Pklin vs NL - Githubissues

lesgourg / class_public

Public repository of the Cosmic Linear Anisotropy Solving System (master for the most recent version of the standard code; GW_CLASS to include Cosmic Gravitational Wave Background anisotropies; classnet branch for acceleration with neutral networks; ExoCLASS branch for exotic energy injection; class_matter branch for FFTlog)

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Pklin vs NL #122

Open plaszczy opened 7 years ago

plaszczy commented 7 years ago

hi, I am getting a close look at P(k) w/o non linearity (halofit). I want to compare the NL spectrum to the one obtained with CosmicEmu (CE) So I choose a set of parameters (without neutrinos for the moment since it is not yet clear to me how CE treats them, runs class to determine sigma_8 (which is a needed input to CE) and compare both. Not that CE does not include separately Plin so I use the CLASS one.

plaszczy commented 7 years ago

so here is the comparison plot (again Pklin comes from class on both curves) pkclass.pdf this raises several questions:

class plot: the transition between NL and lin is rather brutal: is there a way to smooth that?
does it make sense that PNL<Plin around k=2e-2?
any idea why CE is so different?

thanks, cheers stephane