We present a new Planck CMB lensing-CMB temperature cross-correlation likelihood that can be used to constrain cosmology via the Integrated Sachs-Wolfe (ISW) effect. CMB lensing is an excellent tracer of ISW, and we use the latest PR4 Planck data maps and lensing reconstruction to produce the first public Planck likelihood to constrain this signal. We demonstrate the likelihood by constraining the CMB background temperature from Planck data alone, where the ISW-lensing cross-correlation is a powerful way to break the geometric degeneracy, substantially improving constraints from the CMB and lensing power spectra alone.
@article{arxiv.2209.07395,
title = {Planck ISW-lensing likelihood and the CMB temperature},
author = {Julien Carron and Antony Lewis and Giulio Fabbian},
journal= {arXiv preprint arXiv:2209.07395},
year = {2022}
}
Comments
Matches version accepted by PRD with minor changes. ISW-lensing and lensing likelihoods available at https://github.com/carronj/planck_PR4_lensing