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
7.8216 -33.7481 0.0064 18.5157 -12.0979 0.8527661 30.052 TRIG_00217805
Foreground time interval of the image:
-0.260 10.181 (delta_t = 10.441 [sec])
Background time interval of the image:
-239.320 -0.260 (delta_t = 239.060 [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 -0.260 sec. to 14.176 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.64057 ( -0.116532 0.118324 )
Norm@50keV : 3.70845E-03 ( -0.000257961 0.000255974 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 60.90 using 59 PHA bins.
# Reduced chi-squared = 1.068 for 57 degrees of freedom
# Null hypothesis probability = 3.373225e-01
Photon flux (15-150 keV) in 14.44 sec: 0.482738 ( -0.0316276 0.0316572 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.98515e-07 ( -3.70442e-08 3.7384e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.260 sec. to 14.176 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.21956 ( -0.495065 0.441972 )
Epeak [keV] : 88.9475 ( -25.8019 -88.9475 )
Norm@50keV : 6.14165E-03 ( -0.00247883 0.00482136 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.29 using 59 PHA bins.
# Reduced chi-squared = 1.041 for 56 degrees of freedom
# Null hypothesis probability = 3.910468e-01
Photon flux (15-150 keV) in 14.44 sec: 0.472529 ( -0.033374 0.033351 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.8057e-07 ( -4.15482e-08 4.1863e-08 ) ergs/cm2
Band function
Time interval is from -0.260 sec. to 14.176 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.21960 ( -0.441879 0.49062 )
beta : -10.0000 ( 10 20 )
Epeak [keV] : 88.9396 ( -22.1347 -88.9396 )
Norm@50keV : 6.14053E-03 ( -0.00247732 0.00482322 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.29 using 59 PHA bins.
# Reduced chi-squared = 1.060 for 55 degrees of freedom
# Null hypothesis probability = 3.552418e-01
Photon flux (15-150 keV) in 14.44 sec: 0.471996 ( 6.528 -0.03282 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.80247e-07 ( 0 0 ) ergs/cm2
Single BB
Spectral model blackbody:
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 13.5672 (-1.12013 1.22965)
R^2/D10^2 : 7.50005E-02 (-0.0200477 0.0272554)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 108.18 using 59 PHA bins.
# Reduced chi-squared = 1.8980 for 57 degrees of freedom
# Null hypothesis probability = 5.062617e-05
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 4.221e-08 4.744e-09
25- 50 1.521e-07 1.259e-08
50-150 1.813e-07 2.693e-08
15-150 3.756e-07 3.126e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 156.135 (-44.3642 -155.198)
Norm : 1.98128 (-0.141009 0.172426)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.40 using 59 PHA bins.
# Reduced chi-squared = 1.025 for 57 degrees of freedom
# Null hypothesis probability = 4.238131e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 7.322e-08 6.274e-09
25- 50 1.365e-07 2.244e-08
50-150 2.739e-07 1.096e-07
15-150 4.836e-07 1.308e-07
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 5.79905 (-1.26394 1.51509)
R1^2/D10^2 : 0.969100 (-0.537193 1.55171)
kT2 [keV] : 21.2001 (-3.26192 5.07857)
R2^2/D10^2 : 1.23182E-02 (-0.00691688 0.0112564)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.55 using 59 PHA bins.
# Reduced chi-squared = 1.046 for 55 degrees of freedom
# Null hypothesis probability = 3.811131e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 7.449e-08 2.307e-08
25- 50 1.328e-07 3.213e-08
50-150 2.651e-07 7.097e-08
15-150 4.723e-07 1.123e-07
Peak spectrum fit
Power-law model
Time interval is from 1.120 sec. to 2.120 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.33091 ( -0.118367 0.118322 )
Norm@50keV : 1.59181E-02 ( -0.00111959 0.00111841 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.82 using 59 PHA bins.
# Reduced chi-squared = 1.049 for 57 degrees of freedom
# Null hypothesis probability = 3.737892e-01
Photon flux (15-150 keV) in 1 sec: 1.91031 ( -0.136007 0.136125 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.56147e-07 ( -1.223e-08 1.23006e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 1.120 sec. to 2.120 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.844645 ( -0.526872 0.469738 )
Epeak [keV] : 121.922 ( -39.5078 1099.55 )
Norm@50keV : 2.77833E-02 ( -0.0113413 0.02231 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.68 using 59 PHA bins.
# Reduced chi-squared = 1.012 for 56 degrees of freedom
# Null hypothesis probability = 4.493155e-01
Photon flux (15-150 keV) in 1 sec: 1.87560 ( -0.14021 0.14015 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.51076e-07 ( -1.3441e-08 1.3366e-08 ) ergs/cm2
Band function
Time interval is from 1.120 sec. to 2.120 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 1.22634 ( -1.50177 -0.390407 )
beta : -1.54282 ( 1.5376 0.200077 )
Epeak [keV] : 42.2668 ( -24.5091 127.93 )
Norm@50keV : 0.661076 ( -0.663892 120.476 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.28 using 59 PHA bins.
# Reduced chi-squared = 0.9870 for 55 degrees of freedom
# Null hypothesis probability = 5.019840e-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] : 16.2022 (-1.42675 1.60885)
R^2/D10^2 : 0.174032 (-0.0482816 0.0649874)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 91.79 using 59 PHA bins.
# Reduced chi-squared = 1.610 for 57 degrees of freedom
# Null hypothesis probability = 2.384571e-03
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 9.419e-09 1.264e-09
25- 50 4.006e-08 4.115e-09
50-150 7.385e-08 9.770e-09
15-150 1.233e-07 1.025e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 200.000 ( )
Norm : 7.90109 (-0.554487 0.554454)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 66.58 using 59 PHA bins.
# Reduced chi-squared = 1.168 for 57 degrees of freedom
# Null hypothesis probability = 1.807080e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.968e-08 1.595e-09
25- 50 3.785e-08 4.060e-09
50-150 8.302e-08 2.358e-08
15-150 1.405e-07 3.448e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 9.10672 (-1.84144 2.01796)
R1^2/D10^2 : 0.799348 (-0.343938 0.734545)
kT2 [keV] : 33.5983 (-8.59572 22.6616)
R2^2/D10^2 : 1.09800E-02 (-0.00858363 0.0123231)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 53.75 using 59 PHA bins.
# Reduced chi-squared = 0.9773 for 55 degrees of freedom
# Null hypothesis probability = 5.223356e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.479e-08 3.830e-09
25- 50 3.973e-08 1.028e-08
50-150 9.903e-08 4.368e-08
15-150 1.535e-07 5.449e-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: 1.58842 ( -0.104944 0.10614 )
Norm@50keV : 4.94590E-03 ( -0.000307692 0.000306146 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.34 using 59 PHA bins.
# Reduced chi-squared = 1.041 for 57 degrees of freedom
# Null hypothesis probability = 3.904805e-01
Photon flux (15-150 keV) in 10.44 sec: 0.633314 ( -0.0381636 0.0382052 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.83593e-07 ( -3.24716e-08 3.27125e-08 ) ergs/cm2
Cutoff power-law model
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.00475 ( -0.466826 0.421878 )
Epeak [keV] : 83.5956 ( -18.3528 84.4487 )
Norm@50keV : 9.82086E-03 ( -0.00376039 0.00695749 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 53.54 using 59 PHA bins.
# Reduced chi-squared = 0.9560 for 56 degrees of freedom
# Null hypothesis probability = 5.685884e-01
Photon flux (15-150 keV) in 10.44 sec: 0.614761 ( -0.040325 0.040322 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.61348e-07 ( -3.60441e-08 3.63322e-08 ) ergs/cm2
Band function
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.00482 ( -0.448519 0.438561 )
beta : -10.0000 ( 10 6.03961e-14 )
Epeak [keV] : 83.5898 ( -18.3644 84.3263 )
Norm@50keV : 9.81905E-03 ( -0.00375893 0.00696671 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 53.54 using 59 PHA bins.
# Reduced chi-squared = 0.9734 for 55 degrees of freedom
# Null hypothesis probability = 5.306124e-01
Photon flux (15-150 keV) in 10.44 sec: 0.614378 ( 6.38562 -0.037181 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.63277e-07 ( 0 0 ) ergs/cm2
S(25-50 keV) vs. S(50-100 keV) plot
S(25-50 keV) = 1.32e-07
S(50-100 keV) = 1.69e-07
T90 vs. Hardness ratio plot
T90 = 10.027999997139 sec.
Hardness ratio (energy fluence ratio) = 1.2803
Color vs. Color plot
Count Ratio (25-50 keV) / (15-25 keV) = 1.23394
Count Ratio (50-100 keV) / (15-25 keV) = 0.853864
Mask shadow pattern
IMX = 3.274621348539180E-01, IMY = 7.018943057258914E-02
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:
-239.320000 -0.260000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
333.5886 24.9389 2.3 48.6 168.2 1.8946 5.0 ------ UNKNOWN
19.3824 -69.5483 2.7 53.4 7.5 2.6420 4.2 ------ UNKNOWN
8.1104 -10.2665 3.0 13.1 -107.1 0.5442 3.8 ------ UNKNOWN
356.8363 41.4005 3.9 59.3 -163.2 3.4776 3.0 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image:
-0.260000 10.180600
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
7.8217 -33.7481 0.4 18.5 -12.1 0.8526 30.0 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image:
51.380600 408.280600
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
339.8295 -75.4756 3.1 43.8 24.0 1.6843 3.8 ------ UNKNOWN
66.3741 -81.4291 2.6 52.1 4.9 2.5906 4.5 ------ UNKNOWN
27.6975 -65.2923 2.5 33.8 -0.6 1.2640 4.7 ------ UNKNOWN
36.5486 -58.2088 2.4 31.1 -15.2 0.9895 4.8 ------ UNKNOWN
51.2481 -65.6604 2.3 41.0 -11.4 1.4287 5.1 ------ UNKNOWN
91.7792 -58.7525 2.9 58.7 -22.9 5.3874 3.9 ------ UNKNOWN
50.7217 -25.6886 3.0 37.9 -76.4 2.0149 3.9 ------ UNKNOWN
Plot creation:
Sun May 31 12:42:25 EDT 2015