MeerKAT observations of Procyon at 815.5 MHz

TL;DR

This study used MeerKAT radio observations to search for transient and polarized radio emission from Procyon, setting upper limits on emission and spectral index, but found no significant signals.

Contribution

First detailed MeerKAT radio observations of Procyon, providing upper limits on emission and polarization, and comparing spectral index with past data.

Findings

No significant radio emission detected from Procyon.

Upper limit on circular polarization fraction is 65%.

Spectral index between 815.5 and 8400 MHz is at least 0.26.

Abstract

We have conducted observations of the nearby (11.46 ly) star system Procyon, using MeerKAT's UHF (544-1087 MHz) receivers. We produce full-Stokes time and frequency integrated continuum images, as well as total intensity time series imaging at 8 s cadence, and full-Stokes vector-averaged dynamic spectra from the visibilities in order to search for transient activity such as flaring events. We detect no significant radio emission from the system, and estimate an upper limit on the circular polarisation fraction of 65 per cent (3$\sigma$ confidence level). A comparison with previous VLA observations places a 3$\sigma$ lower limit on the spectral index between 815.5 and 8400 MHz of 0.26, however long-term significant variability over the last 33 years cannot be ruled out without further, regular radio monitoring of the system.