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
153.7097 -62.3547 0.0050 10.5113 -89.4606 2.6487573 38.064 TRIG_00542441
Foreground time interval of the image:
-17.732 20.813 (delta_t = 38.545 [sec])
Background time interval of the image:
-239.888 -17.732 (delta_t = 222.156 [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)
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 -17.732 sec. to 783.760 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.54024 ( -0.082591 0.0828057 )
Norm@50keV : 8.15804E-04 ( -3.62652e-05 3.61498e-05 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 53.36 using 59 PHA bins.
# Reduced chi-squared = 0.9362 for 57 degrees of freedom
# Null hypothesis probability = 6.123453e-01
Photon flux (15-150 keV) in 801.5 sec: 0.102987 ( -0.00470812 0.00472266 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.16428e-06 ( -2.97123e-07 2.98503e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -17.732 sec. to 783.760 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.53658 ( -0.308399 0.0846115 )
Epeak [keV] : 9874.59 ( -9761.51 -9761.51 )
Norm@50keV : 8.18181E-04 ( -3.55199e-05 0.000334567 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 53.36 using 59 PHA bins.
# Reduced chi-squared = 0.9529 for 56 degrees of freedom
# Null hypothesis probability = 5.753287e-01
Photon flux (15-150 keV) in 801.5 sec: 0.102945 ( -0.00471 0.004712 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.16463e-06 ( -3.36774e-07 2.96475e-07 ) ergs/cm2
Band function
Time interval is from -17.732 sec. to 783.760 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.05853 ( 1.04763 1.04763 )
beta : -1.57790 ( 1.57952 0.111525 )
Epeak [keV] : 63.9746 ( -62.9407 -62.9407 )
Norm@50keV : 1.65887E-03 ( -0.000947378 0 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 52.73 using 59 PHA bins.
# Reduced chi-squared = 0.9587 for 55 degrees of freedom
# Null hypothesis probability = 5.619122e-01
Photon flux (15-150 keV) in 801.5 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] : 14.9171 ( )
R^2/D10^2 : 1.12641E-02 ( )
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 193.00 using 59 PHA bins.
# Reduced chi-squared = 3.3859 for 57 degrees of freedom
# Null hypothesis probability = 1.122680e-16
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 4.210e-07 3.875e-08
25- 50 1.664e-06 1.074e-07
50-150 2.514e-06 2.384e-07
15-150 4.599e-06 2.272e-07
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 200.000 ( )
Norm : 0.417342 (-0.0181438 0.0181379)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.21 using 59 PHA bins.
# Reduced chi-squared = 0.9861 for 57 degrees of freedom
# Null hypothesis probability = 5.047132e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 8.332e-07 4.168e-08
25- 50 1.603e-06 7.694e-08
50-150 3.515e-06 1.703e-07
15-150 5.951e-06 3.082e-07
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 7.35325 (-0.904126 0.972104)
R1^2/D10^2 : 9.66844E-02 (-0.0331235 0.0563826)
kT2 [keV] : 30.3335 (-4.6262 7.10568)
R2^2/D10^2 : 7.74299E-04 (-0.000380395 0.0005963)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 52.42 using 59 PHA bins.
# Reduced chi-squared = 0.9532 for 55 degrees of freedom
# Null hypothesis probability = 5.736801e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 7.951e-07 1.010e-07
25- 50 1.612e-06 1.940e-07
50-150 3.767e-06 6.953e-07
15-150 6.175e-06 8.632e-07
Peak spectrum fit
Power-law model
Time interval is from 735.960 sec. to 736.960 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.47906 ( -0.145995 0.147292 )
Norm@50keV : 1.41262E-02 ( -0.00121124 0.00120423 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.41 using 59 PHA bins.
# Reduced chi-squared = 0.9545 for 57 degrees of freedom
# Null hypothesis probability = 5.729084e-01
Photon flux (15-150 keV) in 1 sec: 1.75377 ( -0.146873 0.146993 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.3448e-07 ( -1.27519e-08 1.28701e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 735.960 sec. to 736.960 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.33185 ( -0.568879 0.279585 )
Epeak [keV] : 226.196 ( -226.195 -226.195 )
Norm@50keV : 1.67926E-02 ( -0.00523183 0.0153097 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.17 using 59 PHA bins.
# Reduced chi-squared = 0.9674 for 56 degrees of freedom
# Null hypothesis probability = 5.442550e-01
Photon flux (15-150 keV) in 1 sec: 1.74232 ( -0.1521 0.14812 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.32965e-07 ( -1.399e-08 1.3865e-08 ) ergs/cm2
Band function
Time interval is from 735.960 sec. to 736.960 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.33234 ( 0.927172 0.927172 )
beta : -9.36765 ( 9.37047 19.3562 )
Epeak [keV] : 226.963 ( -116.807 -226.966 )
Norm@50keV : 1.67801E-02 ( -0.00377237 0.00748542 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.17 using 59 PHA bins.
# Reduced chi-squared = 0.9850 for 55 degrees of freedom
# Null hypothesis probability = 5.061373e-01
Photon flux (15-150 keV) in 1 sec: 1.73616 ( ) 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] : 15.0848 (-1.67824 1.92733)
R^2/D10^2 : 0.192548 (-0.0654512 0.0979588)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 92.98 using 59 PHA bins.
# Reduced chi-squared = 1.631 for 57 degrees of freedom
# Null hypothesis probability = 1.842246e-03
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 9.165e-09 1.483e-09
25- 50 3.660e-08 4.345e-09
50-150 5.683e-08 1.005e-08
15-150 1.026e-07 1.050e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 200.000 ( )
Norm : 7.15663 (-0.592239 0.592239)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 55.10 using 59 PHA bins.
# Reduced chi-squared = 0.9667 for 57 degrees of freedom
# Null hypothesis probability = 5.466830e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.787e-08 1.845e-09
25- 50 3.438e-08 9.020e-09
50-150 7.541e-08 3.173e-08
15-150 1.277e-07 4.340e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 6.48347 (-1.64263 2.0536)
R1^2/D10^2 : 2.34634 (-1.39759 4.50873)
kT2 [keV] : 26.1370 (-5.54768 11.1221)
R2^2/D10^2 : 2.37057E-02 (-0.0165184 0.0323818)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.53 using 59 PHA bins.
# Reduced chi-squared = 0.9915 for 55 degrees of freedom
# Null hypothesis probability = 4.924288e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.728e-08 7.465e-09
25- 50 3.300e-08 1.013e-08
50-150 8.220e-08 3.264e-08
15-150 1.325e-07 4.803e-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: 1.45169 ( -0.0751383 0.0751838 )
Norm@50keV : 4.41653E-03 ( -0.000178319 0.000178121 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 50.27 using 59 PHA bins.
# Reduced chi-squared = 0.8819 for 57 degrees of freedom
# Null hypothesis probability = 7.237809e-01
Photon flux (15-150 keV) in 38.54 sec: 0.544508 ( -0.0229967 0.0230385 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.62831e-06 ( -7.18898e-08 7.21638e-08 ) ergs/cm2
Cutoff power-law model
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.30977 ( -0.296114 0.179097 )
Epeak [keV] : 255.314 ( -255.314 -255.314 )
Norm@50keV : 5.16714E-03 ( -0.00105891 0.0019358 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 49.53 using 59 PHA bins.
# Reduced chi-squared = 0.8844 for 56 degrees of freedom
# Null hypothesis probability = 7.168313e-01
Photon flux (15-150 keV) in 38.54 sec: 0.539580 ( -0.024828 0.024553 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.61101e-06 ( -8.06642e-08 7.57003e-08 ) ergs/cm2
Band function
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.708347 ( 0.967434 5.96706 )
beta : -1.48531 ( 1.48331 0.0950591 )
Epeak [keV] : 52.1978 ( -52.0376 -52.0376 )
Norm@50keV : 1.39077E-02 ( -0.0142838 435726 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 49.41 using 59 PHA bins.
# Reduced chi-squared = 0.8983 for 55 degrees of freedom
# Null hypothesis probability = 6.873734e-01
Photon flux (15-150 keV) in 38.54 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) = 1.55e-06
S(50-100 keV) = 2.14e-06
T90 vs. Hardness ratio plot
T90 = 778.091999948025 sec.
Hardness ratio (energy fluence ratio) = 1.38065
Color vs. Color plot
Count Ratio (25-50 keV) / (15-25 keV) = 1.30503
Count Ratio (50-100 keV) / (15-25 keV) = 0.944857
Mask shadow pattern
IMX = 1.746644344066289E-03, IMY = 1.855342398251260E-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:
-239.888000 -17.732000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
135.4886 -40.5192 3.2 14.8 121.6 0.6720 3.6 2.8 Vela X-1
170.4629 -60.6805 2.5 17.5 -107.3 0.7999 4.5 5.5 Cen X-3
186.6455 -62.7692 3.2 25.1 -101.6 0.7818 3.6 0.3 GX 301-2
152.4723 -58.2919 0.9 8.1 -110.3 2.0253 12.3 ------ UNKNOWN
170.6289 -83.4685 2.5 29.5 -55.6 0.9531 4.7 ------ UNKNOWN
6.4332 -60.1006 2.9 58.7 -23.0 4.6042 4.0 ------ UNKNOWN
231.9109 -72.4875 3.4 39.3 -76.9 1.7725 3.4 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image:
-17.732000 20.812600
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
135.4545 -40.6807 4.7 14.7 121.4 0.1856 2.5 8.3 Vela X-1
170.3584 -60.6167 76.6 17.4 -107.5 -0.0113 -0.2 1.3 Cen X-3
186.3500 -62.6767 10.3 25.0 -101.8 0.0969 1.1 10.1 GX 301-2
178.1838 -7.1342 2.4 57.3 179.9 2.0865 4.9 ------ UNKNOWN
153.7097 -62.3547 0.3 10.5 -89.5 2.6488 38.1 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image:
53.212600 962.146000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
135.5232 -40.5249 1.8 24.4 115.5 4.3323 6.4 1.8 Vela X-1
170.3456 -60.5629 2.6 8.1 -124.4 2.0298 4.4 3.7 Cen X-3
186.6465 -62.7781 0.8 15.0 -103.0 6.6862 14.8 0.5 GX 301-2
107.7877 -36.1130 3.0 38.5 81.7 8.0388 3.8 ------ UNKNOWN
152.4342 -58.2890 0.6 4.1 141.2 10.2037 20.5 ------ UNKNOWN
153.6992 -62.3570 0.6 0.0 -36.6 9.0901 19.3 ------ UNKNOWN
16.4879 -62.1612 2.8 51.4 -5.5 5.2943 4.2 ------ UNKNOWN
6.1281 -65.7580 2.7 49.7 -12.7 4.2732 4.2 ------ UNKNOWN
190.2856 -9.4799 3.2 59.1 -166.2 10.3911 3.6 ------ UNKNOWN
333.1831 -68.4054 3.0 49.3 -29.7 3.9298 3.8 ------ UNKNOWN
Plot creation:
Sat May 30 17:39:47 EDT 2015