Special notes of this burst
Image
Pre-slew 15.0-350.0 keV image (Event data; DETECTION mask)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
91.6694 29.5442 0.0349 40.1001 70.3721 4.1065963 5.450 TRIG_00234516
Foreground time interval of the image:
-169.480 15.864 (delta_t = 185.344 [sec])
Background time interval of the image:
-239.480 -169.480 (delta_t = 70.000 [sec])
Lightcurves
Notes:
- 1) All plots contain as much data as has been downloaded to date.
- 2) The mask-weighted light curves are using the flight position.
- 3) Multiple plots of different time binning/intervals are shown to cover all scenarios of short/long GRBs, rate/image triggers, and real/false positives.
- 4) 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.
- 5) 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.
- 6) 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
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 4.096000
8 ms binning
From T100_start-3 s to T100_start+3 s
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 4.096000
2 ms binning
From T100_start-1 s to T100_start+1 s
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 4.096000
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) 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 -169.224 sec. to 15.192 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.97743 ( -0.334637 0.368532 )
Norm@50keV : 1.38686E-03 ( -0.000334658 0.000321157 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 65.96 using 59 PHA bins.
# Reduced chi-squared = 1.157 for 57 degrees of freedom
# Null hypothesis probability = 1.946693e-01
Photon flux (15-150 keV) in 184.4 sec: 0.205899 ( -0.0385919 0.0386001 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.35584e-06 ( -5.24955e-07 5.42997e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -169.224 sec. to 15.192 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.57671 ( -1.51886 0.578036 )
Epeak [keV] : 44.6048 ( )
Norm@50keV : 2.36452E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 65.64 using 59 PHA bins.
# Reduced chi-squared = 1.172 for 56 degrees of freedom
# Null hypothesis probability = 1.774432e-01
Photon flux (15-150 keV) in 184.4 sec: 0.203404 ( -0.039197 0.038993 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.26937e-06 ( -5.6705e-07 5.96073e-07 ) ergs/cm2
Band function
Time interval is from -169.224 sec. to 15.192 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.62598 ( -3.33397 1.506 )
beta : -9.37005 ( 9.37166 19.3717 )
Epeak [keV] : 45.2855 ( -24.5019 -45.2679 )
Norm@50keV : 2.20986E-03 ( -0.000903473 0.00204588 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 65.64 using 59 PHA bins.
# Reduced chi-squared = 1.193 for 55 degrees of freedom
# Null hypothesis probability = 1.542698e-01
Photon flux (15-150 keV) in 184.4 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 2.28237e-06 ( 0 0 ) ergs/cm2
Single BB
Spectral model blackbody:
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 9.52478 (-2.26069 3.13808)
R^2/D10^2 : 0.114175 (-0.0749317 0.210629)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 73.55 using 59 PHA bins.
# Reduced chi-squared = 1.290 for 57 degrees of freedom
# Null hypothesis probability = 6.917061e-02
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 3.819e-07 1.396e-07
25- 50 8.848e-07 3.128e-07
50-150 4.004e-07 2.079e-07
15-150 1.667e-06 4.972e-07
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 69.6298 (-30.4189 80.4963)
Norm : 1.01743 (-0.286946 0.384734)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 65.75 using 59 PHA bins.
# Reduced chi-squared = 1.153 for 57 degrees of freedom
# Null hypothesis probability = 1.998074e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 4.811e-07 1.220e-07
25- 50 7.643e-07 2.015e-07
50-150 9.778e-07 6.663e-07
15-150 2.223e-06 8.009e-07
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 5.47758 (-1.95995 2.44886)
R1^2/D10^2 : 0.710970 (-0.529168 3.66214)
kT2 [keV] : 20.3609 (-7.4714 21.257)
R2^2/D10^2 : 4.62321E-03 (-0.00423704 0.027116)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 64.41 using 59 PHA bins.
# Reduced chi-squared = 1.171 for 55 degrees of freedom
# Null hypothesis probability = 1.804960e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 5.207e-07 2.970e-07
25- 50 7.090e-07 3.566e-07
50-150 1.073e-06 7.083e-07
15-150 2.303e-06 1.270e-06
Peak spectrum fit
Power-law model
Time interval is from 3.580 sec. to 4.580 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.15755 ( -0.477675 0.597257 )
Norm@50keV : 1.32371E-02 ( -0.00482045 0.00434636 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.32 using 59 PHA bins.
# Reduced chi-squared = 1.006 for 57 degrees of freedom
# Null hypothesis probability = 4.631886e-01
Photon flux (15-150 keV) in 1 sec: 2.14370 ( -0.623837 0.625198 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.23764e-07 ( -3.82588e-08 3.83027e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 3.580 sec. to 4.580 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.93459 ( -1.61238 0.284147 )
Epeak [keV] : 17.3497 ( )
Norm@50keV : 1.68212E-02 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.40 using 59 PHA bins.
# Reduced chi-squared = 1.025 for 56 degrees of freedom
# Null hypothesis probability = 4.231893e-01
Photon flux (15-150 keV) in 1 sec: 2.14525 ( -0.62683 0.62162 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.23634e-07 ( -3.80547e-08 3.8448e-08 ) ergs/cm2
Band function
Time interval is from 3.580 sec. to 4.580 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -2.72506 ( 2.72506 2.72506 )
beta : -2.15755 ( -0.597258 0.477724 )
Epeak [keV] : 34.4895 ( -34.4895 -34.4895 )
Norm@50keV : 1.79911 ( -0.655165 0.590745 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.32 using 59 PHA bins.
# Reduced chi-squared = 1.042 for 55 degrees of freedom
# Null hypothesis probability = 3.891276e-01
Photon flux (15-150 keV) in 1 sec: 2.14344 ( ) 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] : 14.8501 (-14.8902 5.78075)
R^2/D10^2 : 0.210811 (-0.207738 4.03275)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 64.77 using 59 PHA bins.
# Reduced chi-squared = 1.136 for 57 degrees of freedom
# Null hypothesis probability = 2.239805e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 9.749e-09 6.056e-09
25- 50 3.838e-08 2.358e-08
50-150 5.734e-08 3.729e-08
15-150 1.055e-07 6.425e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 71.4506 (-37.8198 120.175)
Norm : 10.2253 (-3.92308 6.36303)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.11 using 59 PHA bins.
# Reduced chi-squared = 1.019 for 57 degrees of freedom
# Null hypothesis probability = 4.343374e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.629e-08 1.100e-08
25- 50 4.206e-08 1.784e-08
50-150 5.484e-08 4.182e-08
15-150 1.232e-07 6.155e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 3.71344 (-2.97196 2.70516)
R1^2/D10^2 : 47.0145 (-43.4682 -47.0098)
kT2 [keV] : 19.4042 (-5.8584 11.0639)
R2^2/D10^2 : 6.34346E-02 (-0.0535312 0.203642)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 55.39 using 59 PHA bins.
# Reduced chi-squared = 1.007 for 55 degrees of freedom
# Null hypothesis probability = 4.599334e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 3.414e-08 2.005e-08
25- 50 3.130e-08 1.698e-08
50-150 6.323e-08 3.973e-08
15-150 1.287e-07 6.895e-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: 1.97743 ( -0.334637 0.368532 )
Norm@50keV : 1.38686E-03 ( -0.000334658 0.000321157 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 65.96 using 59 PHA bins.
# Reduced chi-squared = 1.157 for 57 degrees of freedom
# Null hypothesis probability = 1.946693e-01
Photon flux (15-150 keV) in 184.4 sec: 0.205899 ( -0.0385919 0.0386001 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.35584e-06 ( -5.24955e-07 5.42997e-07 ) ergs/cm2
Cutoff power-law model
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.57671 ( -1.51886 0.578131 )
Epeak [keV] : 44.6048 ( )
Norm@50keV : 2.36452E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 65.64 using 59 PHA bins.
# Reduced chi-squared = 1.172 for 56 degrees of freedom
# Null hypothesis probability = 1.774432e-01
Photon flux (15-150 keV) in 184.4 sec: 0.203404 ( -0.039197 0.038993 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.26937e-06 ( -5.6705e-07 5.96073e-07 ) ergs/cm2
Band function
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.62598 ( -3.33397 1.506 )
beta : -9.37005 ( 9.37166 19.3717 )
Epeak [keV] : 45.2855 ( -24.5019 -45.2679 )
Norm@50keV : 2.20986E-03 ( -0.000903473 0.00210412 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 65.64 using 59 PHA bins.
# Reduced chi-squared = 1.193 for 55 degrees of freedom
# Null hypothesis probability = 1.542698e-01
Photon flux (15-150 keV) in 184.4 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 2.28237e-06 ( 0 0 ) ergs/cm2
S(25-50 keV) vs. S(50-100 keV) plot
S(25-50 keV) = 7.04e-07
S(50-100 keV) = 7.16e-07
T90 vs. Hardness ratio plot
T90 = 180.383999973536 sec.
Hardness ratio (energy fluence ratio) = 1.01705
Color vs. Color plot
Count Ratio (25-50 keV) / (15-25 keV) = 0.823377
Count Ratio (50-100 keV) / (15-25 keV) = 0.612795
Mask shadow pattern (with DETECTION mask)
IMX = 2.828634467430531E-01, IMY = -7.931505063363159E-01
TIME vs. PHA plot around the trigger time
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 4.096000
TIME vs. DetID plot around the trigger time
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 4.096000
100 us light curve (15-350 keV)
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 4.096000
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:
-239.480000 -169.224000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
198.9603 69.2268 3.1 40.7 -169.6 0.4185 3.7 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image:
-169.224000 15.192000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
161.6889 77.4084 2.4 36.7 170.4 1.6098 4.8 ------ UNKNOWN
211.6453 60.2853 2.3 46.2 -156.7 2.1240 5.0 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image:
268.220600 962.600000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
244.9833 -15.6443 0.5 39.8 -58.4 21.0980 23.8 0.3 Sco X-1
255.9957 -37.8275 0.6 21.7 -91.5 8.2787 18.6 1.1 4U 1700-377
256.4188 -36.4162 2.5 21.6 -87.6 2.0016 4.6 0.9 GX 349+2
263.0282 -24.7555 1.4 20.9 -51.3 3.3462 8.2 1.2 GX 1+4
264.7316 -44.5949 13.5 16.2 -115.4 0.3363 0.9 8.7 4U 1735-44
268.3656 -1.4139 3.6 37.7 -14.6 1.5572 3.2 2.3 SW J1753.5-0127
270.2597 -25.1041 2.0 15.9 -37.8 2.2713 5.8 2.0 GX 5-1
270.3194 -25.7445 3.4 15.4 -39.2 1.3985 3.6 0.9 GRS 1758-258
273.9056 -14.0769 2.2 23.9 -12.7 2.3002 5.2 6.3 GX 17+2
275.8394 -30.3338 2.7 8.7 -37.2 1.6145 4.3 4.9 H1820-303
284.9763 -24.9566 4.5 11.6 17.9 0.8764 2.5 3.9 HT1900.1-2455
288.7977 10.9436 1.1 47.7 17.6 9.4618 10.2 0.1 GRS 1915+105
263.0085 -33.8937 3.9 16.8 -76.8 1.1410 2.9 3.7 GX 354-0
277.3501 -23.7841 2.4 13.7 -13.3 1.7654 4.7 ------ UNKNOWN
258.2543 -56.3114 2.8 26.0 -137.3 1.5038 4.2 ------ UNKNOWN
243.6111 -55.5795 3.5 32.8 -127.9 1.7573 3.3 ------ UNKNOWN
199.9838 -68.7698 3.4 54.0 -143.3 7.9195 3.4 ------ UNKNOWN
225.5920 -47.5739 2.9 43.2 -113.3 6.2595 3.9 ------ UNKNOWN
241.7320 -8.0072 3.0 47.3 -53.1 6.2065 3.9 ------ UNKNOWN
Plot creation:
Fri Dec 18 20:53:17 EST 2015