Context. Green Pea galaxies (GPs) are local starburst galaxies that serve as analogs for high-redshift star-forming galaxies, particularly Lyman continuum leakers. Historically considered isolated dwarfs, it remains debated whether their starbursts are driven by internal secular processes or external triggers. Aims. We aim to constrain the role of the environment in this triggering. Specifically, we test whether external influence comes from close galaxy–galaxy interactions or more diffuse processes, such as gas accretion within overdense regions. Methods. We analyze VLT/MUSE observations of 24 GPs at z). We find a high companion fraction (33^ searching for galaxies with spectral line features to identify companions. We derive key physical properties (extinction, star-formation rates, stellar mass, age, metallicity) for GPs and companions and estimate the dynamical mass of the groups. Results. We identify 22 emission-line galaxies, 11 of which are companions (|Δ v| łeq 500 km s -1 +11 _ -8 %) and a ∼1 dex excess in number density compared to the field, confirming that GPs reside in overdense environments. However, companions typically lie at projected separations of ∼100 kpc with no evidence of ongoing interactions. Physically, while both populations show star-forming excitation, GPs form a homogeneous class of young (stellar mass-weighted age ∼230 Myr), metal-poor, high-sSFR starbursts with elevated velocity dispersions. In contrast, companions are more evolved (∼1. 6 Gyr) and heterogeneous, spanning broader ranges in stellar mass, metallicity, and dust attenuation. The inferred group dynamical masses are ∼3 dex higher than total stellar masses, suggesting significant dark matter and neutral gas content. Conclusions. The GPs do not appear to be triggered by ongoing major mergers with close (10–30 kpc) companions. Instead, results favor a scenario where GPs are transient starbursts in overdense regions, plausibly sustained by gas accretion. However, the limited spatial resolution prevents us from ruling out very close mergers (łesssim10 kpc). Furthermore, the high dynamical-to-stellar mass ratios allow for substantial nonstellar mass components (i. e. , dark matter and/or neutral gas) in these systems.
Arroyo-Polonio et al. (Fri,) studied this question.