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
250.1661 68.2247 0.0074 30.8365 -168.0504 2.2375506 25.994 TRIG_00557354
Foreground time interval of the image:
-0.444 36.469 (delta_t = 36.913 [sec])
Background time interval of the image:
-330.931 -315.946 (delta_t = 14.986 [sec])
-239.632 -0.444 (delta_t = 239.188 [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 -0.444 sec. to 95.768 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.62848 ( -0.142904 0.144571 )
Norm@50keV : 1.71904E-03 ( -0.000139227 0.000137782 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.41 using 59 PHA bins.
# Reduced chi-squared = 0.9896 for 57 degrees of freedom
# Null hypothesis probability = 4.973221e-01
Photon flux (15-150 keV) in 96.21 sec: 0.222897 ( -0.0171512 0.0171897 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.54165e-06 ( -1.34041e-07 1.35361e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.444 sec. to 95.768 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.39051 ( -0.153593 0.138413 )
Epeak [keV] : 137.740 ( -9999.35 -9999.36 )
Norm@50keV : 7.00505E-04 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.46 using 59 PHA bins.
# Reduced chi-squared = 0.9725 for 56 degrees of freedom
# Null hypothesis probability = 5.334147e-01
Photon flux (15-150 keV) in 96.21 sec: 0.223272 ( -0.01772 0.016845 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.54288e-06 ( -1.3531e-07 1.27873e-07 ) ergs/cm2
Band function
Time interval is from -0.444 sec. to 95.768 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 4.84248 ( -4.84248 -4.84248 )
beta : -1.65812 ( -0.157968 0.151116 )
Epeak [keV] : 20.0077 ( -20.0077 4.89659 )
Norm@50keV : 615.887 ( -46.259 1.09507e+06 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.14 using 59 PHA bins.
# Reduced chi-squared = 1.021 for 55 degrees of freedom
# Null hypothesis probability = 4.318186e-01
Photon flux (15-150 keV) in 96.21 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] : 12.2522 ( )
R^2/D10^2 : 4.82806E-02 ( )
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 119.12 using 59 PHA bins.
# Reduced chi-squared = 2.0899 for 57 degrees of freedom
# Null hypothesis probability = 2.781312e-06
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.477e-07 2.136e-08
25- 50 4.762e-07 5.215e-08
50-150 4.358e-07 8.673e-08
15-150 1.060e-06 1.091e-07
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 180.090 (-62.9034 -178.727)
Norm : 0.898193 (-0.0724232 0.087131)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 60.57 using 59 PHA bins.
# Reduced chi-squared = 1.063 for 57 degrees of freedom
# Null hypothesis probability = 3.483481e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.179e-07 4.435e-08
25- 50 4.140e-07 1.430e-07
50-150 8.768e-07 4.463e-07
15-150 1.509e-06 7.038e-07
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 7.71139 (-1.17426 1.2403)
R1^2/D10^2 : 0.212801 (-0.0870975 0.170161)
kT2 [keV] : 46.6966 (-15.4531 53.2469)
R2^2/D10^2 : 4.58943E-04 (-0.000381427 0.000995781)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 52.24 using 59 PHA bins.
# Reduced chi-squared = 0.9498 for 55 degrees of freedom
# Null hypothesis probability = 5.808759e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.250e-07 4.320e-08
25- 50 4.297e-07 8.404e-08
50-150 9.799e-07 4.704e-07
15-150 1.635e-06 5.626e-07
Peak spectrum fit
Power-law model
Time interval is from 14.392 sec. to 15.392 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.31784 ( -0.427064 0.409536 )
Norm@50keV : 6.40191E-03 ( -0.00143698 0.00143343 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.41 using 59 PHA bins.
# Reduced chi-squared = 1.025 for 57 degrees of freedom
# Null hypothesis probability = 4.233681e-01
Photon flux (15-150 keV) in 1 sec: 0.766330 ( -0.176306 0.176986 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.29917e-08 ( -1.56844e-08 1.59809e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 14.392 sec. to 15.392 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.32660 ( -0.440716 0.401152 )
Epeak [keV] : 9999.35 ( -9999.36 -9999.36 )
Norm@50keV : 6.39253E-03 ( -0.00144154 0.0218949 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.42 using 59 PHA bins.
# Reduced chi-squared = 1.043 for 56 degrees of freedom
# Null hypothesis probability = 3.865780e-01
Photon flux (15-150 keV) in 1 sec: 0.768816 ( -0.177583 0.174404 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.31138e-08 ( -1.58622e-08 1.55112e-08 ) ergs/cm2
Band function
Time interval is from 14.392 sec. to 15.392 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 4.64018 ( -4.64018 -4.64018 )
beta : -1.65480 ( -0.809592 0.602277 )
Epeak [keV] : 34.6587 ( -34.6587 39.5019 )
Norm@50keV : 53.1275 ( -11.7918 3.34417e+06 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.82 using 59 PHA bins.
# Reduced chi-squared = 1.051 for 55 degrees of freedom
# Null hypothesis probability = 3.715239e-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] : 13.5036 (-3.44874 5.91816)
R^2/D10^2 : 0.125556 (-0.0899733 0.232796)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 64.34 using 59 PHA bins.
# Reduced chi-squared = 1.129 for 57 degrees of freedom
# Null hypothesis probability = 2.353304e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 4.849e-09 2.398e-09
25- 50 1.739e-08 8.661e-09
50-150 2.048e-08 1.155e-08
15-150 4.272e-08 1.883e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 199.356 (-100.217 -199.36)
Norm : 3.16667 (-0.714394 0.716187)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.68 using 59 PHA bins.
# Reduced chi-squared = 1.047 for 57 degrees of freedom
# Null hypothesis probability = 3.784026e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 7.885e-09 4.802e-09
25- 50 1.517e-08 9.010e-09
50-150 3.327e-08 1.962e-08
15-150 5.632e-08 3.322e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 9.75282 (-2.31225 2.31707)
R1^2/D10^2 : 0.331178 (-0.194181 0.342279)
kT2 [keV] : 198.933 (-199.072 -199.072)
R2^2/D10^2 : 1.34744E-04 (-5.8605e-05 0.00155105)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 53.32 using 59 PHA bins.
# Reduced chi-squared = 0.9695 for 55 degrees of freedom
# Null hypothesis probability = 5.388819e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 6.530e-09 3.783e-09
25- 50 1.671e-08 9.475e-09
50-150 4.298e-08 9.350e-09
15-150 6.622e-08 2.209e-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: 1.39971 ( -0.114794 0.114439 )
Norm@50keV : 3.86762E-03 ( -0.000241733 0.000241359 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 47.23 using 59 PHA bins.
# Reduced chi-squared = 0.8286 for 57 degrees of freedom
# Null hypothesis probability = 8.185254e-01
Photon flux (15-150 keV) in 36.91 sec: 0.470973 ( -0.0305355 0.0306144 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.37946e-06 ( -9.50038e-08 9.54843e-08 ) ergs/cm2
Cutoff power-law model
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.40044 ( -0.28783 0.112518 )
Epeak [keV] : 9999.26 ( -9999.35 -9999.35 )
Norm@50keV : 3.87559E-03 ( -0.000241856 0.00139296 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 47.25 using 59 PHA bins.
# Reduced chi-squared = 0.8438 for 56 degrees of freedom
# Null hypothesis probability = 7.910390e-01
Photon flux (15-150 keV) in 36.91 sec: 0.470782 ( -0.030484 0.030588 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.37859e-06 ( -9.14371e-08 9.41463e-08 ) ergs/cm2
Band function
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 3.95618 ( -3.95691 -3.95691 )
beta : -1.42118 ( -0.123719 0.121413 )
Epeak [keV] : 22.2146 ( -22.2134 107 )
Norm@50keV : 114.378 ( -114.419 259715 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 46.82 using 59 PHA bins.
# Reduced chi-squared = 0.8512 for 55 degrees of freedom
# Null hypothesis probability = 7.758098e-01
Photon flux (15-150 keV) in 36.91 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) = 4.05e-07
S(50-100 keV) = 5.24e-07
T90 vs. Hardness ratio plot
T90 = 76.2839999198914 sec.
Hardness ratio (energy fluence ratio) = 1.29383
Color vs. Color plot
Count Ratio (25-50 keV) / (15-25 keV) = 1.21011
Count Ratio (50-100 keV) / (15-25 keV) = 0.758603
Mask shadow pattern
IMX = -5.840468575128441E-01, IMY = 1.236059627389259E-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:
-330.931340 -315.945500
-239.632000 -0.444000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
254.6033 35.4564 4.8 40.7 136.4 1.4890 2.4 9.9 Her X-1
299.6290 35.2064 1.7 18.3 70.9 1.7270 6.7 1.9 Cyg X-1
308.0904 40.9532 1.0 11.6 48.0 2.7311 11.7 0.9 Cyg X-3
326.1694 38.3489 7.3 19.1 0.2 0.3194 1.6 1.6 Cyg X-2
278.1197 48.4392 2.2 19.1 138.9 1.1697 5.3 ------ UNKNOWN
351.1074 42.2062 2.9 30.6 -38.3 1.0776 3.9 ------ UNKNOWN
179.5616 74.9184 2.4 48.0 -146.4 2.5340 4.8 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image:
-0.444000 36.468590
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
254.3079 35.2292 0.0 41.0 136.4 0.5892 2.5 10.0 Her X-1
299.6766 35.3340 3.3 18.2 70.9 -0.3213 -3.5 9.0 Cyg X-1
308.0717 41.0419 5.8 11.5 48.0 -0.1586 -2.0 5.6 Cyg X-3
325.9866 38.4012 21.5 19.0 0.5 -0.0427 -0.5 9.9 Cyg X-2
219.7454 60.3890 2.2 45.5 -174.3 0.7381 5.2 ------ UNKNOWN
250.1662 68.2247 0.4 30.8 -168.1 2.2372 26.0 ------ UNKNOWN
352.7754 26.7998 2.5 42.2 -20.7 0.5280 4.6 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image:
88.468600 238.460700
239.368000 450.568620
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
254.6122 35.3444 5.9 33.0 85.6 1.1820 1.9 7.6 Her X-1
299.6877 35.1268 6.6 43.0 26.5 0.9544 1.8 6.6 Cyg X-1
308.1110 40.9460 1.4 40.8 13.7 3.6155 8.2 0.4 Cyg X-3
326.0442 38.3572 7.4 49.7 -1.6 0.8394 1.6 6.4 Cyg X-2
176.4744 32.3259 4.5 54.2 -179.2 2.7179 2.6 ------ UNKNOWN
140.5822 50.7846 2.9 50.1 -138.5 4.8375 4.0 ------ UNKNOWN
23.8928 62.8774 3.1 44.8 -59.8 4.9401 3.8 ------ UNKNOWN
71.4606 70.9739 3.8 40.8 -88.3 4.2438 3.1 ------ UNKNOWN
Plot creation:
Sat May 30 16:39:12 EDT 2015