The FGF+ Page

The following are updates to the "Compton Reflection" calculations presented in George & Fabian (1991), and hence updates to the "FGF page". Some are based on FGF calculations but not published, others include work presented by others (as noted).

EW of the Kalpha Lines

The following are the equivalent widths (EW) (in eV) of the Kalpha lines as measured against the reflected continuum. The geometry is a centrally illuminated (neutral, infinitely thick) slab subtending 2pi sterad assuming cosmic abundance viewed "face-on". The illuminating spectrum is a Gamma=1.9 powerlaw. Also given are the corresponding ratio of the Normalization of the Kalpha line to the Normalization of the pexrav model in xspec (for the case where pexrav parameter rel_refl=-1).

Element EW (eV) Rel.Norm

O 820 2.25x10^-3

Ne 470 6.00x10^-3

Mg 175 2.50x10^-4

Si 265 4.54x10^-4

S 210 4.05x10^-4

Ar 62 1.36x10^-4

Ca 80 2.03x10^-4

Cr 36 1.18x10^-4

Fe 1320 4.75x10^-3

Ni 120 2.40x10^-4

Some of these values were extracted from Matt, Fabian & Reynolds (1997 - see Compton Reflection Papers).

Index dependence of Rel.Norm

The following gives the ratio of the (pexrav) Rel.Norm of the Fe Kalpha line at some value of Gamma to that at Gamm=1.9. A face-on slab,cosmic abundance etc (as above) is assumed.

1.3 1.5 1.7 1.9 2.1 2.3

4.063 2.589 1.613 1.000 0.636 0.404

The ratio can be adequately parameterized by

Ratio = 9.66 x (Gamma)^-2.80 - 0.56

The FGF+ Page

EW of the Kalpha Lines

Index dependence of Rel.Norm

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