Lyman break analogues (LBAs) are local galaxies selected to match a more
distant (usually z~3) galaxy population in luminosity, UV-spectral slope and
physical characteristics, and so provide an accessible laboratory for exploring
their properties. However, as the Lyman break technique is extended to higher
redshifts, it has become clear that the Lyman break galaxies (LBGs) at z~3 are
more massive, luminous, redder, more extended and at higher metallicities than
their z~5 counterparts. Thus extrapolations from the existing LBA samples
(which match z=3 properties) have limited value for characterising z>5
galaxies, or inferring properties unobservable at high redshift. We present a
new pilot sample of twenty-one compact star forming galaxies in the local
(0.05<z<0.25) Universe, which are tuned to match the luminosities and star
formation volume densities observed in z>~5 LBGs. Analysis of optical emission
line indices suggests that these sources have typical metallicities of a few
tenths Solar (again, consistent with the distant population). We also present
radio continuum observations of a subset of this sample (13 sources) and
determine that their radio fluxes are consistent with those inferred from the
ultraviolet, precluding the presence of a heavily obscured AGN or significant
dusty star formation.Comment: 13 pages, MNRAS accepte