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
252.5307 31.5930 0.0154 29.8132 160.1590 1.3961792 12.474 TRIG_00223217
Foreground time interval of the image:
-40.772 25.760 (delta_t = 66.532 [sec])
Background time interval of the image:
-239.768 -40.772 (delta_t = 198.996 [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)
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 -40.772 sec. to 25.760 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.53657 ( -0.197573 0.200001 )
Norm@50keV : 1.37622E-03 ( -0.000158872 0.000157221 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.54 using 59 PHA bins.
# Reduced chi-squared = 1.027 for 57 degrees of freedom
# Null hypothesis probability = 4.187175e-01
Photon flux (15-150 keV) in 66.53 sec: 0.173552 ( -0.0191898 0.0192214 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.63646e-07 ( -1.08858e-07 1.1052e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -40.772 sec. to 25.760 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.40750 ( -0.891163 1.15225 )
Epeak [keV] : 217.148 ( -220.757 -220.757 )
Norm@50keV : 1.61083E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.46 using 59 PHA bins.
# Reduced chi-squared = 1.044 for 56 degrees of freedom
# Null hypothesis probability = 3.850951e-01
Photon flux (15-150 keV) in 66.53 sec: 0.172496 ( -0.020253 0.010069 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.52875e-07 ( -1.29893e-07 1.19248e-07 ) ergs/cm2
Band function
Time interval is from -40.772 sec. to 25.760 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.557729 ( 0.810573 5.68172 )
beta : -1.68879 ( 1.67865 0.312118 )
Epeak [keV] : 52.2324 ( -51.5636 113.421 )
Norm@50keV : 5.54677E-03 ( -0.00594159 167988 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.79 using 59 PHA bins.
# Reduced chi-squared = 1.051 for 55 degrees of freedom
# Null hypothesis probability = 3.726901e-01
Photon flux (15-150 keV) in 66.53 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] : 13.2192 (-1.76219 2.14966)
R^2/D10^2 : 3.00084E-02 (-0.0124989 0.0202664)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 76.10 using 59 PHA bins.
# Reduced chi-squared = 1.335 for 57 degrees of freedom
# Null hypothesis probability = 4.630119e-02
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 7.397e-08 1.479e-08
25- 50 2.593e-07 3.862e-08
50-150 2.893e-07 7.002e-08
15-150 6.226e-07 9.291e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 199.114 (-84.7791 -199.197)
Norm : 0.705745 (-0.0764422 0.0774485)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.54 using 59 PHA bins.
# Reduced chi-squared = 1.027 for 57 degrees of freedom
# Null hypothesis probability = 4.187013e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.169e-07 6.567e-08
25- 50 2.249e-07 1.227e-07
50-150 4.931e-07 2.686e-07
15-150 8.349e-07 4.527e-07
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 8.94378 (-2.4149 2.40504)
R1^2/D10^2 : 9.48102E-02 (-0.0491652 0.145433)
kT2 [keV] : 45.2142 (-23.9371 -46.9604)
R2^2/D10^2 : 3.51028E-04 (-0.000307863 0.00282206)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.49 using 59 PHA bins.
# Reduced chi-squared = 1.045 for 55 degrees of freedom
# Null hypothesis probability = 3.832305e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.035e-07 3.887e-08
25- 50 2.458e-07 8.898e-08
50-150 5.146e-07 2.725e-07
15-150 8.639e-07 3.720e-07
Peak spectrum fit
Power-law model
Time interval is from -0.140 sec. to 0.860 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.16059 ( -0.341981 0.331962 )
Norm@50keV : 7.05673E-03 ( -0.00133362 0.00133155 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 36.11 using 59 PHA bins.
# Reduced chi-squared = 0.6334 for 57 degrees of freedom
# Null hypothesis probability = 9.861228e-01
Photon flux (15-150 keV) in 1 sec: 0.824021 ( -0.160142 0.160823 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.24146e-08 ( -1.50134e-08 1.52215e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.140 sec. to 0.860 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.533179 ( -2.15436 0.924655 )
Epeak [keV] : 129.050 ( -128.979 -128.979 )
Norm@50keV : 1.37121E-02 ( -0.00781274 0.106634 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 35.61 using 59 PHA bins.
# Reduced chi-squared = 0.6359 for 56 degrees of freedom
# Null hypothesis probability = 9.847092e-01
Photon flux (15-150 keV) in 1 sec: 0.799665 ( -0.17481 0.170957 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.97674e-08 ( -1.68624e-08 1.6543e-08 ) ergs/cm2
Band function
Time interval is from -0.140 sec. to 0.860 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.480043 ( 0.924302 0.924302 )
beta : -1.60252 ( 1.58329 0.726337 )
Epeak [keV] : 118.111 ( -113.67 488.448 )
Norm@50keV : 1.48075E-02 ( -0.0096804 0 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 35.56 using 59 PHA bins.
# Reduced chi-squared = 0.6465 for 55 degrees of freedom
# Null hypothesis probability = 9.806302e-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] : 19.0447 (-3.89702 5.52505)
R^2/D10^2 : 4.54403E-02 (-0.025728 0.0518755)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 37.95 using 59 PHA bins.
# Reduced chi-squared = 0.6659 for 57 degrees of freedom
# Null hypothesis probability = 9.755160e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 3.237e-09 1.416e-09
25- 50 1.559e-08 5.226e-09
50-150 4.159e-08 1.538e-08
15-150 6.042e-08 2.140e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 200.000 ( )
Norm : 3.40870 (-0.658701 0.658647)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 39.68 using 59 PHA bins.
# Reduced chi-squared = 0.6961 for 57 degrees of freedom
# Null hypothesis probability = 9.607396e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 8.492e-09 4.946e-09
25- 50 1.634e-08 9.515e-09
50-150 3.583e-08 2.051e-08
15-150 6.065e-08 3.568e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 2.17030 (-1.71395 10.5688)
R1^2/D10^2 : 181.635 (-178.849 -178.939)
kT2 [keV] : 20.7448 (-4.49914 6.88196)
R2^2/D10^2 : 3.32208E-02 (-0.0200705 0.0399007)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 33.76 using 59 PHA bins.
# Reduced chi-squared = 0.6138 for 55 degrees of freedom
# Null hypothesis probability = 9.893215e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 6.057e-09 2.582e-09
25- 50 1.398e-08 6.832e-09
50-150 4.437e-08 1.967e-08
15-150 6.441e-08 2.668e-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: 1.53657 ( -0.197573 0.200001 )
Norm@50keV : 1.37622E-03 ( -0.000158872 0.000157221 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.54 using 59 PHA bins.
# Reduced chi-squared = 1.027 for 57 degrees of freedom
# Null hypothesis probability = 4.187175e-01
Photon flux (15-150 keV) in 66.53 sec: 0.173552 ( -0.0191898 0.0192214 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.63646e-07 ( -1.08858e-07 1.1052e-07 ) ergs/cm2
Cutoff power-law model
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.40750 ( -0.891163 1.15225 )
Epeak [keV] : 217.148 ( -220.757 -220.757 )
Norm@50keV : 1.61083E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.46 using 59 PHA bins.
# Reduced chi-squared = 1.044 for 56 degrees of freedom
# Null hypothesis probability = 3.850951e-01
Photon flux (15-150 keV) in 66.53 sec: 0.172496 ( -0.020253 0.010069 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.52875e-07 ( -1.29893e-07 1.19248e-07 ) ergs/cm2
Band function
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.557729 ( 0.810573 5.68172 )
beta : -1.68879 ( 1.67865 0.312118 )
Epeak [keV] : 52.2324 ( -51.5636 113.715 )
Norm@50keV : 5.54677E-03 ( -0.00594159 167988 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.79 using 59 PHA bins.
# Reduced chi-squared = 1.051 for 55 degrees of freedom
# Null hypothesis probability = 3.726901e-01
Photon flux (15-150 keV) in 66.53 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) = 2.17e-07
S(50-100 keV) = 3.00e-07
T90 vs. Hardness ratio plot
T90 = 54.0480000078678 sec.
Hardness ratio (energy fluence ratio) = 1.38249
Color vs. Color plot
Count Ratio (25-50 keV) / (15-25 keV) = 1.68622
Count Ratio (50-100 keV) / (15-25 keV) = 1.07286
Mask shadow pattern
IMX = -5.389973028856305E-01, IMY = -1.944870707172092E-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:
-239.768000 -40.772000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
254.3678 35.3088 4.6 25.8 160.1 0.5107 2.5 4.8 Her X-1
299.5944 35.2071 0.4 29.1 74.5 7.7860 28.0 0.4 Cyg X-1
308.0500 40.9792 2.9 28.2 56.1 0.9674 3.9 3.2 Cyg X-3
326.0224 38.4147 6.2 39.3 40.5 0.7142 1.9 9.0 Cyg X-2
308.0634 37.6373 0.5 30.8 60.4 7.2458 24.9 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image:
-40.772000 25.760000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
254.4563 35.5381 0.0 25.6 160.1 -0.1765 -1.6 11.7 Her X-1
299.4910 35.0682 4.8 29.2 74.7 -0.3471 -2.4 9.4 Cyg X-1
308.1142 40.9913 4.1 28.2 56.0 -0.3693 -2.8 2.3 Cyg X-3
325.9695 38.2541 5.2 39.4 40.7 -0.4427 -2.2 10.3 Cyg X-2
279.2647 25.7750 2.2 32.7 113.0 0.9339 5.4 ------ UNKNOWN
318.8759 49.3957 2.0 28.1 32.0 0.6394 5.8 ------ UNKNOWN
338.1975 49.0665 2.9 38.4 18.5 0.5614 4.0 ------ UNKNOWN
252.5307 31.5930 0.9 29.8 160.2 1.3963 12.5 ------ UNKNOWN
7.5275 75.4393 2.0 35.9 -30.3 0.6872 5.8 ------ UNKNOWN
14.6417 78.2925 2.1 36.0 -35.9 0.6305 5.4 ------ UNKNOWN
204.1519 58.2708 2.2 34.4 -115.4 0.7547 5.2 ------ UNKNOWN
203.4386 27.6232 2.4 55.9 -147.3 2.5808 4.9 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image:
90.532600 556.594700
557.232000 962.252000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
244.9862 -15.6451 0.5 47.8 162.3 36.4466 24.5 0.5 Sco X-1
254.2710 35.3272 94.1 4.0 -6.4 -0.0601 -0.1 9.2 Her X-1
268.2242 -1.4748 7.4 36.3 125.3 1.9469 1.6 8.7 SW J1753.5-0127
288.8172 10.9567 2.7 39.3 86.0 9.2598 4.3 1.3 GRS 1915+105
299.5938 35.2035 0.4 39.1 44.1 32.0165 29.6 0.2 Cyg X-1
308.0541 40.9533 2.9 45.0 34.3 5.5950 4.0 2.5 Cyg X-3
308.0814 37.6435 0.6 45.5 38.9 28.3522 17.7 ------ UNKNOWN
268.6084 25.7615 2.6 15.3 81.0 2.1580 4.4 ------ UNKNOWN
265.2415 52.4874 3.1 22.8 -7.3 1.7203 3.7 ------ UNKNOWN
Plot creation:
Sun May 31 12:22:27 EDT 2015