HD93129: Chandra grating spectrum

Alternate wind parameters

9.1687, 9.2297, 9.3143 Angstroms: Mg XI

vinf = 3200
β = 1.0

Mg XI 9.1687 MEG

Mg XI 9.1687 HEG
[9.04:9.43], λo = 9.1687, 9.2297, 9.3143
powerlaw continuum, n=2; norm=2.05e-4
taustar=1.97   +/- (0.91:4.37)
      0.37:5.38 at 90% confidence
Ro=2.41   +/- (1.01:3.71)
G=0.37   +/- (0.22:0.63)
φ-ratio = 147  
norm=1.58e-5 +/- (1.45e-5:1.72e-5)
rejection probability = ???% (C=412.14; N=464)
fit log

Here are the 68%, 90%, and 95% joint confidence limits on taustar and Ro. The filled circle represents the best-fit model, shown as the red histograms on the above plots.

Mg XI 9.1687: joint Ro taustar constraints using MEG and HEG data

Note that the best-fit point is actually a bit off the top of the contour plot.

Note also that the best-fit G value is pretty small. Here's a fit for which we froze G at 0.71, the value expected from atomic physics at the temperature of peak emissivity. (If anything, real, high S/N data tend to show somewhat higher values than this.)


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last modified: 30 January 2011