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Image
Pre-slew 15.0-350.0 keV image (Event data)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
157.5015 -5.2485 0.0191 33.0788 81.3812 1.6105041 10.026 TRIG_00449074
Foreground time interval of the image:
24.728 64.776 (delta_t = 40.048 [sec])
Background time interval of the image:
-133.499 24.728 (delta_t = 158.227 [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)
Quad-rate summed light curves (from T0-300s to T0+1000s)
The mask-weighted light curves based on cleaned DPHs
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 24.728 sec. to 64.776 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.33265 ( -0.248326 0.271473 )
Norm@50keV : 2.10710E-03 ( -0.00041114 0.000406723 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 47.95 using 59 PHA bins.
# Reduced chi-squared = 0.8413 for 57 degrees of freedom
# Null hypothesis probability = 7.977318e-01
Photon flux (15-150 keV) in 40.05 sec: 0.375042 ( -0.0451939 0.0452026 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.11485e-07 ( -1.24803e-07 1.30531e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from 24.728 sec. to 64.776 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.52556 ( -1.45708 0.767341 )
Epeak [keV] : 20.5969 ( )
Norm@50keV : 6.94226E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 46.45 using 59 PHA bins.
# Reduced chi-squared = 0.8295 for 56 degrees of freedom
# Null hypothesis probability = 8.146238e-01
Photon flux (15-150 keV) in 40.05 sec: 0.365353 ( -0.046155 0.046714 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.3656e-07 ( -1.32638e-07 1.63096e-07 ) ergs/cm2
Band function
Time interval is from 24.728 sec. to 64.776 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 4.93833 ( -4.93833 -4.93833 )
beta : -2.54210 ( -0.482361 0.323607 )
Epeak [keV] : 20.6095 ( -20.6095 3.49906 )
Norm@50keV : 1542.71 ( -184.364 4.30832e+06 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 45.40 using 59 PHA bins.
# Reduced chi-squared = 0.8254 for 55 degrees of freedom
# Null hypothesis probability = 8.187004e-01
Photon flux (15-150 keV) in 40.05 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 7.80787e-07 ( 0 0 ) ergs/cm2
Single BB
Spectral model blackbody:
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 7.51533 (-1.04471 1.19605)
R^2/D10^2 : 0.524750 (-0.235995 0.445509)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.01 using 59 PHA bins.
# Reduced chi-squared = 0.9827 for 57 degrees of freedom
# Null hypothesis probability = 5.120820e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.041e-07 4.363e-08
25- 50 3.195e-07 5.767e-08
50-150 6.800e-08 2.782e-08
15-150 5.916e-07 1.023e-07
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 36.8494 (-10.0451 15.7084)
Norm : 2.56499 (-0.573534 0.791073)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 46.50 using 59 PHA bins.
# Reduced chi-squared = 0.8159 for 57 degrees of freedom
# Null hypothesis probability = 8.382534e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.291e-07 3.384e-08
25- 50 2.905e-07 4.888e-08
50-150 2.049e-07 9.205e-08
15-150 7.245e-07 1.284e-07
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 4.47432 (-1.51313 1.85842)
R1^2/D10^2 : 3.00138 (-2.11237 4.35199)
kT2 [keV] : 13.0339 (-3.89681 11.6978)
R2^2/D10^2 : 3.75970E-02 (-0.0353397 0.144614)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 45.77 using 59 PHA bins.
# Reduced chi-squared = 0.8322 for 55 degrees of freedom
# Null hypothesis probability = 8.079316e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.377e-07 1.277e-07
25- 50 2.775e-07 1.425e-07
50-150 2.036e-07 1.244e-07
15-150 7.188e-07 3.735e-07
Peak spectrum fit
Power-law model
Time interval is from 44.204 sec. to 45.204 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.84912 ( -0.468376 0.52711 )
Norm@50keV : 8.34142E-03 ( -0.00253136 0.00232784 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.86 using 59 PHA bins.
# Reduced chi-squared = 1.050 for 57 degrees of freedom
# Null hypothesis probability = 3.724263e-01
Photon flux (15-150 keV) in 1 sec: 1.17205 ( -0.275011 0.275319 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.6698e-08 ( -2.18505e-08 2.27733e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 44.204 sec. to 45.204 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.33902 ( )
Epeak [keV] : 126.578 ( )
Norm@50keV : 4.69820E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.51 using 59 PHA bins.
# Reduced chi-squared = 1.063 for 56 degrees of freedom
# Null hypothesis probability = 3.491149e-01
Photon flux (15-150 keV) in 1 sec: 1.17396 ( -0.27843 0.27397 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.62086e-08 ( -2.13836e-08 2.29694e-08 ) ergs/cm2
Band function
Time interval is from 44.204 sec. to 45.204 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.50891 ( 1.50908 1.50908 )
beta : -1.84929 ( 1.84925 0.468858 )
Epeak [keV] : 22.9649 ( -22.8325 -22.8325 )
Norm@50keV : 1.73098E-02 ( -0.0110538 17.1347 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.86 using 59 PHA bins.
# Reduced chi-squared = 1.088 for 55 degrees of freedom
# Null hypothesis probability = 3.038996e-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] : 13.6370 (-4.41006 5.67402)
R^2/D10^2 : 0.166609 (-0.116857 0.511535)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 68.54 using 59 PHA bins.
# Reduced chi-squared = 1.202 for 57 degrees of freedom
# Null hypothesis probability = 1.408269e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 6.559e-09 3.935e-09
25- 50 2.375e-08 1.381e-08
50-150 2.869e-08 1.739e-08
15-150 5.900e-08 2.681e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 105.877 (-62.8409 -106.694)
Norm : 5.03696 (-1.41468 2.34347)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 60.88 using 59 PHA bins.
# Reduced chi-squared = 1.068 for 57 degrees of freedom
# Null hypothesis probability = 3.379806e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.316e-08 7.664e-09
25- 50 2.302e-08 1.377e-08
50-150 3.850e-08 2.832e-08
15-150 7.468e-08 4.856e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 3.47446 (-1.26149 1.86623)
R1^2/D10^2 : 31.8145 (-27.7991 413.854)
kT2 [keV] : 19.8279 (-6.17246 13.251)
R2^2/D10^2 : 3.81990E-02 (-0.0311846 0.104793)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.12 using 59 PHA bins.
# Reduced chi-squared = 1.039 for 55 degrees of freedom
# Null hypothesis probability = 3.962244e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.691e-08 9.395e-09
25- 50 1.770e-08 9.465e-09
50-150 4.189e-08 2.687e-08
15-150 7.651e-08 4.238e-08
Pre-slew spectrum (Pre-slew PHA with pre-slew DRM)
Power-law model
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.33265 ( -0.248326 0.271473 )
Norm@50keV : 2.10710E-03 ( -0.00041114 0.000406723 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 47.95 using 59 PHA bins.
# Reduced chi-squared = 0.8413 for 57 degrees of freedom
# Null hypothesis probability = 7.977318e-01
Photon flux (15-150 keV) in 40.05 sec: 0.375042 ( -0.0451939 0.0452026 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.11485e-07 ( -1.24803e-07 1.30531e-07 ) ergs/cm2
Cutoff power-law model
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.52556 ( -1.45708 0.767341 )
Epeak [keV] : 20.5969 ( )
Norm@50keV : 6.94226E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 46.45 using 59 PHA bins.
# Reduced chi-squared = 0.8295 for 56 degrees of freedom
# Null hypothesis probability = 8.146238e-01
Photon flux (15-150 keV) in 40.05 sec: 0.365353 ( -0.046155 0.046714 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.3656e-07 ( -1.32638e-07 1.63096e-07 ) ergs/cm2
Band function
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 4.93833 ( -4.93833 -4.93833 )
beta : -2.54210 ( -0.482361 0.323607 )
Epeak [keV] : 20.6095 ( -20.6095 3.49906 )
Norm@50keV : 1542.71 ( -184.364 4.30832e+06 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 45.40 using 59 PHA bins.
# Reduced chi-squared = 0.8254 for 55 degrees of freedom
# Null hypothesis probability = 8.187004e-01
Photon flux (15-150 keV) in 40.05 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 7.80787e-07 ( 0 0 ) ergs/cm2
S(25-50 keV) vs. S(50-100 keV) plot
S(25-50 keV) = 2.63e-07
S(50-100 keV) = 2.09e-07
T90 vs. Hardness ratio plot
T90 = 35.1360000371933 sec.
Hardness ratio (energy fluence ratio) = 0.794677
Color vs. Color plot
Count Ratio (25-50 keV) / (15-25 keV) = 0.860975
Count Ratio (50-100 keV) / (15-25 keV) = 0.29292
Mask shadow pattern
IMX = 9.761395287750096E-02, IMY = -6.440098545552502E-01
TIME vs. PHA plot around the trigger time
TIME vs. DetID plot around the trigger time
100 us light curve (15-350 keV)
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:
-133.499410 24.728000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
135.5276 -40.5328 1.3 17.0 -23.1 1.4418 8.7 1.3 Vela X-1
170.1533 -60.6159 5.2 23.7 -114.4 0.4225 2.2 4.8 Cen X-3
186.4957 -62.7335 5.1 30.1 -125.2 0.5056 2.3 4.9 GX 301-2
189.9443 -7.6090 2.6 42.5 133.4 2.3863 4.4 ------ UNKNOWN
132.1855 -18.8571 2.4 29.3 25.7 0.9258 4.9 ------ UNKNOWN
209.2856 -31.3967 2.4 42.6 178.2 1.3703 4.8 ------ UNKNOWN
165.2340 -41.9674 2.4 7.0 -155.0 0.7211 4.8 ------ UNKNOWN
116.8714 -28.4762 2.7 34.9 -4.8 0.8645 4.2 ------ UNKNOWN
105.9640 -26.0590 2.6 44.6 -8.6 1.1784 4.5 ------ UNKNOWN
138.6884 -61.7681 2.8 26.1 -78.6 0.8748 4.2 ------ UNKNOWN
234.4169 -40.6506 2.9 57.5 -160.1 3.3889 3.9 ------ UNKNOWN
87.9354 -26.6532 2.6 58.4 -19.5 4.0303 4.5 ------ UNKNOWN
85.0375 -30.0422 2.9 58.9 -24.4 4.9576 4.0 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image:
24.728000 64.776000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
135.4650 -40.4428 3.2 17.0 -22.8 -0.2734 -3.6 7.3 Vela X-1
170.1703 -60.6978 8.7 23.8 -114.4 -0.1149 -1.3 6.2 Cen X-3
186.3478 -62.7582 10.7 30.0 -125.1 -0.1101 -1.1 8.5 GX 301-2
157.5015 -5.2485 1.1 33.1 81.4 1.6101 10.0 ------ UNKNOWN
174.8128 -20.7926 2.0 23.1 126.7 0.5455 5.8 ------ UNKNOWN
158.8245 -63.2338 2.1 24.9 -100.3 0.5138 5.4 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image:
146.700650 963.160000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
135.5021 -40.5318 1.1 40.4 -124.5 9.3784 10.1 1.8 Vela X-1
170.2574 -60.6358 17.7 56.2 -158.0 -1.4477 -0.6 1.9 Cen X-3
155.5829 -35.6594 2.5 30.5 -147.5 2.3892 4.7 ------ UNKNOWN
148.6460 -60.0888 4.0 55.3 -145.2 9.2846 2.9 ------ UNKNOWN
Plot creation:
Sat May 30 22:47:55 EDT 2015