Mass-metallicity relation of zCOSMOS galaxies at z ≈ 0.7, its dependence on star formation rate, and the existence of massive low-metallicity galaxies

摘要

Aims. The knowledge of the number and physical nature of low-metallicity massive galaxies is crucial for determining and interpreting the mass-metallicity relation (MZR). Methods. Using VLT-ISAAC near-infrared (NIR) spectroscopy of 39 zCOSMOS 0.5