Magnetic Fields Studies in the Next Decade: EAO Submillimetre Futures White Paper Series, 2019

TL;DR

This paper discusses the development of a new submillimetre camera for the JCMT that will significantly advance the study of magnetic fields in various astrophysical environments through wide-area polarization mapping.

Contribution

It introduces a novel 850μm MKID-based camera with polarization capabilities, enabling comprehensive magnetic field studies across diverse cosmic objects and environments.

Findings

Enables wide-area polarization mapping at 14'' resolution.

Facilitates studies of magnetic fields in star formation, galaxies, and AGN.

Potential upgrade to 450μm for spectral index analysis.

Abstract

Magnetic fields are ubiquitous in our Universe, but remain poorly understood in many branches of astrophysics. A key tool for inferring astrophysical magnetic field properties is dust emission polarimetry. The James Clerk Maxwell Telescope (JCMT) is planning a new 850$\mu$m camera consisting of an array of 7272 paired Microwave Kinetic Inductance Detectors (MKIDs), which will inherently acquire linear polarization information. The camera will allow wide-area polarization mapping of dust emission at 14$^{\prime\prime}$-resolution, allowing magnetic field properties to be studied in a wide range of environments, including all stages of the star formation process, Asymptotic Giant Branch stellar envelopes and planetary nebula, external galaxies including starburst galaxies and analogues for the Milky Way, and the environments of active galactic nuclei (AGN). Time domain studies of AGN and protostellar polarization variability will also become practicable. Studies of the polarization properties of the interstellar medium will also allow detailed investigation of dust grain properties and physics. These investigations would benefit from a potential future upgrade adding 450$\mu$m capability to the camera, which would allow inference of spectral indices for polarized dust emission in a range of environments. The enhanced mapping speed and polarization capabilities of the new camera will transform the JCMT into a true submillimetre polarization survey instrument, offering the potential to revolutionize our understanding of magnetic fields in the cold Universe.