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
11.2802 -1.5866 0.0140 32.7093 169.8710 0.1315246 13.775 TRIG_00382941
Foreground time interval of the image:
-0.008 0.316 (delta_t = 0.324 [sec])
Background time interval of the image:
-239.024 -0.008 (delta_t = 239.016 [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 0.064000
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 0.064000
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 0.064000
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 -0.008 sec. to 0.316 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.878879 ( -0.229124 0.217597 )
Norm@50keV : 2.54999E-02 ( -0.00339627 0.00335871 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 62.29 using 59 PHA bins.
# Reduced chi-squared = 1.093 for 57 degrees of freedom
# Null hypothesis probability = 2.934392e-01
Photon flux (15-150 keV) in 0.324 sec: 2.92663 ( -0.386472 0.387432 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.34918e-08 ( -1.26922e-08 1.27471e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.008 sec. to 0.316 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.629586 ( -1.01824 0.478812 )
Epeak [keV] : 331.096 ( -263.786 -263.786 )
Norm@50keV : 3.25825E-02 ( -0.0125267 0.0506601 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 61.86 using 59 PHA bins.
# Reduced chi-squared = 1.105 for 56 degrees of freedom
# Null hypothesis probability = 2.749394e-01
Photon flux (15-150 keV) in 0.324 sec: 2.89678 ( -0.19763 0.39449 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.26543e-08 ( -1.30925e-08 1.30157e-08 ) ergs/cm2
Band function
Time interval is from -0.008 sec. to 0.316 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 5.00000 ( -5 -5 )
beta : -0.963602 ( -0.258771 0.254075 )
Epeak [keV] : 29.7645 ( -29.7629 9.68302 )
Norm@50keV : 590.062 ( -74.5672 3.75213e+06 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 60.85 using 59 PHA bins.
# Reduced chi-squared = 1.106 for 55 degrees of freedom
# Null hypothesis probability = 2.736028e-01
Photon flux (15-150 keV) in 0.324 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] : 25.3930 (-4.03069 5.33013)
R^2/D10^2 : 7.03195E-02 (-0.030722 0.0496013)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 69.62 using 59 PHA bins.
# Reduced chi-squared = 1.221 for 57 degrees of freedom
# Null hypothesis probability = 1.218781e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.531e-09 6.948e-10
25- 50 1.447e-08 3.114e-09
50-150 6.903e-08 1.528e-08
15-150 8.603e-08 1.934e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 200.000 ( )
Norm : 11.6660 (-1.60157 1.60152)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 87.09 using 59 PHA bins.
# Reduced chi-squared = 1.528 for 57 degrees of freedom
# Null hypothesis probability = 6.298194e-03
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 9.413e-09 5.301e-09
25- 50 1.811e-08 1.029e-08
50-150 3.971e-08 2.249e-08
15-150 6.724e-08 3.810e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 6.89265 (-2.49892 4.51236)
R1^2/D10^2 : 1.90801 (-1.57699 7.62582)
kT2 [keV] : 33.5348 (-7.62548 18.0332)
R2^2/D10^2 : 2.76270E-02 (-0.0195698 0.0342574)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.85 using 59 PHA bins.
# Reduced chi-squared = 1.088 for 55 degrees of freedom
# Null hypothesis probability = 3.041811e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 6.109e-09 3.468e-09
25- 50 1.561e-08 7.841e-09
50-150 7.221e-08 3.963e-08
15-150 9.393e-08 4.621e-08
Peak spectrum fit
Power-law model
Time interval is from -0.344 sec. to 0.656 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.915957 ( -0.356974 0.32875 )
Norm@50keV : 8.35252E-03 ( -0.00162185 0.00158356 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.39 using 59 PHA bins.
# Reduced chi-squared = 0.9894 for 57 degrees of freedom
# Null hypothesis probability = 4.977762e-01
Photon flux (15-150 keV) in 1 sec: 0.958888 ( -0.184363 0.185486 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.31611e-08 ( -1.78676e-08 1.79894e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.344 sec. to 0.656 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.15267 ( )
Epeak [keV] : 51.0547 ( )
Norm@50keV : 6.61990E-04 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.17 using 59 PHA bins.
# Reduced chi-squared = 1.003 for 56 degrees of freedom
# Null hypothesis probability = 4.683124e-01
Photon flux (15-150 keV) in 1 sec: 0.960418 ( -0.187261 0.183772 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.31305e-08 ( -1.78415e-08 1.79495e-08 ) ergs/cm2
Band function
Time interval is from -0.344 sec. to 0.656 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.798522 ( 0.798521 0.798521 )
beta : -0.915957 ( -0.328757 0.357405 )
Epeak [keV] : 33.7172 ( -33.7257 -33.7257 )
Norm@50keV : 1.29275E-02 ( -0.0061045 0 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.39 using 59 PHA bins.
# Reduced chi-squared = 1.025 for 55 degrees of freedom
# Null hypothesis probability = 4.225869e-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] : 25.8977 (-6.09377 9.60295)
R^2/D10^2 : 2.09814E-02 (-0.0126714 0.0272022)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 62.55 using 59 PHA bins.
# Reduced chi-squared = 1.097 for 57 degrees of freedom
# Null hypothesis probability = 2.858928e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.398e-09 9.435e-10
25- 50 1.385e-08 5.335e-09
50-150 6.847e-08 2.608e-08
15-150 8.472e-08 2.796e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 200.000 ( )
Norm : 3.96019 (-0.766086 0.765995)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 66.89 using 59 PHA bins.
# Reduced chi-squared = 1.173 for 57 degrees of freedom
# Null hypothesis probability = 1.738415e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 9.861e-09 5.760e-09
25- 50 1.897e-08 1.118e-08
50-150 4.160e-08 2.381e-08
15-150 7.043e-08 4.056e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 8.20626 (-4.24934 7.91292)
R1^2/D10^2 : 0.434086 (-0.374612 5.53832)
kT2 [keV] : 41.9420 (-20.0279 -41.9523)
R2^2/D10^2 : 4.52185E-03 (-0.00440623 0.0152747)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 55.92 using 59 PHA bins.
# Reduced chi-squared = 1.017 for 55 degrees of freedom
# Null hypothesis probability = 4.402041e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 6.375e-09 3.795e-09
25- 50 1.670e-08 9.060e-09
50-150 7.220e-08 4.064e-08
15-150 9.527e-08 4.880e-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: 0.878879 ( -0.229124 0.217597 )
Norm@50keV : 2.54999E-02 ( -0.00339627 0.00335871 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 62.29 using 59 PHA bins.
# Reduced chi-squared = 1.093 for 57 degrees of freedom
# Null hypothesis probability = 2.934392e-01
Photon flux (15-150 keV) in 0.324 sec: 2.92663 ( -0.386472 0.387432 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.34918e-08 ( -1.26922e-08 1.27471e-08 ) ergs/cm2
Cutoff power-law model
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.629586 ( -1.01824 0.478812 )
Epeak [keV] : 331.096 ( -263.786 -263.786 )
Norm@50keV : 3.25825E-02 ( -0.0125267 0.0506601 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 61.86 using 59 PHA bins.
# Reduced chi-squared = 1.105 for 56 degrees of freedom
# Null hypothesis probability = 2.749394e-01
Photon flux (15-150 keV) in 0.324 sec: 2.89678 ( -0.19763 0.39449 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.26543e-08 ( -1.30925e-08 1.30157e-08 ) ergs/cm2
Band function
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 5.00000 ( -5 -5 )
beta : -0.963602 ( -0.258771 0.254075 )
Epeak [keV] : 29.7645 ( -29.7629 9.68302 )
Norm@50keV : 590.062 ( -74.5672 3.75213e+06 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 60.85 using 59 PHA bins.
# Reduced chi-squared = 1.106 for 55 degrees of freedom
# Null hypothesis probability = 2.736028e-01
Photon flux (15-150 keV) in 0.324 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) = 1.59e-08
S(50-100 keV) = 3.47e-08
T90 vs. Hardness ratio plot
T90 = 0.291999936103821 sec.
Hardness ratio (energy fluence ratio) = 2.18239
Color vs. Color plot
Count Ratio (25-50 keV) / (15-25 keV) = 1.65716
Count Ratio (50-100 keV) / (15-25 keV) = 2.46258
Mask shadow pattern
IMX = -6.322094570189947E-01, IMY = -1.129433774141745E-01
TIME vs. PHA plot around the trigger time
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 0.064000
TIME vs. DetID plot around the trigger time
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 0.064000
100 us light curve (15-350 keV)
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 0.064000
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:
-239.024000 -0.008000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
288.7678 10.9322 9.6 53.3 -38.8 1.1815 1.2 2.0 GRS 1915+105
299.5802 35.2070 0.4 43.4 -6.0 11.3969 32.0 0.6 Cyg X-1
308.1440 40.9493 3.0 39.2 5.8 1.1632 3.8 1.5 Cyg X-3
325.9324 38.3095 6.4 27.0 18.0 0.4033 1.8 11.3 Cyg X-2
21.7346 -15.4813 2.7 49.3 177.6 1.9788 4.3 ------ UNKNOWN
23.2629 -25.9129 3.2 57.2 -173.7 4.0230 3.7 ------ UNKNOWN
23.4923 -27.7317 3.3 58.6 -172.3 4.8972 3.6 ------ UNKNOWN
19.5304 -31.7290 2.4 59.1 -166.2 7.6029 4.9 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image:
-0.008000 0.316000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
288.7896 11.0813 3.3 53.2 -38.6 0.1187 3.5 8.2 GRS 1915+105
299.6337 35.0885 3.9 43.4 -6.1 0.0369 2.9 7.1 Cyg X-1
308.1463 40.9835 33.0 39.3 5.9 0.0038 0.3 2.5 Cyg X-3
326.2377 38.1341 0.0 26.7 18.2 0.0065 0.8 11.7 Cyg X-2
11.2802 -1.5866 0.8 32.7 169.9 0.1316 13.8 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image:
68.676590 663.136000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
326.1423 38.1425 7.6 57.5 -20.0 2.0527 1.5 10.8 Cyg X-2
10.4314 36.4025 2.6 38.0 20.3 1.9276 4.4 ------ UNKNOWN
343.9329 34.6366 2.4 44.3 -11.4 2.0767 4.8 ------ UNKNOWN
29.5502 -57.0324 3.7 57.4 -170.3 4.1367 3.1 ------ UNKNOWN
355.5916 -30.4899 4.5 32.5 -133.0 1.0504 2.6 ------ UNKNOWN
332.5299 -16.6145 3.0 41.0 -92.5 5.8228 3.8 ------ UNKNOWN
Plot creation:
Sun May 31 02:21:45 EDT 2015