batgrbproduct Analysis for Trigger=208050
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 page will be updated for up to 8 downlinks after the trigger.
======================================================================
BAT GRB EVENT DATA PROCESSING REPORT
Process Script Ver: batgrbproduct v2.41
Process Start Time (local time): Mon Dec 31 21:02:11 EST 2007
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger208050/GCN5_download_cron
======================================================================
Trigger: 00208050 Segment: 000
BAT Trigger Time: 168164100.032 [s; MET]
Trigger Stop: 168164101.056 [s; MET]
UTC: 2006-05-01T08:14:58.865920 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 328.367202913993 Dec: 43.9831881862281 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 11.15
Image Trigger?: NO
Rate S/N Ratio: 23.3023603954621 [ if not an image trigger ]
Image S/N Ratio: 11.15
Flight Position: [ source = BAT ]
RA: 328.367202913993 Dec: 43.9831881862281 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 328.370915035877 Dec: 43.9994786381414 [deg; J2000]
{ 21h 53m 29.0s , +43d 59' 58.1" }
+/- 1.35508372763992 [arcmin] (estimated 90% radius based on SNR)
+/- 0.468610625719666 [arcmin] (formal 1-sigma fit error)
SNR: 19.7058574547129
RA = 21h 53m 29.0s (328.370915 deg.)
Dec = 43d 59' 58" (43.999479 deg.)
Angular difference between Flight and Ground position is 0.990475 arcmin
Partial Coding Fraction: 0.3671875 [ including projection effects ]
Duration
T90: 21.8759999871254 +/- 4.78632594694618
Measured from: -0.659999996423721
to: 21.2159999907017 [s; relative to TRIGTIME]
T50: 7.06000000238419 +/- 1.36816958109932
Measured from: 0.972000002861023
to: 8.03200000524521 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 0.363999992609024
to: 1.36399999260902 [s; relative to TRIGTIME]
Total Fluence
Measured from: -1.27599999308586
to: 25.9560000002384 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.429666 0.652315 0.518466 0.157062
0.046031 0.047811 0.043412 0.037934 [error]
Peak 0.042397 0.082303 0.095582 0.025471
0.009267 0.010316 0.010004 0.007940 [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 1.56e-07 2.94e-07 4.30e-07 1.34e-06 1.22e-06 2.21e-06 erg/cm2
Error 2.42e-08 2.72e-08 4.15e-08 2.90e-07 1.03e-07 3.14e-07 erg/cm2
Peak flux Power-law 4.42e-01 6.04e-01 5.97e-01 1.08e+00 1.99e+00 2.71e+00 ph/cm2/s
Error 1.14e-01 8.77e-02 7.37e-02 2.75e-01 2.42e-01 3.38e-01 ph/cm2/s
Fluence Cutoff-PL 1.47e-07 2.99e-07 4.42e-07 1.01e-06 1.21e-06 1.88e-06 erg/cm2
Error 3.02e-08 3.11e-08 4.89e-08 5.44e-07 7.94e-08 5.51e-07 erg/cm2
Peak flux Cutoff-PL 3.71e-01 5.99e-01 6.42e-01 7.55e-01 1.95e+00 2.36e+00 ph/cm2/s
Error 1.96e-01 1.12e-01 1.05e-01 3.92e-01 2.75e-01 5.03e-01 ph/cm2/s
Fluence Band 1.46e-07 2.99e-07 4.41e-07 1.01e-06 1.21e-06 1.92e-06 erg/cm2
Error 2.99e-08 3.02e-08 4.99e-08 5.44e-07 1.07e-07 5.50e-07 erg/cm2
Peak flux Band 3.71e-01 5.99e-01 6.42e-01 7.55e-01 1.95e+00 2.37e+00 ph/cm2/s
Error 1.60e-01 1.12e-01 1.05e-01 4.42e-01 2.76e-01 5.24e-01 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.453 0.144 - - 4.68e-03 3.75e-04 56.345 57
CPL 1.171 0.489 164.0 5000.0 6.27e-03 5.62e-03 55.887 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.000 0.216 - - 1.72e-02 2.26e-03 62.046 57
CPL 0.501 0.823 195.8 5000.0 2.70e-02 2.38e-02 60.997 0
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: 11.072000 sec.
T50 in the 50-300 keV band: 4.544000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 27.232 -1.276 25.956
T90 21.876 -0.660 21.216
T50 7.060 0.972 8.032
Peak 1.000 0.364 1.364
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
328.3709 +43.9995 0.0098 47.7 -170.2 1.7745 19.7 TRIG_00208050
------------------------------------------
Foreground time interval of the image:
-1.276 25.956 (delta_t = 27.232 [sec])
Background time interval of the image:
-204.731 -192.192 (delta_t = 12.539 [sec])
-191.032 -1.276 (delta_t = 189.756 [sec])
Lightcurves
Notes:
- 1) All plots contain as much data as has been downloaded to date.
- 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)
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.
Time averaged spectrum fit using the pre-slew DRM
Power-law model
Time interval is from -1.276 sec. to 25.956 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.45306 ( -0.144008 0.143750 )
Norm@50keV : 4.678620E-03 ( -3.751968E-04 3.751907E-04) )
------------------------------------------------------------
Chi-Squared = 56.34495 using 59 PHA bins.
Reduced chi-squared = 0.9885079 for 57 degrees of freedom
Null hypothesis probability = 0.500
Photon flux (15-150 keV) in 27.23 sec: 0.577013 ( -0.050325 0.050557 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.21851e-06 ( -1.03085e-07 1.0318e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -1.276 sec. to 25.956 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.17082 ( -0.567481 0.411191 )
Epeak [keV] : 164.004 ( -163.994 9836.00 )
Norm@50keV : 6.271798E-03 ( -6.271799E-03 4.965201E-03) )
------------------------------------------------------------
Chi-Squared = 55.88731 using 59 PHA bins.
Reduced chi-squared = 0.9979876 for 56 degrees of freedom
Null hypothesis probability = 0.479
Photon flux (15-150 keV) in 27.23 sec: 0.570459 ( -0.052557 0.05268 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.20948e-06 ( -5.36186e-08 1.05268e-07 ) ergs/cm2
Band function
Time interval is from -1.276 sec. to 25.956 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.11293 ( -8.88707 2.24008 )
beta : -1.54208 ( -7.45712 1.22001 )
Epeak [keV] : 119.436 ( -167.385 9832.51 )
Norm@50keV : 7.035808E-03 ( -1.904217E-03 2.879261E-02) )
------------------------------------------------------------
Chi-Squared = 56.21618 using 59 PHA bins.
Reduced chi-squared = 1.022112 for 55 degrees of freedom
Null hypothesis probability = 0.429
Photon flux (15-150 keV) in 27.23 sec: 0.570422 ( -0.052627 0.05268 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.20833e-06 ( -1.0697e-07 1.06053e-07 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 0.364 sec. to 1.364 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.999826 ( -0.220993 0.210544 )
Norm@50keV : 1.721254E-02 ( -2.282525E-03 2.242737E-03) )
------------------------------------------------------------
Chi-Squared = 62.04604 using 59 PHA bins.
Reduced chi-squared = 1.088527 for 57 degrees of freedom
Null hypothesis probability = 0.301
Photon flux (15-150 keV) in 1.000 sec: 1.98974 ( -0.24171 0.2415 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.85872e-07 ( -2.2686e-08 2.3262e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.364 sec. to 1.364 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.501388 ( -1.02050 0.625465 )
Epeak [keV] : 195.767 ( -195.757 9804.23 )
Norm@50keV : 2.704755E-02 ( -1.153612E-02 3.607552E-02) )
------------------------------------------------------------
Chi-Squared = 60.99673 using 59 PHA bins.
but latest trial 1.12685 gives Chi-Squared = 6.12428
Reduced chi-squared = 1.089227 for 56 degrees of freedom
Null hypothesis probability = 0.301
Photon flux (15-150 keV) in 1.000 sec: 1.94529 ( -0.2746 0.27588 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.86315e-07 ( -2.3497e-08 2.3316e-08 ) ergs/cm2
Band function
Time interval is from 0.364 sec. to 1.364 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.612621 ( -9.38738 5.61262 )
beta : -1.01921 ( -7.30137 1.86797 )
Epeak [keV] : 122.252 ( -195.604 9804.30 )
Norm@50keV : 2.996126E-02 ( -1.154503E-02 499595. )
------------------------------------------------------------
Chi-Squared = 61.93612 using 59 PHA bins.
Reduced chi-squared = 1.126111 for 55 degrees of freedom
Null hypothesis probability = 0.242
Photon flux (15-150 keV) in 1.000 sec: 1.94540 ( -0.27477 0.27651 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.86221e-07 ( -2.3463e-08 2.3369e-08 ) ergs/cm2
Plot creation:
Mon Dec 31 21:19:36 EST 2007