Analysis for Ground-detected GRB: Trigger=778019
Analysis Summary
Notes:
- 1) No attempt has been made to eliminate the non-significant decimal places.
- 2) This is a special analysis for ground-detected GRB. The event data duration is likely to be shorter than the burst duration. In such cases, the burst durations are found using the quad-rate data, and spectral analyses are only available for event data range.
- 3) Some mask-weighted light curve plots might be missing because the time range is not completely covered by the event data range.
==========================================================================
BAT GROUND-DETECTED GRB DATA PROCESSING REPORT
Process Script Ver: batgrbproduct v2.46
Process Start Time: Wed Oct 11 13:10:39 EDT 2017
Host Name: bat1
Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/ground_detect_bursts/scripts
======================================================================
Trigger: 00778019 Segment: 000
BAT Trigger Time: 529361984.0
UTC: 2017-10-10T20:59:24.168 [includes UTCF correction]
Where From?: Ground analysis (best_duration.txt)
NOTE: BAT trigger time for ground-detected burst is the T100 start time.
Analysis Position: [ source = GCN ]
RA: 34.1224 Dec: -54.4044 [deg; J2000]
Refined Position: [ source = BAT pre-slew image ]
RA: 34.123266452 Dec: -54.4101842469 [deg; J2000]
{ 02h 16m 29.6s , -54d -24' -36.7" }
+/- 1.58230542526 [arcmin] (estimated 90% radius based on SNR)
SNR: 15.7933676234
Angular difference between the GCN position (ra=34.1224, dec=-54.4044 deg) and this refined position is 0.348 arcmin
Partial Coding Fraction: 0.7109375 [ including projection effects ]
Duration
T90: 30.4000000357628 +/- 1.6
Measured from: 0
to: 30.4 [s; relative to TRIGTIME]
T50: 17.6000000238419 +/- 1.6
Measured from: 6.4
to: 24 [s; relative to TRIGTIME]
=== 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 4.74e-08 9.23e-08 1.39e-07 4.57e-07 3.91e-07 7.37e-07 erg/cm2
Error 8.17e-09 9.80e-09 1.87e-08 1.31e-07 4.57e-08 1.46e-07 erg/cm2
Peak flux Power-law -------- -------- -------- -------- -------- -------- ph/cm2/s
Error -------- -------- -------- -------- -------- -------- ph/cm2/s
Fluence Cutoff-PL 4.13e-08 9.96e-08 1.46e-07 1.61e-07 3.68e-07 4.48e-07 erg/cm2
Error 1.01e-08 1.24e-08 2.10e-08 1.84e-07 5.06e-08 1.89e-07 erg/cm2
Peak flux Cutoff-PL -------- -------- -------- -------- -------- -------- ph/cm2/s
Error -------- -------- -------- -------- -------- -------- 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 1.405 0.176 - - 4.02e-03 4.17e-04 52.390 57
CPL 0.618 0.845 88.2 286.6 9.97e-03 0.00e+00 49.240 56
(1-s peak spectrum is not available)
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
=== Table of the duration information ==
Value tstart tstop
T100 32.000 0.000 32.000
T90 30.400 0.000 30.400
T50 17.600 6.400 24.000
Peak 1.000 0.300 1.300
Image
15.0-350.0 keV image (Event data)
#RAcent DECcent POSerr Theta Phi Peak_Cts SNR Name
34.123 -54.410 0.012 20.533 110.178 0.580 15.793 TRIG_00778019
Image time interval: 2.300 to 11.089 [sec]
Lightcurves
Notes:
- 1) The mask-weighted lightcurves have units of either count/det or counts/sec/det, where a det is 0.4 x 0.4 = 0.16 sq cm.
- 2) 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 (for the best duration plot, slew times are marked by green arrows).
- 3) For lightcurves in unit of count rate, time of each bin is in the middle of the bin.
Best duration plot
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
(Plot unavailable, possibly because there are no event data in this time range.)
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) 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 1.000 sec. to 11.088 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.40520 ( -0.17501 0.176344 )
Norm@50keV : 4.02355E-03 ( -0.000417721 0.000415744 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 52.39 using 59 PHA bins.
# Reduced chi-squared = 0.9191 for 57 degrees of freedom
# Null hypothesis probability = 6.485389e-01
Photon flux (15-150 keV) in 10.09 sec: 0.490583 ( -0.050104 0.050152 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.91915e-07 ( -4.54484e-08 4.60117e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 1.000 sec. to 11.088 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.617615 ( -0.931877 0.757798 )
Epeak [keV] : 88.2368 ( -24.2328 549.017 )
Norm@50keV : 9.96570E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 49.24 using 59 PHA bins.
# Reduced chi-squared = 0.8793 for 56 degrees of freedom
# Null hypothesis probability = 7.266063e-01
Photon flux (15-150 keV) in 10.09 sec: 0.473018 ( -0.05344 0.053104 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.68495e-07 ( -5.00083e-08 5.11492e-08 ) ergs/cm2
Band function
Time interval is from 1.000 sec. to 11.088 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : ( )
beta : ( )
Epeak [keV] : ( )
Norm@50keV : ( )
------------------------------------------------------------
Photon flux (15-150 keV) in 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] : 15.8376 (-1.76678 2.05105)
R^2/D10^2 : 4.78461E-02 (-0.0164414 0.0241918)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.21 using 59 PHA bins.
# Reduced chi-squared = 1.039 for 57 degrees of freedom
# Null hypothesis probability = 3.948527e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.509e-08 4.646e-09
25- 50 1.047e-07 1.405e-08
50-150 1.828e-07 3.456e-08
15-150 3.125e-07 4.213e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 200.000 (-51.4786 -200)
Norm : 2.00929 (-0.203519 0.203519)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 52.40 using 59 PHA bins.
# Reduced chi-squared = 0.9192 for 57 degrees of freedom
# Null hypothesis probability = 6.481932e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 5.071e-08 2.792e-08
25- 50 9.755e-08 5.005e-08
50-150 2.139e-07 1.156e-07
15-150 3.622e-07 1.825e-07
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 3.66247 (-1.45872 2.43033)
R1^2/D10^2 : 4.52892 (-4.03335 42.9446)
kT2 [keV] : 18.4282 (-2.55608 3.64342)
R2^2/D10^2 : 2.64178E-02 (-0.0128517 0.0152486)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 46.74 using 59 PHA bins.
# Reduced chi-squared = 0.8498 for 55 degrees of freedom
# Null hypothesis probability = 7.783272e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 4.465e-08 1.848e-08
25- 50 9.206e-08 2.196e-08
50-150 2.099e-07 5.787e-08
15-150 3.466e-07 7.401e-08
Webpage updated on:
Wed Oct 11 13:39:06 EDT 2017