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Image
Pre-slew 15.0-350.0 keV image (Event data)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
236.9576 20.5593 0.0169 14.6358 -17.8866 1.2366684 11.358 TRIG_00313116
Foreground time interval of the image:
-28.264 58.608 (delta_t = 86.872 [sec])
Background time interval of the image:
-239.000 -28.264 (delta_t = 210.736 [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)
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 -28.264 sec. to 58.608 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.67837 ( -0.170711 0.174371 )
Norm@50keV : 9.79447E-04 ( -0.000105239 0.000103788 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 65.35 using 59 PHA bins.
# Reduced chi-squared = 1.147 for 57 degrees of freedom
# Null hypothesis probability = 2.092736e-01
Photon flux (15-150 keV) in 86.87 sec: 0.129114 ( -0.0124104 0.0124162 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.8921e-07 ( -8.92555e-08 9.08556e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -28.264 sec. to 58.608 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.19341 ( -0.834717 0.599365 )
Epeak [keV] : 72.3010 ( -22.2543 -72.3238 )
Norm@50keV : 1.83543E-03 ( -0.000925941 0.00360125 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 63.92 using 59 PHA bins.
# Reduced chi-squared = 1.141 for 56 degrees of freedom
# Null hypothesis probability = 2.182364e-01
Photon flux (15-150 keV) in 86.87 sec: 0.126301 ( -0.013065 0.013026 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.44185e-07 ( -1.08819e-07 1.10688e-07 ) ergs/cm2
Band function
Time interval is from -28.264 sec. to 58.608 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 4.90586 ( -5.6538 -4.90586 )
beta : -1.91184 ( -0.297723 0.227942 )
Epeak [keV] : 26.6771 ( -3.95588 3.68342 )
Norm@50keV : 72.2442 ( -6.83173 235.914 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.46 using 59 PHA bins.
# Reduced chi-squared = 1.081 for 55 degrees of freedom
# Null hypothesis probability = 3.164834e-01
Photon flux (15-150 keV) in 86.87 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] : 11.2743 (-1.27497 1.50331)
R^2/D10^2 : 3.91881E-02 (-0.0145046 0.0220389)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 81.77 using 59 PHA bins.
# Reduced chi-squared = 1.435 for 57 degrees of freedom
# Null hypothesis probability = 1.741063e-02
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 9.082e-08 1.577e-08
25- 50 2.650e-07 3.340e-08
50-150 1.938e-07 4.708e-08
15-150 5.496e-07 6.633e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 128.583 (-45.1773 -127.252)
Norm : 0.542377 (-0.0609734 0.0795364)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 63.88 using 59 PHA bins.
# Reduced chi-squared = 1.121 for 57 degrees of freedom
# Null hypothesis probability = 2.476834e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.223e-07 1.603e-08
25- 50 2.214e-07 4.717e-08
50-150 4.084e-07 2.090e-07
15-150 7.521e-07 2.726e-07
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 7.94494 (-1.72219 1.74305)
R1^2/D10^2 : 0.111465 (-0.0521615 0.105401)
kT2 [keV] : 33.6922 (-13.625 95.625)
R2^2/D10^2 : 5.23904E-04 (-0.000485131 0.00255851)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.94 using 59 PHA bins.
# Reduced chi-squared = 1.090 for 55 degrees of freedom
# Null hypothesis probability = 3.012577e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.175e-07 4.019e-08
25- 50 2.386e-07 8.044e-08
50-150 4.164e-07 2.160e-07
15-150 7.724e-07 3.123e-07
Peak spectrum fit
Power-law model
Time interval is from -3.036 sec. to -2.036 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.29316 ( -0.54009 0.530692 )
Norm@50keV : 3.18315E-03 ( -0.00091106 0.000909732 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 35.89 using 59 PHA bins.
# Reduced chi-squared = 0.6297 for 57 degrees of freedom
# Null hypothesis probability = 9.870544e-01
Photon flux (15-150 keV) in 1 sec: 0.379283 ( -0.110815 0.111602 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.1508e-08 ( -9.98913e-09 1.02676e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -3.036 sec. to -2.036 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.22955 ( -2.50685 0.886866 )
Epeak [keV] : 626.793 ( )
Norm@50keV : 3.41467E-03 ( -0.00116103 0.0578652 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 35.88 using 59 PHA bins.
# Reduced chi-squared = 0.6407 for 56 degrees of freedom
# Null hypothesis probability = 9.833212e-01
Photon flux (15-150 keV) in 1 sec: 0.376469 ( -0.116797 0.113552 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.11904e-08 ( -1.09487e-08 1.05302e-08 ) ergs/cm2
Band function
Time interval is from -3.036 sec. to -2.036 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.926297 ( 0.920341 0.920341 )
beta : -1.30113 ( 1.30193 0.547098 )
Epeak [keV] : 73.4066 ( -70.5085 -70.5085 )
Norm@50keV : 5.96244E-03 ( -0.00389715 0 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 35.89 using 59 PHA bins.
# Reduced chi-squared = 0.6525 for 55 degrees of freedom
# Null hypothesis probability = 9.785628e-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] : 18.2161 (-6.09217 9.99425)
R^2/D10^2 : 2.29180E-02 (-0.022885 0.0669983)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 38.44 using 59 PHA bins.
# Reduced chi-squared = 0.6744 for 57 degrees of freedom
# Null hypothesis probability = 9.718942e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.517e-09 9.553e-10
25- 50 7.077e-09 4.219e-09
50-150 1.710e-08 1.149e-08
15-150 2.569e-08 1.567e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 199.363 (-116.219 -199.363)
Norm : 1.56811 (-0.451712 0.451723)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 36.60 using 59 PHA bins.
# Reduced chi-squared = 0.6422 for 57 degrees of freedom
# Null hypothesis probability = 9.837193e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 3.905e-09 2.443e-09
25- 50 7.511e-09 4.521e-09
50-150 1.647e-08 1.011e-08
15-150 2.789e-08 1.684e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 5.85439 (-5.85712 -5.85712)
R1^2/D10^2 : 0.605746 (-0.604416 -0.604416)
kT2 [keV] : 25.6088 (-10.966 -25.6182)
R2^2/D10^2 : 6.50601E-03 (-0.00649728 0.0391089)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 35.87 using 59 PHA bins.
# Reduced chi-squared = 0.6522 for 55 degrees of freedom
# Null hypothesis probability = 9.786550e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 3.392e-09 2.131e-09
25- 50 6.715e-09 3.392e-09
50-150 2.056e-08 1.199e-08
15-150 3.067e-08 1.801e-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: 1.67837 ( -0.170711 0.174371 )
Norm@50keV : 9.79447E-04 ( -0.000105239 0.000103788 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 65.35 using 59 PHA bins.
# Reduced chi-squared = 1.147 for 57 degrees of freedom
# Null hypothesis probability = 2.092736e-01
Photon flux (15-150 keV) in 86.87 sec: 0.129114 ( -0.0124104 0.0124162 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.8921e-07 ( -8.92555e-08 9.08556e-08 ) ergs/cm2
Cutoff power-law model
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.19341 ( -0.834717 0.599365 )
Epeak [keV] : 72.3010 ( -22.2543 -72.3238 )
Norm@50keV : 1.83543E-03 ( -0.000925941 0.00360125 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 63.92 using 59 PHA bins.
# Reduced chi-squared = 1.141 for 56 degrees of freedom
# Null hypothesis probability = 2.182364e-01
Photon flux (15-150 keV) in 86.87 sec: 0.126301 ( -0.013065 0.013026 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.44185e-07 ( -1.08819e-07 1.10688e-07 ) ergs/cm2
Band function
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 4.90586 ( -5.6538 -4.90586 )
beta : -1.91184 ( -0.297723 0.227942 )
Epeak [keV] : 26.6771 ( -3.95588 3.68342 )
Norm@50keV : 72.2442 ( -6.83173 235.914 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.46 using 59 PHA bins.
# Reduced chi-squared = 1.081 for 55 degrees of freedom
# Null hypothesis probability = 3.164834e-01
Photon flux (15-150 keV) in 86.87 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
S(25-50 keV) vs. S(50-100 keV) plot
S(25-50 keV) = 2.12e-07
S(50-100 keV) = 2.65e-07
T90 vs. Hardness ratio plot
T90 = 77.608000010252 sec.
Hardness ratio (energy fluence ratio) = 1.25
Color vs. Color plot
Count Ratio (25-50 keV) / (15-25 keV) = 1.2446
Count Ratio (50-100 keV) / (15-25 keV) = 0.718292
Mask shadow pattern
IMX = 2.485255591582526E-01, IMY = 8.020716942434582E-02
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:
-239.000000 -28.264000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
244.9937 -15.6426 0.5 32.1 81.1 9.1545 25.2 0.8 Sco X-1
254.4744 35.3596 1.4 35.9 -21.2 1.8316 8.2 1.3 Her X-1
268.3541 -1.3096 5.7 43.8 40.3 1.0191 2.0 8.6 SW J1753.5-0127
216.3023 -9.6719 2.2 22.3 143.2 0.9263 5.2 ------ UNKNOWN
228.0567 31.2963 3.6 21.0 -57.8 0.6729 3.8 ------ UNKNOWN
228.1987 31.6326 4.2 21.3 -57.5 0.6345 3.6 ------ UNKNOWN
188.8443 8.2466 2.5 36.7 -152.9 0.9684 4.7 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image:
-28.264000 58.608000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
245.1033 -15.5935 4.9 32.2 80.9 0.4821 2.3 7.7 Sco X-1
254.5438 35.4844 45.2 36.1 -21.3 -0.0336 -0.3 9.5 Her X-1
268.3891 -1.5911 5.0 43.9 40.7 0.7346 2.3 8.4 SW J1753.5-0127
261.4211 -12.7038 2.1 42.1 59.7 2.2821 5.5 ------ UNKNOWN
258.2489 -13.9317 2.4 40.2 63.9 1.9674 4.8 ------ UNKNOWN
236.9575 20.5593 1.0 14.6 -17.9 1.2366 11.4 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image:
108.500600 963.105000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
244.9843 -15.6331 0.5 37.0 97.8 35.2066 24.8 0.5 Sco X-1
254.4533 35.3453 0.6 21.3 -27.0 9.3073 20.6 0.3 Her X-1
268.3544 -1.3084 12.8 37.7 52.3 1.0735 0.9 8.7 SW J1753.5-0127
288.7891 10.9435 2.2 50.6 23.3 10.1022 5.3 0.6 GRS 1915+105
299.5991 35.2002 0.5 56.3 -8.7 43.4614 21.2 0.4 Cyg X-1
186.4376 17.4114 3.2 47.7 -154.1 3.8092 3.6 ------ UNKNOWN
280.1053 61.6892 4.1 50.7 -44.6 7.7563 2.8 ------ UNKNOWN
Plot creation:
Sun May 31 07:19:37 EDT 2015