INSPIRE: INvestigating Stellar Population In RElics -- I. Survey presentation and pilot program

C. Spiniello; C. Tortora; G. D'Ago; L. Coccato; F. La Barbera; A. Ferré-Mateu; N. R. Napolitano; M. Spavone; D. Scognamiglio; M. Arnaboldi; A. Gallazzi; L. Hunt; S. Moehler; M. Radovich; S. Zibetti

doi:10.1051/0004-6361/202038936

arXiv · 2011.05347

INSPIRE: INvestigating Stellar Population In RElics -- I. Survey presentation and pilot program

C. Spiniello·C. Tortora·G. D'Ago·L. Coccato·F. La Barbera·A. Ferré-Mateu·N. R. Napolitano·M. Spavone·D. Scognamiglio·M. Arnaboldi·A. Gallazzi·L. Hunt·S. Moehler·M. Radovich·S. Zibetti

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Abstract

Massive ETGs are thought to form through a two-phase process. At early times, an intense and fast starburst forms blue and disk-dominated galaxies. After quenching, the remaining structures become red, compact and massive, i.e., 'red nuggets'. Then, a time-extended second phase which is dominated by mergers, causes structural evolution and size growth. Given the stochastic nature of mergers, a small fraction of red nuggets survives, without any interaction, massive and compact until today: relic galaxies. Since this fraction depends on the processes dominating the size growth, counting relics at low-z is a valuable way to disentangle between different galaxy evolution models. In this paper, we introduce the INvestigating Stellar Population In RElics (INSPIRE) Project, that aims at spectroscopically confirming and fully characterizing a large number of relics at 0.1 80 % of their stellar mass within a short (0.5 - 1.0 Gyrs) initial star formation episode occurred only ~1 Gyr after the Big Bang. The third galaxy has a more extended star formation history and a lower velocity dispersion. Thus we confirm two out of three candidates as relics.

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C. Spiniello, C. Tortora, G. D'Ago, L. Coccato, F. La Barbera, A. Ferré-Mateu, N. R. Napolitano, M. Spavone, D. Scognamiglio, M. Arnaboldi, A. Gallazzi, L. Hunt, S. Moehler, M. Radovich, S. Zibetti. 2020-11-10. INSPIRE: INvestigating Stellar Population In RElics -- I. Survey presentation and pilot program. https://doi.org/10.1051/0004-6361/202038936

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