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
136.6322 35.1514 0.0118 14.6022 99.2895 1.1813287 16.225 TRIG_00305011
Foreground time interval of the image:
-0.440 49.861 (delta_t = 50.301 [sec])
Background time interval of the image:
-239.440 -0.440 (delta_t = 239.000 [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 8.192000
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 8.192000
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 8.192000
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 -0.440 sec. to 140.560 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.69897 ( -0.193282 0.198745 )
Norm@50keV : 7.10105E-04 ( -8.57503e-05 8.39157e-05 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 49.33 using 59 PHA bins.
# Reduced chi-squared = 0.8654 for 57 degrees of freedom
# Null hypothesis probability = 7.550703e-01
Photon flux (15-150 keV) in 141 sec: 9.42759E-02 ( -0.00985653 0.00985963 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.27113e-07 ( -1.17082e-07 1.19308e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.440 sec. to 140.560 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.69541 ( -0.525719 0.202006 )
Epeak [keV] : 9999.19 ( -9999.35 -9999.36 )
Norm@50keV : 7.12365E-04 ( -8.67155e-05 0.000671489 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 49.33 using 59 PHA bins.
# Reduced chi-squared = 0.8809 for 56 degrees of freedom
# Null hypothesis probability = 7.235286e-01
Photon flux (15-150 keV) in 141 sec: 9.42960E-02 ( -0.0099031 0.009817 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.25647e-07 ( -1.19182e-07 1.17745e-07 ) ergs/cm2
Band function
Time interval is from -0.440 sec. to 140.560 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 4.65768 ( -4.65768 -4.65768 )
beta : -1.76797 ( -0.236184 0.216793 )
Epeak [keV] : 21.5670 ( -21.567 5.59653 )
Norm@50keV : 122.518 ( -12.7438 552927 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 48.88 using 59 PHA bins.
# Reduced chi-squared = 0.8888 for 55 degrees of freedom
# Null hypothesis probability = 7.060756e-01
Photon flux (15-150 keV) in 141 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] : 11.0819 (-1.48683 1.78876)
R^2/D10^2 : 2.97339E-02 (-0.0125607 0.0209624)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 77.59 using 59 PHA bins.
# Reduced chi-squared = 1.361 for 57 degrees of freedom
# Null hypothesis probability = 3.619873e-02
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.077e-07 1.965e-08
25- 50 3.075e-07 4.082e-08
50-150 2.146e-07 5.732e-08
15-150 6.298e-07 1.000e-07
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 135.501 (-54.0221 -134.06)
Norm : 0.390830 (-0.0471429 0.0642403)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 51.27 using 59 PHA bins.
# Reduced chi-squared = 0.8994 for 57 degrees of freedom
# Null hypothesis probability = 6.890109e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.426e-07 2.236e-08
25- 50 2.603e-07 8.437e-08
50-150 4.919e-07 2.623e-07
15-150 8.948e-07 3.177e-07
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 7.47401 (-1.95699 1.88618)
R1^2/D10^2 : 0.104971 (-0.0573198 0.131207)
kT2 [keV] : 45.3403 (-23.4392 -45.9569)
R2^2/D10^2 : 1.96513E-04 (-0.00017591 0.000731042)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 48.86 using 59 PHA bins.
# Reduced chi-squared = 0.8884 for 55 degrees of freedom
# Null hypothesis probability = 7.067943e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.482e-07 4.901e-08
25- 50 2.666e-07 7.472e-08
50-150 5.686e-07 2.968e-07
15-150 9.833e-07 3.722e-07
Peak spectrum fit
Power-law model
Time interval is from 8.560 sec. to 9.560 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.636107 ( -0.659275 0.536512 )
Norm@50keV : 3.20303E-03 ( -0.00118135 0.00108534 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 48.88 using 59 PHA bins.
# Reduced chi-squared = 0.8575 for 57 degrees of freedom
# Null hypothesis probability = 7.693370e-01
Photon flux (15-150 keV) in 1 sec: 0.372433 ( -0.117295 0.119915 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.02646e-08 ( -1.19697e-08 1.20324e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 8.560 sec. to 9.560 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.301274 ( -4.10513 -0.301253 )
Epeak [keV] : 341.999 ( -341.987 -341.987 )
Norm@50keV : 4.25089E-03 ( -0.002137 0.0555803 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 48.81 using 59 PHA bins.
# Reduced chi-squared = 0.8717 for 56 degrees of freedom
# Null hypothesis probability = 7.410974e-01
Photon flux (15-150 keV) in 1 sec: 0.367096 ( -0.122961 0.123135 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.00502e-08 ( -1.23097e-08 1.21087e-08 ) ergs/cm2
Band function
Time interval is from 8.560 sec. to 9.560 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.617193 ( 0.617193 0.617193 )
beta : -0.636108 ( -0.535786 0.659298 )
Epeak [keV] : 17.4634 ( -17.4634 -17.4634 )
Norm@50keV : 4.72583E-03 ( -0.00256654 44430.2 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 48.88 using 59 PHA bins.
# Reduced chi-squared = 0.8887 for 55 degrees of freedom
# Null hypothesis probability = 7.062399e-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] : 31.8860 (-10.7836 27.7233)
R^2/D10^2 : 4.87858E-03 (-0.00487858 0.0116081)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 49.56 using 59 PHA bins.
# Reduced chi-squared = 0.8695 for 57 degrees of freedom
# Null hypothesis probability = 7.474172e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 7.468e-10 4.693e-10
25- 50 4.720e-09 2.864e-09
50-150 3.302e-08 1.967e-08
15-150 3.848e-08 2.332e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 200.000 ( )
Norm : 1.51198 (-0.503627 0.503584)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.76 using 59 PHA bins.
# Reduced chi-squared = 0.9958 for 57 degrees of freedom
# Null hypothesis probability = 4.839683e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 3.768e-09 2.438e-09
25- 50 7.249e-09 4.609e-09
50-150 1.590e-08 1.016e-08
15-150 2.691e-08 1.660e-08
Double BB
R1^2/D10^2 : 1.00090E+06 ( )
kT2 [keV] : 33.2580 (-11.677 30.3652)
R2^2/D10^2 : 4.29222E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 48.48 using 59 PHA bins.
#Fit statistic : Chi-Squared = 47.09 using 59 PHA bins.
#Fit statistic : Chi-Squared = 47.05 using 59 PHA bins.
# Reduced chi-squared = 0.8814 for 55 degrees of freedom
# Reduced chi-squared = 0.8562 for 55 degrees of freedom
# Reduced chi-squared = 0.8555 for 55 degrees of freedom
# Null hypothesis probability = 7.204003e-01
# Null hypothesis probability = 7.671402e-01
# Null hypothesis probability = 7.682627e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.914e-09 1.501e-09
25- 50 5.611e-09 2.936e-09
50-150 3.324e-08 1.840e-08
15-150 4.077e-08 2.285e-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: 1.28836 ( -0.167663 0.166003 )
Norm@50keV : 1.47690E-03 ( -0.000143516 0.000143294 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 50.35 using 59 PHA bins.
# Reduced chi-squared = 0.8833 for 57 degrees of freedom
# Null hypothesis probability = 7.209702e-01
Photon flux (15-150 keV) in 50.3 sec: 0.175825 ( -0.0173719 0.0173962 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.36206e-07 ( -7.97713e-08 8.0487e-08 ) ergs/cm2
Cutoff power-law model
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.841049 ( -0.806329 0.5468 )
Epeak [keV] : 131.289 ( )
Norm@50keV : 2.47553E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 49.13 using 59 PHA bins.
# Reduced chi-squared = 0.8774 for 56 degrees of freedom
# Null hypothesis probability = 7.302538e-01
Photon flux (15-150 keV) in 50.3 sec: 0.172584 ( -0.018194 0.01811 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.10186e-07 ( -9.11889e-08 9.03086e-08 ) ergs/cm2
Band function
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 1.68916 ( -1.14788 -1.14788 )
beta : -1.43244 ( 1.42982 0.234677 )
Epeak [keV] : 36.5147 ( -36.4122 61.5799 )
Norm@50keV : 0.157184 ( -0.163176 19.5596 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 48.22 using 59 PHA bins.
# Reduced chi-squared = 0.8768 for 55 degrees of freedom
# Null hypothesis probability = 7.292512e-01
Photon flux (15-150 keV) in 50.3 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) = 2.51e-07
S(50-100 keV) = 3.09e-07
T90 vs. Hardness ratio plot
T90 = 124 sec.
Hardness ratio (energy fluence ratio) = 1.23108
Color vs. Color plot
Count Ratio (25-50 keV) / (15-25 keV) = 1.06115
Count Ratio (50-100 keV) / (15-25 keV) = 0.648602
Mask shadow pattern
IMX = -4.205418108156107E-02, IMY = -2.571044896457641E-01
TIME vs. PHA plot around the trigger time
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 8.192000
TIME vs. DetID plot around the trigger time
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 8.192000
100 us light curve (15-350 keV)
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 8.192000
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:
-239.440000 -0.440000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
83.6280 22.0183 0.3 40.4 -147.3 10.4684 38.7 0.4 Crab
251.7999 68.4053 2.5 59.2 -14.9 4.9023 4.6 ------ UNKNOWN
354.5855 80.1076 3.2 50.6 -44.5 3.7166 3.6 ------ UNKNOWN
45.2588 69.9081 2.4 43.6 -63.8 3.9336 4.8 ------ UNKNOWN
54.2714 61.0232 2.4 41.6 -77.7 3.3838 4.9 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image:
-0.440000 49.860600
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
83.6220 22.0145 3.1 40.4 -147.3 -0.3851 -3.7 0.6 Crab
136.6322 35.1513 0.7 14.6 99.3 1.1812 16.2 ------ UNKNOWN
132.3332 49.0574 2.4 6.5 24.9 0.3181 4.9 ------ UNKNOWN
98.3740 8.3942 3.0 43.5 -176.5 0.4449 3.9 ------ UNKNOWN
89.5491 53.1424 2.2 23.0 -94.2 0.4310 5.2 ------ UNKNOWN
327.2766 80.9620 2.0 52.3 -39.1 1.8007 5.7 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image:
86.060600 962.593100
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
83.6295 22.0131 1.1 47.8 -129.5 19.5727 10.5 0.2 Crab
143.7080 3.0851 3.5 32.8 128.5 2.4500 3.3 ------ UNKNOWN
166.3879 29.5007 2.5 25.7 56.0 2.5993 4.7 ------ UNKNOWN
162.9601 47.6551 3.0 23.2 11.0 1.6423 3.9 ------ UNKNOWN
91.3281 -6.1606 3.0 59.4 -163.1 14.9524 3.8 ------ UNKNOWN
97.9275 42.5855 2.1 30.7 -102.6 3.1134 5.4 ------ UNKNOWN
91.3912 61.3984 3.2 38.6 -71.4 3.6111 3.6 ------ UNKNOWN
Plot creation:
Sun May 31 08:12:11 EDT 2015