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ABSTRACT Cluster spiral galaxies suffer catastrophic losses of the cool, neutral gas component of their interstellar medium due to ram pressure stripping, contributing to the observed quenching of star formation in the disc compared to galaxies in lower density environments. However, the short-term effects of ram pressure on the star formation rate and active galactic nucleus (AGN) activity of galaxies undergoing stripping remain unclear. Numerical studies have recently demonstrated cosmic rays can dramatically influence galaxy evolution for isolated galaxies, yet their influence on ram pressure stripping remains poorly constrained. We perform the first cosmic ray magnetohydrodynamic simulations of an L* galaxy undergoing ram pressure stripping, including radiative cooling, self-gravity of the gas, star formation, and stellar feedback. We find the microscopic transport of cosmic rays plays a key role in modulating the star formation enhancement experienced by spirals at the outskirts of clusters compared to isolated spirals. Moreover, we find that galaxies undergoing ram pressure stripping exhibit enhanced gas accretion on to their centres, which may explain the prevalence of AGNs in these objects. In agreement with observations, we find cosmic rays significantly boost the global radio emission of cluster spirals. Although the gas removal rate is relatively insensitive to cosmic ray physics, we find that cosmic rays significantly modify the phase distribution of the remaining gas disc. These results suggest observations of galaxies undergoing ram pressure stripping may place novel constraints on cosmic ray calorimetry and transport.
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The effect of cosmic web filaments on galaxy properties in the RESOLVE and ECO surveys
ABSTRACT Galaxy environment plays an important role in driving the transformation of galaxies from blue and star forming to red and quenched. Recent works have focused on the role of cosmic web filaments in galaxy evolution and have suggested that stellar mass segregation, quenching of star formation, and gas-stripping may occur within filaments. We study the relationship between distance to filament and the stellar mass, colour, and H i gas content of galaxies using data from the REsolved Spectroscopy of a Local VolumE survey and Environmental COntext (ECO) catalogue, two overlapping census-style, volume-complete surveys. We use the Discrete Persistence Structures Extractor to identify cosmic web filaments over the full ECO area. We find that galaxies close to filaments have higher stellar masses, in agreement with previous results. Controlling for stellar mass, we find that galaxies also have redder colours and are more gas poor closer to filaments. When accounting for group membership and halo mass, we find that these trends in colour and gas content are dominated by the increasing prevalence of galaxy group environments close to filaments, particularly for high-halo mass and low-stellar mass galaxies. Filaments have an additional small effect on the gas content of galaxies in low-mass haloes, possibly due to cosmic web stripping.
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- PAR ID:
- 10490232
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- Monthly Notices of the Royal Astronomical Society
- Volume:
- 528
- Issue:
- 3
- ISSN:
- 0035-8711
- Format(s):
- Medium: X Size: p. 4139-4159
- Size(s):
- p. 4139-4159
- Sponsoring Org:
- National Science Foundation
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