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
254.2184 55.2942 0.0141 18.8324 -56.3924 0.3239575 13.579 TRIG_00279592
Foreground time interval of the image:
-1.784 4.504 (delta_t = 6.288 [sec])
Background time interval of the image:
-239.168 -1.784 (delta_t = 237.384 [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)
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 -1.784 sec. to 4.504 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.01088 ( -0.220264 0.234422 )
Norm@50keV : 2.88590E-03 ( -0.000449007 0.000436878 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 66.44 using 59 PHA bins.
# Reduced chi-squared = 1.166 for 57 degrees of freedom
# Null hypothesis probability = 1.838341e-01
Photon flux (15-150 keV) in 6.288 sec: 0.435065 ( -0.0499352 0.0499364 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.67445e-07 ( -2.39201e-08 2.46254e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -1.784 sec. to 4.504 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.83745 ( -1.08502 0.297222 )
Epeak [keV] : 37.4692 ( )
Norm@50keV : 3.66387E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 66.32 using 59 PHA bins.
# Reduced chi-squared = 1.184 for 56 degrees of freedom
# Null hypothesis probability = 1.626829e-01
Photon flux (15-150 keV) in 6.288 sec: 0.432022 ( -0.052245 0.051747 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.63734e-07 ( -2.98498e-08 2.76471e-08 ) ergs/cm2
Band function
Time interval is from -1.784 sec. to 4.504 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.113151 ( -0.857107 -0.857107 )
beta : -2.12245 ( -1.50861 0.302247 )
Epeak [keV] : 25.3515 ( -23.6392 177.473 )
Norm@50keV : 7.40466E-02 ( -0.0720582 826.762 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 65.85 using 59 PHA bins.
# Reduced chi-squared = 1.197 for 55 degrees of freedom
# Null hypothesis probability = 1.500692e-01
Photon flux (15-150 keV) in 6.288 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] : 9.17404 (-1.19884 1.39252)
R^2/D10^2 : 0.278165 (-0.117539 0.201924)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 81.55 using 59 PHA bins.
# Reduced chi-squared = 1.431 for 57 degrees of freedom
# Null hypothesis probability = 1.812852e-02
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.894e-08 5.744e-09
25- 50 6.336e-08 1.038e-08
50-150 2.562e-08 9.001e-09
15-150 1.179e-07 1.886e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 62.3483 (-19.4628 35.2178)
Norm : 2.23372 (-0.411143 0.513644)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 67.05 using 59 PHA bins.
# Reduced chi-squared = 1.176 for 57 degrees of freedom
# Null hypothesis probability = 1.704412e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 3.551e-08 5.074e-09
25- 50 5.468e-08 7.920e-09
50-150 6.420e-08 2.233e-08
15-150 1.544e-07 2.584e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 6.05404 (-2.80462 2.43505)
R1^2/D10^2 : 1.06179 (-0.668362 9.89755)
kT2 [keV] : 22.2227 (-11.1961 -22.8253)
R2^2/D10^2 : 6.21664E-03 (-0.00545125 0.0775377)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 67.87 using 59 PHA bins.
# Reduced chi-squared = 1.234 for 55 degrees of freedom
# Null hypothesis probability = 1.140778e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 3.649e-08 1.832e-08
25- 50 5.240e-08 2.571e-08
50-150 7.299e-08 4.259e-08
15-150 1.619e-07 7.900e-08
Peak spectrum fit
Power-law model
Time interval is from 0.124 sec. to 1.124 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.01107 ( -0.344691 0.383347 )
Norm@50keV : 4.42239E-03 ( -0.00115084 0.00110643 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.73 using 59 PHA bins.
# Reduced chi-squared = 1.048 for 57 degrees of freedom
# Null hypothesis probability = 3.767720e-01
Photon flux (15-150 keV) in 1 sec: 0.666759 ( -0.124298 0.124312 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.08076e-08 ( -9.5768e-09 1.00723e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.124 sec. to 1.124 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.80780 ( -2.44749 0.315987 )
Epeak [keV] : 36.3499 ( )
Norm@50keV : 5.90217E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.66 using 59 PHA bins.
# Reduced chi-squared = 1.065 for 56 degrees of freedom
# Null hypothesis probability = 3.441603e-01
Photon flux (15-150 keV) in 1 sec: 0.662284 ( -0.125045 0.126904 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.96615e-08 ( -1.23414e-08 1.10316e-08 ) ergs/cm2
Band function
Time interval is from 0.124 sec. to 1.124 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 1.25717 ( -4.69845 -1.31267 )
beta : -2.27343 ( 2.27532 0.532664 )
Epeak [keV] : 25.8514 ( -25.6969 62.1633 )
Norm@50keV : 1.14914 ( -1.63485 465.769 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.62 using 59 PHA bins.
# Reduced chi-squared = 1.066 for 55 degrees of freedom
# Null hypothesis probability = 3.442675e-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] : 8.15087 (-1.49245 1.90893)
R^2/D10^2 : 0.688045 (-0.388737 0.839038)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 63.49 using 59 PHA bins.
# Reduced chi-squared = 1.114 for 57 degrees of freedom
# Null hypothesis probability = 2.583385e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 8.378e-09 3.115e-09
25- 50 1.514e-08 5.174e-09
50-150 4.227e-09 2.526e-09
15-150 2.775e-08 8.285e-09
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 59.0549 (-26.3492 71.1634)
Norm : 3.52604 (-0.98632 1.50195)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.91 using 59 PHA bins.
# Reduced chi-squared = 1.051 for 57 degrees of freedom
# Null hypothesis probability = 3.706741e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 8.839e-09 2.205e-09
25- 50 1.339e-08 3.738e-09
50-150 1.503e-08 9.053e-09
15-150 3.726e-08 1.294e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 6.76562 (-1.77835 1.87747)
R1^2/D10^2 : 1.24328 (-0.749713 2.55169)
kT2 [keV] : 36.0791 (-20.4202 -36.4565)
R2^2/D10^2 : 1.83288E-03 (-0.00176588 0.0274295)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.21 using 59 PHA bins.
# Reduced chi-squared = 1.040 for 55 degrees of freedom
# Null hypothesis probability = 3.931619e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 9.144e-09 4.736e-09
25- 50 1.347e-08 7.825e-09
50-150 1.993e-08 1.244e-08
15-150 4.255e-08 2.008e-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: 2.01088 ( -0.220264 0.234422 )
Norm@50keV : 2.88590E-03 ( -0.000449007 0.000436878 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 66.44 using 59 PHA bins.
# Reduced chi-squared = 1.166 for 57 degrees of freedom
# Null hypothesis probability = 1.838341e-01
Photon flux (15-150 keV) in 6.288 sec: 0.435065 ( -0.0499352 0.0499364 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.67445e-07 ( -2.39201e-08 2.46254e-08 ) ergs/cm2
Cutoff power-law model
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.83745 ( -1.08502 0.297338 )
Epeak [keV] : 37.4692 ( )
Norm@50keV : 3.66387E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 66.32 using 59 PHA bins.
# Reduced chi-squared = 1.184 for 56 degrees of freedom
# Null hypothesis probability = 1.626829e-01
Photon flux (15-150 keV) in 6.288 sec: 0.432022 ( -0.052245 0.051747 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.63734e-07 ( -2.98498e-08 2.76471e-08 ) ergs/cm2
Band function
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.113151 ( -0.857107 -0.857107 )
beta : -2.12245 ( -1.50861 0.302247 )
Epeak [keV] : 25.3515 ( -23.6392 177.473 )
Norm@50keV : 7.40466E-02 ( -0.0720582 826.762 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 65.85 using 59 PHA bins.
# Reduced chi-squared = 1.197 for 55 degrees of freedom
# Null hypothesis probability = 1.500692e-01
Photon flux (15-150 keV) in 6.288 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) = 5.06e-08
S(50-100 keV) = 5.02e-08
T90 vs. Hardness ratio plot
T90 = 5.50400000810623 sec.
Hardness ratio (energy fluence ratio) = 0.992095
Color vs. Color plot
Count Ratio (25-50 keV) / (15-25 keV) = 1.047
Count Ratio (50-100 keV) / (15-25 keV) = 0.380396
Mask shadow pattern
IMX = 1.887765493872842E-01, IMY = 2.840501912307377E-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:
-239.168000 -1.784000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
254.4538 35.3464 0.8 18.6 9.0 2.0904 14.9 0.3 Her X-1
299.5893 35.1892 1.0 51.4 -22.6 4.6493 12.0 0.7 Cyg X-1
308.2507 40.9528 4.2 54.5 -33.1 2.2215 2.8 6.4 Cyg X-3
256.2554 2.7666 2.8 45.3 48.2 2.5585 4.1 ------ UNKNOWN
171.2061 34.2756 2.5 47.6 -176.1 1.3349 4.6 ------ UNKNOWN
160.3497 28.9759 2.9 58.2 -175.5 3.7831 4.0 ------ UNKNOWN
195.0214 52.5157 2.3 26.7 -152.8 0.8067 5.1 ------ UNKNOWN
188.9274 55.4063 2.7 30.5 -147.6 0.7619 4.3 ------ UNKNOWN
305.4118 28.7584 2.1 59.0 -19.3 5.2727 5.5 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image:
-1.784000 4.504000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
254.3138 35.4530 3.7 18.4 8.9 0.0661 3.1 9.7 Her X-1
299.4845 35.2180 6.3 51.3 -22.6 -0.1031 -1.8 5.3 Cyg X-1
308.1996 41.1535 8.4 54.3 -33.3 -0.1499 -1.4 12.7 Cyg X-3
254.2184 55.2942 0.8 18.8 -56.4 0.3240 13.6 ------ UNKNOWN
163.2712 39.1204 2.6 50.9 -166.4 0.2248 4.4 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image:
59.532590 902.871500
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
254.4463 35.3370 0.7 19.9 70.9 7.3068 16.8 0.6 Her X-1
288.8049 10.9485 1.9 51.9 26.3 11.3884 6.1 0.4 GRS 1915+105
299.5662 35.1868 0.4 36.8 -4.7 14.9707 26.6 1.5 Cyg X-1
307.9815 40.8713 21.4 37.6 -19.1 -0.2727 -0.5 7.6 Cyg X-3
326.2169 38.3678 8.1 49.6 -30.3 1.2408 1.4 3.5 Cyg X-2
192.3642 30.7666 3.3 49.4 158.2 4.7117 3.5 ------ UNKNOWN
193.6580 40.5401 2.6 41.7 166.8 3.1219 4.5 ------ UNKNOWN
296.0356 29.7430 2.3 39.1 4.7 2.8137 5.1 ------ UNKNOWN
308.0455 37.6301 0.8 39.8 -15.3 8.3946 14.9 ------ UNKNOWN
160.4621 41.7713 4.2 58.7 -169.2 8.1747 2.8 ------ UNKNOWN
Plot creation:
Sun May 31 10:13:03 EDT 2015