batgrbproduct analysis for trigger=826428
batgrbproduct Analysis for Trigger=826428
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 15 downlinks after the trigger.
======================================================================
BAT GRB EVENT DATA PROCESSING REPORT
Process Script Ver: batgrbproduct v2.46
Process Start Time (local time): Thu Apr 19 04:03:46 EDT 2018
Host Name: bat1
Current Working Dir: /local/data/bat1/prebascript/trigger826428/GCN5_download_cron
======================================================================
Trigger: 00826428 Segment: 000
BAT Trigger Time: 545726666.816 [s; MET]
Trigger Stop: 545726667.264 [s; MET]
UTC: 2018-04-18T06:44:06.012000 [includes UTCF correction]
Where From?: (*SHORT BURST*) Expanded to TRIGTIME - 64 ms to TRIGTIME + 320 ms
BAT
RA: 170.112382201695 Dec: 24.9562917733818 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 8.81
Image Trigger?: NO
Rate S/N Ratio: 22.8473193175917 [ if not an image trigger ]
Image S/N Ratio: 8.81
Flight Position: [ source = BAT ]
RA: 170.112382201695 Dec: 24.9562917733818 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 170.13164079634 Dec: 24.9246924483515 [deg; J2000]
{ 11h 20m 31.6s , +24d 55' 28.9" }
+/- 1.15595374053186 [arcmin] (estimated 90% radius based on SNR)
+/- 0.402700052988689 [arcmin] (formal 1-sigma fit error)
SNR: 24.7288229277093
Angular difference between Flight and Ground position is 2.166209 arcmin
Partial Coding Fraction: 1 [ including projection effects ]
Duration
T90: 2.28799998760223 +/- 0.825978196121878
Measured from: 0.272000193595886
to: 2.56000018119812 [s; relative to TRIGTIME]
T50: 0.704000115394592 +/- 0.131939416102577
Measured from: 0.464000105857849
to: 1.16800022125244 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 0.228000044822693
to: 1.22800004482269 [s; relative to TRIGTIME]
Total Fluence
Measured from: 0.0959999561309814
to: 3.50400006771088 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.126238 0.211586 0.141833 0.049366
0.010941 0.011941 0.010686 0.008549 [error]
Peak 0.097270 0.154122 0.100524 0.040399
0.006924 0.007975 0.007048 0.005316 [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 4.03e-08 7.70e-08 1.14e-07 3.62e-07 3.22e-07 5.93e-07 erg/cm2
Error 4.54e-09 5.38e-09 1.03e-08 6.93e-08 2.50e-08 7.75e-08 erg/cm2
Peak flux Power-law 9.51e-01 9.98e-01 7.42e-01 8.90e-01 3.03e+00 3.58e+00 ph/cm2/s
Error 1.02e-01 6.53e-02 5.80e-02 1.44e-01 1.87e-01 2.25e-01 ph/cm2/s
Fluence Cutoff-PL 3.82e-08 8.06e-08 1.16e-07 1.95e-07 3.10e-07 4.30e-07 erg/cm2
Error 5.18e-09 6.92e-09 1.10e-08 1.32e-07 2.86e-08 1.50e-07 erg/cm2
Peak flux Cutoff-PL 9.43e-01 1.00e+00 7.45e-01 8.33e-01 3.03e+00 3.52e+00 ph/cm2/s
Error 1.13e-01 7.30e-02 6.22e-02 2.34e-01 1.91e-01 3.26e-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 1.435 0.116 - - 9.83e-03 6.81e-04 58.890 57
CPL 1.050 0.472 118.9 -37.7 1.56e-02 9.62e-03 56.830 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.429 0.107 - - 2.47e-02 1.54e-03 52.620 57
CPL 1.341 0.291 340.6 -54.6 2.74e-02 9.52e-03 52.730 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: 1.024000 sec.
T50 in the 50-300 keV band: 0.512000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 3.408 0.096 3.504
T90 2.288 0.272 2.560
T50 0.704 0.464 1.168
Peak 1.000 0.228 1.228
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
170.1316 +24.9247 0.0077 14.5 167.4 0.5433 24.7 TRIG_00826428
------------------------------------------
Foreground time interval of the image:
0.096 3.504 (delta_t = 3.408 [sec])
Background time interval of the image:
-238.816 -78.436 (delta_t = 160.380 [sec])
-77.816 0.096 (delta_t = 77.912 [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 0.096 sec. to 3.504 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.43521 ( -0.115752 0.116462 )
Norm@50keV : 9.83170E-03 ( -0.000682834 0.000680143 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.89 using 59 PHA bins.
# Reduced chi-squared = 1.033 for 57 degrees of freedom
# Null hypothesis probability = 4.062834e-01
Photon flux (15-150 keV) in 3.408 sec: 1.20724 ( -0.0818739 0.0819135 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.21521e-07 ( -2.49265e-08 2.51298e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.096 sec. to 3.504 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.04980 ( -0.513461 0.430367 )
Epeak [keV] : 118.869 ( -43.5241 -118.876 )
Norm@50keV : 1.56473E-02 ( -0.0061223 0.0131142 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.83 using 59 PHA bins.
# Reduced chi-squared = 1.015 for 56 degrees of freedom
# Null hypothesis probability = 4.439652e-01
Photon flux (15-150 keV) in 3.408 sec: 1.18855 ( -0.08478 0.0848 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.10441e-07 ( -2.87424e-08 2.84963e-08 ) ergs/cm2
Band function
Time interval is from 0.096 sec. to 3.504 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 4.84491 ( -6.73183 -4.84491 )
beta : -1.62992 ( -0.160303 0.150746 )
Epeak [keV] : 29.1433 ( -4.07211 3.25254 )
Norm@50keV : 314.183 ( -20.9104 678.455 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 50.24 using 59 PHA bins.
# Reduced chi-squared = 0.9134 for 55 degrees of freedom
# Null hypothesis probability = 6.568519e-01
Photon flux (15-150 keV) in 3.408 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] : 14.1048 (-1.20507 1.35311)
R^2/D10^2 : 0.171756 (-0.0471216 0.0631749)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 97.90 using 59 PHA bins.
# Reduced chi-squared = 1.718 for 57 degrees of freedom
# Null hypothesis probability = 6.133837e-04
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.458e-08 2.977e-09
25- 50 9.210e-08 8.281e-09
50-150 1.211e-07 1.830e-08
15-150 2.378e-07 2.121e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 200.000 (-34.1523 -200)
Norm : 4.94040 (-0.332371 0.332371)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.15 using 59 PHA bins.
# Reduced chi-squared = 1.038 for 57 degrees of freedom
# Null hypothesis probability = 3.968688e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 4.207e-08 3.374e-09
25- 50 8.093e-08 8.111e-09
50-150 1.775e-07 4.877e-08
15-150 3.005e-07 5.717e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 8.92908 (-1.5047 1.6021)
R1^2/D10^2 : 0.622735 (-0.241838 0.454127)
kT2 [keV] : 38.7092 (-12.0695 42.583)
R2^2/D10^2 : 4.08914E-03 (-0.00344034 0.00560655)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 50.22 using 59 PHA bins.
# Reduced chi-squared = 0.9131 for 55 degrees of freedom
# Null hypothesis probability = 6.573755e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 3.557e-08 6.625e-09
25- 50 8.750e-08 1.736e-08
50-150 1.965e-07 8.807e-08
15-150 3.196e-07 1.010e-07
Peak spectrum fit
Power-law model
Time interval is from 0.228 sec. to 1.228 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.42892 ( -0.107103 0.107811 )
Norm@50keV : 2.47339E-02 ( -0.00154061 0.00153552 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 52.62 using 59 PHA bins.
# Reduced chi-squared = 0.9232 for 57 degrees of freedom
# Null hypothesis probability = 6.399372e-01
Photon flux (15-150 keV) in 1 sec: 3.03251 ( -0.186648 0.186756 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.37627e-07 ( -1.65509e-08 1.66523e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.228 sec. to 1.228 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.34084 ( -0.438539 0.143293 )
Epeak [keV] : 340.573 ( -656.074 -765.359 )
Norm@50keV : 2.74254E-02 ( -0.00258473 0.0164601 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 52.73 using 59 PHA bins.
# Reduced chi-squared = 0.9416 for 56 degrees of freedom
# Null hypothesis probability = 5.993625e-01
Photon flux (15-150 keV) in 1 sec: 3.02610 ( -0.19153 0.19114 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.36825e-07 ( -1.811e-08 1.7399e-08 ) ergs/cm2
Band function
Time interval is from 0.228 sec. to 1.228 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.736877 ( 0.725515 0.725515 )
beta : -1.54636 ( -0.261751 0.189894 )
Epeak [keV] : 68.3619 ( -67.2508 193.151 )
Norm@50keV : 6.40331E-02 ( -0.0665707 2.33945e+06 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 51.13 using 59 PHA bins.
# Reduced chi-squared = 0.9297 for 55 degrees of freedom
# Null hypothesis probability = 6.230814e-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] : 14.5918 ( )
R^2/D10^2 : 0.380521 ( )
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 118.59 using 59 PHA bins.
# Reduced chi-squared = 2.0806 for 57 degrees of freedom
# Null hypothesis probability = 3.218240e-06
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.703e-08 1.955e-09
25- 50 6.595e-08 5.130e-09
50-150 9.437e-08 1.202e-08
15-150 1.774e-07 1.395e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 200.000 (-25.5752 -200)
Norm : 12.4475 (-0.755394 0.755394)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.91 using 59 PHA bins.
# Reduced chi-squared = 0.9985 for 57 degrees of freedom
# Null hypothesis probability = 4.783454e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 3.099e-08 2.165e-09
25- 50 5.962e-08 5.255e-09
50-150 1.308e-07 2.555e-08
15-150 2.214e-07 3.850e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 9.24226 (-1.4461 1.47138)
R1^2/D10^2 : 1.40672 (-0.506065 0.943759)
kT2 [keV] : 47.2937 (-15.6666 64.2491)
R2^2/D10^2 : 6.15954E-03 (-0.00531797 0.0143138)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 49.90 using 59 PHA bins.
# Reduced chi-squared = 0.9073 for 55 degrees of freedom
# Null hypothesis probability = 6.692442e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.527e-08 4.155e-09
25- 50 6.369e-08 1.059e-08
50-150 1.511e-07 6.495e-08
15-150 2.401e-07 7.105e-08
Plot creation:
Thu Apr 19 05:30:09 EDT 2018