A Search for Scalar Chameleons with ADMX

TL;DR

This paper reports the first experimental search for scalar chameleon fields using the ADMX microwave cavity, setting new limits on their coupling to photons and exploring their potential role in dark energy.

Contribution

It introduces the first search for scalar chameleons with ADMX, providing new constraints on their photon coupling in a specific mass range.

Findings

Set new limits on scalar chameleon-photon coupling.

Excluded coupling values between 2×10^9 and 5×10^14.

Focused on effective chameleon masses around 1.9515 micro-eV.

Abstract

Scalar fields with a "chameleon" property, in which the effective particle mass is a function of its local environment, are common to many theories beyond the standard model and could be responsible for dark energy. If these fields couple weakly to the photon, they could be detectable through the "afterglow" effect of photon-chameleon-photon transitions. The ADMX experiment was used in the first chameleon search with a microwave cavity to set a new limit on scalar chameleon-photon coupling excluding values between 2*10^9 and 5*10^14 for effective chameleon masses between 1.9510 and 1.9525 micro-eV.