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
169.6858 -15.5447 0.0226 46.3730 -171.4621 1.0907411 8.436 TRIG_00145994
Foreground time interval of the image:
13.492 68.248 (delta_t = 54.756 [sec])
Background time interval of the image:
-159.299 -83.000 (delta_t = 76.300 [sec])
-82.000 13.492 (delta_t = 95.492 [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 64.000000
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 64.000000
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 64.000000
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 13.492 sec. to 68.248 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.39618 ( -0.261876 0.290435 )
Norm@50keV : 1.18008E-03 ( -0.000253678 0.000251516 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.86 using 59 PHA bins.
# Reduced chi-squared = 1.050 for 57 degrees of freedom
# Null hypothesis probability = 3.722271e-01
Photon flux (15-150 keV) in 54.76 sec: 0.217856 ( -0.0311277 0.0311277 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.29756e-07 ( -1.07095e-07 1.11098e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from 13.492 sec. to 68.248 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.72899E-02 ( -2.01284 1.48911 )
Epeak [keV] : 30.1552 ( -6.10122 6.13116 )
Norm@50keV : 3.91151E-02 ( -0.0402669 0.76658 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 50.75 using 59 PHA bins.
# Reduced chi-squared = 0.9063 for 56 degrees of freedom
# Null hypothesis probability = 6.732335e-01
Photon flux (15-150 keV) in 54.76 sec: 0.208863 ( -0.030757 0.030934 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.50272e-07 ( -9.18123e-08 1.02494e-07 ) ergs/cm2
Band function
Time interval is from 13.492 sec. to 68.248 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -5.82674E-02 ( -1.38805 2.12286 )
beta : -9.37167 ( 9.37167 19.3705 )
Epeak [keV] : 30.2831 ( -5.47734 6.04733 )
Norm@50keV : 3.39434E-02 ( -0.0339729 6.9897 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 50.77 using 59 PHA bins.
# Reduced chi-squared = 0.9231 for 55 degrees of freedom
# Null hypothesis probability = 6.369030e-01
Photon flux (15-150 keV) in 54.76 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] : 8.12895 (-1.11525 1.25491)
R^2/D10^2 : 0.235353 (-0.104144 0.19336)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 52.62 using 59 PHA bins.
# Reduced chi-squared = 0.9231 for 57 degrees of freedom
# Null hypothesis probability = 6.400416e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.558e-07 3.863e-08
25- 50 2.803e-07 5.399e-08
50-150 7.756e-08 3.188e-08
15-150 5.137e-07 9.709e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 35.5534 (-9.45311 14.2251)
Norm : 1.56697 (-0.369703 0.503835)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 53.03 using 59 PHA bins.
# Reduced chi-squared = 0.9303 for 57 degrees of freedom
# Null hypothesis probability = 6.248813e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.887e-07 3.376e-08
25- 50 2.353e-07 4.712e-08
50-150 1.592e-07 7.319e-08
15-150 5.831e-07 1.246e-07
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 4.38649 (-4.37823 41.5297)
R1^2/D10^2 : 1.14003 (-1.14372 -1.14372)
kT2 [keV] : 10.0037 (-10.0001 -10.0001)
R2^2/D10^2 : 7.89141E-02 (-0.0791024 0.223345)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 50.39 using 59 PHA bins.
# Reduced chi-squared = 0.9162 for 55 degrees of freedom
# Null hypothesis probability = 6.511402e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.753e-07 9.397e-08
25- 50 2.598e-07 1.397e-07
50-150 1.153e-07 7.335e-08
15-150 5.504e-07 2.806e-07
Peak spectrum fit
Power-law model
Time interval is from 55.168 sec. to 56.168 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.01151 ( -0.720297 0.904169 )
Norm@50keV : 3.66710E-03 ( -0.0036671 0.00178842 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.33 using 59 PHA bins.
# Reduced chi-squared = 1.006 for 57 degrees of freedom
# Null hypothesis probability = 4.629935e-01
Photon flux (15-150 keV) in 1 sec: 0.552998 ( -0.219589 0.219697 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.38389e-08 ( -1.55874e-08 1.6667e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 55.168 sec. to 56.168 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.87009 ( -1.885 0.217032 )
Epeak [keV] : 38.8236 ( )
Norm@50keV : 4.42248E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.31 using 59 PHA bins.
# Reduced chi-squared = 1.023 for 56 degrees of freedom
# Null hypothesis probability = 4.261630e-01
Photon flux (15-150 keV) in 1 sec: 0.551054 ( -0.219184 0.22096 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.3456e-08 ( -3.3456e-08 1.69822e-08 ) ergs/cm2
Band function
Time interval is from 55.168 sec. to 56.168 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 3.96348 ( -5.8265 -3.98557 )
beta : -2.12951 ( 2.3997 1.07509 )
Epeak [keV] : 21.2211 ( -21.0239 115.065 )
Norm@50keV : 258.607 ( -286.166 640.663 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.05 using 59 PHA bins.
# Reduced chi-squared = 1.037 for 55 degrees of freedom
# Null hypothesis probability = 3.989399e-01
Photon flux (15-150 keV) in 1 sec: 0.550343 ( ) 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] : 7.34888 (-2.59362 7.08793)
R^2/D10^2 : 0.841480 (-0.841401 4.24994)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.00 using 59 PHA bins.
# Reduced chi-squared = 1.035 for 57 degrees of freedom
# Null hypothesis probability = 4.022108e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 7.657e-09 4.932e-09
25- 50 1.150e-08 7.825e-09
50-150 2.266e-09 2.165e-09
15-150 2.143e-08 1.387e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 68.0144 (-68.0095 -68.0095)
Norm : 2.74664 (-1.34513 3.85129)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.47 using 59 PHA bins.
# Reduced chi-squared = 1.008 for 57 degrees of freedom
# Null hypothesis probability = 4.576355e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 7.024e-09 4.535e-09
25- 50 1.109e-08 7.065e-09
50-150 1.394e-08 1.279e-08
15-150 3.205e-08 2.279e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 5.86029 (-2.05392 3.71053)
R1^2/D10^2 : 1.72141 (-0.862292 20.6607)
kT2 [keV] : 27.1497 (-27.7649 -27.7652)
R2^2/D10^2 : 4.20512E-03 (-0.00402863 0.0167474)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.04 using 59 PHA bins.
# Reduced chi-squared = 1.019 for 55 degrees of freedom
# Null hypothesis probability = 4.358078e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 8.102e-09 5.340e-09
25- 50 1.022e-08 5.985e-09
50-150 1.693e-08 1.018e-08
15-150 3.526e-08 1.926e-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: 2.39618 ( -0.261876 0.290435 )
Norm@50keV : 1.18008E-03 ( -0.000253678 0.000251516 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.86 using 59 PHA bins.
# Reduced chi-squared = 1.050 for 57 degrees of freedom
# Null hypothesis probability = 3.722271e-01
Photon flux (15-150 keV) in 54.76 sec: 0.217856 ( -0.0311277 0.0311277 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.29756e-07 ( -1.07095e-07 1.11098e-07 ) ergs/cm2
Cutoff power-law model
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.72899E-02 ( -2.01284 1.48911 )
Epeak [keV] : 30.1552 ( -6.10122 6.13116 )
Norm@50keV : 3.91151E-02 ( -0.0402669 0.76658 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 50.75 using 59 PHA bins.
# Reduced chi-squared = 0.9063 for 56 degrees of freedom
# Null hypothesis probability = 6.732335e-01
Photon flux (15-150 keV) in 54.76 sec: 0.208863 ( -0.030757 0.030934 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.50272e-07 ( -9.18123e-08 1.02494e-07 ) ergs/cm2
Band function
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -5.82674E-02 ( -1.38805 2.12286 )
beta : -9.37167 ( 9.37167 19.3705 )
Epeak [keV] : 30.2831 ( -5.47734 6.04733 )
Norm@50keV : 3.39434E-02 ( -0.0339729 6.9897 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 50.77 using 59 PHA bins.
# Reduced chi-squared = 0.9231 for 55 degrees of freedom
# Null hypothesis probability = 6.369030e-01
Photon flux (15-150 keV) in 54.76 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) = 2.06e-07
S(50-100 keV) = 1.57e-07
T90 vs. Hardness ratio plot
T90 = 49.363999992609 sec.
Hardness ratio (energy fluence ratio) = 0.762136
Color vs. Color plot
Count Ratio (25-50 keV) / (15-25 keV) = 1.06415
Count Ratio (50-100 keV) / (15-25 keV) = 0.210363
Mask shadow pattern
IMX = -1.037486857582655E+00, IMY = 1.557545036574831E-01
TIME vs. PHA plot around the trigger time
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 64.000000
TIME vs. DetID plot around the trigger time
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 64.000000
100 us light curve (15-350 keV)
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 64.000000
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:
-159.299400 -82.999600
-82.000000 13.492000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image:
13.492000 68.248000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
216.8186 42.4002 2.8 29.0 39.9 0.3602 4.1 ------ UNKNOWN
169.6857 -15.5447 1.4 46.4 -171.5 1.0906 8.4 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image:
137.700600 303.047800
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
135.3561 -40.5859 66.9 38.9 -169.9 0.0288 0.2 8.1 Vela X-1
170.2992 -60.7195 5.0 45.2 146.7 0.8953 2.3 5.8 Cen X-3
182.7583 -60.8693 2.9 46.3 138.4 2.0378 4.0 ------ UNKNOWN
202.1198 32.1615 2.2 56.9 -0.1 4.0612 5.2 ------ UNKNOWN
184.2853 35.6777 2.4 53.0 -18.1 1.7173 4.8 ------ UNKNOWN
Plot creation:
Sun May 31 16:34:50 EDT 2015