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
333.5699 -26.6012 0.0165 46.0716 20.2673 0.9025207 11.569 TRIG_00351588
Foreground time interval of the image:
-0.128 6.224 (delta_t = 6.352 [sec])
Background time interval of the image:
-212.715 -0.128 (delta_t = 212.587 [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 0.256000
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 0.256000
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 0.256000
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 -0.128 sec. to 6.224 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.04914 ( -0.514194 0.635132 )
Norm@50keV : 1.74053E-03 ( -0.000760864 0.000771407 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.53 using 59 PHA bins.
# Reduced chi-squared = 1.009 for 57 degrees of freedom
# Null hypothesis probability = 4.556077e-01
Photon flux (15-150 keV) in 6.352 sec: 0.267035 ( -0.0964 0.0963613 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.03045e-07 ( -4.09559e-08 4.44775e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.128 sec. to 6.224 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -3.85276 ( )
Epeak [keV] : 38.2391 ( -7.87159 11.333 )
Norm@50keV : 5.54975 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 50.62 using 59 PHA bins.
# Reduced chi-squared = 0.9040 for 56 degrees of freedom
# Null hypothesis probability = 6.777999e-01
Photon flux (15-150 keV) in 6.352 sec: 0.252729 ( -0.087434 0.092031 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.7178e-08 ( -3.03405e-08 3.57338e-08 ) ergs/cm2
Band function
Time interval is from -0.128 sec. to 6.224 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 3.65339 ( -2.75179 -2.10131 )
beta : -10.0000 ( 10 1.24345e-14 )
Epeak [keV] : 38.2852 ( -9.76942 11.342 )
Norm@50keV : 4.25152 ( -4.24993 10.6448 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 50.62 using 59 PHA bins.
# Reduced chi-squared = 0.9203 for 55 degrees of freedom
# Null hypothesis probability = 6.426931e-01
Photon flux (15-150 keV) in 6.352 sec: 0.254638 ( 6.74536 -0.086365 ) 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] : 10.0225 (-2.43135 3.17937)
R^2/D10^2 : 0.146975 (-0.146975 0.274372)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 51.01 using 59 PHA bins.
# Reduced chi-squared = 0.8950 for 57 degrees of freedom
# Null hypothesis probability = 6.979252e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.911e-08 1.198e-08
25- 50 4.767e-08 2.933e-08
50-150 2.504e-08 1.899e-08
15-150 9.183e-08 5.764e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 53.7766 (-27.2159 95.818)
Norm : 1.54738 (-0.651646 1.04717)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 55.01 using 59 PHA bins.
# Reduced chi-squared = 0.9650 for 57 degrees of freedom
# Null hypothesis probability = 5.502093e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.441e-08 1.625e-08
25- 50 3.595e-08 2.743e-08
50-150 3.732e-08 5.323e-08
15-150 9.769e-08 9.804e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 0.270589 (-0.270589 -0.270589)
R1^2/D10^2 : 2.29132E-03 (-0.00229132 -0.00229132)
kT2 [keV] : 10.0228 (-2.43165 3.17907)
R2^2/D10^2 : 0.146958 (-0.0979935 0.273758)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 51.01 using 59 PHA bins.
# Reduced chi-squared = 0.9275 for 55 degrees of freedom
# Null hypothesis probability = 6.276226e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 0.000e+00 0.000e+00
25- 50 0.000e+00 0.000e+00
50-150 0.000e+00 0.000e+00
15-150 0.000e+00 0.000e+00
Peak spectrum fit
Power-law model
Time interval is from -0.316 sec. to 0.684 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.894917 ( -0.212476 0.20321 )
Norm@50keV : 3.82889E-02 ( -0.00469858 0.00464467 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 46.16 using 59 PHA bins.
# Reduced chi-squared = 0.8098 for 57 degrees of freedom
# Null hypothesis probability = 8.472341e-01
Photon flux (15-150 keV) in 1 sec: 4.39452 ( -0.536169 0.53836 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.30553e-07 ( -5.30098e-08 5.32179e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.316 sec. to 0.684 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.567904 ( -0.924107 0.426409 )
Epeak [keV] : 262.489 ( -264.472 -264.472 )
Norm@50keV : 5.26269E-02 ( -0.0182384 0.0707868 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 45.66 using 59 PHA bins.
# Reduced chi-squared = 0.8153 for 56 degrees of freedom
# Null hypothesis probability = 8.366253e-01
Photon flux (15-150 keV) in 1 sec: 4.34195 ( -0.55031 0.55207 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.26378e-07 ( -5.5346e-08 5.4661e-08 ) ergs/cm2
Band function
Time interval is from -0.316 sec. to 0.684 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 5.00000 ( -5 -5 )
beta : -0.929306 ( -0.220937 0.223798 )
Epeak [keV] : 26.5398 ( -26.5309 17.8798 )
Norm@50keV : 1672.23 ( -194.95 6.27802e+06 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 45.62 using 59 PHA bins.
# Reduced chi-squared = 0.8295 for 55 degrees of freedom
# Null hypothesis probability = 8.122859e-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] : 24.5881 (-3.7507 4.85281)
R^2/D10^2 : 0.114961 (-0.0482923 0.0770932)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.99 using 59 PHA bins.
# Reduced chi-squared = 0.9647 for 57 degrees of freedom
# Null hypothesis probability = 5.509513e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.218e-08 3.147e-09
25- 50 6.851e-08 1.406e-08
50-150 3.078e-07 6.220e-08
15-150 3.885e-07 6.990e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 200.000 (-22.7955 -200)
Norm : 17.9245 (-2.23536 2.23536)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 73.76 using 59 PHA bins.
# Reduced chi-squared = 1.294 for 57 degrees of freedom
# Null hypothesis probability = 6.690939e-02
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 4.465e-08 2.534e-08
25- 50 8.588e-08 4.730e-08
50-150 1.883e-07 1.037e-07
15-150 3.189e-07 1.763e-07
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 9.98337 (-4.28991 6.9277)
R1^2/D10^2 : 0.953953 (-0.695741 4.23978)
kT2 [keV] : 40.4581 (-13.1981 -40.482)
R2^2/D10^2 : 2.18379E-02 (-0.0209567 0.0547611)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 45.06 using 59 PHA bins.
# Reduced chi-squared = 0.8193 for 55 degrees of freedom
# Null hypothesis probability = 8.281644e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.393e-08 1.389e-08
25- 50 7.931e-08 4.205e-08
50-150 3.284e-07 1.767e-07
15-150 4.316e-07 2.243e-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: 1.06233 ( -0.273625 0.259139 )
Norm@50keV : 9.17981E-03 ( -0.00136551 0.00134233 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 52.45 using 59 PHA bins.
# Reduced chi-squared = 0.9201 for 57 degrees of freedom
# Null hypothesis probability = 6.463856e-01
Photon flux (15-150 keV) in 6.352 sec: 1.06132 ( -0.163814 0.164868 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.17162e-07 ( -9.00847e-08 9.04874e-08 ) ergs/cm2
Cutoff power-law model
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.06368 ( -0.282568 0.254467 )
Epeak [keV] : 9999.36 ( -9999.36 -9999.36 )
Norm@50keV : 9.24185E-03 ( -0.00135188 0.00832076 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 52.46 using 59 PHA bins.
# Reduced chi-squared = 0.9368 for 56 degrees of freedom
# Null hypothesis probability = 6.096321e-01
Photon flux (15-150 keV) in 6.352 sec: 1.06484 ( -0.167606 0.15797 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.15875e-07 ( -8.89629e-08 9.14834e-08 ) ergs/cm2
Band function
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.871448 ( 0.871414 0.871414 )
beta : -1.06232 ( 1.06232 0.273619 )
Epeak [keV] : 47.9319 ( -47.9713 -47.9713 )
Norm@50keV : 1.57233E-02 ( -0.00687401 0 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 52.45 using 59 PHA bins.
# Reduced chi-squared = 0.9536 for 55 degrees of freedom
# Null hypothesis probability = 5.728273e-01
Photon flux (15-150 keV) in 6.352 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) = 3.13e-08
S(50-100 keV) = 3.07e-08
T90 vs. Hardness ratio plot
T90 = 5.66399997472763 sec.
Hardness ratio (energy fluence ratio) = 0.980831
Color vs. Color plot
Count Ratio (25-50 keV) / (15-25 keV) = 1.33114
Count Ratio (50-100 keV) / (15-25 keV) = 1.66918
Mask shadow pattern
IMX = 9.738492822632381E-01, IMY = -3.596064605939755E-01
TIME vs. PHA plot around the trigger time
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 0.256000
TIME vs. DetID plot around the trigger time
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 0.256000
100 us light curve (15-350 keV)
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 0.256000
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:
-212.715400 -0.128000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
299.5797 35.1877 0.5 34.7 143.2 7.1896 23.9 1.0 Cyg X-1
308.0275 40.9324 1.9 31.2 158.2 1.4273 6.0 3.9 Cyg X-3
326.1242 38.2501 8.6 20.2 179.2 0.2327 1.3 4.8 Cyg X-2
344.0508 -18.5084 2.1 39.1 4.7 1.5026 5.6 ------ UNKNOWN
347.0993 -1.7928 2.1 24.5 -12.4 0.9835 5.4 ------ UNKNOWN
351.7921 31.3488 2.7 19.5 -112.1 0.7462 4.3 ------ UNKNOWN
18.5931 9.2361 3.0 43.6 -64.0 3.4926 3.8 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image:
-0.128000 6.224000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
299.5288 35.3447 4.1 34.7 143.5 -0.1322 -2.8 9.1 Cyg X-1
308.0613 41.0511 3.1 31.3 158.4 0.1296 3.7 6.3 Cyg X-3
326.0816 38.1283 0.0 20.1 179.0 -0.0460 -1.8 12.4 Cyg X-2
312.6863 -14.8924 2.5 40.6 52.7 0.4419 4.7 ------ UNKNOWN
333.5700 -26.6012 1.0 46.1 20.3 0.9024 11.6 ------ UNKNOWN
1.7474 76.2894 2.7 58.5 -153.8 0.6752 4.3 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image:
78.284590 962.844000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
35.8112 -41.4906 3.1 52.5 -33.3 6.1886 3.8 ------ UNKNOWN
350.0788 19.2221 2.8 48.6 -135.7 7.9176 4.2 ------ UNKNOWN
Plot creation:
Thu Aug 13 13:31:22 EDT 2015