## omega_lambda parameter in CAMB-1.3.2

Use of Cobaya. camb, CLASS, cosmomc, compilers, etc.
Dournac Fabien
Posts: 65
Joined: May 18 2019
Affiliation: IRAP
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### omega_lambda parameter in CAMB-1.3.2

Hello,

I just want to check if the parameter omega_lambda is still taken into account into the compute of power spectra in last CAMB-1.3.2 version.

Indeed, we can't use any more the option "use_physical = F" as it was the case in the previous version CAMB-0.1.7 on which I was working, and so we only work with the following Omega ("little" Omega) :

ombh2 = 0.0226
omch2 = 0.112
omnuh2 = 0.00064
omk = 0
hubble = 70

As you can see, there is no omega_lambda present : is this parameter deduced from "omega_lambda = 1 - sum_i omega_i/h^2" ?

Maybe there is a little "omega_lambda" defined somewhere but I didn't see it in the default params_base.ini , Could someone double check it ?

Regards
Last edited by Dournac Fabien on January 30 2022, edited 1 time in total.

Antony Lewis
Posts: 1765
Joined: September 23 2004
Affiliation: University of Sussex
Contact:

### Re: omega_lambda parameter in CAMB-1.3.2

Yes, it is deduced

Dournac Fabien
Posts: 65
Joined: May 18 2019
Affiliation: IRAP
Contact:

### Re: omega_lambda parameter in CAMB-1.3.2

ok, thanks and what about the parameter "omk" :

Is it equal to :

?

with

?

Antony Lewis
Posts: 1765
Joined: September 23 2004
Affiliation: University of Sussex
Contact:

### Re: omega_lambda parameter in CAMB-1.3.2

omk is just $\Omega_K$