Background.c equations for dark matter decay

[astrogirl1]

Hi again,

I have introduced new parameters to the code, which are being read and used by CLASS successfully. The issue that I am running into is I am trying to trigger the following if condition to use the equations with the newly added parameters but it is not working. I am unsure where/how I should define has_dcdm so that the condition is TRUE and the equations are calculated.

I know this because I added a print statement inside the if condition and nothing is printing. I have tried to use this in CLASS on its own (using explanatory.ini and defining values there, even has_dcdm) and also using MontePython, but the posteriors for my variables looks exactly like the input priors.

if (pba->has_dcdm == _TRUE_){ printf("'new_param2' input parameter = %g\n", pba->new_param2); /** - compute dcdm density \f$ \rho' = -3aH \rho - a \Gamma \rho \f$*/ dy[pba->index_bi_rho_dcdm] = -3.*y[pba->index_bi_a]*pvecback[pba->index_bg_H]*y[pba->index_bi_rho_dcdm]- y[pba->index_bi_a]*pba->new_param1*pba->Gamma_dcdm*y[pba->index_bi_rho_dcdm]; }

Thank you for your help! Meera

[lesgourg]

By looking into input.c and background.c you can see what happens:

• If in your list of input parameters, there is either Omega_dcdmdr or omega_dcdmdr, the internal variable pba->Omega0_dcdmdr is set to a non-zero value inside input.c
• Then, if pba->Omega0_dcdmdr has been set to a non-zero value, the internal variable pba->has_dcdm is set to _TRUE_ inside background.c

In conclusion, you are not supposed to pass has_dcdm in your input parameter file, but only Omega_dcdmdr or omega_dcdmdr, as documented in explanatory.ini. All the cosmological parameters understood by CLASS are documented in explanatory.ini, and no other cosmological parameter is understood by CLASS (unless you modify the code yourself).

[astrogirl1]

Yes, this has worked thank you!