MAUVE-MUSE: A Star Formation-driven Outflow Caught in the Act of Quenching the Stripped Virgo Galaxy NGC 4064

TL;DR

This study investigates how rapid quenching of cluster satellites can be aided by star formation–driven outflows that expel remaining dense gas. Using MUSE data from the MAUVE survey, the authors perform 3D kinematic modeling with KinMS to separate disk rotation from non-circular outflow motions, focusing on Hα and [NII] emission. They identify a bi-polar ionized outflow in NGC 4064, measuring an outflow mass ~M_out ≈ 1.0×10^7 M_sun, a deprojected velocity v_out ≈ 95–97 km s^-1, and a mass loading factor η ≈ 1.66, with the outflow extending ~2 kpc and opening angle ~58 degrees; the ionization state is consistent with stellar feedback rather than an AGN. These results demonstrate that even modest, centrally concentrated star formation can efficiently drive feedback in stripped satellites, accelerating quenching, and lay the groundwork for statistical studies with MAUVE and ALMA follow-up across the Virgo environment.

Abstract

The rapid quenching of satellite galaxies in dense environments is often attributed to environmental processes such as ram pressure stripping. However, stripping alone cannot fully account for the removal of dense, star-forming gas in many satellites, particularly in their inner regions. Recent models and indirect observations have suggested that star formation-driven outflows may play a critical role in expelling this remaining gas, yet direct evidence for such feedback-driven quenching remains limited. Here we report the discovery of an ionized gas outflow in NGC 4064, a Virgo cluster satellite that has already lost most of its cold gas through environmental stripping. MUSE observations from the Multiphase Astrophysics to Unveil the Virgo Environment (MAUVE) survey reveal a bi-polar outflow driven by residual, centrally concentrated star formation in NGC 4064 - despite its current star formation rate being ~0.4 dex below the star-forming main sequence due to prior interaction with the cluster environment. The outflow's mass loading factor is ~2, suggesting that stellar feedback could remove the remaining gas on timescales shorter than those required for depletion by star formation alone. These results demonstrate that even modest but centrally concentrated star formation can drive efficient feedback in stripped satellites, accelerating quenching in the final stages of their evolution.

Figures (4)

• Figure 1: MUSE view of NGC 4064.Left: Color image constructed from the $g'$, $r$, and $i$-band maps extracted from the MAUVE-MUSE cubes. White contours indicate the H i distribution from Chung_2009, with the beam size of the radio observations shown in the bottom-left corner. Right: Integrated $\rm H\alpha$ flux map revealing an extended, bi-polar outflow of ionized gas emerging from the galaxy center. Note the presence of a foreground star on the eastern side that was masked. The white rectangle in both panels indicates the footprint of the MUSE mosaic.
• Figure 2: The stellar, ionized gas and modeled velocity maps of NGC 4064.Left: stellar velocity field from the MUSE data. Centre: $\rm H\alpha$ flux-weighted velocity map from the MUSE data. Right: Corresponding map from the best-fitting model cube of the gas disk component generated with KinMS.
• Figure 3: The ionized gas outflow of NGC 4064. The outflowing ionized gas, isolated by subtracting a kinematic model of the disk (Fig \ref{['fig2']}, right panel), is overlaid on the MUSE three-color image (same as Fig. \ref{['fig1']}, left panel). The white contours show the two largest contiguous regions of residual $\rm H\alpha$ flux. A foreground star on the eastern side was masked.
• Figure 4: Kinematics of the ionized outflow in NGC 4064.Left: Line-of-sight velocity map of the $\rm H\alpha$ outflow, with median velocities indicated for each lobe. Black contours trace the central stellar region as seen in the $\rm H\alpha$ flux. Right: Line-of-sight velocity distributions for the western (red) and eastern (blue) outflow lobes. Solid lines mark the median velocities.