Symposium S8  29 – 30 June 2017

Aims and scope

Ram pressure stripping is a common process that describes the removal of a galaxy's gaseous components due to its motion through the surrounding medium in a variety of environments from the Local group to rich clusters. It can strongly disturb the galaxy's star-forming interstellar matter (ISM) and quench star formation (SF), but also temporarily boost it at some places. This changes the baryon content of dwarf galaxies, makes the cluster late-type galaxies migrate towards passively evolving gas-poor types in the color-magnitude diagram, and contributes to the bimodal population of galaxies (red sequence vs. blue cloud). The galaxies caught in the act of stripping show asymmetric gas distributions, decoupled ISM components, SF enhanced by gas compression, and extra-planar emission that can be bright in multiple wavelengths. Recently, ongoing SF in stripped gas, often in the form of long parallel streams of young stars, has been revealed in 'jellyfish' galaxies, including examples from intermediate redshifts. Ram pressure stripping is also likely to be important for starvation, or the prevention of halo gas from accreting, thus quenching SF in galaxies outside of clusters. It is also a key process for other topics like narrow-angle tailed radio galaxies or X-ray coronas of early-type galaxies.

In recent years there has been growing awareness that together with mergers and tidal interactions ram pressure stripping is a crucial mechanism in driving galaxy evolution over cosmic time. Newly operating (sub-)millimeter interferometers (such as ALMA or NOEMA) and highly efficient integral-field unit spectrographs (such as MUSE), as well as observations with space observatories (HST, Chandra) have provided an unprecedented level of new knowledge, extending the classical picture, but also revealing new challenges and contradictions.

The interaction between the multi-phase interstellar medium of a galaxy and its surrounding hot, diffuse intra-cluster medium comprises a rich mixture of physical processes and its understanding is a challenge for both observers and theorists. The goal of the Symposium is to gather researchers actively working in the field, to present and discuss the up-to-date advances and discoveries, as well as identify the urgent questions and initiate discussions on their solution strategies, especially: Star formation histories of cluster galaxies and their evolutionary paths; Ram pressure stripping at high redshifts; Stripping of the realistic, multi-density, multi-phase ISM; Fate of the stripped gas; Role of magnetic fields; Star formation in the stripped ISM; Ram pressure stripping as a starvation mechanism in cluster outskirts and groups; Effects of ram pressure in less extreme environments; How do new observational results inform the semi-analytic models and sub-grid physics in simulations?


  • Multi-wavelength observations of stripping
  • Impact on galaxy evolution
  • Theoretical advances

Invited speakers

  • A. Boselli (LAM)
  • G. Besla (University of Arizona)
  • H. Ebeling (IfA, University of Hawaii)
  • M. Fossati (MPE)
  • Y. L. Jaffe (ESO)
  • P. Nulsen (CfA Harvard)
  • M. Ruszkowski (University of Michigan in Ann Arbor)
  • S. Sivanandam (Dunlap Institute for Astronomy and Astrophysics)
  • M. Yagi (NAOJ)
  • M. Yoshida (Hiroshima Astrophysical Science Center)
  • B. Vollmer (Observatoire Astronomique Strasbourg)
  • ...

Scientific organisers

  • Pavel Jachym (Czech Academy of Sciences, CZ)
  • Elke Roediger (University of Hull, UK)
  • Jeffrey Kenney (Yale University, USA)
  • Ming Sun (University of Alabama in Huntsville, USA)
  • Luca Cortese (University of Western Australia)

jachym @

Updated on Thu Mar 30 10:01:42 CEST 2017