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
297.4908 46.3553 0.0056 42.9199 20.8052 11.9637806 34.827 TRIG_00175942
Foreground time interval of the image:
-21.048 15.317 (delta_t = 36.365 [sec])
Background time interval of the image:
-27.483 -21.048 (delta_t = 6.435 [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 -21.048 sec. to 66.540 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.06218 ( -0.0316875 0.0315247 )
Norm@50keV : 1.95825E-02 ( -0.000349956 0.000348495 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 37.30 using 59 PHA bins.
# Reduced chi-squared = 0.6544 for 57 degrees of freedom
# Null hypothesis probability = 9.798102e-01
Photon flux (15-150 keV) in 87.59 sec: 2.26385 ( -0.042938 0.0431194 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.81556e-05 ( -3.007e-07 3.0081e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -21.048 sec. to 66.540 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.05657 ( -0.032354 0.0313775 )
Epeak [keV] : 9999.36 ( -9999.36 -9999.36 )
Norm@50keV : 1.96906E-02 ( -0.000330926 0.00188551 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 37.34 using 59 PHA bins.
# Reduced chi-squared = 0.6669 for 56 degrees of freedom
# Null hypothesis probability = 9.740240e-01
Photon flux (15-150 keV) in 87.59 sec: 2.26360 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 1.81608e-05 ( -2.9912e-07 3.0131e-07 ) ergs/cm2
Band function
Time interval is from -21.048 sec. to 66.540 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -9.46757E-02 ( 0.850922 0.850922 )
beta : -1.07073 ( -0.0315236 0.0316885 )
Epeak [keV] : 54.1719 ( -54.1346 212.663 )
Norm@50keV : 9.27009E-02 ( -0.0933352 730147 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 36.21 using 59 PHA bins.
# Reduced chi-squared = 0.6584 for 55 degrees of freedom
# Null hypothesis probability = 9.763475e-01
Photon flux (15-150 keV) in 87.59 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] : 24.7417 ( )
R^2/D10^2 : 5.40107E-02 ( )
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 680.26 using 59 PHA bins.
# Reduced chi-squared = 11.934 for 57 degrees of freedom
# Null hypothesis probability = 1.515975e-107
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 5.058e-07 1.857e-08
25- 50 2.855e-06 7.620e-08
50-150 1.298e-05 2.890e-07
15-150 1.634e-05 3.022e-07
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 199.363 ( )
Norm : 10.0821 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 851.05 using 59 PHA bins.
# Reduced chi-squared = 14.931 for 57 degrees of freedom
# Null hypothesis probability = 5.784507e-142
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.199e-06 4.248e-08
25- 50 4.230e-06 8.014e-08
50-150 9.278e-06 1.752e-07
15-150 1.571e-05 2.978e-07
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 8.96322 (-0.639568 0.685385)
R1^2/D10^2 : 0.790041 (-0.164963 0.218446)
kT2 [keV] : 39.4713 (-2.55049 3.14237)
R2^2/D10^2 : 1.10446E-02 (-0.00229058 0.0025498)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 36.36 using 59 PHA bins.
# Reduced chi-squared = 0.6611 for 55 degrees of freedom
# Null hypothesis probability = 9.752823e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.276e-06 8.803e-08
25- 50 3.615e-06 1.340e-07
50-150 1.340e-05 3.635e-07
15-150 1.829e-05 4.993e-07
Peak spectrum fit
Power-law model
Time interval is from 30.416 sec. to 31.416 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.902569 ( -0.084061 0.0829502 )
Norm@50keV : 6.34001E-02 ( -0.00309872 0.00308937 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 65.09 using 59 PHA bins.
# Reduced chi-squared = 1.142 for 57 degrees of freedom
# Null hypothesis probability = 2.159046e-01
Photon flux (15-150 keV) in 1 sec: 7.27703 ( -0.356349 0.356776 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.1081e-07 ( -3.65337e-08 3.66087e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 30.416 sec. to 31.416 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.681830 ( -0.340988 0.19535 )
Epeak [keV] : 359.678 ( -359.689 -359.689 )
Norm@50keV : 7.88115E-02 ( -0.0178765 0.0301428 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 63.69 using 59 PHA bins.
# Reduced chi-squared = 1.137 for 56 degrees of freedom
# Null hypothesis probability = 2.241186e-01
Photon flux (15-150 keV) in 1 sec: 7.22458 ( -0.36387 0.3641 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.06768e-07 ( -3.7579e-08 3.7433e-08 ) ergs/cm2
Band function
Time interval is from 30.416 sec. to 31.416 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 4.99998 ( -4.99998 -4.99998 )
beta : -0.934831 ( -0.0894287 0.0893581 )
Epeak [keV] : 26.6266 ( -26.6266 5.36745 )
Norm@50keV : 2723.30 ( -128.682 7.33351e+06 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 63.15 using 59 PHA bins.
# Reduced chi-squared = 1.148 for 55 degrees of freedom
# Null hypothesis probability = 2.105331e-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] : 24.3845 ( )
R^2/D10^2 : 0.196306 ( )
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 128.19 using 59 PHA bins.
# Reduced chi-squared = 2.2489 for 57 degrees of freedom
# Null hypothesis probability = 2.129692e-07
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.054e-08 2.010e-09
25- 50 1.151e-07 8.800e-09
50-150 5.089e-07 3.650e-08
15-150 6.445e-07 3.855e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 199.363 ( )
Norm : 29.0047 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 225.59 using 59 PHA bins.
# Reduced chi-squared = 3.9577 for 57 degrees of freedom
# Null hypothesis probability = 6.500153e-22
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 7.222e-08 3.880e-09
25- 50 1.389e-07 7.600e-09
50-150 3.047e-07 4.470e-08
15-150 5.159e-07 3.370e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 8.89645 (-1.98429 2.43278)
R1^2/D10^2 : 2.16454 (-1.05025 2.54934)
kT2 [keV] : 37.7854 (-6.03048 11.5394)
R2^2/D10^2 : 4.54457E-02 (-0.0248162 0.0272084)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 63.46 using 59 PHA bins.
# Reduced chi-squared = 1.154 for 55 degrees of freedom
# Null hypothesis probability = 2.027781e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 4.187e-08 1.021e-08
25- 50 1.276e-07 2.401e-08
50-150 5.452e-07 1.109e-07
15-150 7.147e-07 1.232e-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: 0.961186 ( -0.0430026 0.0426608 )
Norm@50keV : 2.28154E-02 ( -0.000551798 0.000549727 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 31.22 using 59 PHA bins.
# Reduced chi-squared = 0.5478 for 57 degrees of freedom
# Null hypothesis probability = 9.978530e-01
Photon flux (15-150 keV) in 36.36 sec: 2.62224 ( -0.0648676 0.0650663 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.09724e-06 ( -2.07832e-07 2.07926e-07 ) ergs/cm2
Cutoff power-law model
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.957206 ( -0.0455187 0.0410945 )
Epeak [keV] : 9999.36 ( -9999.36 -9999.36 )
Norm@50keV : 2.29537E-02 ( -0.000515153 0.00220839 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 31.34 using 59 PHA bins.
# Reduced chi-squared = 0.5597 for 56 degrees of freedom
# Null hypothesis probability = 9.968782e-01
Photon flux (15-150 keV) in 36.36 sec: 2.62108 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 9.09774e-06 ( -2.06525e-07 2.09615e-07 ) ergs/cm2
Band function
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.497174 ( 0.792182 0.792182 )
beta : -0.966432 ( -0.0426585 0.0430068 )
Epeak [keV] : 89.1927 ( -88.7285 338.919 )
Norm@50keV : 4.81207E-02 ( -0.0264261 0.437014 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 30.98 using 59 PHA bins.
# Reduced chi-squared = 0.5633 for 55 degrees of freedom
# Null hypothesis probability = 9.963312e-01
Photon flux (15-150 keV) in 36.36 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) = 3.50e-06
S(50-100 keV) = 6.71e-06
T90 vs. Hardness ratio plot
T90 = 54.3760000169277 sec.
Hardness ratio (energy fluence ratio) = 1.91714
Color vs. Color plot
Count Ratio (25-50 keV) / (15-25 keV) = 1.85726
Count Ratio (50-100 keV) / (15-25 keV) = 2.07579
Mask shadow pattern
IMX = 8.692680592359927E-01, IMY = -3.302945234494673E-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:
-27.483400 -21.048000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
288.8145 10.9732 3.0 37.8 -35.9 0.1359 3.8 1.9 GRS 1915+105
299.6374 35.1920 1.5 34.4 8.8 0.2470 7.9 2.4 Cyg X-1
308.1896 40.7799 0.0 33.7 24.4 -0.0637 -1.9 11.0 Cyg X-3
326.1115 38.3725 52.5 26.7 48.9 0.0066 0.2 4.2 Cyg X-2
334.4990 47.3408 2.6 36.2 59.3 0.2560 4.5 ------ UNKNOWN
14.5090 -4.7581 2.8 49.7 157.7 0.3147 4.1 ------ UNKNOWN
276.3041 39.5650 2.5 52.9 2.4 0.3543 4.6 ------ UNKNOWN
307.9951 27.6616 2.4 24.2 5.3 0.1211 4.9 ------ UNKNOWN
352.6488 -28.2649 2.8 46.8 -159.9 0.1854 4.1 ------ UNKNOWN
316.8707 -13.1302 2.6 26.9 -105.8 0.1377 4.4 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image:
-21.048000 15.316620
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
288.7627 10.9694 1547.7 37.8 -35.9 -0.0017 -0.0 2.5 GRS 1915+105
299.8137 35.2521 7.4 34.3 9.1 -0.3358 -1.5 11.4 Cyg X-1
307.9616 41.0473 62.0 34.0 24.5 -0.0455 -0.2 8.8 Cyg X-3
326.1975 38.1318 0.0 26.5 49.1 -0.0859 -0.4 11.5 Cyg X-2
330.5127 48.4691 2.3 36.9 54.6 1.9190 5.0 ------ UNKNOWN
297.4908 46.3553 0.3 42.9 20.8 11.9638 34.8 ------ UNKNOWN
300.4955 38.2015 2.1 35.8 13.7 1.2333 5.5 ------ UNKNOWN
339.4576 -20.1625 2.1 34.0 -149.5 0.9876 5.4 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image:
76.716590 302.672800
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
254.4487 35.2769 7.1 33.9 -14.6 0.3417 1.6 4.0 Her X-1
288.7847 10.9430 1.7 36.2 -86.7 3.1661 7.0 0.8 GRS 1915+105
299.5954 35.2005 0.2 11.3 -110.1 8.5628 51.8 0.3 Cyg X-1
308.0772 40.9720 1.4 9.4 -159.9 1.3565 8.3 1.9 Cyg X-3
326.0841 38.4460 3.2 22.4 179.2 0.5818 3.6 8.5 Cyg X-2
261.9401 52.3445 2.2 23.6 16.5 0.9282 5.1 ------ UNKNOWN
352.4429 24.0744 1.9 48.9 176.2 2.3139 6.0 ------ UNKNOWN
297.3729 46.3538 2.3 0.1 -23.4 0.8229 4.9 ------ UNKNOWN
265.2287 34.5538 2.5 27.0 -25.6 0.7697 4.7 ------ UNKNOWN
230.3134 23.0171 2.6 58.0 -10.4 4.2701 4.5 ------ UNKNOWN
Plot creation:
Sun May 31 14:47:12 EDT 2015