.15749e+06 )
Epeak [keV] : 40.1044 ( -8.60439 5.64732 )
Norm@50keV : 240.579 ( -240.656 147.13 )
------------------------------------------------------------
# Chi-Squared = 41.73 using 59 PHA bins.
# Reduced chi-squared = 0.7587 for 55 degrees of freedom
# Null hypothesis probability = 9.065041e-01
Photon flux (15-150 keV) in 0.012 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] : 9.18729 (-1.68479 1.39554)
R^2/D10^2 : 6.86768 (-3.41282 7.48985)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
# Chi-Squared = 42.92 using 59 PHA bins.
# Reduced chi-squared = 0.7531 for 57 degrees of freedom
# Null hypothesis probability = 9.164854e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.368e-09 6.114e-10
25- 50 3.003e-09 1.337e-09
50-150 1.220e-09 8.386e-10
15-150 5.590e-09 2.560e-09
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 25.0600 (-8.43643 9.57321)
Norm : 74.3275 (-31.0284 44.0671)
------------------------------------------------------------
# Chi-Squared = 51.25 using 59 PHA bins.
# Reduced chi-squared = 0.8990 for 57 degrees of freedom
# Null hypothesis probability = 6.897806e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.636e-09 6.793e-10
25- 50 1.680e-09 8.516e-10
50-150 7.167e-10 6.288e-10
15-150 4.032e-09 2.097e-09
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 0.226118 (-0.226118 -0.226118)
R1^2/D10^2 : 0.792745 (-0.792745 -0.792745)
kT2 [keV] : 9.22348 (-1.65886 1.42052)
R2^2/D10^2 : 6.77235 (-3.35953 7.54109)
------------------------------------------------------------
# Chi-Squared = 42.92 using 59 PHA bins.
# Reduced chi-squared = 0.7804 for 55 degrees of freedom
# Null hypothesis probability = 8.817246e-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
Peak spectrum fit
Power-law model
Time interval is from -0.492 sec. to 0.508 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.87291 ( -0.890065 1.1367 )
Norm@50keV : 2.43842E-03 ( -0.0024387 0.00145235 )
------------------------------------------------------------
# Chi-Squared = 67.75 using 59 PHA bins.
# Reduced chi-squared = 1.189 for 57 degrees of freedom
# Null hypothesis probability = 1.560248e-01
Photon flux (15-150 keV) in 1 sec: 0.345979 ( -0.180872 0.181396 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.24189e-08 ( -1.29952e-08 1.41038e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.492 sec. to 0.508 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -10.0000 ( )
Epeak [keV] : 46.0588 ( -8.7624 10.9695 )
Norm@50keV : 2327.16 ( -2327.17 21956.4 )
------------------------------------------------------------
# Chi-Squared = 66.91 using 59 PHA bins.
# Reduced chi-squared = 1.195 for 56 degrees of freedom
# Null hypothesis probability = 1.509094e-01
Photon flux (15-150 keV) in 1 sec: 0.324071 ( -0.324071 0.188365 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.98789e-08 ( -1.22924e-08 1.47437e-08 ) ergs/cm2
Band function
Time interval is from -0.492 sec. to 0.508 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 0.318670 ( 0.0750399 0.0750399 )
beta : -10.00000 ( 1.40644e+07 1.40644e+07 )
Epeak [keV] : 46.9602 ( -38.9697 -47.0206 )
Norm@50keV : 3.81777E-02 ( -0.045476 10.4833 )
------------------------------------------------------------
# Chi-Squared = 67.07 using 59 PHA bins.
# Reduced chi-squared = 1.219 for 55 degrees of freedom
# Null hypothesis probability = 1.274481e-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] : 11.8855 (-4.71125 8.14308)
R^2/D10^2 : 9.37807E-02 (-0.0937807 0.487794)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
# Chi-Squared = 67.07 using 59 PHA bins.
# Reduced chi-squared = 1.177 for 57 degrees of freedom
# Null hypothesis probability = 1.699788e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.800e-09 1.992e-09
25- 50 8.712e-09 5.830e-09
50-150 7.352e-09 5.690e-09
15-150 1.886e-08 1.269e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 79.5873 (-79.5791 -79.5791)
Norm : 1.66543 (-0.94986 2.12536)
------------------------------------------------------------
# Chi-Squared = 67.38 using 59 PHA bins.
# Reduced chi-squared = 1.182 for 57 degrees of freedom
# Null hypothesis probability = 1.634029e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 4.320e-09 2.862e-09
25- 50 7.103e-09 4.626e-09
50-150 9.991e-09 8.605e-09
15-150 2.141e-08 1.524e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 3.04920 (-3.08586 16.6054)
R1^2/D10^2 : 8.93609 (-8.43959 -8.43959)
kT2 [keV] : 13.1705 (-13.1466 -13.1466)
R2^2/D10^2 : 5.82379E-02 (-0.0586789 0.419403)
------------------------------------------------------------
# Chi-Squared = 66.62 using 59 PHA bins.
# Reduced chi-squared = 1.211 for 55 degrees of freedom
# Null hypothesis probability = 1.353924e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 3.989e-09 1.962e-09
25- 50 7.766e-09 5.100e-09
50-150 8.267e-09 5.725e-09
15-150 2.002e-08 1.190e-08
Plot creation:
Tue Aug 30 21:44:49 EDT 2011