Open AccessDisc heating in NGC 2985
Author(s) -
Gerssen Joris,
Kuijken Konrad,
Merrifield Michael R.
Publication year - 2000
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1046/j.1365-8711.2000.03667.x
Subject(s) - physics , astrophysics , galaxy , velocity dispersion , hubble sequence , disc galaxy , galaxy formation and evolution
Various processes have been proposed to explain how galaxy discs acquire their thickness. A simple diagnostic for ascertaining this ‘heating’ mechanism is provided by the ratio of the vertical to radial velocity dispersion components. In a previous paper we have developed a technique for measuring this ratio, and demonstrated its viability on the Sb system NGC 488. Here we present follow‐up observations of the morphologically similar Sab galaxy NGC 2985, still only the second galaxy for which this ratio has been determined outside the solar neighbourhood. The result is consistent with simple disc‐heating models that predict ratios of σ z σ R less than one.