batgrbproduct Analysis for Trigger=638946
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 Apr 25 11:16:43 EDT 2015
Host Name: bat1
Current Working Dir: /local/data/bat1/prebascript/trigger638946/GCN5_download_cron
======================================================================
Trigger: 00638946 Segment: 000
BAT Trigger Time: 451554190.564 [s; MET]
Trigger Stop: 451554190.628 [s; MET]
UTC: 2015-04-24T07:42:57.075440 [includes UTCF correction]
Where From?: (*SHORT BURST*) TDRSS scaled map message
BAT
RA: 152.312128050396 Dec: -26.6466164433475 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 15.22
Image Trigger?: NO
Rate S/N Ratio: 250.966133173383 [ if not an image trigger ]
Image S/N Ratio: 15.22
Flight Position: [ source = BAT ]
RA: 152.312128050396 Dec: -26.6466164433475 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 152.304836738167 Dec: -26.6461138519022 [deg; J2000]
{ 10h 09m 13.2s , -26d 38' 46.0" }
+/- 0.875250267847695 [arcmin] (estimated 90% radius based on SNR)
+/- 0.218886270488057 [arcmin] (formal 1-sigma fit error)
SNR: 36.7948122245624
Angular difference between Flight and Ground position is 0.392176 arcmin
Partial Coding Fraction: 0.6953125 [ including projection effects ]
Duration
T90: 90.9719999432564 +/- 22.1240361727103
Measured from: -0.0199998617172241
to: 90.9520000815392 [s; relative to TRIGTIME]
T50: 4.3199999332428 +/- 25.7340199230362
Measured from: 0.0920001268386841
to: 4.41200006008148 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: -0.0559999942779541
to: 0.944000005722046 [s; relative to TRIGTIME]
Total Fluence
Measured from: -0.0559999942779541
to: 106.324000000954 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.461293 0.699681 0.768858 0.315845
0.062039 0.064458 0.056852 0.048643 [error]
Peak 0.245711 0.450130 0.618419 0.279441
0.011849 0.015352 0.017901 0.015679 [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 1.50e-07 3.26e-07 5.57e-07 2.19e-06 1.53e-06 3.23e-06 erg/cm2
Error 2.58e-08 3.28e-08 5.41e-08 4.98e-07 1.37e-07 5.24e-07 erg/cm2
Peak flux Power-law 2.22e+00 3.39e+00 3.89e+00 8.51e+00 1.20e+01 1.80e+01 ph/cm2/s
Error 1.70e-01 1.55e-01 1.39e-01 6.90e-01 4.15e-01 7.36e-01 ph/cm2/s
Fluence Cutoff-PL 1.52e-07 3.28e-07 5.55e-07 2.14e-06 1.52e-06 3.17e-06 erg/cm2
Error 2.61e-08 3.26e-08 5.44e-08 7.29e-07 1.35e-07 5.37e-07 erg/cm2
Peak flux Cutoff-PL 2.22e+00 3.39e+00 3.89e+00 8.45e+00 1.20e+01 1.80e+01 ph/cm2/s
Error 1.99e-01 9.64e-02 1.62e-01 1.13e+00 4.13e-01 1.31e+00 ph/cm2/s
Fluence Band -------- -------- -------- -------- -------- -------- erg/cm2
Error -------- -------- -------- -------- -------- -------- erg/cm2
Peak flux Band -------- -------- -------- -------- -------- -------- ph/cm2/s
Error -------- -------- -------- -------- -------- -------- ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.226 0.154 - - 1.42e-03 1.19e-04 54.410 57
CPL 1.228 0.155 9999.4 0.0 1.43e-03 3.61e-04 54.440 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 0.805 0.062 - - 1.05e-01 3.67e-03 48.800 57
CPL 0.797 0.063 9998.7 0.0 1.05e-01 1.58e-02 48.800 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: 0.320000 sec.
T50 in the 50-300 keV band: 0.192000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 106.380 -0.056 106.324
T90 90.972 -0.020 90.952
T50 4.320 0.092 4.412
Peak 1.000 -0.056 0.944
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
152.3048 -26.6461 0.0052 34.1 -175.2 1.6865 36.8 TRIG_00638946
------------------------------------------
Foreground time interval of the image:
-0.056 6.737 (delta_t = 6.793 [sec])
Background time interval of the image:
-239.564 -0.056 (delta_t = 239.508 [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 -0.056 sec. to 106.324 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.22630 ( -0.155636 0.152644 )
Norm@50keV : 1.42472E-03 ( -0.000119352 0.000119133 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.41 using 59 PHA bins.
# Reduced chi-squared = 0.9546 for 57 degrees of freedom
# Null hypothesis probability = 5.727680e-01
Photon flux (15-150 keV) in 106.4 sec: 0.167878 ( -0.0149111 0.0149561 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.52679e-06 ( -1.37006e-07 1.37489e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.056 sec. to 106.324 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.22765 ( -0.162026 0.148338 )
Epeak [keV] : 9999.36 ( -9999.36 -9999.36 )
Norm@50keV : 1.43163E-03 ( -0.00011922 0.000603658 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.44 using 59 PHA bins.
# Reduced chi-squared = 0.9721 for 56 degrees of freedom
# Null hypothesis probability = 5.341338e-01
Photon flux (15-150 keV) in 106.4 sec: 0.168219 ( -0.014916 0.014586 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.52257e-06 ( -1.32872e-07 1.37511e-07 ) ergs/cm2
Band function
Time interval is from -0.056 sec. to 106.324 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.926607 ( 0.92617 0.92617 )
beta : -1.22671 ( 1.22665 0.156094 )
Epeak [keV] : 63.3020 ( -63.1219 -63.1219 )
Norm@50keV : 2.62707E-03 ( -0.00116958 80453 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.41 using 59 PHA bins.
# Reduced chi-squared = 0.9893 for 55 degrees of freedom
# Null hypothesis probability = 4.971635e-01
Photon flux (15-150 keV) in 106.4 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] : 20.2716 (-2.39052 2.85138)
R^2/D10^2 : 7.12499E-03 (-0.00250037 0.00370322)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 96.12 using 59 PHA bins.
# Reduced chi-squared = 1.686 for 57 degrees of freedom
# Null hypothesis probability = 9.203215e-04
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 5.973e-08 1.135e-08
25- 50 3.002e-07 4.075e-08
50-150 9.161e-07 1.266e-07
15-150 1.276e-06 1.330e-07
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 200.000 ( )
Norm : 0.706679 (-0.0600836 0.060073)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 69.97 using 59 PHA bins.
# Reduced chi-squared = 1.228 for 57 degrees of freedom
# Null hypothesis probability = 1.160858e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.872e-07 2.123e-08
25- 50 3.601e-07 1.287e-07
50-150 7.898e-07 2.995e-07
15-150 1.337e-06 3.587e-07
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 7.03535 (-1.78613 2.60946)
R1^2/D10^2 : 0.159656 (-0.102461 0.309775)
kT2 [keV] : 34.6460 (-8.00464 21.1895)
R2^2/D10^2 : 1.12083E-03 (-0.000820822 0.00146496)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 55.22 using 59 PHA bins.
# Reduced chi-squared = 1.004 for 55 degrees of freedom
# Null hypothesis probability = 4.663050e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.562e-07 6.817e-08
25- 50 3.207e-07 1.111e-07
50-150 1.083e-06 4.140e-07
15-150 1.560e-06 4.924e-07
Peak spectrum fit
Power-law model
Time interval is from -0.056 sec. to 0.944 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.804541 ( -0.0625151 0.061967 )
Norm@50keV : 0.104697 ( -0.00367498 0.00365774 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 48.80 using 59 PHA bins.
# Reduced chi-squared = 0.8562 for 57 degrees of freedom
# Null hypothesis probability = 7.717524e-01
Photon flux (15-150 keV) in 1 sec: 12.0312 ( -0.414485 0.414806 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.22115e-06 ( -4.5522e-08 4.5627e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.056 sec. to 0.944 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.797205 ( -0.063032 0.0624292 )
Epeak [keV] : 9998.66 ( -9998.67 -9998.67 )
Norm@50keV : 0.105444 ( -0.00363749 0.0279024 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 48.80 using 59 PHA bins.
# Reduced chi-squared = 0.8714 for 56 degrees of freedom
# Null hypothesis probability = 7.415170e-01
Photon flux (15-150 keV) in 1 sec: 12.0280 ( -0.4138 0.4127 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.22161e-06 ( 0 0 ) ergs/cm2
Band function
Time interval is from -0.056 sec. to 0.944 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.910655 ( 0.910655 0.910655 )
beta : -0.804540 ( -0.0619608 0.0625258 )
Epeak [keV] : 13.9206 ( -13.9206 -13.9206 )
Norm@50keV : 0.153770 ( -0.0527962 2.4805e+06 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 48.80 using 59 PHA bins.
# Reduced chi-squared = 0.8873 for 55 degrees of freedom
# Null hypothesis probability = 7.089598e-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] : 25.7534 ( )
R^2/D10^2 : 0.280210 ( )
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 175.12 using 59 PHA bins.
# Reduced chi-squared = 3.0723 for 57 degrees of freedom
# Null hypothesis probability = 6.147126e-14
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 3.177e-08 2.065e-09
25- 50 1.830e-07 9.500e-09
50-150 8.955e-07 4.585e-08
15-150 1.110e-06 4.750e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 199.363 ( )
Norm : 46.5892 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 425.23 using 59 PHA bins.
# Reduced chi-squared = 7.4602 for 57 degrees of freedom
# Null hypothesis probability = 9.392020e-58
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.160e-07 4.250e-09
25- 50 2.232e-07 7.900e-09
50-150 4.894e-07 1.945e-08
15-150 8.286e-07 3.285e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 9.30137 (-2.11712 2.7281)
R1^2/D10^2 : 2.93777 (-1.39259 3.4078)
kT2 [keV] : 42.2678 (-7.17829 16.8028)
R2^2/D10^2 : 5.86110E-02 (-0.0345002 0.0431298)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.25 using 59 PHA bins.
# Reduced chi-squared = 1.059 for 55 degrees of freedom
# Null hypothesis probability = 3.567347e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 6.327e-08 1.057e-08
25- 50 2.024e-07 2.845e-08
50-150 9.659e-07 1.268e-07
15-150 1.231e-06 1.471e-07
Plot creation:
Sat Apr 25 11:20:34 EDT 2015