MAGNUS I: A MUSE-DEEP sample of early-type galaxies at intermediate redshift

Abstract

We present a sample of 212 early-type galaxies (ETGs) at redshifts $0.25<z<0.75$. We combine deep integral-field spectroscopy from the MUSE-DEEP survey with high-resolution HST imaging to study the structure, kinematics, and stellar populations of these galaxies. We measure spatially resolved stellar kinematics and use the specific angular momentum proxy, $\hat{I}{»}_R$, to classify galaxies into fast and slow rotators. We find a slow rotator fraction consistent with local Universe samples, suggesting little evolution in the massive ETG population since $z\sim 1$. The kinematic and photometric axes of fast rotators are generally well-aligned, similar to their local counterparts. We find that global stellar population properties, such as age, metallicity, and mass-to-light ratio ($M_{\ast }/L$), correlate strongly with the central velocity dispersion ($\ddot{I}{ƒ}_{\mathrm{e}}$), following trends established for local ETGs. Slow rotators are typically more massive, have higher $\ddot{I}{ƒ}_{\mathrm{e}}$, and are more metal-rich than fast rotators. Our findings indicate that the fundamental structural, kinematic, and stellar population scaling relations of massive ETGs were already in place by $z\sim 0.75$, suggesting their evolutionary pathways have remained stable over the last $\sim 7$ Gyr.

Submitted to ApJ