batgrbproduct Analysis for Trigger=638589
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 Apr 21 18:36:49 EDT 2015
Host Name: bat1
Current Working Dir: /local/data/bat1/prebascript/trigger638589/GCN5_download_cron
======================================================================
Trigger: 00638589 Segment: 000
BAT Trigger Time: 451242024 [s; MET]
Trigger Stop: 451242368 [s; MET]
UTC: 2015-04-20T17:00:10.527480 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 87.8153793256478 Dec: -10.4224915475194 [deg; J2000]
Catalogged Source?: YES
Point Source?: YES
GRB Indicated?: NO [ by BAT flight software ]
Image S/N Ratio: 5.81
Image Trigger?: YES
Rate S/N Ratio: 0 [ if not an image trigger ]
Image S/N Ratio: 5.81
Flight Position: [ source = BAT ]
RA: 87.8153793256478 Dec: -10.4224915475194 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 87.8726987649503 Dec: -10.5260531547643 [deg; J2000]
{ 05h 51m 29.4s , -10d 31' 33.8" }
+/- 4.95764855849086 [arcmin] (estimated 90% radius based on SNR)
+/- 2.67149484005019 [arcmin] (formal 1-sigma fit error)
SNR: 3.08935152128523
Angular difference between Flight and Ground position is 7.074389 arcmin
Partial Coding Fraction: 0.796875 [ including projection effects ]
Duration
T90: 416.799999952316 +/- 48.3379910583562
Measured from: 25.3720000982285
to: 442.172000050545 [s; relative to TRIGTIME]
T50: 187.083999931812 +/- 22.8604140470588
Measured from: 116.704000115395
to: 303.788000047207 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 178.796000003815
to: 179.796000003815 [s; relative to TRIGTIME]
Total Fluence
Measured from: -13.8640000224113
to: 499.959999978542 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 2.301468 4.407008 1.351704 1.787411
0.164420 0.185683 0.163947 0.178283 [error]
Peak 0.020381 0.016151 0.021352 0.019648
0.007861 0.009141 0.008071 0.009480 [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 8.12e-07 1.33e-06 1.64e-06 4.01e-06 4.91e-06 7.79e-06 erg/cm2
Error -------- -------- -------- -------- -------- -------- erg/cm2
Peak flux Power-law 1.65e-01 1.70e-01 1.23e-01 1.43e-01 5.13e-01 6.00e-01 ph/cm2/s
Error 9.92e-02 6.74e-02 6.72e-02 1.82e-01 1.99e-01 2.56e-01 ph/cm2/s
Fluence Cutoff-PL 6.62e-07 1.86e-06 7.48e-07 1.47e-08 3.29e-06 3.29e-06 erg/cm2
Error -------- -------- -------- -------- -------- -------- erg/cm2
Peak flux Cutoff-PL 1.38e-01 1.90e-01 1.31e-01 4.54e-02 4.92e-01 5.05e-01 ph/cm2/s
Error 1.32e-01 9.14e-02 7.77e-02 9.17e-02 2.18e-01 2.27e-01 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 1.694 0.000 - - 1.04e-03 0.00e+00 156.590 57
CPL -2.246 0.000 38.4 0.0 2.96e-01 0.00e+00 125.580 56
The chi2 of BB fit is 127.88 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 1.464 0.737 - - 4.15e-03 1.79e-03 42.870 57
CPL 0.324 1.051 70.1 0.0 1.64e-02 3.47e+02 42.580 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: 345.280000 sec.
T50 in the 50-300 keV band: 159.168000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 513.824 -13.864 499.960
T90 416.800 25.372 442.172
T50 187.084 116.704 303.788
Peak 1.000 178.796 179.796
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
87.8727 -10.5261 0.0621 16.5 69.4 14.2318 3.1 TRIG_00638589
------------------------------------------
Foreground time interval of the image:
-13.864 154.480 (delta_t = 168.344 [sec])
156.000 419.040 (delta_t = 263.040 [sec])
420.000 495.301 (delta_t = 75.301 [sec])
Background time interval of the image:
-16.499 -13.864 (delta_t = 2.635 [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
Multiple GTIs in the spectrum
tstart tstop
-13.864000 154.480000
156.000000 419.040000
420.000000 499.960000
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.69358 ( )
Norm@50keV : 1.03676E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 156.59 using 59 PHA bins.
# Reduced chi-squared = 2.7473 for 57 degrees of freedom
# Null hypothesis probability = 3.154577e-11
Photon flux (15-150 keV) in 511.3 sec: 0.137386 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 4.91059e-06 ( 0 0 ) ergs/cm2
Cutoff power-law model
Multiple GTIs in the spectrum
tstart tstop
-13.864000 154.480000
156.000000 419.040000
420.000000 499.960000
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.24575 ( )
Epeak [keV] : 38.4466 ( )
Norm@50keV : 0.296500 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 125.58 using 59 PHA bins.
# Reduced chi-squared = 2.2425 for 56 degrees of freedom
# Null hypothesis probability = 2.968989e-07
Photon flux (15-150 keV) in 511.3 sec: 0.120105 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 3.28802e-06 ( 0 0 ) ergs/cm2
Band function
Multiple GTIs in the spectrum
tstart tstop
-13.864000 154.480000
156.000000 419.040000
420.000000 499.960000
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 4.16521 ( -1.60349 -4.07021 )
beta : -2.80774 ( -0.492802 0.373988 )
Epeak [keV] : 34.8712 ( -2.12474 1.93128 )
Norm@50keV : 6.18980 ( -6.18996 13.2445 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 98.54 using 59 PHA bins.
# Reduced chi-squared = 1.792 for 55 degrees of freedom
# Null hypothesis probability = 2.840804e-04
Photon flux (15-150 keV) in 511.3 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] : 10.0460 ( )
R^2/D10^2 : 6.75239E-02 ( )
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 127.88 using 59 PHA bins.
# Reduced chi-squared = 2.2436 for 57 degrees of freedom
# Null hypothesis probability = 2.327183e-07
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 7.107e-07 7.030e-08
25- 50 1.779e-06 1.232e-07
50-150 9.406e-07 1.664e-07
15-150 3.430e-06 2.531e-07
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 105.109 ( )
Norm : 0.602481 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 148.69 using 59 PHA bins.
# Reduced chi-squared = 2.6086 for 57 degrees of freedom
# Null hypothesis probability = 4.064731e-10
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 8.050e-07 8.155e-08
25- 50 1.406e-06 1.117e-07
50-150 2.342e-06 7.422e-07
15-150 4.553e-06 8.508e-07
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 4.03925E-02 ( )
R1^2/D10^2 : 3.53524E+17 ( )
kT2 [keV] : 10.0459 ( )
R2^2/D10^2 : 6.75243E-02 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 127.88 using 59 PHA bins.
# Reduced chi-squared = 2.3252 for 55 degrees of freedom
# Null hypothesis probability = 9.756558e-08
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 178.796 sec. to 179.796 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.46350 ( -0.695853 0.778114 )
Norm@50keV : 4.14857E-03 ( -0.00185269 0.0017305 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 42.87 using 59 PHA bins.
# Reduced chi-squared = 0.7520 for 57 degrees of freedom
# Null hypothesis probability = 9.175008e-01
Photon flux (15-150 keV) in 1 sec: 0.512989 ( -0.19915 0.19915 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.96018e-08 ( -1.84058e-08 1.97105e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 178.796 sec. to 179.796 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.323642 ( -0.321702 1.78073 )
Epeak [keV] : 70.1391 ( -70.0963 -70.0963 )
Norm@50keV : 1.63877E-02 ( -0.0164474 693.666 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 42.58 using 59 PHA bins.
# Reduced chi-squared = 0.7604 for 56 degrees of freedom
# Null hypothesis probability = 9.069206e-01
Photon flux (15-150 keV) in 1 sec: 0.491741 ( -0.227639 0.207528 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.61081e-08 ( -1.70072e-08 2.21775e-08 ) ergs/cm2
Band function
Time interval is from 178.796 sec. to 179.796 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.791390 ( 0.886921 5.73655 )
beta : -9.45687 ( 9.99329 19.9933 )
Epeak [keV] : 86.0793 ( -52.6479 -86.0793 )
Norm@50keV : 9.33164E-03 ( -0.00362076 0.00362076 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 42.62 using 59 PHA bins.
# Reduced chi-squared = 0.7749 for 55 degrees of freedom
# Null hypothesis probability = 8.883274e-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] : 14.7617 (-4.86813 8.36376)
R^2/D10^2 : 6.57137E-02 (-0.0657137 0.190181)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 42.84 using 59 PHA bins.
# Reduced chi-squared = 0.7516 for 57 degrees of freedom
# Null hypothesis probability = 9.178902e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 3.006e-09 1.930e-09
25- 50 1.176e-08 7.725e-09
50-150 1.732e-08 1.270e-08
15-150 3.209e-08 1.993e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 199.363 (-199.363 -199.363)
Norm : 2.09740 (-0.812207 0.812424)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 42.78 using 59 PHA bins.
# Reduced chi-squared = 0.7505 for 57 degrees of freedom
# Null hypothesis probability = 9.190058e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 5.223e-09 3.428e-09
25- 50 1.005e-08 6.480e-09
50-150 2.203e-08 1.443e-08
15-150 3.730e-08 2.400e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 2.39292 (-2.3737 17.4735)
R1^2/D10^2 : 61.1433 (-87.2676 639.348)
kT2 [keV] : 16.5233 (-5.74997 11.3484)
R2^2/D10^2 : 4.12372E-02 (-0.0421536 0.14226)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 41.31 using 59 PHA bins.
# Reduced chi-squared = 0.7511 for 55 degrees of freedom
# Null hypothesis probability = 9.142431e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 4.736e-09 2.087e-09
25- 50 1.014e-08 6.110e-09
50-150 1.929e-08 1.196e-08
15-150 3.416e-08 2.052e-08
Plot creation:
Tue Apr 21 18:41:40 EDT 2015