Unveiling the population of massive quenched galaxies at z≥2 in the COLIBRE simulations - II. The role of AGN feedback and environment on their emergence

@misc{chandrogomez2026unveiling,
  title = {{Unveiling the population of massive quenched galaxies at $z\ge2$ in the COLIBRE simulations - II. The role of AGN feedback and environment on their emergence}},
  author = {Ángel Chandro-Gómez and Claudia del P. Lagos and Chris Power and Willian M. Baker and Alejandro Benítez-Llambay and Evgenii Chaikin and Harry G. Chittenden and Camila Correa and Carlos S. Frenk and Filip Huško and Kei Ito and Robert J. McGibbon and Themiya Nanayakkara and Sylvia Ploeckinger and Alexander J. Richings and Matthieu Schaller and Joop Schaye and James W. Trayford and Francesco Valentino},
  howpublished = {arXiv},
  year = {2026},
  month = sep,
  doi = {10.48550/arxiv.2605.31052},
  eprint = {2605.31052},
  archivePrefix = {arXiv},
  url = {https://arxiv.org/abs/2605.31052},
  note = {CC BY 4.0},
}

TY  - UNPB
TI  - Unveiling the population of massive quenched galaxies at z≥2 in the COLIBRE simulations - II. The role of AGN feedback and environment on their emergence
AU  - Ángel Chandro-Gómez
AU  - Claudia del P. Lagos
AU  - Chris Power
AU  - Willian M. Baker
AU  - Alejandro Benítez-Llambay
AU  - Evgenii Chaikin
AU  - Harry G. Chittenden
AU  - Camila Correa
AU  - Carlos S. Frenk
AU  - Filip Huško
AU  - Kei Ito
AU  - Robert J. McGibbon
AU  - Themiya Nanayakkara
AU  - Sylvia Ploeckinger
AU  - Alexander J. Richings
AU  - Matthieu Schaller
AU  - Joop Schaye
AU  - James W. Trayford
AU  - Francesco Valentino
PY  - 2026
DA  - 2026/09/10
PB  - arXiv
DO  - 10.48550/arxiv.2605.31052
UR  - https://arxiv.org/abs/2605.31052
AB  - Early (z ≳ 2) Massive (M_⋆ ≳ 10^10 M_⊙), Quenched Galaxies (MQGs) challenge current galaxy formation models. In this series, we study these systems using the new COLIBRE cosmological hydrodynamical simulations. Following the broad agreement between their predictions and observations found in the first paper, this second paper explores the processes driving galaxies to become massive and quenched in COLIBRE, identifying Active Galactic Nucleus (AGN) feedback as the primary quenching mechanism in both the thermal (L200m6 simulation) and hybrid (thermal+jet, L200m7h simulation) AGN feedback models implemented. However, the two models behave differently: while the thermal model efficiently quenches massive galaxies at z>3, the hybrid model is less effective because black holes (BHs) grow more slowly in the early Universe, and the jet component, which dominates the feedback energy, acts on longer timescales to impact galaxies. Both models predict quasar-like MQGs (AGN with L_bol≳10^45 erg s^−1), with the most luminous systems associated with more recently quenched galaxies. Compared to star-forming galaxies of similar mass, MQGs host more massive BHs and exhibit higher star formation efficiencies. These differences arise primarily from their environments before quenching, particularly at local (0.3 cMpc) to intermediate scales (1.0 cMpc), where overdense regions are associated with enhanced gas inflows, higher BH accretion and, hence, feedback power. We find that about 54% (20%) of the z=3 MQGs survive as the main progenitors of z=0 galaxies, although up to 56% (60%) experience rejuvenation episodes at a given redshift z<3 in L200m6 (L200m7h). Our results highlight the central role of BH growth, AGN feedback and environment in driving rapid quenching in the early Universe.
ER  -