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
357.2237 36.0996 0.0042 41.1652 -130.2012 7.0458895 45.150 TRIG_00559482
Foreground time interval of the image:
-1.140 5.352 (delta_t = 6.492 [sec])
Background time interval of the image:
-239.368 -1.140 (delta_t = 238.228 [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)
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 -1.140 sec. to 5.352 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.57870 ( -0.0453813 0.0454658 )
Norm@50keV : 7.39963E-02 ( -0.00197593 0.00197582 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 76.37 using 59 PHA bins.
# Reduced chi-squared = 1.340 for 57 degrees of freedom
# Null hypothesis probability = 4.432090e-02
Photon flux (15-150 keV) in 6.492 sec: 9.44722 ( -0.278662 0.279287 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.50469e-06 ( -1.24172e-07 1.24243e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -1.140 sec. to 5.352 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.902600 ( -0.210102 0.200911 )
Epeak [keV] : 89.1621 ( -9.35095 15.3628 )
Norm@50keV : 0.152299 ( -0.0287344 0.0372383 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 40.05 using 59 PHA bins.
# Reduced chi-squared = 0.7152 for 56 degrees of freedom
# Null hypothesis probability = 9.468694e-01
Photon flux (15-150 keV) in 6.492 sec: 9.09109 ( -0.29281 0.2939 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.3778e-06 ( -1.31807e-07 1.3119e-07 ) ergs/cm2
Band function
Time interval is from -1.140 sec. to 5.352 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.583242 ( -0.421022 0.636107 )
beta : -1.96166 ( 1.96158 0.169203 )
Epeak [keV] : 69.8488 ( -16.8225 25.71 )
Norm@50keV : 0.231216 ( -0.0941347 0.331924 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 37.99 using 59 PHA bins.
# Reduced chi-squared = 0.6907 for 55 degrees of freedom
# Null hypothesis probability = 9.610036e-01
Photon flux (15-150 keV) in 6.492 sec: 9.00890 ( -2.0089 -0.30416 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.36349e-06 ( -4.36345e-06 -1.30139e-07 ) ergs/cm2
Single BB
Spectral model blackbody:
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 16.0804 ( )
R^2/D10^2 : 0.833057 ( )
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 262.94 using 59 PHA bins.
# Reduced chi-squared = 4.6130 for 57 degrees of freedom
# Null hypothesis probability = 3.262601e-28
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.888e-07 1.522e-08
25- 50 1.221e-06 4.447e-08
50-150 2.210e-06 1.016e-07
15-150 3.720e-06 1.097e-07
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 197.888 (-24.9611 -197.914)
Norm : 38.4830 (-1.04732 1.17833)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 48.83 using 59 PHA bins.
# Reduced chi-squared = 0.8567 for 57 degrees of freedom
# Null hypothesis probability = 7.708097e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 6.227e-07 2.454e-08
25- 50 1.197e-06 4.025e-08
50-150 2.618e-06 9.154e-08
15-150 4.438e-06 1.519e-07
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 8.42879 (-0.9396 0.98002)
R1^2/D10^2 : 4.90761 (-1.35377 2.15575)
kT2 [keV] : 26.6788 (-2.70055 3.75559)
R2^2/D10^2 : 9.89349E-02 (-0.0401231 0.0539097)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 43.07 using 59 PHA bins.
# Reduced chi-squared = 0.7831 for 55 degrees of freedom
# Null hypothesis probability = 8.784046e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 5.010e-07 4.489e-08
25- 50 1.260e-06 8.018e-08
50-150 2.593e-06 2.428e-07
15-150 4.354e-06 3.291e-07
Peak spectrum fit
Power-law model
Time interval is from 0.060 sec. to 1.060 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.26808 ( -0.0672229 0.0671409 )
Norm@50keV : 0.144177 ( -0.0059853 0.00598526 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 72.19 using 59 PHA bins.
# Reduced chi-squared = 1.267 for 57 degrees of freedom
# Null hypothesis probability = 8.465227e-02
Photon flux (15-150 keV) in 1 sec: 17.1037 ( -0.73851 0.739194 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.43616e-06 ( -6.41931e-08 6.42809e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.060 sec. to 1.060 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.655967 ( -0.30053 0.281713 )
Epeak [keV] : 122.632 ( -23.3174 55.8742 )
Norm@50keV : 0.277369 ( -0.070439 0.101206 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.45 using 59 PHA bins.
# Reduced chi-squared = 1.026 for 56 degrees of freedom
# Null hypothesis probability = 4.213166e-01
Photon flux (15-150 keV) in 1 sec: 16.7967 ( -0.7505 0.7512 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.41045e-06 ( 0 0 ) ergs/cm2
Band function
Time interval is from 0.060 sec. to 1.060 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.458735 ( -0.533261 2.22811 )
beta : -1.66826 ( 1.66826 0.277916 )
Epeak [keV] : 97.3274 ( -55.3937 51.302 )
Norm@50keV : 0.359460 ( -0.148759 12.7777 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.16 using 59 PHA bins.
# Reduced chi-squared = 1.039 for 55 degrees of freedom
# Null hypothesis probability = 3.947120e-01
Photon flux (15-150 keV) in 1 sec: 16.7202 ( -9.7202 -0.7598 ) 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] : 18.5633 ( )
R^2/D10^2 : 1.02937 ( )
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 145.50 using 59 PHA bins.
# Reduced chi-squared = 2.5527 for 57 degrees of freedom
# Null hypothesis probability = 1.115473e-09
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 7.030e-08 5.975e-09
25- 50 3.326e-07 1.925e-08
50-150 8.381e-07 5.440e-08
15-150 1.241e-06 6.000e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 199.361 ( )
Norm : 71.6183 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 115.01 using 59 PHA bins.
# Reduced chi-squared = 2.0178 for 57 degrees of freedom
# Null hypothesis probability = 8.504756e-06
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.783e-07 7.900e-09
25- 50 3.431e-07 1.500e-08
50-150 7.524e-07 3.390e-08
15-150 1.274e-06 5.850e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 8.65832 (-1.55284 1.77073)
R1^2/D10^2 : 6.93088 (-2.74868 5.52903)
kT2 [keV] : 29.4374 (-4.00435 6.7664)
R2^2/D10^2 : 0.171129 (-0.0904473 0.125979)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.26 using 59 PHA bins.
# Reduced chi-squared = 1.041 for 55 degrees of freedom
# Null hypothesis probability = 3.913407e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.225e-07 2.291e-08
25- 50 3.415e-07 4.095e-08
50-150 9.525e-07 1.732e-07
15-150 1.417e-06 1.930e-07
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: 1.57870 ( -0.0453813 0.0454658 )
Norm@50keV : 7.39963E-02 ( -0.00197593 0.00197582 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 76.37 using 59 PHA bins.
# Reduced chi-squared = 1.340 for 57 degrees of freedom
# Null hypothesis probability = 4.432090e-02
Photon flux (15-150 keV) in 6.492 sec: 9.44722 ( -0.278662 0.279287 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.50469e-06 ( -1.24172e-07 1.24243e-07 ) ergs/cm2
Cutoff power-law model
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.902600 ( -0.210102 0.200911 )
Epeak [keV] : 89.1621 ( -9.35095 15.3628 )
Norm@50keV : 0.152299 ( -0.0287344 0.0372383 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 40.05 using 59 PHA bins.
# Reduced chi-squared = 0.7152 for 56 degrees of freedom
# Null hypothesis probability = 9.468694e-01
Photon flux (15-150 keV) in 6.492 sec: 9.09109 ( -0.29281 0.2939 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.3778e-06 ( -1.31807e-07 1.3119e-07 ) ergs/cm2
Band function
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.583242 ( -0.421022 0.636107 )
beta : -1.96166 ( 1.96158 0.169203 )
Epeak [keV] : 69.8488 ( -16.8225 25.71 )
Norm@50keV : 0.231216 ( -0.0941347 0.331924 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 37.99 using 59 PHA bins.
# Reduced chi-squared = 0.6907 for 55 degrees of freedom
# Null hypothesis probability = 9.610036e-01
Photon flux (15-150 keV) in 6.492 sec: 9.00890 ( -2.0089 -0.30416 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.36349e-06 ( -4.36345e-06 -1.30139e-07 ) ergs/cm2
S(25-50 keV) vs. S(50-100 keV) plot
S(25-50 keV) = 1.16e-06
S(50-100 keV) = 1.55e-06
T90 vs. Hardness ratio plot
T90 = 4.37999993562698 sec.
Hardness ratio (energy fluence ratio) = 1.33621
Color vs. Color plot
Count Ratio (25-50 keV) / (15-25 keV) = 1.63915
Count Ratio (50-100 keV) / (15-25 keV) = 1.27673
Mask shadow pattern
IMX = -5.643777236738406E-01, IMY = 6.678219948756898E-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:
-239.368000 -1.140000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
299.7182 35.2290 11.9 48.0 162.7 0.6311 1.0 6.5 Cyg X-1
307.9691 40.9329 5.0 47.4 174.4 1.1179 2.3 6.5 Cyg X-3
326.1664 38.3472 6.9 38.8 -168.9 0.4665 1.7 1.6 Cyg X-2
293.5343 6.7438 2.1 42.0 122.0 4.7854 5.6 ------ UNKNOWN
324.4688 -49.8433 4.3 51.1 31.2 3.0710 2.7 ------ UNKNOWN
339.6856 -21.8095 2.8 22.6 11.3 0.8404 4.1 ------ UNKNOWN
19.3854 -41.2326 3.1 57.7 -16.0 3.7922 3.7 ------ UNKNOWN
9.2759 -15.3222 2.5 37.2 -41.2 1.3562 4.5 ------ UNKNOWN
23.2843 -17.4297 3.8 50.6 -44.5 3.6390 3.0 ------ UNKNOWN
0.2045 46.3895 2.7 51.0 -135.6 4.8233 4.2 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image:
-1.140000 5.352000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
299.6031 35.1971 13.9 48.0 162.6 0.1176 0.8 0.7 Cyg X-1
308.1539 40.7937 5.7 47.2 174.4 0.2269 2.0 9.7 Cyg X-3
326.1232 38.1434 0.0 38.6 -169.1 -0.0132 -0.2 10.9 Cyg X-2
357.2237 36.0996 0.3 41.2 -130.2 7.0462 45.2 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image:
74.332600 962.694400
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
299.4395 35.2120 5.2 46.2 133.2 -1.5205 -2.2 7.4 Cyg X-1
308.1175 40.9567 18.5 38.2 139.1 0.2034 0.6 0.4 Cyg X-3
326.1761 38.3155 129.5 24.7 130.9 0.0157 0.1 0.4 Cyg X-2
311.6410 23.9793 2.5 40.9 112.1 2.6542 4.6 ------ UNKNOWN
301.7816 76.1833 2.2 47.0 -169.2 1.3482 5.3 ------ UNKNOWN
200.2582 84.0522 3.3 59.4 -156.3 3.2461 3.5 ------ UNKNOWN
109.6091 85.3252 2.5 55.8 -148.4 4.0181 4.5 ------ UNKNOWN
49.4744 38.7159 3.2 41.0 -83.6 2.3148 3.6 ------ UNKNOWN
Plot creation:
Sat May 30 16:12:06 EDT 2015