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Image
Pre-slew 15.0-350.0 keV image (Event data)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
89.4162 80.9572 0.0071 25.3158 -132.0587 3.6557287 27.093 TRIG_00458521
Foreground time interval of the image:
-24.088 38.493 (delta_t = 62.581 [sec])
Background time interval of the image:
-239.208 -24.088 (delta_t = 215.120 [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 -24.088 sec. to 384.988 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.82410 ( -0.0989145 0.100644 )
Norm@50keV : 1.21174E-03 ( -6.93572e-05 6.86786e-05 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 76.81 using 59 PHA bins.
# Reduced chi-squared = 1.347 for 57 degrees of freedom
# Null hypothesis probability = 4.126035e-02
Photon flux (15-150 keV) in 409.1 sec: 0.168561 ( -0.00854817 0.00856011 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.56036e-06 ( -2.64026e-07 2.66783e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -24.088 sec. to 384.988 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.61094 ( -0.39488 0.290032 )
Epeak [keV] : 83.4516 ( -29.4864 -83.4516 )
Norm@50keV : 1.57494E-03 ( -0.000417384 0.000957598 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 75.82 using 59 PHA bins.
# Reduced chi-squared = 1.354 for 56 degrees of freedom
# Null hypothesis probability = 4.005293e-02
Photon flux (15-150 keV) in 409.1 sec: 0.166178 ( -0.00941 0.009409 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.45367e-06 ( -3.19057e-07 3.19548e-07 ) ergs/cm2
Band function
Time interval is from -24.088 sec. to 384.988 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.61096 ( 1.19245 1.19245 )
beta : -9.33694 ( 9.35615 19.3561 )
Epeak [keV] : 83.4387 ( -27.8167 124.046 )
Norm@50keV : 1.57458E-03 ( -0.000409065 0.000721073 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 75.82 using 59 PHA bins.
# Reduced chi-squared = 1.379 for 55 degrees of freedom
# Null hypothesis probability = 3.284833e-02
Photon flux (15-150 keV) in 409.1 sec: 0.166293 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 4.43828e-06 ( 0 0 ) ergs/cm2
Single BB
Spectral model blackbody:
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 11.9011 ( )
R^2/D10^2 : 3.92808E-02 ( )
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 170.83 using 59 PHA bins.
# Reduced chi-squared = 2.9970 for 57 degrees of freedom
# Null hypothesis probability = 2.682571e-13
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 4.811e-07 4.193e-08
25- 50 1.499e-06 8.796e-08
50-150 1.270e-06 1.638e-07
15-150 3.250e-06 2.095e-07
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 98.7745 (-18.3628 26.0418)
Norm : 0.734781 (-0.0539187 0.0609906)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 77.66 using 59 PHA bins.
# Reduced chi-squared = 1.362 for 57 degrees of freedom
# Null hypothesis probability = 3.582433e-02
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 7.856e-07 7.200e-08
25- 50 1.355e-06 8.182e-08
50-150 2.181e-06 6.153e-07
15-150 4.321e-06 6.662e-07
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 5.42163 (-0.751439 0.842428)
R1^2/D10^2 : 0.511953 (-0.217982 0.429802)
kT2 [keV] : 20.1370 (-2.50729 3.39124)
R2^2/D10^2 : 4.54602E-03 (-0.00202725 0.00305704)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 72.26 using 59 PHA bins.
# Reduced chi-squared = 1.314 for 55 degrees of freedom
# Null hypothesis probability = 5.916492e-02
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 8.416e-07 1.608e-07
25- 50 1.278e-06 1.847e-07
50-150 2.216e-06 4.735e-07
15-150 4.335e-06 7.822e-07
Peak spectrum fit
Power-law model
Time interval is from 341.784 sec. to 342.784 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.85918 ( -0.278597 0.300983 )
Norm@50keV : 7.15213E-03 ( -0.00141261 0.00136215 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 60.49 using 59 PHA bins.
# Reduced chi-squared = 1.061 for 57 degrees of freedom
# Null hypothesis probability = 3.511722e-01
Photon flux (15-150 keV) in 1 sec: 1.00908 ( -0.153361 0.153363 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.57558e-08 ( -1.25851e-08 1.30532e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 341.784 sec. to 342.784 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.64629 ( -1.11655 0.612976 )
Epeak [keV] : 70.4826 ( -70.457 -70.4819 )
Norm@50keV : 9.49044E-03 ( -0.00949053 0.0328984 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 60.33 using 59 PHA bins.
# Reduced chi-squared = 1.077 for 56 degrees of freedom
# Null hypothesis probability = 3.221352e-01
Photon flux (15-150 keV) in 1 sec: 1.00135 ( -0.156389 0.15646 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.42129e-08 ( -1.40545e-08 1.41855e-08 ) ergs/cm2
Band function
Time interval is from 341.784 sec. to 342.784 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.64672 ( -1.68029 0.978241 )
beta : -10.0000 ( 10 0 )
Epeak [keV] : 70.5328 ( -63.8809 -70.5328 )
Norm@50keV : 9.48299E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 60.33 using 59 PHA bins.
# Reduced chi-squared = 1.097 for 55 degrees of freedom
# Null hypothesis probability = 2.891761e-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] : 9.42921 (-1.74048 2.41442)
R^2/D10^2 : 0.578523 (-0.330444 0.677257)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 72.48 using 59 PHA bins.
# Reduced chi-squared = 1.271 for 57 degrees of freedom
# Null hypothesis probability = 8.121698e-02
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.024e-08 2.905e-09
25- 50 2.337e-08 5.125e-09
50-150 1.026e-08 4.630e-09
15-150 4.387e-08 1.093e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 85.8209 (-36.0763 95.8191)
Norm : 4.64277 (-0.931436 1.24409)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 60.66 using 59 PHA bins.
# Reduced chi-squared = 1.064 for 57 degrees of freedom
# Null hypothesis probability = 3.454322e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.209e-08 2.677e-09
25- 50 2.024e-08 4.060e-09
50-150 2.991e-08 1.840e-08
15-150 6.224e-08 2.245e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 6.15377 (-1.65551 1.85819)
R1^2/D10^2 : 2.20725 (-1.37252 5.3535)
kT2 [keV] : 25.0648 (-8.40063 20.0971)
R2^2/D10^2 : 1.15119E-02 (-0.010357 0.0454041)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.67 using 59 PHA bins.
# Reduced chi-squared = 1.067 for 55 degrees of freedom
# Null hypothesis probability = 3.425400e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.276e-08 7.045e-09
25- 50 1.925e-08 1.024e-08
50-150 3.442e-08 2.142e-08
15-150 6.643e-08 3.579e-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: 1.66014 ( -0.0985289 0.0995812 )
Norm@50keV : 3.71380E-03 ( -0.000203342 0.00020197 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 65.14 using 59 PHA bins.
# Reduced chi-squared = 1.143 for 57 degrees of freedom
# Null hypothesis probability = 2.146746e-01
Photon flux (15-150 keV) in 62.58 sec: 0.486564 ( -0.0253898 0.0254453 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.15934e-06 ( -1.263e-07 1.27383e-07 ) ergs/cm2
Cutoff power-law model
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.63722 ( -0.381836 0.121029 )
Epeak [keV] : 758.852 ( )
Norm@50keV : 3.81704E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 65.12 using 59 PHA bins.
# Reduced chi-squared = 1.163 for 56 degrees of freedom
# Null hypothesis probability = 1.889934e-01
Photon flux (15-150 keV) in 62.58 sec: 0.485006 ( -0.026918 0.026745 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.14911e-06 ( -1.44816e-07 1.36781e-07 ) ergs/cm2
Band function
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.769974 ( 1.08751 1.08751 )
beta : -1.68009 ( 1.67708 0.110531 )
Epeak [keV] : 34.2509 ( -33.8239 -33.8239 )
Norm@50keV : 1.71696E-02 ( -0.017785 619.393 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 64.82 using 59 PHA bins.
# Reduced chi-squared = 1.179 for 55 degrees of freedom
# Null hypothesis probability = 1.714644e-01
Photon flux (15-150 keV) in 62.58 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) = 1.30e-06
S(50-100 keV) = 1.46e-06
T90 vs. Hardness ratio plot
T90 = 385.255999922752 sec.
Hardness ratio (energy fluence ratio) = 1.12308
Color vs. Color plot
Count Ratio (25-50 keV) / (15-25 keV) = 1.07457
Count Ratio (50-100 keV) / (15-25 keV) = 0.699003
Mask shadow pattern
IMX = -3.168826698086088E-01, IMY = 3.512100248643446E-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:
-239.208000 -24.088000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
43.0404 8.0492 2.5 55.1 8.9 4.9786 4.7 ------ UNKNOWN
70.6707 35.3960 2.7 38.0 -38.0 1.2884 4.3 ------ UNKNOWN
99.4821 54.0427 3.3 37.4 -83.5 2.2137 3.5 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image:
-24.088000 38.492610
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
89.4163 80.9572 0.4 25.3 -132.1 3.6557 27.1 ------ UNKNOWN
69.0541 28.1746 1.9 43.6 -30.7 1.3100 6.1 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image:
87.692600 962.907100
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
245.6891 54.5465 2.7 43.8 154.6 5.3048 4.3 ------ UNKNOWN
38.0833 47.4644 2.6 37.4 15.1 3.5133 4.5 ------ UNKNOWN
89.3239 80.9721 1.3 0.0 -97.0 4.7346 8.8 ------ UNKNOWN
130.9985 53.2003 2.5 30.6 -96.6 3.6674 4.7 ------ UNKNOWN
147.8787 52.9130 2.9 33.2 -115.2 3.6186 4.0 ------ UNKNOWN
69.9515 22.6755 3.4 58.9 -24.1 13.5399 3.5 ------ UNKNOWN
183.2005 35.8842 3.3 55.3 -145.3 16.9525 3.6 ------ UNKNOWN
182.8224 35.8110 6.4 55.3 -144.9 9.3154 2.2 ------ UNKNOWN
170.2602 39.9928 2.8 49.2 -133.6 10.9398 4.1 ------ UNKNOWN
91.9591 31.9307 3.3 49.1 -48.0 10.2028 3.5 ------ UNKNOWN
Plot creation:
Sat May 30 21:53:17 EDT 2015