The VANDELS survey: The relation between the UV continuum slope and stellar metallicity in star-forming galaxies at <i>z</i> ∼ 3

The estimate of stellar metallicities (Z*) high-z galaxies are paramount importance in order to understand the complexity dust effects and reciprocal interrelations among mass, attenuation, age, metallicity. Benefiting from uniquely deep FUV spectra >500 star-forming at redshifts 2<z<5 extracted VANDELS survey stacked bins mass (M*) UV continuum slope (beta), we their Z* photospheric absorption features 1501 1719 Angstrom, which calibrated with Starburst99 models largely unaffected by dust, IMF, nebular or interstellar absorption. Comparing them photometric based spectral slopes range 1250-1750 find that metallicity increases ~0.5 dex beta ~ -2 -1 (1 < A(1600) 3.2), a dependence holds fixed absolute luminosity M(UV) up 10^(9.65) Msun. As result, is fundamental ingredient for properly rescaling corrections on M*. Using same features, analyze mass-metallicity relation (MZR) it consistent previous estimation global fit spectra. Similarly, do not significant evolution between z=2 z=3.5. Finally, our MZR Z*-beta agreement predictions well-studied semi-analytic galaxy formation (SAM), while some tensions observations remain as normalization. exploitation large volume surveys next-generation telescopes physical characterization first billion years Universe.