Significant differences between Matter Power spectra of CAMB and EFTCAMB

[Dournac Fabien]

Hi,

I have generated matter power spectra of CAMB (with C.P.L for Dark energy e.o.s and with fiducial values w0=-1 and wa=0) and EFTCAMB to compare them. For EFTCAMB, I took the option EFTflag = 3 and DesignerEFTmodel=1 ( f(R) model ).

Here the both matter power spectra ( at z=0.001) :



As you can see, for large scales, they are similar but at small scales, the EFTCAMB with my options is pretty higher than CAMB version.

Is this difference normal ? What is the cause of this discrepancy ?

Any remark / suggestion / tracks are welcome.