batgrbproduct Analysis for Trigger=922808
Analysis Summary
Notes:
- 1) No attempt has been made to eliminate the non-significant decimal places.
- 2) This batgrbproduct analysis is done using the HEASARC data.
- 3) This batgrbproduct analysis is using the flight position for the mask-weighting calculation.
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BAT GRB EVENT DATA PROCESSING REPORT
Process Script Ver: batgrbproduct v2.46
Process Start Time (local time): Wed Aug 28 17:44:04 EDT 2019
Host Name: bat1
Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger922808
======================================================================
Trigger: 00922808 Segment: 000
BAT Trigger Time: 588690022.912 [s; MET]
Trigger Stop: 588690023.936 [s; MET]
UTC: 2019-08-28T12:59:59.424820 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 251.818484637617 Dec: 27.2367605883349 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 10.03
Image Trigger?: NO
Rate S/N Ratio: 23.8537208837531 [ if not an image trigger ]
Image S/N Ratio: 10.03
Flight Position: [ source = BAT ]
RA: 251.818484637617 Dec: 27.2367605883349 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 251.838387884022 Dec: 27.2869246830542 [deg; J2000]
{ 16h 47m 21.2s , +27d 17' 12.9" }
+/- 0.975221194161496 [arcmin] (estimated 90% radius based on SNR)
+/- 0.282165456439403 [arcmin] (formal 1-sigma fit error)
SNR: 31.5271951911798
Angular difference between Flight and Ground position is 3.191560 arcmin
Partial Coding Fraction: 1.015625 [ including projection effects ]
Duration
T90: 66.5799999237061 +/- 6.24039258261463
Measured from: -28.7999999523163
to: 37.7799999713898 [s; relative to TRIGTIME]
T50: 24.6039998531342 +/- 2.6524652771161
Measured from: 0.676000118255615
to: 25.2799999713898 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 10.7440000772476
to: 11.7440000772476 [s; relative to TRIGTIME]
Total Fluence
Measured from: -42.3639999628067
to: 53.3400000333786 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 1.596961 2.312677 1.994119 0.543440
0.072643 0.074906 0.067101 0.057449 [error]
Peak 0.074160 0.104776 0.106709 0.036038
0.008476 0.009478 0.009395 0.007267 [error]
[ fluence units of on-axis counts / fully illuminated detector ]
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=== 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 4.42e-07 9.24e-07 1.51e-06 5.55e-06 4.16e-06 8.42e-06 erg/cm2
Error 3.22e-08 3.86e-08 6.57e-08 5.64e-07 1.64e-07 5.99e-07 erg/cm2
Peak flux Power-law 5.98e-01 7.35e-01 6.56e-01 1.01e+00 2.34e+00 3.00e+00 ph/cm2/s
Error 1.01e-01 7.58e-02 7.22e-02 2.36e-01 2.15e-01 3.05e-01 ph/cm2/s
Fluence Cutoff-PL 4.45e-07 9.23e-07 1.50e-06 5.74e-06 4.17e-06 8.51e-06 erg/cm2
Error -------- 4.00e-08 5.85e-08 9.02e-07 1.90e-07 1.34e-06 erg/cm2
Peak flux Cutoff-PL 5.81e-01 7.45e-01 6.67e-01 8.49e-01 2.33e+00 2.84e+00 ph/cm2/s
Error 1.14e-01 8.46e-02 8.18e-02 3.17e-01 2.20e-01 4.58e-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 1.292 0.068 - - 4.40e-03 1.57e-04 48.430 57
CPL 1.278 0.149 9966.7 0.0 4.46e-03 3.63e-04 48.720 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.164 0.160 - - 2.00e-02 1.83e-03 61.180 57
CPL 1.018 0.460 356.9 0.0 2.36e-02 1.41e-02 60.990 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: 68.224000 sec.
T50 in the 50-300 keV band: 19.712000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 95.704 -42.364 53.340
T90 66.580 -28.800 37.780
T50 24.604 0.676 25.280
Peak 1.000 10.744 11.744
Image
Pre-slew 15.0-350.0 keV image (Event data)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
251.8384 27.2869 0.0061 2.9670 -20.4016 4.3500472 31.527 TRIG_00922808
Foreground time interval of the image:
-42.364 17.789 (delta_t = 60.153 [sec])
Background time interval of the image:
-447.611 -433.221 (delta_t = 14.390 [sec])
-239.912 -42.364 (delta_t = 197.548 [sec])
Lightcurves
Notes:
- 1) The mask-weighted light curves are using the flight position.
- 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)
Spectral Evolution
Spectra
Notes:
- 1) The fitting includes the systematic errors.
- 2) When the burst includes telescope slew time periods, the fitting uses an average response file made from multiple 5-s response files through out the slew time plus single time preiod for the non-slew times, and weighted by the total counts in the corresponding time period using addrmf. An average response file is needed becuase a spectral fit using 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.
Time averaged spectrum fit using the average DRM
Power-law model
Time interval is from -42.364 sec. to 53.340 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.29237 ( -0.0678052 0.0675305 )
Norm@50keV : 4.39575E-03 ( -0.000157009 0.000157009 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 48.43 using 59 PHA bins.
# Reduced chi-squared = 0.8496 for 57 degrees of freedom
# Null hypothesis probability = 7.834818e-01
Photon flux (15-150 keV) in 95.7 sec: 0.523700 ( -0.019805 0.019859 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.16526e-06 ( -1.63396e-07 1.63987e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -42.364 sec. to 53.340 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.27848 ( -0.228727 0.0702611 )
Epeak [keV] : 9966.67 ( -9999.33 -9999.33 )
Norm@50keV : 4.45959E-03 ( -0.000156537 0.000569206 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 48.72 using 59 PHA bins.
# Reduced chi-squared = 0.8701 for 56 degrees of freedom
# Null hypothesis probability = 7.441195e-01
Photon flux (15-150 keV) in 95.7 sec: 0.524663 ( -0.023963 0.021073 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.1738e-06 ( -2.00772e-07 1.79431e-07 ) ergs/cm2
Peak spectrum fit
Power-law model
Time interval is from 10.744 sec. to 11.744 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.16410 ( -0.159996 0.1591 )
Norm@50keV : 2.00376E-02 ( -0.00183121 0.00182863 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 61.18 using 59 PHA bins.
# Reduced chi-squared = 1.073 for 57 degrees of freedom
# Null hypothesis probability = 3.284157e-01
Photon flux (15-150 keV) in 1 sec: 2.34082 ( -0.21472 0.21481 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.05433e-07 ( -2.1703e-08 2.19039e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 10.744 sec. to 11.744 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.01846 ( -0.631478 0.28839 )
Epeak [keV] : 356.936 ( -356.936 -356.936 )
Norm@50keV : 2.35835E-02 ( -0.00519816 0.0230519 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 60.99 using 59 PHA bins.
# Reduced chi-squared = 1.089 for 56 degrees of freedom
# Null hypothesis probability = 3.013059e-01
Photon flux (15-150 keV) in 1 sec: 2.32787 ( -0.2208 0.22005 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.03348e-07 ( -2.34609e-08 2.25748e-08 ) ergs/cm2
Plot creation:
Wed Aug 28 18:13:52 EDT 2019