Tidal pre-conditioning and ram-pressure stripping in NGC 1427A. Deep VLT/MUSE spectroscopy and FUV-to-radio observations trace a Fornax Cluster dwarf in transformation

Fuente: arXiv
Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: Carvajal, J. P., Puzia, T. H., Blaña, M., Nayak, P. K., Fahrion, K., Hilker, M., Emsellem, E., Skillman, E. D., Mora, M. D., Miller, B., Ordenes-Briceño, Y., Eigenthaler, P., Rahatgaonkar, R., Chanamé, J.
Format: Preprint
Veröffentlicht: 2026
Schlagworte:
Online-Zugang:
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
_version_ 1866913125470568448
author Carvajal, J. P.
Puzia, T. H.
Blaña, M.
Nayak, P. K.
Fahrion, K.
Hilker, M.
Emsellem, E.
Skillman, E. D.
Mora, M. D.
Miller, B.
Ordenes-Briceño, Y.
Eigenthaler, P.
Rahatgaonkar, R.
Chanamé, J.
author_facet Carvajal, J. P.
Puzia, T. H.
Blaña, M.
Nayak, P. K.
Fahrion, K.
Hilker, M.
Emsellem, E.
Skillman, E. D.
Mora, M. D.
Miller, B.
Ordenes-Briceño, Y.
Eigenthaler, P.
Rahatgaonkar, R.
Chanamé, J.
contents The early environmental transformation of low-mass cluster galaxies from gas-rich to gas-poor remains poorly constrained, partly because clear, phase-resolved observations are rare. NGC 1427A, a disturbed star-forming dwarf in the Fornax cluster, offers a favorable case for studying this process. We aim to build a spatially resolved, multi-phase picture of NGC 1427A to constrain the roles of ram-pressure stripping and tidal perturbations. We combine a deep, spatially contiguous VLT/MUSE mosaic with ancillary data from the FUV to the radio. Full-spectrum fitting of the MUSE cube yields maps of stellar kinematics, ages, metallicities, and continuum attenuation, while emission-line modeling provides ionized-gas kinematics, Balmer-decrement reddening, and star-formation-rate surface densities. Ancillary multi-wavelength data trace neutral and molecular gas, dust, and recent star formation, placing the MUSE-based results in a broader multi-phase context. We find a pronounced decoupling between stars and gas: the H I and ionized gas rotate about an axis tilted with respect to the stellar field and are globally blueshifted. Stellar and nebular attenuation, infrared dust tracers, and H I morphology indicate stripping with a strong line-of-sight component that has reached the ISM. At the same time, the asymmetric gas and dust distribution, together with structured and time-dependent star formation, points to an additional gravitational perturbation, with a recent mild fly-by by a nearby dwarf being the favored interpretation. We propose that dwarf-dwarf tidal effects have torqued and pre-conditioned the gas, while the Fornax intracluster medium is driving ram-pressure stripping that now reaches the ISM and coincides with a declining global star formation rate. This places NGC 1427A at the onset of environmental quenching, making it a useful benchmark for early cluster dwarf transformation.
format Preprint
id arxiv_https___arxiv_org_abs_2605_00988
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Tidal pre-conditioning and ram-pressure stripping in NGC 1427A. Deep VLT/MUSE spectroscopy and FUV-to-radio observations trace a Fornax Cluster dwarf in transformation
Carvajal, J. P.
Puzia, T. H.
Blaña, M.
Nayak, P. K.
Fahrion, K.
Hilker, M.
Emsellem, E.
Skillman, E. D.
Mora, M. D.
Miller, B.
Ordenes-Briceño, Y.
Eigenthaler, P.
Rahatgaonkar, R.
Chanamé, J.
Astrophysics of Galaxies
The early environmental transformation of low-mass cluster galaxies from gas-rich to gas-poor remains poorly constrained, partly because clear, phase-resolved observations are rare. NGC 1427A, a disturbed star-forming dwarf in the Fornax cluster, offers a favorable case for studying this process. We aim to build a spatially resolved, multi-phase picture of NGC 1427A to constrain the roles of ram-pressure stripping and tidal perturbations. We combine a deep, spatially contiguous VLT/MUSE mosaic with ancillary data from the FUV to the radio. Full-spectrum fitting of the MUSE cube yields maps of stellar kinematics, ages, metallicities, and continuum attenuation, while emission-line modeling provides ionized-gas kinematics, Balmer-decrement reddening, and star-formation-rate surface densities. Ancillary multi-wavelength data trace neutral and molecular gas, dust, and recent star formation, placing the MUSE-based results in a broader multi-phase context. We find a pronounced decoupling between stars and gas: the H I and ionized gas rotate about an axis tilted with respect to the stellar field and are globally blueshifted. Stellar and nebular attenuation, infrared dust tracers, and H I morphology indicate stripping with a strong line-of-sight component that has reached the ISM. At the same time, the asymmetric gas and dust distribution, together with structured and time-dependent star formation, points to an additional gravitational perturbation, with a recent mild fly-by by a nearby dwarf being the favored interpretation. We propose that dwarf-dwarf tidal effects have torqued and pre-conditioned the gas, while the Fornax intracluster medium is driving ram-pressure stripping that now reaches the ISM and coincides with a declining global star formation rate. This places NGC 1427A at the onset of environmental quenching, making it a useful benchmark for early cluster dwarf transformation.
title Tidal pre-conditioning and ram-pressure stripping in NGC 1427A. Deep VLT/MUSE spectroscopy and FUV-to-radio observations trace a Fornax Cluster dwarf in transformation
topic Astrophysics of Galaxies
url https://arxiv.org/abs/2605.00988