CosmoCoffee

Luke Hart · Posted: July 26 2017

Dear Antony and co,

Firstly, I'd just like to say thanks for the availability of the ISW and Doppler components of the CMB spectrum individually made available via the outputs routine in equations.f90.

My question however is how do we isolate the OSW effect specifically. We can isolate the ISW (even the early and late components) however, isolating the gravitational redshift component is proving difficult, maybe due to the formalism within equations.f90? I'm not sure?

Any help would be awesome thanks

Luke

Antony Lewis · Posted: July 26 2017

How do you define OSW?

You can try the scal_eqs branch, which makes it easy to get different terms from python. e.g. see the plots in the sample notebook at

http://nbviewer.jupyter.org/github/cmbant/CAMB/blob/scal_eqs/pycamb/docs/ScalEqs.ipynb

Luke Hart · Posted: August 01 2017

I'm referencing the evaluation of the

Θ l

components in the CMB spectrum. So I may have got this wrong but when I check the Dodelson, I've found the first component of $\Theta_l(k,\eta_0)=\int^{\eta_0}_0d\eta g(\eta) \left[\Theta_0(k,\eta)+\Psi(k,\eta)\right]\,j_l$ with the Bessel weighting.

I'm trying to isolate this term in an effort to recreate the figure from one of Anthony Challinor's lecture courses where he isolates each component of the CMB spectra.

It seems a bit difficult to isolate this component in the outputs module of equations.f90

Thanks Antony

Luke