2025/08/27 by Catherine C. Gibson, Gibson, Catherine C., Jackson H. O’Donnell +3 · 1 voice · 1 citation
Physics and Astronomy · #Astronomy and Astrophysical Research #Astrophysics and Star Formation Studies #Stellar, planetary, and galactic studies
paper · doi:10.33232/001c.160280
openalex created_date 2025/09/24 · openalex publication_date 2026/04/09 · openalex updated_date 2026/08/03
We investigate the effects of ram-pressure stripping on four galaxies within the massive, strong-lensing cluster MACS-J0138.0-2155 ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mrow> <mml:mi>z</mml:mi> <mml:mo>=</mml:mo> <mml:mn>0.336</mml:mn> </mml:mrow> </mml:math> ). Of these, three are classified as jellyfish galaxies, with significant elongated tails. Two of these jellyfish galaxies, J1 and J2, are in a late-stage of stripping and show post-starburst features within their disk regions with star formation only in the tails. Using VLT/MUSE integral field spectroscopic data, we spatially resolve the stellar and gas kinematics to examine extraplanar gas associated with ram-pressure stripping. We complement this analysis with optical and near-infrared imaging from the Hubble Space Telescope to visualize the galactic structure of each member. The jellyfish galaxies are all blue-shifted with respect to the cluster and show velocity gradients of a few hundred <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:msup> <mml:mrow> <mml:mi mathvariant="normal">k</mml:mi> <mml:mi mathvariant="normal">m</mml:mi> <mml:mi mathvariant="normal">s</mml:mi> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>1</mml:mn> </mml:mrow> </mml:msup> </mml:math> across their tails. From the resolved gas kinematics, we derive H <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mi>α</mml:mi> </mml:math> -based star formation rates; these are generally low reaching a maximum of approximately 0.49 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mrow> <mml:msub> <mml:mi mathvariant="normal">M</mml:mi> <mml:mo mathvariant="normal">⊙</mml:mo> </mml:msub> <mml:msup> <mml:mtext mathvariant="normal">yr</mml:mtext> <mml:mrow> <mml:mo mathvariant="normal">−</mml:mo> <mml:mn mathvariant="normal">1</mml:mn> </mml:mrow> </mml:msup> <mml:mi mathvariant="normal">k</mml:mi> <mml:mi mathvariant="normal">p</mml:mi> <mml:msup> <mml:mi mathvariant="normal">c</mml:mi> <mml:mrow> <mml:mo mathvariant="normal">−</mml:mo> <mml:mn mathvariant="normal">2</mml:mn> </mml:mrow> </mml:msup> </mml:mrow> </mml:math> in galaxy J3. We also report the kinematics for galaxy J4, which lies in the foreground of the cluster but close in projection to one of the lensed arcs.