Here are the key parameters for the WHIM simulation:

ISIS model:
fit_fun("tbnew(1)*(powerlaw(1)+ngauss(1))");

The EW were determined from:
(provided by J. Bregman based of Toatao Fang's model)

EW = 10^(1.00175-0.30923*log(1/Z)-0.41225*(log(1/Z))^2)

Ion      lambda/A      

O VIIILa   18.97         
O VIILa    21.60        
O VIILb    17.65      

 Z     0.01     0.10     0.30     0.60    0.90
 EW   0.054    0.738     2.564   5.626   8.910   mA

line centers:  lamda*(1 + Z) 
Line widths:   2.5*(1 + Z) mA ; CAT resolution is 7.2 mA @ 21.6 A

Source:

set_par( "tbnew(1).nH", 0.017, 1 );
set_par("powerlaw(1).PhoIndex",1.046,1,-3.0,3.0);
set_par("powerlaw(1).norm",0.001,1,1e-6,1e2);

F_x = 1.03088e-11 erg/cm2/s