Special Session Sp16  23 – 24 June 2015

The outskirts of galaxies: present status and future challenges

Aims and scope

The aim of this Special Session is to bring out the importance of studying the outskirts of galaxies because of the unique set of clues about galaxy evolution in general which we find in these outer discs and stellar halos. The basis of the Session will be to describe the observational work already known and published. This will include work on the surface brightness profiles of galaxies at low and intermediate redshifts, studies of what we can deduce using "galactic archaeology" i.e. fields of star streams in images reaching very low surface brightness, and in local galaxies studies of stellar populations in the outer zones. After that we will look at the status of theoretical models which have been proposed to explain the observations, starting with how cosmological models address galaxy light profiles, and continuing with simulations designed to yield specific results, such as stellar disc truncations and antitruncations. The third part of the Session will be devoted to optimizing the observing strategy for detecting and quantifying low surface brightness structures, including work with current instrumentation and projected work with new instruments.


  • Light profiles and colour profiles of galaxies at low and intermediate redshift.
  • Structure of the outskirts of galaxies: truncations, warps, flares and stellar haloes.
  • Stellar populations in the outskirts of galaxies.
  • Observational constraints from galactic archaeology.
  • Theoretical profiles from cosmological models.
  • Theoretical models from detailed simulations.
  • Optimizing future observing strategies for low surface brightness structures.
  • Current and future surveys with present and future instruments.

Invited speakers

  • Jean-Charles Cuillandre (CEA IRFU): Processing extremely deep images: Elixir-LSB
  • Lia Athanassoula (LAM): The outer parts of disc galaxies: Input from simulations
  • David Valls-Gabaud (LERMA): New instrumentation for LSB studies
  • Olga K. Sil'chenko (SAI MSU): Outer disks and rings of the lenticular galaxies
  • Heikki Salo (U. Oulu): The disk properties from decompositions of S4G galaxies
  • Christer Sandin (AIP): The diffuse scattered light around galaxies
  • Peter Erwin (MPIA): Surface-brightness and star-formation profiles of galaxy disks: Observational perspectives, problems, questions, and possible answers
  • David Maltby (UNOT): The structure of galactic discs in the STAGES survey: probing the drivers of galaxy evolution

Scientific organisers
John Beckman (IAC, Tenerife, Spain), Pierre-Alain Duc (CEA, Saclay, France), Carmen Eliche Moral (Universidad Computense, Madrid, Spain), Alejandro Borlaff (IAC, Tenerife, Spain), Nacho Trujillo (IAC, Tenerife, Spain), Mercedes Prieto (IAC, Tenerife, Spain)

John Beckman jeb @ iac.es, Pierre-Alain Duc paduc @ cea.fr, Carmen Eliche mceliche @ fis.ucm.es, Alejandro Borlaff asborlaff @ iac.es, Nacho Trujillo trujillo @ iac.es, Mercedes Prieto mpm @ iac.es

Updated on Fri Feb 20 16:54:10 CET 2015