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.
======================================================================
BAT GRB EVENT DATA PROCESSING REPORT
Process Script Ver: batgrbproduct v2.46
Process Start Time: Wed Jan 22 19:05:41 EST 2014
Host Name: batevent1
Current Working Dir: /local/data/batevent/batevent_reproc/trigger176620
======================================================================
Trigger: 00176620 Segment: 000
BAT Trigger Time: 158518482.176 [s; MET]
Trigger Stop: 158518490.368 [s; MET]
UTC: 2006-01-09T16:54:41.230260 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 282.709997814732 Dec: 31.9895994348777 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 7.1
Image Trigger?: NO
Rate S/N Ratio: 10.9087121146357 [ if not an image trigger ]
Image S/N Ratio: 7.1
Analysis Position: [ source = BAT ]
RA: 282.709997814732 Dec: 31.9895994348777 [deg; J2000]
Refined Position: [ source = BAT pre-slew burst ]
RA: 282.71 Dec: 31.9896 [deg; J2000]
{ 18h 50m 50.4s , +31d 59' 22.6" }
+/- 2.60540488989 [arcmin] (estimated 90% radius based on SNR)
SNR: 7.74582596529
Angular difference between the analysis and refined position is 0.000116 arcmin
Partial Coding Fraction: 0.921875 [ including projection effects ]
Duration
T90: 115.592000007629 +/- 11.1491641034503
Measured from: 1.46000000834465
to: 117.052000015974 [s; relative to TRIGTIME]
T50: 83.3160000145435 +/- 17.4548271706558
Measured from: 12.4000000059605
to: 95.716000020504 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 90.1840000152588
to: 91.1840000152588 [s; relative to TRIGTIME]
Total Fluence
Measured from: -1.96799999475479
to: 126.768000006676 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.406310 0.508545 0.273427 0.038994
0.055023 0.056339 0.048130 0.040655 [error]
Peak 0.014924 0.024784 0.015563 0.007916
0.004996 0.005130 0.004463 0.003548 [error]
[ fluence units of on-axis counts / fully illuminated detector ]
======================================================================
====== Table of the duration information =============================
Value tstart tstop
T100 128.736 -1.968 126.768
T90 115.592 1.460 117.052
T50 83.316 12.400 95.716
Peak 1.000 90.184 91.184
====== Spectral Analysis Summary =====================================
Model : spectral model: simple power-law (PL) and cutoff power-law (CPL)
Ph_index : photon index: E^{Ph_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 both the PL model and CPL model
Nomr_90err : 90% error of the normalization
chi2 : Chi-Squared
dof : degree of freedo
=== Time-averaged spectral analysis ===
(Best model with acceptable fit: PL)
Model Ph_index Ph_90err_low Ph_90err_hi Epeak Epeak_90err_low Epeak_90err_hi Norm Nomr_90err_low Norm_90err_hi chi2 dof
PL -1.889 -0.243 0.228 - - - 5.58e-04 -8.95e-05 8.71e-05 41.770 57
CPL -1.307 -0.863 1.101 50.217 -40.462 -50.217 1.21e-03 -1.21e-03 4.09e-03 40.500 56
=== 1-s peak spectral analysis ===
(Best model with acceptable fit: PL)
Model Ph_index Ph_90err_low Ph_90err_hi Epeak Epeak_90err_low Epeak_90err_hi Norm Nomr_90err_low Norm_90err_hi chi2 dof
PL -1.555 -0.415 0.397 - - - 3.63e-03 -9.61e-04 9.42e-04 49.160 57
CPL -0.269 -1.484 2.579 62.164 -18.138 -62.164 1.78e-02 -1.78e-02 4.10e-01 47.440 56
=== 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 PL 1.32e-07 1.92e-07 2.07e-07 4.17e-07 6.60e-07 9.49e-07 erg/cm2
90%_error_low -2.33e-08 -2.45e-08 -4.44e-08 -1.54e-07 -1.02e-07 -2.08e-07 erg/cm2
90%_error_hi 2.40e-08 2.45e-08 4.53e-08 2.04e-07 1.05e-07 2.48e-07 erg/cm2
Peak flux PL 1.57e-01 1.53e-01 1.04e-01 1.12e-01 4.60e-01 5.27e-01 ph/cm2/s
90%_error_low -5.66e-02 -3.86e-02 -3.42e-02 -5.78e-02 -1.13e-01 -1.32e-01 ph/cm2/s
90%_error_hi 6.15e-02 3.83e-02 3.43e-02 8.59e-02 1.13e-01 1.35e-01 ph/cm2/s
Fluence CPL 1.26e-07 2.06e-07 2.03e-07 1.56e-07 6.21e-07 6.91e-07 erg/cm2
90%_error_low -2.59e-08 -3.11e-08 -5.27e-08 -1.20e-07 -1.13e-07 -1.72e-07 erg/cm2
90%_error_hi 2.59e-08 3.41e-08 4.95e-08 3.69e-07 1.19e-07 3.55e-07 erg/cm2
Peak flux CPL 1.32e-01 1.76e-01 1.10e-01 3.05e-02 4.41e-01 4.48e-01 ph/cm2/s
90%_error_low -6.69e-02 -4.88e-02 -4.26e-02 -3.05e-02 -1.16e-01 -1.21e-01 ph/cm2/s
90%_error_hi 7.04e-02 5.30e-02 4.11e-02 1.10e-01 1.16e-01 1.58e-01 ph/cm2/s
======================================================================
Image
Pre-slew 15.0-50.0 keV image (Event data)
#RAcent DECcent POSerr Theta Phi Peak_Cts SNR Name 282.710 31.990 0.000 18.273 -44.240 0.163 7.746 TRIG_00176620 Image time interval: 0.000 to 8.192 [sec]
Light Curves
Note: 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.
Full-time range; 1 s binning
Other quick-look light curves:
- 64 ms binning (zoomed)
- 16 ms binning (zoomed)
- 8 ms binning (zoomed)
- 2 ms binning (zoomed)
- SN=5 or 10 s binning (full-time range)
- Raw light curve
Spectra
- 64 ms binning (zoomed)
- 16 ms binning (zoomed)
- 8 ms binning (zoomed)
- 2 ms binning (zoomed)
- SN=5 or 10 s binning (full-time range)
- Raw light curve
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 -1.968 sec. to 126.768 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.88922 ( -0.242888 0.228046 ) Norm@50keV : 5.57795E-04 ( -8.94779e-05 8.70886e-05 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 41.77 using 59 PHA bins. # Reduced chi-squared = 0.7329 for 57 degrees of freedom # Null hypothesis probability = 9.349251e-01 Photon flux (15-150 keV) in 128.7 sec: 7.96904E-02 ( -0.0101109 0.0101113 ) ph/cm2/s Energy fluence (15-150 keV) : 6.60068e-07 ( -1.02499e-07 1.05262e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -1.968 sec. to 126.768 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.30705 ( -0.863022 1.10097 ) Epeak [keV] : 50.2172 ( -40.4617 -50.2172 ) Norm@50keV : 1.20671E-03 ( -0.00120671 0.00409062 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 40.50 using 59 PHA bins. # Reduced chi-squared = 0.7232 for 56 degrees of freedom # Null hypothesis probability = 9.409184e-01 Photon flux (15-150 keV) in 128.7 sec: 7.80758E-02 ( -0.010367 0.0103804 ) ph/cm2/s Energy fluence (15-150 keV) : 6.21425e-07 ( -1.12905e-07 1.19098e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 90.184 sec. to 91.184 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.55475 ( -0.414946 0.396908 ) Norm@50keV : 3.62834E-03 ( -0.000961393 0.000942157 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 49.16 using 59 PHA bins. # Reduced chi-squared = 0.8625 for 57 degrees of freedom # Null hypothesis probability = 7.604141e-01 Photon flux (15-150 keV) in 1 sec: 0.459976 ( -0.113078 0.113166 ) ph/cm2/s Energy fluence (15-150 keV) : 3.41382e-08 ( -9.57019e-09 9.89903e-09 ) ergs/cm2
Cutoff power-law model
Time interval is from 90.184 sec. to 91.184 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -0.268648 ( -1.48401 2.57924 ) Epeak [keV] : 62.1642 ( -18.1379 -62.1642 ) Norm@50keV : 1.78182E-02 ( -0.0178182 0.410401 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 47.44 using 59 PHA bins. # Reduced chi-squared = 0.8472 for 56 degrees of freedom # Null hypothesis probability = 7.852857e-01 Photon flux (15-150 keV) in 1 sec: 0.441307 ( -0.115577 0.115816 ) ph/cm2/s Energy fluence (15-150 keV) : 3.08021e-08 ( -9.60971e-09 1.07392e-08 ) ergs/cm2
Time-resolved spectra
Distribution
T90 vs. Hardness ratio plot
T90 = 115.592 sec. Hardness ratio (energy fluence ratio) = 1.07986635601
S(15-50 keV) vs. S(50-150 keV) plot
S(15-50 keV) = 3.241191e-07 S(50-150 keV) = 3.359468e-07
The dash-dotted line and the dashed line traces the fluences calculated from the Band function with Epeak = 15 and 150 keV, respectively. Both lines assume a canonical values of alpha = -1 and beta = -2.5.
Mask shadow pattern
IMX = 0.236553484601, IMY = 0.230361441268
Spacecraft aspect plot
Bright source in the pre-burst/pre-slew/post-slew images
Pre-burst image of 15-350 keV band
Time interval of the image: -299.176000 -1.968000 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 254.3190 35.4066 5.0 33.9 -0.9 0.6028 2.3 7.8 Her X-1 288.8076 10.9863 2.2 36.1 -73.3 2.7361 5.2 2.5 GRS 1915+105 299.5946 35.1969 0.2 11.2 -96.8 12.1903 61.3 0.4 Cyg X-1 308.1361 40.9574 1.1 9.4 -146.8 2.2466 10.1 1.2 Cyg X-3 326.0702 38.2469 5.8 22.5 -167.1 0.4380 2.0 6.6 Cyg X-2 245.1290 27.8874 2.4 44.7 -3.3 1.8280 4.8 ------ UNKNOWN 322.7690 31.8934 2.7 24.2 -150.2 0.8818 4.3 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image: -1.968000 50.324600 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 254.3714 35.1700 8.0 34.0 -1.3 -0.1388 -1.4 11.2 Her X-1 288.7794 10.9640 217.5 36.1 -73.2 -0.0081 -0.1 1.6 GRS 1915+105 299.6132 35.2059 13.5 11.2 -96.8 0.0570 0.9 1.1 Cyg X-1 307.9142 40.9739 5.4 9.2 -146.3 0.1425 2.1 9.0 Cyg X-3 326.1592 38.2582 7.7 22.5 -167.2 0.1099 1.5 3.9 Cyg X-2 3.1404 32.6733 2.5 51.0 173.1 0.8927 4.7 ------ UNKNOWN 282.7250 32.0169 1.8 18.2 -44.2 0.4560 6.3 ------ UNKNOWN 0.5850 18.4030 2.5 58.4 -171.6 1.8084 4.7 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image: 89.724600 302.935500 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 254.3107 35.4136 5.9 23.8 25.4 -0.3286 -2.0 8.4 Her X-1 268.4111 -1.4264 6.3 36.1 -55.9 0.5278 1.8 3.0 SW J1753.5-0127 288.8187 10.9604 1.0 21.8 -97.0 2.1556 12.2 1.5 GRS 1915+105 299.5894 35.2006 0.2 14.4 171.9 9.0743 62.7 0.1 Cyg X-1 308.0797 40.9569 1.3 22.2 158.4 1.5242 8.8 1.4 Cyg X-3 326.1803 38.1885 6.2 35.8 167.0 0.4388 1.9 8.0 Cyg X-2 299.2917 70.8156 2.1 39.9 107.7 3.3849 5.6 ------ UNKNOWN 315.8876 -3.7829 2.0 47.7 -128.3 4.2203 5.9 ------ UNKNOWN