I'm using CAMB in order to reproduce the results of the following article :
An alternative to the cosmological ``concordance model'' :
http://cdsads.u-strasbg.fr/abs/2003A%26A...412...35B
The authors have managed in getting with a good precision the same angular power spectrum as the LCDM model and the WMAP data, but with an Einstein de Sitter Model ( [tex]\Omega_{\Lambda}=0[/tex] and [tex]\Omega_{m}=1[/tex] ) Here is the fit :
For this, they use in CAMB a broken power law of the fluctuation spectrum in this way :
[tex]
P(k)=\left\{
\begin{array}{ccc}
A_{1}\,k^{n_{1}} & for & k<k_{1} \\
A_{2}\,k^{n_{2}} & for & k \geq k_{1} \\
\end{array}
\right.
[/tex]
with a continuity condition : [tex]A_{1}\,k_{1}^{n_{1}}=A_{2}\,k_{1}^{n_{2}}[/tex]
The above figure has been got with : [tex] h=0.46\,,\, \Omega_{b}\,h^{2}=0.019\,,\,\tau=0.16\,,\,k_{1}=0.0096\,\,Mpc^{-1}\,,\, n_{1}=1.015\,,\,n_{2}=0.806[/tex].
So, my question is : Is this broken power law of fluctutation spectrum already implemented in CAMB ?
If yes, in which subroutine ? in "NonLinear_GetNonLinRatios" subroutine of halofit.f90 ?
if no, where can I implement this in CAMB ?
Have I got to set "do_nonlinear = 1" in "params.ini" ?
Finally, where is specified the above [tex]\tau[/tex] parameter in CAMB sources ?
Thanks in advance.