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
273.9026 69.2481 0.0049 15.3125 -119.7098 4.4756009 39.376 TRIG_00518626
Foreground time interval of the image:
-68.984 10.989 (delta_t = 79.973 [sec])
Background time interval of the image:
-239.312 -68.984 (delta_t = 170.328 [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 0.512000
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 0.512000
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 0.512000
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 -68.984 sec. to 21.592 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.98561 ( -0.0697645 0.070626 )
Norm@50keV : 3.19970E-03 ( -0.000125535 0.000124808 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 62.18 using 59 PHA bins.
# Reduced chi-squared = 1.091 for 57 degrees of freedom
# Null hypothesis probability = 2.970657e-01
Photon flux (15-150 keV) in 90.58 sec: 0.476807 ( -0.0177482 0.0178074 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.67086e-06 ( -1.0052e-07 1.00954e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -68.984 sec. to 21.592 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.39955 ( -0.32662 0.30226 )
Epeak [keV] : 46.8378 ( -6.55892 7.89511 )
Norm@50keV : 6.52742E-03 ( -0.00197347 0.00314675 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 50.46 using 59 PHA bins.
# Reduced chi-squared = 0.9011 for 56 degrees of freedom
# Null hypothesis probability = 6.837655e-01
Photon flux (15-150 keV) in 90.58 sec: 0.456676 ( -0.02016 0.02026 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.51775e-06 ( -1.24267e-07 1.25317e-07 ) ergs/cm2
Band function
Time interval is from -68.984 sec. to 21.592 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.11451 ( -0.51673 1.28177 )
beta : -2.33312 ( 2.33406 0.241043 )
Epeak [keV] : 42.2125 ( -9.47458 10.1563 )
Norm@50keV : 9.80060E-03 ( -0.00437617 0.0656097 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 49.36 using 59 PHA bins.
# Reduced chi-squared = 0.8975 for 55 degrees of freedom
# Null hypothesis probability = 6.889269e-01
Photon flux (15-150 keV) in 90.58 sec: 0.454146 ( 6.54585 -0.020517 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.53109e-06 ( -2.53045e-06 -1.20009e-07 ) ergs/cm2
Single BB
Spectral model blackbody:
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 11.2195 ( )
R^2/D10^2 : 0.134929 ( )
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 175.02 using 59 PHA bins.
# Reduced chi-squared = 3.0705 for 57 degrees of freedom
# Null hypothesis probability = 6.360007e-14
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 3.226e-07 2.265e-08
25- 50 9.355e-07 3.569e-08
50-150 6.752e-07 5.842e-08
15-150 1.933e-06 7.337e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 73.8697 (-8.23809 9.94465)
Norm : 2.24153 (-0.137569 0.149264)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 50.57 using 59 PHA bins.
# Reduced chi-squared = 0.8871 for 57 degrees of freedom
# Null hypothesis probability = 7.135843e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 5.237e-07 2.722e-08
25- 50 8.450e-07 2.849e-08
50-150 1.129e-06 8.922e-08
15-150 2.497e-06 1.051e-07
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 6.58713 (-0.903981 0.913715)
R1^2/D10^2 : 0.710655 (-0.248161 0.481728)
kT2 [keV] : 20.4282 (-2.95308 4.30747)
R2^2/D10^2 : 9.39745E-03 (-0.00507611 0.0088992)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.66 using 59 PHA bins.
# Reduced chi-squared = 0.9938 for 55 degrees of freedom
# Null hypothesis probability = 4.877038e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 4.873e-07 6.386e-08
25- 50 8.520e-07 8.274e-08
50-150 1.131e-06 2.341e-07
15-150 2.470e-06 3.139e-07
Peak spectrum fit
Power-law model
Time interval is from 3.588 sec. to 4.588 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.85429 ( -0.080727 0.0818493 )
Norm@50keV : 3.36734E-02 ( -0.00164454 0.00163443 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 62.26 using 59 PHA bins.
# Reduced chi-squared = 1.092 for 57 degrees of freedom
# Null hypothesis probability = 2.944009e-01
Photon flux (15-150 keV) in 1 sec: 4.74142 ( -0.217802 0.218136 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.09604e-07 ( -1.51578e-08 1.52315e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 3.588 sec. to 4.588 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.23365 ( -0.3961 0.359522 )
Epeak [keV] : 56.4725 ( -7.85908 18.2034 )
Norm@50keV : 7.25233E-02 ( -0.025607 0.0454762 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 53.04 using 59 PHA bins.
# Reduced chi-squared = 0.9471 for 56 degrees of freedom
# Null hypothesis probability = 5.877485e-01
Photon flux (15-150 keV) in 1 sec: 4.58973 ( -0.23346 0.23358 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.92916e-07 ( -1.7841e-08 1.7909e-08 ) ergs/cm2
Band function
Time interval is from 3.588 sec. to 4.588 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.184424 ( -1.04531 1.67263 )
beta : -2.15055 ( -0.390817 0.181622 )
Epeak [keV] : 39.3359 ( -8.66524 15.5515 )
Norm@50keV : 0.349492 ( -0.328891 5.24002 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 48.07 using 59 PHA bins.
# Reduced chi-squared = 0.8739 for 55 degrees of freedom
# Null hypothesis probability = 7.346329e-01
Photon flux (15-150 keV) in 1 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 2.95293e-07 ( -2.95286e-07 -1.6833e-08 ) ergs/cm2
Single BB
Spectral model blackbody:
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 11.5613 ( )
R^2/D10^2 : 1.27929 ( )
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 130.01 using 59 PHA bins.
# Reduced chi-squared = 2.2809 for 57 degrees of freedom
# Null hypothesis probability = 1.249342e-07
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 3.602e-08 2.970e-09
25- 50 1.084e-07 5.000e-09
50-150 8.493e-08 8.595e-09
15-150 2.294e-07 1.220e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 90.8192 (-13.3529 17.3523)
Norm : 21.3343 (-1.43852 1.57413)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 52.87 using 59 PHA bins.
# Reduced chi-squared = 0.9276 for 57 degrees of freedom
# Null hypothesis probability = 6.305754e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 5.568e-08 4.355e-09
25- 50 9.436e-08 4.240e-09
50-150 1.445e-07 4.080e-08
15-150 2.945e-07 3.925e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 8.08735 (-1.1609 1.05171)
R1^2/D10^2 : 3.76696 (-1.18717 2.26704)
kT2 [keV] : 28.6936 (-7.39681 15.5428)
R2^2/D10^2 : 2.63537E-02 (-0.0198053 0.0555824)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 51.90 using 59 PHA bins.
# Reduced chi-squared = 0.9437 for 55 degrees of freedom
# Null hypothesis probability = 5.937780e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 4.840e-08 5.405e-09
25- 50 1.012e-07 1.095e-08
50-150 1.465e-07 5.278e-08
15-150 2.962e-07 6.185e-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: 1.95409 ( -0.0707982 0.0716684 )
Norm@50keV : 3.30863E-03 ( -0.000132706 0.000131952 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 61.99 using 59 PHA bins.
# Reduced chi-squared = 1.087 for 57 degrees of freedom
# Null hypothesis probability = 3.029146e-01
Photon flux (15-150 keV) in 79.97 sec: 0.486106 ( -0.0184831 0.0185381 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.43526e-06 ( -9.47413e-08 9.51851e-08 ) ergs/cm2
Cutoff power-law model
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.32980 ( -0.334276 0.308976 )
Epeak [keV] : 49.2022 ( -6.07484 8.58218 )
Norm@50keV : 7.06764E-03 ( -0.0021758 0.00350343 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 49.17 using 59 PHA bins.
# Reduced chi-squared = 0.8780 for 56 degrees of freedom
# Null hypothesis probability = 7.290364e-01
Photon flux (15-150 keV) in 79.97 sec: 0.464928 ( -0.020841 0.020935 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.28862e-06 ( -1.15901e-07 1.16948e-07 ) ergs/cm2
Band function
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.02035 ( -0.557988 1.21305 )
beta : -2.31044 ( 2.31222 0.237398 )
Epeak [keV] : 43.3907 ( -9.56413 12.0407 )
Norm@50keV : 1.10222E-02 ( -0.00586837 0.0632619 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 48.17 using 59 PHA bins.
# Reduced chi-squared = 0.8759 for 55 degrees of freedom
# Null hypothesis probability = 7.309009e-01
Photon flux (15-150 keV) in 79.97 sec: 0.462408 ( 6.53759 -0.021194 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.30338e-06 ( -2.30282e-06 -1.11606e-07 ) ergs/cm2
S(25-50 keV) vs. S(50-100 keV) plot
S(25-50 keV) = 8.01e-07
S(50-100 keV) = 8.09e-07
T90 vs. Hardness ratio plot
T90 = 69.4799999594688 sec.
Hardness ratio (energy fluence ratio) = 1.00999
Color vs. Color plot
Count Ratio (25-50 keV) / (15-25 keV) = 1.08938
Count Ratio (50-100 keV) / (15-25 keV) = 0.560942
Mask shadow pattern
IMX = -1.356994435304406E-01, IMY = 2.378115082158468E-01
TIME vs. PHA plot around the trigger time
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 0.512000
TIME vs. DetID plot around the trigger time
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 0.512000
100 us light curve (15-350 keV)
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 0.512000
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:
-239.312000 -68.984000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
254.4553 35.3400 382.6 22.3 21.9 0.0040 0.0 0.2 Her X-1
288.8122 10.9436 2.8 54.8 -18.2 1.8672 4.1 0.8 GRS 1915+105
299.6056 35.2256 2.2 39.0 -47.4 1.2705 5.3 1.6 Cyg X-1
308.0811 41.0057 2.4 39.2 -61.4 1.4859 4.8 3.4 Cyg X-3
246.2489 9.9980 2.5 47.7 35.6 2.1826 4.7 ------ UNKNOWN
148.5366 52.0614 3.4 53.6 160.8 2.4999 3.4 ------ UNKNOWN
193.0777 59.1035 2.6 29.6 147.0 0.7651 4.4 ------ UNKNOWN
104.6735 62.2107 2.8 57.4 -168.8 2.7539 4.2 ------ UNKNOWN
291.5502 55.9962 2.3 21.9 -74.2 0.7666 5.0 ------ UNKNOWN
319.5258 52.9212 3.1 37.6 -84.2 1.4525 3.7 ------ UNKNOWN
19.6637 69.0950 2.3 48.0 -128.9 2.9132 5.0 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image:
-68.984000 10.988590
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
254.5056 35.4389 6.0 22.2 21.8 0.2131 1.9 6.2 Her X-1
288.6898 10.7723 14.9 54.9 -18.0 0.2678 0.8 12.2 GRS 1915+105
299.4284 35.0696 66.4 39.0 -47.0 0.0314 0.2 11.2 Cyg X-1
308.0573 40.9406 3.8 39.3 -61.3 0.7449 3.0 2.5 Cyg X-3
273.9026 69.2481 0.3 15.3 -119.7 4.4755 39.4 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image:
48.388600 332.788590
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
254.2715 35.3647 4.8 35.6 30.4 -0.6678 -2.4 9.2 Her X-1
288.7528 10.9315 4.2 59.1 -14.7 2.9814 2.7 2.8 GRS 1915+105
299.6108 35.1874 1.5 36.9 -33.8 2.2537 7.9 1.3 Cyg X-1
308.0602 40.9595 1.4 33.5 -47.9 2.3974 8.3 2.3 Cyg X-3
326.2774 38.3106 13.9 41.5 -67.4 0.6895 0.8 5.0 Cyg X-2
161.0203 57.5847 2.5 44.3 137.4 3.3465 4.5 ------ UNKNOWN
256.3599 27.0794 2.8 43.4 25.3 1.6972 4.2 ------ UNKNOWN
290.8042 43.4501 2.5 27.3 -25.1 0.9504 4.6 ------ UNKNOWN
10.4969 77.8488 3.3 25.1 -148.1 0.6904 3.5 ------ UNKNOWN
Plot creation:
Sat May 30 19:56:10 EDT 2015