ACTPol DR4 CMB Power Spectrum Likelihood

This is the Data Release 4 (DR4) CMB power spectrum likelihood measured by the Atacama Cosmology Telescope (ACT), from the 2013–2016 survey covering >15,000 sq. deg. This spectrum has already been marginalized over SZ and foreground emission. The polarization efficiency is the only nuisance parameter required to be sampled. It is based on the WMAP and ACT team's likelihood software.

Cite: Aiola et al. 2020, Choi et al. 2020. This package is based off of the Fortran implementation written by Erminia Calabrese and Jo Dunkley. Thanks to Tim Morton for helping interface with Cobaya, and special thanks to Leander Thiele for finding a bug in the Monte Python 3 wrapper.

<img src="https://act.princeton.edu/sites/act/files/styles/panopoly_image_original/public/media/angelapano.jpg" alt="panoramic image"/>

Installation

To install, clone this repository and install it using pip.

git clone https://github.com/ACTCollaboration/pyactlike
cd pyactlike
pip install . --user

Usage

This package can be called standalone or with Cobaya. For experimental MontePython support, see the montepython3/ directory in this repository. If you are using a Cobaya version < 2.1.0 (the current stable branch), please see the example Jupyter notebook in notebooks/Example for Cobaya (stable).ipynb.

If you are on Cobaya 2.1.0 (currently the devel branch), using the likelihood is as easy as including it in your YAML or configuration dict. There's one nuisance parameter, the polarization efficiency yp2.

likelihood:
    pyactlike.ACTPol_lite_DR4:

params:   
    yp2:
        prior:
            min: 0.5
            max: 1.5     

We provide additional likelihood configurations for common uses,

• pyactlike.ACTPol_lite_DR4_for_combining_with_Planck for TT,TE,EE excluding the large scale ACT temperature
• pyactlike.ACTPol_lite_DR4_onlyTT for restricting only to TT
• pyactlike.ACTPol_lite_DR4_onlyTE for restricting only to TE
• pyactlike.ACTPol_lite_DR4_onlyEE for restricting only to EE

Tests

Run pytest in the repository base directory run the tests.