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arXiv · 2501.16126

E-INSPIRE -- I. Bridging the gap with the local Universe: Stellar population of a statistical sample of ultra-compact massive galaxies at $z<0.3$

John Mills·Chiara Spiniello·Alexey Sergeyev·Crescenzo Tortora·Vladyslav Khramtsov·Giuseppe D'Ago·Michalina Maksymowicz-Maciata·João P. V. Benedetti·Anna Ferré-Mateu·Michele Cappellari·Roger Davies·Johanna Hartke·Charles Rosen
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Abstract

This paper presents the first effort to Extend the Investigation of Stellar Populations In RElics (E-INSPIRE). We present a catalogue of 430 spectroscopically-confirmed ultra-compact massive galaxies (UCMGs) from the Sloan Digital Sky Survey at redshifts $0.01 25\%$) of their stellar mass at $z<2$. We confirm that an efficient method of finding relics is to select UCMGs with large velocity dispersion values but we believe that the most efficient way is to select high velocity dispersion objects that also have super-solar metallicities and high [Mg/Fe].

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John Mills, Chiara Spiniello, Alexey Sergeyev, Crescenzo Tortora, Vladyslav Khramtsov, Giuseppe D'Ago, Michalina Maksymowicz-Maciata, João P. V. Benedetti, Anna Ferré-Mateu, Michele Cappellari, Roger Davies, Johanna Hartke, Charles Rosen. 2025-01-27. E-INSPIRE -- I. Bridging the gap with the local Universe: Stellar population of a statistical sample of ultra-compact massive galaxies at $z<0.3$. https://arxiv.org/abs/2501.16126

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