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
13.1510 51.5705 0.0091 17.5515 -137.5648 1.6335769 21.125 TRIG_00510341
Foreground time interval of the image:
-10.048 34.797 (delta_t = 44.845 [sec])
Background time interval of the image:
-239.504 -10.048 (delta_t = 229.456 [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 4.096000
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 4.096000
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 4.096000
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 -10.048 sec. to 111.232 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.74621 ( -0.149902 0.154005 )
Norm@50keV : 1.12364E-03 ( -0.000107193 0.000105582 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.01 using 59 PHA bins.
# Reduced chi-squared = 1.035 for 57 degrees of freedom
# Null hypothesis probability = 4.018619e-01
Photon flux (15-150 keV) in 121.3 sec: 0.151723 ( -0.0124324 0.0124358 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.25794e-06 ( -1.23956e-07 1.26094e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -10.048 sec. to 111.232 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.29873 ( -0.713459 0.519462 )
Epeak [keV] : 68.2237 ( -19.2054 -68.2256 )
Norm@50keV : 2.00184E-03 ( -0.00094732 0.00299807 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.48 using 59 PHA bins.
# Reduced chi-squared = 1.026 for 56 degrees of freedom
# Null hypothesis probability = 4.200352e-01
Photon flux (15-150 keV) in 121.3 sec: 0.148536 ( -0.013176 0.01315 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.19366e-06 ( -1.48534e-07 1.52878e-07 ) ergs/cm2
Band function
Time interval is from -10.048 sec. to 111.232 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 0.828972 ( -0.815876 -0.815876 )
beta : -1.88982 ( 1.88997 0.225584 )
Epeak [keV] : 29.9738 ( -30.0947 82.0193 )
Norm@50keV : 7.72458E-02 ( -0.0706722 74.2649 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.81 using 59 PHA bins.
# Reduced chi-squared = 1.033 for 55 degrees of freedom
# Null hypothesis probability = 4.075958e-01
Photon flux (15-150 keV) in 121.3 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 1.20368e-06 ( -1.20284e-06 -1.44371e-07 ) ergs/cm2
Single BB
Spectral model blackbody:
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 11.3604 (-1.11951 1.26684)
R^2/D10^2 : 4.43159E-02 (-0.0142997 0.0207586)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 84.04 using 59 PHA bins.
# Reduced chi-squared = 1.474 for 57 degrees of freedom
# Null hypothesis probability = 1.140964e-02
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.458e-07 2.103e-08
25- 50 4.294e-07 4.039e-08
50-150 3.207e-07 6.587e-08
15-150 8.959e-07 9.316e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 106.462 (-29.912 56.2494)
Norm : 0.661206 (-0.0709718 0.0828059)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.44 using 59 PHA bins.
# Reduced chi-squared = 1.008 for 57 degrees of freedom
# Null hypothesis probability = 4.589212e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.096e-07 2.432e-08
25- 50 3.668e-07 3.700e-08
50-150 6.155e-07 2.331e-07
15-150 1.192e-06 2.521e-07
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 6.52199 (-1.88688 2.13006)
R1^2/D10^2 : 0.227601 (-0.130839 0.50161)
kT2 [keV] : 21.8359 (-6.13342 19.6063)
R2^2/D10^2 : 2.87284E-03 (-0.00252784 0.00791982)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.16 using 59 PHA bins.
# Reduced chi-squared = 1.057 for 55 degrees of freedom
# Null hypothesis probability = 3.598573e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.051e-07 6.833e-08
25- 50 3.697e-07 1.203e-07
50-150 6.049e-07 3.154e-07
15-150 1.180e-06 4.657e-07
Peak spectrum fit
Power-law model
Time interval is from -4.364 sec. to -3.364 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.74464 ( -0.351731 0.379416 )
Norm@50keV : 4.79445E-03 ( -0.00121066 0.001173 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 77.75 using 59 PHA bins.
# Reduced chi-squared = 1.364 for 57 degrees of freedom
# Null hypothesis probability = 3.525379e-02
Photon flux (15-150 keV) in 1 sec: 0.647014 ( -0.136204 0.136204 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.42539e-08 ( -1.12011e-08 1.17236e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -4.364 sec. to -3.364 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.600980 ( -5.46419 2.38139 )
Epeak [keV] : 43.2182 ( -9.27007 196.121 )
Norm@50keV : 0.120154 ( -0.141889 281.816 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 74.88 using 59 PHA bins.
# Reduced chi-squared = 1.337 for 56 degrees of freedom
# Null hypothesis probability = 4.678397e-02
Photon flux (15-150 keV) in 1 sec: 0.599090 ( -0.142392 0.143877 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.46596e-08 ( -9.9969e-09 1.44106e-08 ) ergs/cm2
Band function
Time interval is from -4.364 sec. to -3.364 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 1.46363 ( -2.82341 -1.50727 )
beta : -2.74560 ( 2.75685 0.961254 )
Epeak [keV] : 39.0391 ( -11.4894 25.3829 )
Norm@50keV : 0.462219 ( -0.576327 44.7965 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 73.80 using 59 PHA bins.
# Reduced chi-squared = 1.342 for 55 degrees of freedom
# Null hypothesis probability = 4.612397e-02
Photon flux (15-150 keV) in 1 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 3.81949e-08 ( 0 0 ) ergs/cm2
Single BB
Spectral model blackbody:
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 10.5406 (-1.95328 2.54032)
R^2/D10^2 : 0.268440 (-0.149208 0.304712)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 75.04 using 59 PHA bins.
# Reduced chi-squared = 1.316 for 57 degrees of freedom
# Null hypothesis probability = 5.490710e-02
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 6.171e-09 2.483e-09
25- 50 1.650e-08 5.255e-09
50-150 1.001e-08 5.075e-09
15-150 3.268e-08 1.240e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 93.9756 (-46.8616 -93.9759)
Norm : 2.94264 (-0.699104 1.01823)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 76.50 using 59 PHA bins.
# Reduced chi-squared = 1.342 for 57 degrees of freedom
# Null hypothesis probability = 4.338956e-02
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 7.686e-09 3.015e-09
25- 50 1.312e-08 6.883e-09
50-150 2.051e-08 1.521e-08
15-150 4.132e-08 2.603e-08
Double BB
R1^2/D10^2 : 1.32282E+06 ( )
kT2 [keV] : 10.8509 (-2.01906 2.79605)
R2^2/D10^2 : 0.236633 (-0.100469 0.271828)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 75.04 using 59 PHA bins.
#Fit statistic : Chi-Squared = 74.38 using 59 PHA bins.
#Fit statistic : Chi-Squared = 74.26 using 59 PHA bins.
# Reduced chi-squared = 1.364 for 55 degrees of freedom
# Reduced chi-squared = 1.352 for 55 degrees of freedom
# Reduced chi-squared = 1.350 for 55 degrees of freedom
# Null hypothesis probability = 3.756295e-02
# Null hypothesis probability = 4.190865e-02
# Null hypothesis probability = 4.278686e-02
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
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: 1.69966 ( -0.139451 0.142568 )
Norm@50keV : 2.13935E-03 ( -0.000182209 0.000179848 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 55.93 using 59 PHA bins.
# Reduced chi-squared = 0.9813 for 57 degrees of freedom
# Null hypothesis probability = 5.152077e-01
Photon flux (15-150 keV) in 44.84 sec: 0.284095 ( -0.0215137 0.021525 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.88204e-07 ( -7.9543e-08 8.06748e-08 ) ergs/cm2
Cutoff power-law model
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.42250 ( -0.583181 0.390608 )
Epeak [keV] : 95.2949 ( )
Norm@50keV : 3.02130E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 55.12 using 59 PHA bins.
# Reduced chi-squared = 0.9843 for 56 degrees of freedom
# Null hypothesis probability = 5.081077e-01
Photon flux (15-150 keV) in 44.84 sec: 0.280136 ( -0.022735 0.022701 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.62771e-07 ( -9.24287e-08 9.1366e-08 ) ergs/cm2
Band function
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.36737 ( 1.36739 1.36739 )
beta : -2.27195 ( 2.23002 10.906 )
Epeak [keV] : 89.2595 ( -89.2446 -89.2446 )
Norm@50keV : 3.19915E-03 ( -0.00121802 0 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 55.14 using 59 PHA bins.
# Reduced chi-squared = 1.002 for 55 degrees of freedom
# Null hypothesis probability = 4.694456e-01
Photon flux (15-150 keV) in 44.84 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) = 3.47e-07
S(50-100 keV) = 4.14e-07
T90 vs. Hardness ratio plot
T90 = 105.728000044823 sec.
Hardness ratio (energy fluence ratio) = 1.19308
Color vs. Color plot
Count Ratio (25-50 keV) / (15-25 keV) = 1.19866
Count Ratio (50-100 keV) / (15-25 keV) = 0.688554
Mask shadow pattern
IMX = -2.334325516077084E-01, IMY = 2.134160851587494E-01
TIME vs. PHA plot around the trigger time
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 4.096000
TIME vs. DetID plot around the trigger time
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 4.096000
100 us light curve (15-350 keV)
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 4.096000
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:
-239.504000 -10.048000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
82.9200 53.9723 2.7 23.6 61.8 1.0515 4.3 ------ UNKNOWN
105.3448 63.8587 2.6 28.9 29.4 0.9286 4.5 ------ UNKNOWN
345.2744 27.7180 2.8 49.2 -133.7 3.5621 4.2 ------ UNKNOWN
322.9180 52.0906 3.8 40.8 -93.0 2.9057 3.1 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image:
-10.048000 34.796620
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
117.7191 49.4308 2.5 42.9 42.5 1.0308 4.7 ------ UNKNOWN
13.1510 51.5706 0.5 17.6 -137.6 1.6337 21.1 ------ UNKNOWN
5.2019 53.0108 2.3 20.3 -124.4 0.4148 5.1 ------ UNKNOWN
307.0137 60.5646 2.4 41.4 -74.5 1.5133 4.8 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image:
76.796600 962.645900
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
326.3728 38.3694 40.4 34.9 -85.6 -0.3844 -0.3 9.9 Cyg X-2
99.1047 65.7071 3.1 42.9 45.1 6.7267 3.8 ------ UNKNOWN
74.0977 65.2596 2.3 33.1 50.1 4.9467 5.0 ------ UNKNOWN
359.2853 43.0742 3.1 12.6 -119.0 2.0308 3.8 ------ UNKNOWN
249.1867 73.0915 3.7 49.5 -10.5 3.3371 3.1 ------ UNKNOWN
274.9566 62.2614 3.0 49.3 -29.4 4.6213 3.9 ------ UNKNOWN
258.9197 58.6340 3.8 57.5 -26.2 9.7088 3.0 ------ UNKNOWN
Plot creation:
Sat May 30 20:50:16 EDT 2015