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
137.0875 -54.4364 0.0100 51.8277 172.1188 3.7220116 19.141 TRIG_00529021
Foreground time interval of the image:
-0.040 24.136 (delta_t = 24.176 [sec])
Background time interval of the image:
-282.811 -267.604 (delta_t = 15.207 [sec])
-239.512 -0.040 (delta_t = 239.472 [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 12.160000
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 12.160000
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 12.160000
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 -0.040 sec. to 24.136 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.76763 ( -0.125577 0.127801 )
Norm@50keV : 1.07370E-02 ( -0.000803917 0.000798789 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.26 using 59 PHA bins.
# Reduced chi-squared = 0.9870 for 57 degrees of freedom
# Null hypothesis probability = 5.029133e-01
Photon flux (15-150 keV) in 24.18 sec: 1.46138 ( -0.109345 0.109659 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.39338e-06 ( -1.83339e-07 1.84153e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.040 sec. to 24.136 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.38904 ( -0.528142 0.434116 )
Epeak [keV] : 80.8840 ( -23.2744 -80.884 )
Norm@50keV : 1.66689E-02 ( -0.00637165 0.0136086 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.41 using 59 PHA bins.
# Reduced chi-squared = 0.9716 for 56 degrees of freedom
# Null hypothesis probability = 5.353678e-01
Photon flux (15-150 keV) in 24.18 sec: 1.43321 ( -0.11478 0.11489 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.33941e-06 ( -1.97244e-07 1.96956e-07 ) ergs/cm2
Band function
Time interval is from -0.040 sec. to 24.136 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.38909 ( -0.47931 0.485612 )
beta : -10.0000 ( 10 0 )
Epeak [keV] : 80.8756 ( -22.2571 -80.8756 )
Norm@50keV : 1.66652E-02 ( -0.00643496 0.0136097 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.41 using 59 PHA bins.
# Reduced chi-squared = 0.9892 for 55 degrees of freedom
# Null hypothesis probability = 4.972308e-01
Photon flux (15-150 keV) in 24.18 sec: 1.43264 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 2.33358e-06 ( 0 0 ) ergs/cm2
Single BB
Spectral model blackbody:
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 13.7957 (-1.22908 1.33389)
R^2/D10^2 : 0.207773 (-0.0601902 0.08552)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 102.92 using 59 PHA bins.
# Reduced chi-squared = 1.8057 for 57 degrees of freedom
# Null hypothesis probability = 1.870624e-04
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.022e-07 2.842e-08
25- 50 7.411e-07 7.073e-08
50-150 9.217e-07 1.336e-07
15-150 1.865e-06 1.655e-07
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 121.186 (-30.1471 44.9204)
Norm : 6.14693 (-0.567321 0.691817)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.56 using 59 PHA bins.
# Reduced chi-squared = 0.9573 for 57 degrees of freedom
# Null hypothesis probability = 5.669769e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 3.870e-07 4.244e-08
25- 50 6.935e-07 6.662e-08
50-150 1.244e-06 4.280e-07
15-150 2.324e-06 4.669e-07
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 5.65650 (-1.18429 1.45707)
R1^2/D10^2 : 3.61420 (-2.07483 5.86295)
kT2 [keV] : 21.1027 (-3.16027 4.84501)
R2^2/D10^2 : 3.50505E-02 (-0.0195327 0.0318915)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 52.98 using 59 PHA bins.
# Reduced chi-squared = 0.9632 for 55 degrees of freedom
# Null hypothesis probability = 5.523642e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 4.108e-07 1.453e-07
25- 50 6.640e-07 1.659e-07
50-150 1.239e-06 3.125e-07
15-150 2.314e-06 5.668e-07
Peak spectrum fit
Power-law model
Time interval is from 12.268 sec. to 13.268 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.09890 ( -0.390241 0.447067 )
Norm@50keV : 1.56193E-02 ( -0.00425371 0.00397937 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 60.94 using 59 PHA bins.
# Reduced chi-squared = 1.069 for 57 degrees of freedom
# Null hypothesis probability = 3.361801e-01
Photon flux (15-150 keV) in 1 sec: 2.45598 ( -0.53264 0.533945 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.45104e-07 ( -3.46105e-08 3.51581e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 12.268 sec. to 13.268 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.98347 ( )
Epeak [keV] : 8.77053 ( )
Norm@50keV : 1.76000E-02 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 61.03 using 59 PHA bins.
# Reduced chi-squared = 1.090 for 56 degrees of freedom
# Null hypothesis probability = 3.001294e-01
Photon flux (15-150 keV) in 1 sec: 2.45774 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 1.4465e-07 ( -3.4843e-08 2.6644e-08 ) ergs/cm2
Band function
Time interval is from 12.268 sec. to 13.268 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -8.35574 ( 8.35574 8.35574 )
beta : -2.09891 ( -0.447063 0.39034 )
Epeak [keV] : 16.9000 ( -16.9 -16.9 )
Norm@50keV : 2.12287 ( -0.578136 0.540857 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 60.94 using 59 PHA bins.
# Reduced chi-squared = 1.108 for 55 degrees of freedom
# Null hypothesis probability = 2.708771e-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] : 10.0747 (-2.33221 3.07529)
R^2/D10^2 : 1.07943 (-0.698894 1.94894)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 67.56 using 59 PHA bins.
# Reduced chi-squared = 1.185 for 57 degrees of freedom
# Null hypothesis probability = 1.596740e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.237e-08 9.984e-09
25- 50 5.620e-08 2.908e-08
50-150 2.997e-08 1.714e-08
15-150 1.085e-07 4.566e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 63.9155 (-29.4741 82.1784)
Norm : 12.3466 (-3.86607 6.11949)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 61.93 using 59 PHA bins.
# Reduced chi-squared = 1.086 for 57 degrees of freedom
# Null hypothesis probability = 3.046858e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 3.133e-08 8.710e-09
25- 50 4.859e-08 1.330e-08
50-150 5.820e-08 3.276e-08
15-150 1.381e-07 4.996e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 2.11204 (-1.48247 -2.05548)
R1^2/D10^2 : 1303.09 (-1677.1 -1685.38)
kT2 [keV] : 12.4391 (-3.27776 10.3212)
R2^2/D10^2 : 0.427908 (-0.390008 0.445776)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 61.33 using 59 PHA bins.
# Reduced chi-squared = 1.115 for 55 degrees of freedom
# Null hypothesis probability = 2.594073e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 3.316e-08 1.622e-08
25- 50 4.671e-08 2.762e-08
50-150 4.384e-08 2.798e-08
15-150 1.237e-07 6.547e-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: 1.76763 ( -0.125577 0.127801 )
Norm@50keV : 1.07370E-02 ( -0.000803917 0.000798789 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.26 using 59 PHA bins.
# Reduced chi-squared = 0.9870 for 57 degrees of freedom
# Null hypothesis probability = 5.029133e-01
Photon flux (15-150 keV) in 24.18 sec: 1.46138 ( -0.109345 0.109659 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.39338e-06 ( -1.83339e-07 1.84153e-07 ) ergs/cm2
Cutoff power-law model
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.38904 ( -0.528142 0.434116 )
Epeak [keV] : 80.8840 ( -23.2744 -80.884 )
Norm@50keV : 1.66689E-02 ( -0.00637165 0.0136086 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.41 using 59 PHA bins.
# Reduced chi-squared = 0.9716 for 56 degrees of freedom
# Null hypothesis probability = 5.353678e-01
Photon flux (15-150 keV) in 24.18 sec: 1.43321 ( -0.11478 0.11489 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.33941e-06 ( -1.97244e-07 1.96956e-07 ) ergs/cm2
Band function
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.38909 ( -0.441276 0.485579 )
beta : -10.0000 ( 10 3.55271e-15 )
Epeak [keV] : 80.8756 ( -22.2571 -80.8756 )
Norm@50keV : 1.66652E-02 ( -0.00643496 0.0136097 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.41 using 59 PHA bins.
# Reduced chi-squared = 0.9892 for 55 degrees of freedom
# Null hypothesis probability = 4.972308e-01
Photon flux (15-150 keV) in 24.18 sec: 1.43264 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 2.33358e-06 ( 0 0 ) ergs/cm2
S(25-50 keV) vs. S(50-100 keV) plot
S(25-50 keV) = 6.66e-07
S(50-100 keV) = 7.82e-07
T90 vs. Hardness ratio plot
T90 = 20.9760000705719 sec.
Hardness ratio (energy fluence ratio) = 1.17417
Color vs. Color plot
Count Ratio (25-50 keV) / (15-25 keV) = 1.20345
Count Ratio (50-100 keV) / (15-25 keV) = 0.919518
Mask shadow pattern
IMX = -1.260021987066310E+00, IMY = -1.744211878268362E-01
TIME vs. PHA plot around the trigger time
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 12.160000
TIME vs. DetID plot around the trigger time
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 12.160000
100 us light curve (15-350 keV)
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 12.160000
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:
-282.811400 -267.604500
-239.512000 -0.040000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
135.5739 -40.5805 3.3 46.0 -171.1 1.2061 3.6 2.6 Vela X-1
170.3448 -60.4657 0.0 46.9 148.3 -1.4939 -2.3 9.5 Cen X-3
216.4911 22.8161 2.3 52.2 8.4 2.9769 5.1 ------ UNKNOWN
120.5398 -43.4308 2.4 57.5 -170.3 4.4711 4.9 ------ UNKNOWN
158.0046 1.8119 3.3 25.8 -91.3 0.8930 3.5 ------ UNKNOWN
145.7339 -5.0220 2.7 33.6 -115.2 1.3167 4.3 ------ UNKNOWN
147.4436 12.6100 2.9 40.8 -88.1 3.5455 3.9 ------ UNKNOWN
134.1042 -4.6307 2.5 44.9 -119.7 3.8766 4.6 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image:
-0.040000 24.136000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
135.5190 -40.6201 3.9 46.0 -171.1 0.2873 3.0 3.9 Vela X-1
170.1952 -60.5208 4.2 47.0 148.4 -0.5219 -2.8 7.1 Cen X-3
213.8605 -23.1753 2.8 34.5 73.5 0.4602 4.1 ------ UNKNOWN
205.7805 -13.5897 1.8 26.3 55.3 0.4405 6.6 ------ UNKNOWN
137.0875 -54.4364 0.6 51.8 172.1 3.7223 19.1 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image:
131.788600 962.518000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
135.5250 -40.5605 1.1 13.9 -86.5 5.0133 10.3 0.4 Vela X-1
170.5737 -60.6192 5.7 18.7 41.3 0.9099 2.0 7.6 Cen X-3
186.6511 -62.7769 0.6 26.3 47.0 10.0314 19.6 0.4 GX 301-2
107.0460 -52.9894 2.9 17.7 -179.0 1.6490 4.0 ------ UNKNOWN
181.1050 -28.3003 2.7 41.0 -12.8 2.5129 4.3 ------ UNKNOWN
128.9574 -43.2433 1.3 12.4 -110.2 3.9980 8.8 ------ UNKNOWN
102.5286 -14.6962 2.5 48.0 -129.1 11.1502 4.7 ------ UNKNOWN
Plot creation:
Sat May 30 19:03:36 EDT 2015