pith. sign in

arxiv: 1704.00215 · v3 · pith:7YD6AXMXnew · submitted 2017-04-01 · 🌌 astro-ph.CO · astro-ph.IM

A New Limit on CMB Circular Polarization from SPIDER

classification 🌌 astro-ph.CO astro-ph.IM
keywords polarizationcircularspiderlimitconstraintsflightlimitslinear
0
0 comments X
read the original abstract

We present a new upper limit on CMB circular polarization from the 2015 flight of SPIDER, a balloon-borne telescope designed to search for $B$-mode linear polarization from cosmic inflation. Although the level of circular polarization in the CMB is predicted to be very small, experimental limits provide a valuable test of the underlying models. By exploiting the non-zero circular-to-linear polarization coupling of the HWP polarization modulators, data from SPIDER's 2015 Antarctic flight provide a constraint on Stokes $V$ at 95 and 150 GHz from $33<\ell<307$. No other limits exist over this full range of angular scales, and SPIDER improves upon the previous limit by several orders of magnitude, providing 95% C.L. constraints on $\ell (\ell+1)C_{\ell}^{VV}/(2\pi)$ ranging from 141 $\mu K ^2$ to 255 $\mu K ^2$ at 150 GHz for a thermal CMB spectrum. As linear CMB polarization experiments become increasingly sensitive, the techniques described in this paper can be applied to obtain even stronger constraints on circular polarization.

This paper has not been read by Pith yet.

discussion (0)

Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.

Forward citations

Cited by 1 Pith paper

Reviewed papers in the Pith corpus that reference this work. Sorted by Pith novelty score.

  1. Probing Axion-Photon conversion via circular polarization imprints in the CMB $V$-mode observations

    astro-ph.CO 2025-10 unverdicted novelty 6.0

    Proposes that axion-photon conversion in pre-CMB helical magnetic fields imprints detectable V-mode polarization in the CMB, allowing CLASS 40 GHz observations to constrain ALP masses 10^{-10} to 10^{-8} eV and their ...