21 new long-term variables in the GX 339-4 field: two years of MeerKAT
  monitoring
  We present 21 new long-term variable radio sources found commensally in two
years of weekly MeerKAT monitoring of the low-mass X-ray binary GX 339-4. The
new sources vary on time scales of weeks to months and have a variety of light
curve shapes and spectral index properties. Three of the new variable sources
are coincident with multi-wavelength counterparts; and one of these is
coincident with an optical source in deep MeerLICHT images. For most sources,
we cannot eliminate refractive scintillation of active galactic nuclei as the
cause of the variability. These new variable sources represent $2.2\pm0.5$ per
cent of the unresolved sources in the field, which is consistent with the 1-2
per cent variability found in past radio variability surveys. However, we
expect to find short-term variable sources in the field as well as these 21 new
long-term variable sources. We present the radio light curves and spectral
index variability of the new variable sources, as well as the absolute
astrometry and matches to coincident sources at other wavelengths.
