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
273.0751 14.2965 0.0075 21.1147 54.2487 0.6593838 25.716 TRIG_00517469
Foreground time interval of the image:
-1.376 3.228 (delta_t = 4.604 [sec])
Background time interval of the image:
-213.003 -1.376 (delta_t = 211.627 [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 0.256000
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 0.256000
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 0.256000
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 -1.376 sec. to 3.228 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.29308 ( -0.150109 0.157243 )
Norm@50keV : 6.73011E-03 ( -0.000698384 0.000686575 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 46.57 using 59 PHA bins.
# Reduced chi-squared = 0.8170 for 57 degrees of freedom
# Null hypothesis probability = 8.365582e-01
Photon flux (15-150 keV) in 4.604 sec: 1.17164 ( -0.0877726 0.087857 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.95727e-07 ( -2.52081e-08 2.55681e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -1.376 sec. to 3.228 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.94088 ( -0.704285 0.0567269 )
Epeak [keV] : 6.66037 ( -5.53853 24.5235 )
Norm@50keV : 1.08914E-02 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 45.59 using 59 PHA bins.
# Reduced chi-squared = 0.8142 for 56 degrees of freedom
# Null hypothesis probability = 8.383667e-01
Photon flux (15-150 keV) in 4.604 sec: 1.15343 ( -0.09299 0.09275 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.85124e-07 ( -3.0159e-08 3.06065e-08 ) ergs/cm2
Band function
Time interval is from -1.376 sec. to 3.228 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.76941 ( 1.77345 1.77345 )
beta : -2.58869 ( 2.58823 0.405422 )
Epeak [keV] : 16.3567 ( -16.04 11.9424 )
Norm@50keV : 1.40890E-02 ( -0.00497673 2600.2 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 45.28 using 59 PHA bins.
# Reduced chi-squared = 0.8232 for 55 degrees of freedom
# Null hypothesis probability = 8.221186e-01
Photon flux (15-150 keV) in 4.604 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] : 8.49878 (-0.740657 0.807381)
R^2/D10^2 : 0.967105 (-0.299112 0.438444)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 82.06 using 59 PHA bins.
# Reduced chi-squared = 1.440 for 57 degrees of freedom
# Null hypothesis probability = 1.650885e-02
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 6.061e-08 7.458e-09
25- 50 1.175e-07 1.008e-08
50-150 3.750e-08 8.939e-09
15-150 2.156e-07 1.814e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 43.4689 (-7.92875 10.5453)
Norm : 7.07323 (-1.01929 1.22779)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 47.69 using 59 PHA bins.
# Reduced chi-squared = 0.8366 for 57 degrees of freedom
# Null hypothesis probability = 8.054732e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 7.677e-08 6.906e-09
25- 50 1.046e-07 8.402e-09
50-150 8.838e-08 1.968e-08
15-150 2.697e-07 2.576e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 4.87917 (-1.16743 1.35878)
R1^2/D10^2 : 6.69348 (-3.9871 14.1731)
kT2 [keV] : 15.5365 (-3.57445 7.63266)
R2^2/D10^2 : 5.85105E-02 (-0.0474153 0.12998)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 47.65 using 59 PHA bins.
# Reduced chi-squared = 0.8663 for 55 degrees of freedom
# Null hypothesis probability = 7.487219e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 8.142e-08 3.225e-08
25- 50 9.720e-08 3.093e-08
50-150 9.404e-08 5.102e-08
15-150 2.727e-07 7.995e-08
Peak spectrum fit
Power-law model
Time interval is from -0.072 sec. to 0.928 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.18487 ( -0.123834 0.12825 )
Norm@50keV : 1.95132E-02 ( -0.00164918 0.0016262 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 42.69 using 59 PHA bins.
# Reduced chi-squared = 0.7489 for 57 degrees of freedom
# Null hypothesis probability = 9.205282e-01
Photon flux (15-150 keV) in 1 sec: 3.20501 ( -0.21994 0.220196 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.83085e-07 ( -1.36701e-08 1.37778e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.072 sec. to 0.928 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.43186 ( -0.669555 0.519357 )
Epeak [keV] : 31.1084 ( )
Norm@50keV : 5.33309E-02 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 37.39 using 59 PHA bins.
# Reduced chi-squared = 0.6678 for 56 degrees of freedom
# Null hypothesis probability = 9.736423e-01
Photon flux (15-150 keV) in 1 sec: 3.11402 ( -0.23038 0.23017 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.71775e-07 ( -1.5486e-08 1.5943e-08 ) ergs/cm2
Band function
Time interval is from -0.072 sec. to 0.928 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.877164 ( -1.18216 0.65658 )
beta : -2.60621 ( 2.57605 0.340602 )
Epeak [keV] : 31.1541 ( -7.78864 7.36456 )
Norm@50keV : 0.125086 ( -0.0705784 3324.8 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 35.91 using 59 PHA bins.
# Reduced chi-squared = 0.6530 for 55 degrees of freedom
# Null hypothesis probability = 9.783694e-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] : 9.38238 (-0.687298 0.736207)
R^2/D10^2 : 1.86109 (-0.489241 0.665325)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 71.26 using 59 PHA bins.
# Reduced chi-squared = 1.250 for 57 degrees of freedom
# Null hypothesis probability = 9.690813e-02
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 3.254e-08 3.650e-09
25- 50 7.372e-08 5.840e-09
50-150 3.190e-08 5.980e-09
15-150 1.382e-07 1.080e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 50.9526 (-8.25838 10.9958)
Norm : 17.9121 (-2.02955 2.46073)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 37.40 using 59 PHA bins.
# Reduced chi-squared = 0.6562 for 57 degrees of freedom
# Null hypothesis probability = 9.791906e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 4.398e-08 3.910e-09
25- 50 6.359e-08 4.610e-09
50-150 6.285e-08 1.098e-08
15-150 1.704e-07 1.370e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 5.86063 (-1.59253 1.78073)
R1^2/D10^2 : 8.32673 (-4.70291 11.204)
kT2 [keV] : 16.9832 (-4.4041 14.2773)
R2^2/D10^2 : 0.109905 (-0.0975929 0.327442)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 39.56 using 59 PHA bins.
# Reduced chi-squared = 0.7193 for 55 degrees of freedom
# Null hypothesis probability = 9.420979e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 4.317e-08 1.350e-08
25- 50 6.332e-08 1.427e-08
50-150 6.166e-08 3.135e-08
15-150 1.682e-07 5.026e-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: 2.29308 ( -0.150109 0.157243 )
Norm@50keV : 6.73011E-03 ( -0.000698384 0.000686575 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 46.57 using 59 PHA bins.
# Reduced chi-squared = 0.8170 for 57 degrees of freedom
# Null hypothesis probability = 8.365582e-01
Photon flux (15-150 keV) in 4.604 sec: 1.17164 ( -0.0877726 0.087857 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.95727e-07 ( -2.52081e-08 2.55681e-08 ) ergs/cm2
Cutoff power-law model
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.94088 ( -0.704285 0.0567269 )
Epeak [keV] : 6.66037 ( -5.53853 24.5235 )
Norm@50keV : 1.08914E-02 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 45.59 using 59 PHA bins.
# Reduced chi-squared = 0.8142 for 56 degrees of freedom
# Null hypothesis probability = 8.383667e-01
Photon flux (15-150 keV) in 4.604 sec: 1.15343 ( -0.09299 0.09275 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.85124e-07 ( -3.0159e-08 3.07902e-08 ) ergs/cm2
Band function
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.76941 ( 1.77345 1.77345 )
beta : -2.58869 ( 2.58823 0.405422 )
Epeak [keV] : 16.3567 ( -16.04 11.9424 )
Norm@50keV : 1.40890E-02 ( -0.00497673 2547.94 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 45.28 using 59 PHA bins.
# Reduced chi-squared = 0.8232 for 55 degrees of freedom
# Null hypothesis probability = 8.221186e-01
Photon flux (15-150 keV) in 4.604 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) = 9.54e-08
S(50-100 keV) = 7.78e-08
T90 vs. Hardness ratio plot
T90 = 3.47999995946884 sec.
Hardness ratio (energy fluence ratio) = 0.815514
Color vs. Color plot
Count Ratio (25-50 keV) / (15-25 keV) = 0.908806
Count Ratio (50-100 keV) / (15-25 keV) = 0.343345
Mask shadow pattern
IMX = 2.256228773123946E-01, IMY = -3.133946757620175E-01
TIME vs. PHA plot around the trigger time
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 0.256000
TIME vs. DetID plot around the trigger time
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 0.256000
100 us light curve (15-350 keV)
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 0.256000
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:
-213.003410 -1.376000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
254.2679 35.2157 0.0 37.4 100.7 -0.9559 -2.1 12.0 Her X-1
263.0190 -24.7624 7.5 55.0 14.9 -1.4704 -1.5 1.1 GX 1+4
268.4445 -1.6141 3.4 33.9 30.8 0.7566 3.4 10.7 SW J1753.5-0127
270.2936 -25.0673 7.6 51.8 7.7 0.7490 1.5 0.9 GX 5-1
270.2057 -25.7514 3.6 52.4 7.4 -1.5985 -3.1 5.3 GRS 1758-258
273.9347 -13.8500 0.0 40.3 11.1 -0.2765 -1.0 11.9 GX 17+2
275.9884 -30.4635 5.4 54.6 -0.8 1.1803 2.1 6.7 H1820-303
284.8979 -24.9464 8.2 47.1 -8.6 0.4412 1.4 7.7 HT1900.1-2455
288.7939 10.9539 0.6 11.5 6.8 3.0394 19.0 0.6 GRS 1915+105
299.5945 35.1993 0.5 14.8 178.2 3.5428 22.6 0.2 Cyg X-1
308.0536 40.9868 1.0 23.0 -172.1 1.9899 11.4 3.3 Cyg X-3
326.0108 38.3713 8.2 32.3 -149.0 0.2851 1.4 8.1 Cyg X-2
257.6417 1.8935 2.2 40.4 46.3 2.0177 5.2 ------ UNKNOWN
335.8714 69.2453 2.9 54.2 177.0 2.3759 4.0 ------ UNKNOWN
301.1382 -35.9161 2.6 57.6 -26.8 4.5134 4.5 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image:
-1.376000 3.228000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
254.5222 35.4194 5.3 37.2 101.1 0.1456 2.2 5.6 Her X-1
262.9398 -24.7226 7.1 55.0 15.0 0.2222 1.6 4.0 GX 1+4
268.3288 -1.4560 15.7 33.9 31.1 0.0274 0.7 2.4 SW J1753.5-0127
270.3614 -25.1565 4.3 51.8 7.6 0.1882 2.7 6.3 GX 5-1
270.4018 -25.6309 7.1 52.2 7.3 0.1193 1.6 8.6 GRS 1758-258
274.0671 -13.8998 7.9 40.3 10.9 -0.0512 -1.5 8.9 GX 17+2
276.0262 -30.3837 7.5 54.5 -0.8 0.1295 1.5 5.3 H1820-303
284.8714 -25.0297 5.1 47.1 -8.6 0.1018 2.3 11.1 HT1900.1-2455
288.6139 10.8664 4.4 11.6 7.5 -0.0540 -2.6 11.9 GRS 1915+105
299.4882 35.3784 4.5 14.9 177.6 0.0550 2.5 11.7 Cyg X-1
308.2946 41.0482 54.2 23.2 -171.8 0.0051 0.2 10.1 Cyg X-3
326.1654 38.1989 7.8 32.4 -148.7 0.0421 1.5 7.4 Cyg X-2
267.6455 12.0441 3.1 26.9 54.2 0.1185 3.8 ------ UNKNOWN
273.0751 14.2966 0.5 21.1 54.2 0.6593 25.7 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image:
172.796610 962.737000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
264.7465 -44.4502 20.3 54.1 174.1 0.8894 0.6 0.2 4U 1735-44
340.7290 -71.9245 3.0 10.8 -167.5 1.5225 3.8 ------ UNKNOWN
57.8012 -41.8056 2.9 36.3 -4.2 2.0560 3.9 ------ UNKNOWN
47.4408 -28.8214 2.2 46.4 -22.0 4.0813 5.2 ------ UNKNOWN
9.9157 -29.7487 3.9 42.4 -69.0 6.7583 3.0 ------ UNKNOWN
320.5897 -33.3836 3.0 48.0 -128.9 7.0303 3.8 ------ UNKNOWN
Plot creation:
Sat May 30 20:06:13 EDT 2015