Special notes of this burst
Image
Pre-slew 15.0-350.0 keV image (Event data)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
126.0645 -45.5334 0.0093 27.3376 -18.7203 0.9865420 20.691 TRIG_00160672
Foreground time interval of the image:
-4.640 14.429 (delta_t = 19.069 [sec])
Background time interval of the image:
-299.472 -4.640 (delta_t = 294.832 [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
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 1.024000
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 1.024000
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 1.024000
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 -4.640 sec. to 54.688 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.54427 ( -0.136933 0.138839 )
Norm@50keV : 1.59861E-03 ( -0.000135145 0.00013429 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 65.55 using 59 PHA bins.
# Reduced chi-squared = 1.150 for 57 degrees of freedom
# Null hypothesis probability = 2.043782e-01
Photon flux (15-150 keV) in 59.33 sec: 0.202041 ( -0.0163457 0.0163589 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.93617e-07 ( -8.21762e-08 8.31018e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -4.640 sec. to 54.688 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.482353 ( -0.727364 0.627235 )
Epeak [keV] : 68.6830 ( -11.7264 31.8206 )
Norm@50keV : 5.65973E-03 ( -0.00292854 0.00745013 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.44 using 59 PHA bins.
# Reduced chi-squared = 1.008 for 56 degrees of freedom
# Null hypothesis probability = 4.585278e-01
Photon flux (15-150 keV) in 59.33 sec: 0.192492 ( -0.01725 0.017239 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.19424e-07 ( -8.86568e-08 9.18962e-08 ) ergs/cm2
Band function
Time interval is from -4.640 sec. to 54.688 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.482277 ( -0.527892 0.647923 )
beta : -10.00000 ( 10 20 )
Epeak [keV] : 68.6688 ( -10.1962 31.8202 )
Norm@50keV : 5.66048E-03 ( -0.0029301 0.00747457 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.44 using 59 PHA bins.
# Reduced chi-squared = 1.026 for 55 degrees of freedom
# Null hypothesis probability = 4.210157e-01
Photon flux (15-150 keV) in 59.33 sec: 0.192489 ( ) 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] : 14.4113 (-1.26589 1.39932)
R^2/D10^2 : 2.67462E-02 (-0.00750612 0.0103274)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 71.46 using 59 PHA bins.
# Reduced chi-squared = 1.254 for 57 degrees of freedom
# Null hypothesis probability = 9.417439e-02
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 6.940e-08 1.023e-08
25- 50 2.655e-07 2.978e-08
50-150 3.684e-07 6.247e-08
15-150 7.033e-07 7.327e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 179.131 (-58.8038 -181.331)
Norm : 0.828841 (-0.0693593 0.0742044)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 60.81 using 59 PHA bins.
# Reduced chi-squared = 1.067 for 57 degrees of freedom
# Null hypothesis probability = 3.403406e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.241e-07 4.401e-08
25- 50 2.356e-07 1.086e-07
50-150 4.980e-07 2.691e-07
15-150 8.577e-07 4.536e-07
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 5.01459 (-1.66561 2.22618)
R1^2/D10^2 : 0.488726 (-0.356817 2.32697)
kT2 [keV] : 17.8063 (-2.349 3.57994)
R2^2/D10^2 : 1.10965E-02 (-0.00586235 0.00742702)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.00 using 59 PHA bins.
# Reduced chi-squared = 0.9819 for 55 degrees of freedom
# Null hypothesis probability = 5.127248e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.133e-07 5.208e-08
25- 50 2.393e-07 7.063e-08
50-150 4.434e-07 1.315e-07
15-150 7.960e-07 2.038e-07
Peak spectrum fit
Power-law model
Time interval is from -0.668 sec. to 0.332 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.37775 ( -0.319025 0.32154 )
Norm@50keV : 6.21292E-03 ( -0.00112154 0.00111115 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 68.03 using 59 PHA bins.
# Reduced chi-squared = 1.193 for 57 degrees of freedom
# Null hypothesis probability = 1.504498e-01
Photon flux (15-150 keV) in 1 sec: 0.752884 ( -0.134003 0.13422 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.03131e-08 ( -1.22026e-08 1.24182e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.668 sec. to 0.332 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.38734 ( -0.8341 0.316006 )
Epeak [keV] : 9999.36 ( -9999.36 -9999.36 )
Norm@50keV : 6.19495E-03 ( -0.00111644 0.0249559 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 68.04 using 59 PHA bins.
# Reduced chi-squared = 1.215 for 56 degrees of freedom
# Null hypothesis probability = 1.298937e-01
Photon flux (15-150 keV) in 1 sec: 0.753644 ( -0.135142 0.133236 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.01473e-08 ( -1.28464e-08 1.24441e-08 ) ergs/cm2
Band function
Time interval is from -0.668 sec. to 0.332 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.11418 ( 1.11545 5.35453 )
beta : -1.48320 ( 1.47498 0.416464 )
Epeak [keV] : 150.180 ( -165.987 -165.987 )
Norm@50keV : 8.58609E-03 ( -0.00309819 0 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 68.04 using 59 PHA bins.
# Reduced chi-squared = 1.237 for 55 degrees of freedom
# Null hypothesis probability = 1.114530e-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] : 15.1931 (-2.88619 3.93536)
R^2/D10^2 : 8.37136E-02 (-0.046086 0.0899309)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 74.48 using 59 PHA bins.
# Reduced chi-squared = 1.307 for 57 degrees of freedom
# Null hypothesis probability = 5.992593e-02
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 4.037e-09 1.335e-09
25- 50 1.623e-08 5.143e-09
50-150 2.564e-08 9.670e-09
15-150 4.590e-08 1.259e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 199.363 (-85.0243 -199.363)
Norm : 3.08844 (-0.54544 0.545435)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 69.16 using 59 PHA bins.
# Reduced chi-squared = 1.213 for 57 degrees of freedom
# Null hypothesis probability = 1.295597e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 7.691e-09 4.474e-09
25- 50 1.479e-08 8.525e-09
50-150 3.244e-08 1.831e-08
15-150 5.493e-08 3.173e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 2.24426 (-1.14382 2.77782)
R1^2/D10^2 : 148.628 (-153.334 133562)
kT2 [keV] : 17.2966 (-3.67084 5.96814)
R2^2/D10^2 : 5.07020E-02 (-0.032576 0.057556)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 68.18 using 59 PHA bins.
# Reduced chi-squared = 1.240 for 55 degrees of freedom
# Null hypothesis probability = 1.092067e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 6.660e-09 2.960e-09
25- 50 1.396e-08 6.226e-09
50-150 2.961e-08 1.257e-08
15-150 5.023e-08 2.071e-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: 1.27714 ( -0.127549 0.126414 )
Norm@50keV : 3.40351E-03 ( -0.000249488 0.000249356 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 53.06 using 59 PHA bins.
# Reduced chi-squared = 0.9309 for 57 degrees of freedom
# Null hypothesis probability = 6.235303e-01
Photon flux (15-150 keV) in 19.07 sec: 0.404385 ( -0.0303744 0.0304198 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.45029e-07 ( -5.25855e-08 5.29286e-08 ) ergs/cm2
Cutoff power-law model
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.864713 ( -0.57281 0.466124 )
Epeak [keV] : 141.792 ( -54.8509 -141.8 )
Norm@50keV : 5.44031E-03 ( -0.00215479 0.00476646 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 51.14 using 59 PHA bins.
# Reduced chi-squared = 0.9133 for 56 degrees of freedom
# Null hypothesis probability = 6.589128e-01
Photon flux (15-150 keV) in 19.07 sec: 0.397232 ( -0.031797 0.031671 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.25122e-07 ( -5.90197e-08 5.86479e-08 ) ergs/cm2
Band function
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 4.96879 ( -0.083685 -4.96879 )
beta : -1.38944 ( -0.153648 0.148982 )
Epeak [keV] : 27.2833 ( -5.24916 4.22858 )
Norm@50keV : 170.884 ( -12.4324 479.13 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 47.87 using 59 PHA bins.
# Reduced chi-squared = 0.8704 for 55 degrees of freedom
# Null hypothesis probability = 7.412524e-01
Photon flux (15-150 keV) in 19.07 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) = 2.26e-07
S(50-100 keV) = 3.10e-07
T90 vs. Hardness ratio plot
T90 = 46.5119999647141 sec.
Hardness ratio (energy fluence ratio) = 1.37168
Color vs. Color plot
Count Ratio (25-50 keV) / (15-25 keV) = 1.42273
Count Ratio (50-100 keV) / (15-25 keV) = 1.13245
Mask shadow pattern
IMX = 4.896213709906972E-01, IMY = 1.659209379960770E-01
TIME vs. PHA plot around the trigger time
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 1.024000
TIME vs. DetID plot around the trigger time
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 1.024000
100 us light curve (15-350 keV)
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 1.024000
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:
-299.472000 -4.640000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
135.5655 -40.5436 4.9 24.8 -37.4 0.4747 2.4 1.8 Vela X-1
108.4566 -75.3176 2.6 57.5 -9.5 4.6938 4.4 ------ UNKNOWN
146.2396 10.1688 3.1 36.7 -152.9 0.9414 3.8 ------ UNKNOWN
131.7479 -74.5552 3.5 56.4 -16.6 2.6311 3.3 ------ UNKNOWN
137.4659 -72.2597 3.7 54.6 -19.2 2.0894 3.1 ------ UNKNOWN
148.9214 -31.8150 2.6 27.1 -68.9 1.0282 4.4 ------ UNKNOWN
152.7146 17.8181 3.8 46.6 -153.0 1.2187 3.0 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image:
-4.640000 14.428600
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
135.6077 -40.6528 6.6 24.9 -37.3 -0.0806 -1.8 6.9 Vela X-1
139.6703 24.8137 2.2 46.2 -172.4 0.4223 5.3 ------ UNKNOWN
126.0645 -45.5334 0.6 27.3 -18.7 0.9865 20.7 ------ UNKNOWN
138.9544 -51.0982 2.7 35.2 -31.4 0.2352 4.4 ------ UNKNOWN
129.0326 -75.3728 2.2 57.1 -15.6 1.1499 5.2 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image:
64.428610 302.541000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
135.3137 -40.4195 0.0 8.5 -124.8 -0.0756 -0.5 12.7 Vela X-1
169.9424 -60.5907 0.0 29.6 -44.7 -0.1672 -0.8 11.2 Cen X-3
186.5604 -62.8530 8.4 37.6 -41.8 0.3526 1.4 5.6 GX 301-2
115.5094 5.7750 2.7 52.2 165.6 2.6459 4.3 ------ UNKNOWN
196.5880 -78.8444 2.3 41.8 -17.0 1.2467 5.1 ------ UNKNOWN
Plot creation:
Sun May 31 15:18:41 EDT 2015