The miniJPAS survey: The role of group environment in quenching the star formation

R. M. González Delgado, J. E. Rodríguez-Martín, L. A. Díaz-García, A. de Amorim, R. García-Benito, G. Martínez-Solaeche, P. A. A. Lopes, M. Maturi, E. Pérez, R. Cid Fernandes, A. Cortesi, A. Finoguenov, E. R. Carrasco, A. Hernán-Caballero, L. R. Abramo, J. Alcaniz, N. Benítez, S. Bonoli, A. J. Cenarro, D. Cristóbal-Hornillos, J. M. Diego, R. A. Dupke, A. Ederoclite, J. A. Fernández-Ontiveros, C. López-Sanjuan, A. Marín-Franch, I. Márquez, C. Mendes de Oliveira, M. Moles, I. Pintos, L. Sodré Jr., K. Taylor, J. Varela, H. Vázquez Ramió, J. M. Vílchez

Submitted on 12 July 2022


The miniJPAS survey has observed 1 deg2 on the AEGIS field with 60 bands (spectral resolution of R60) in order to demonstrate the capabilities of the Javalambre-Physics of the Accelerating Universe Astrophysical Survey (J-PAS) that will map 8000 deg2 of the northern sky in the next years. This paper shows the power of J-PAS to detect low mass groups and characterise their galaxy populations up to z1. We use the spectral energy distribution fitting code BaySeAGal to derive the stellar population properties of the galaxy members in 80 groups at z0.8 previously detected by the AMICO code, as well as for a galaxy field sample retrieved from the whole miniJPAS sample. We identify blue, red, quiescent, and transition galaxy populations through their rest-frame (extinction corrected) colour, stellar mass (M) and specific star formation rate. We measure their abundance as a function of M and environment. We find: (i) The fraction of red and quiescent galaxies in groups increases with M and it is always higher in groups than in the field. (ii) The quenched fraction excess (QFE) in groups strongly increases with M, (from a few percent to higher than 60% in the mass range 10103×1011 M. (iii) The abundance excess of transition galaxies in groups shows a modest dependence with M (iv) The fading time scale is very short (<1.5 Gyr), indicating that the star formation declines very rapidly in groups. (v) The evolution of the galaxy quenching rate in groups shows a modest but significant evolution since z0.8, compatible with an evolution with constant QFE=0.4, previously measured for satellites in the nearby Universe, and consistent with a scenario where the low-mass star-forming galaxies in clusters at are environmentally quenched.


Comment: 21 pages, 20 figures, accepted for publication in Astronomy & Astrophysics

Subject: Astrophysics - Astrophysics of Galaxies