CAMB: equations_PPF.f90 question
Posted: December 03 2015
Hi,
I'm working on a project where I need to modify the parameterisation w(a) = w0 + wa * (1-a) from the equations_PPF.f90 file used in CAMB and CosmoMC.
I can tell that I definitely need to modify line 98:
But then in line 143 we have:
I'm unsure exactly what this equation is. To me it looks very close to the behaviour of dark energy density which is:
(See e.g. Appendix A of King 2014, http://arxiv.org/abs/1311.2356)
So, in summary - what role does line 143 of equations_PPF.f90 play in CAMB, and if I want to modify the w(a) = w0 + wa * (1-a) parameterisation do I also need to modify line 143 and not just line 98?
Thank you!
- Per
I'm working on a project where I need to modify the parameterisation w(a) = w0 + wa * (1-a) from the equations_PPF.f90 file used in CAMB and CosmoMC.
I can tell that I definitely need to modify line 98:
Code: Select all
w_de=w_lam+wa_ppf*(1._dl-a)
Code: Select all
grho_de=grhov*a**(1._dl-3.*w_lam-3.*wa_ppf)*exp(-3.*wa_ppf*(1._dl-a))
Code: Select all
f(a) = a**(-3.*(1+w_lam+wa_ppf)) * exp(-3*wa_ppf*(1.-a))
So, in summary - what role does line 143 of equations_PPF.f90 play in CAMB, and if I want to modify the w(a) = w0 + wa * (1-a) parameterisation do I also need to modify line 143 and not just line 98?
Thank you!
- Per