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
37.8570 -1.5846 0.0214 26.4498 -79.7501 0.2406071 9.011 TRIG_00585128
Foreground time interval of the image:
0.992 3.992 (delta_t = 3.000 [sec])
Background time interval of the image:
-93.507 0.992 (delta_t = 94.499 [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 0.992 sec. to 3.992 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.96543 ( -0.312558 0.342146 )
Norm@50keV : 4.62180E-03 ( -0.00105494 0.00101714 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 53.44 using 59 PHA bins.
# Reduced chi-squared = 0.9376 for 57 degrees of freedom
# Null hypothesis probability = 6.092528e-01
Photon flux (15-150 keV) in 3 sec: 0.682478 ( -0.117304 0.117304 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.27666e-07 ( -2.69965e-08 2.8111e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.992 sec. to 3.992 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.467600 ( -4.6421 1.67992 )
Epeak [keV] : 38.2094 ( )
Norm@50keV : 3.86237E-02 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 52.60 using 59 PHA bins.
# Reduced chi-squared = 0.9392 for 56 degrees of freedom
# Null hypothesis probability = 6.045330e-01
Photon flux (15-150 keV) in 3 sec: 0.645373 ( -0.117611 0.135679 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.06067e-07 ( -2.75082e-08 4.47006e-08 ) ergs/cm2
Band function
Time interval is from 0.992 sec. to 3.992 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 0.466697 ( -0.70066 3.37346 )
beta : -2.98136 ( 3.01037 1.173 )
Epeak [keV] : 36.7348 ( -36.7692 24.2654 )
Norm@50keV : 0.148900 ( -0.133921 20.654 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 51.14 using 59 PHA bins.
# Reduced chi-squared = 0.9297 for 55 degrees of freedom
# Null hypothesis probability = 6.230173e-01
Photon flux (15-150 keV) in 3 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] : 9.42226 (-1.40982 1.68632)
R^2/D10^2 : 0.416324 (-0.197915 0.359945)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 52.96 using 59 PHA bins.
# Reduced chi-squared = 0.9291 for 57 degrees of freedom
# Null hypothesis probability = 6.274018e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.207e-08 7.833e-09
25- 50 5.031e-08 1.307e-08
50-150 2.204e-08 1.002e-08
15-150 9.442e-08 2.438e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 63.2938 (-25.6124 63.7719)
Norm : 3.51340 (-0.884375 1.21581)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 52.80 using 59 PHA bins.
# Reduced chi-squared = 0.9263 for 57 degrees of freedom
# Null hypothesis probability = 6.333977e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.671e-08 6.271e-09
25- 50 4.130e-08 1.047e-08
50-150 4.909e-08 2.744e-08
15-150 1.171e-07 3.932e-08
Double BB
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 8.33301 ( )
R1^2/D10^2 : 0.616788 (-0.257765 0.551721)
kT2 [keV] : 99.8381 (-171.76 -199.155)
R2^2/D10^2 : 1.63838E-04 (-3.80589e-05 0.00286662)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 50.70 using 59 PHA bins.
#Fit statistic : Chi-Squared = 48.54 using 59 PHA bins.
# Reduced chi-squared = 0.9218 for 55 degrees of freedom
# Reduced chi-squared = 0.8825 for 55 degrees of freedom
# Null hypothesis probability = 6.395946e-01
# Null hypothesis probability = 7.183085e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.469e-08 1.000e-08
25- 50 4.743e-08 2.711e-08
50-150 2.561e-08 1.695e-08
15-150 9.772e-08 5.393e-08
Peak spectrum fit
Power-law model
Time interval is from 1.992 sec. to 2.992 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.61677 ( -0.425897 0.459123 )
Norm@50keV : 6.75408E-03 ( -0.00179547 0.00171346 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 34.97 using 59 PHA bins.
# Reduced chi-squared = 0.6134 for 57 degrees of freedom
# Null hypothesis probability = 9.905602e-01
Photon flux (15-150 keV) in 1 sec: 0.872497 ( -0.206049 0.20622 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.30401e-08 ( -1.74488e-08 1.79275e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 1.992 sec. to 2.992 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.80904 ( )
Epeak [keV] : 249.108 ( )
Norm@50keV : 1.69381E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 34.08 using 59 PHA bins.
# Reduced chi-squared = 0.6086 for 56 degrees of freedom
# Null hypothesis probability = 9.909077e-01
Photon flux (15-150 keV) in 1 sec: 0.873155 ( -0.207016 0.205345 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.28216e-08 ( -1.78791e-08 1.79707e-08 ) ergs/cm2
Band function
Time interval is from 1.992 sec. to 2.992 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -9.07310 ( 9.0731 9.0731 )
beta : -1.61677 ( -0.459166 0.425895 )
Epeak [keV] : 68.3486 ( -68.3486 -68.3486 )
Norm@50keV : 0.917975 ( -0.244031 0.232888 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 34.97 using 59 PHA bins.
# Reduced chi-squared = 0.6357 for 55 degrees of freedom
# Null hypothesis probability = 9.839467e-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] : 11.7686 (-3.07195 5.26797)
R^2/D10^2 : 0.226544 (-0.165898 0.449342)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 40.78 using 59 PHA bins.
# Reduced chi-squared = 0.7154 for 57 degrees of freedom
# Null hypothesis probability = 9.483884e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 6.624e-09 3.303e-09
25- 50 2.037e-08 1.004e-08
50-150 1.674e-08 9.828e-09
15-150 4.374e-08 2.430e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 177.421 (-115.844 -178.037)
Norm : 3.55764 (-0.851781 1.21362)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 35.29 using 59 PHA bins.
# Reduced chi-squared = 0.6191 for 57 degrees of freedom
# Null hypothesis probability = 9.894451e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 8.986e-09 5.255e-09
25- 50 1.704e-08 9.695e-09
50-150 3.590e-08 2.132e-08
15-150 6.193e-08 3.596e-08
Double BB
R1^2/D10^2 : 0.635200 (-24993.2 -24998.2)
kT2 [keV] : 44.3249 ( )
R2^2/D10^2 : 1.86328E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 36.22 using 59 PHA bins.
#Fit statistic : Chi-Squared = 34.59 using 59 PHA bins.
#Fit statistic : Chi-Squared = 34.56 using 59 PHA bins.
# Reduced chi-squared = 0.6585 for 55 degrees of freedom
# Reduced chi-squared = 0.6289 for 55 degrees of freedom
# Reduced chi-squared = 0.6284 for 55 degrees of freedom
# Null hypothesis probability = 9.762876e-01
# Null hypothesis probability = 9.858123e-01
# Null hypothesis probability = 9.859319e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 7.646e-09 3.331e-09
25- 50 1.789e-08 9.991e-09
50-150 2.234e-08 1.509e-08
15-150 4.788e-08 2.297e-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: 1.96543 ( -0.312558 0.342146 )
Norm@50keV : 4.62180E-03 ( -0.00105494 0.00101714 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 53.44 using 59 PHA bins.
# Reduced chi-squared = 0.9376 for 57 degrees of freedom
# Null hypothesis probability = 6.092528e-01
Photon flux (15-150 keV) in 3 sec: 0.682478 ( -0.117304 0.117304 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.27666e-07 ( -2.69965e-08 2.8111e-08 ) ergs/cm2
Cutoff power-law model
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.467600 ( -4.6421 1.72316 )
Epeak [keV] : 38.2094 ( )
Norm@50keV : 3.86237E-02 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 52.60 using 59 PHA bins.
# Reduced chi-squared = 0.9392 for 56 degrees of freedom
# Null hypothesis probability = 6.045330e-01
Photon flux (15-150 keV) in 3 sec: 0.645373 ( -0.117611 0.135679 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.06067e-07 ( -2.75082e-08 4.47006e-08 ) ergs/cm2
Band function
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 0.466697 ( -0.70066 3.37346 )
beta : -2.98136 ( 3.01037 1.173 )
Epeak [keV] : 36.7348 ( -36.7692 24.2654 )
Norm@50keV : 0.148900 ( -0.133921 20.654 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 51.14 using 59 PHA bins.
# Reduced chi-squared = 0.9297 for 55 degrees of freedom
# Null hypothesis probability = 6.230173e-01
Photon flux (15-150 keV) in 3 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) = 3.80e-08
S(50-100 keV) = 3.90e-08
T90 vs. Hardness ratio plot
T90 = 3 sec.
Hardness ratio (energy fluence ratio) = 1.02632
Color vs. Color plot
Count Ratio (25-50 keV) / (15-25 keV) = 1.35027
Count Ratio (50-100 keV) / (15-25 keV) = 0.311275
Mask shadow pattern
IMX = 8.852375190618189E-02, IMY = 4.895486352470583E-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:
-93.507400 0.992000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
83.6285 22.0173 0.6 28.2 56.8 3.5223 18.6 0.3 Crab
40.7639 -27.3292 2.3 36.3 -127.3 1.0087 5.1 ------ UNKNOWN
31.0869 -33.4299 2.3 46.5 -125.1 3.0526 4.9 ------ UNKNOWN
32.2592 -36.7258 2.8 48.0 -129.2 2.4079 4.1 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image:
0.992000 3.992000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
83.6298 22.0135 201.4 28.2 56.8 0.0017 0.1 0.2 Crab
96.4971 -25.7720 2.3 41.2 149.0 0.2283 5.0 ------ UNKNOWN
56.9724 -33.0660 3.2 34.8 -153.4 0.0925 3.6 ------ UNKNOWN
37.8569 -1.5845 1.3 26.4 -79.8 0.2406 9.0 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image:
97.892640 963.052000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
27.9265 47.4822 3.0 49.8 9.3 5.2976 3.8 ------ UNKNOWN
359.5146 -18.1996 4.3 41.1 -98.2 8.6056 2.7 ------ UNKNOWN
Plot creation:
Sat May 30 14:36:18 EDT 2015