Open AccessDark matter in early‐type galaxies: dynamical modelling of IC 1459, IC 3370, NGC 3379 and NGC 4105
Author(s) -
Samurović S.,
Danziger I. J.
Publication year - 2005
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 - 10.1111/j.1365-2966.2005.09479.x
Subject(s) - physics , astrophysics , galaxy , dark matter , type (biology) , line of sight , line (geometry) , spectral line , astronomy , geometry , ecology , biology , mathematics
We analyse long‐slit spectra of four early‐type galaxies which extend from ∼1 to 3 effective radii: IC 1459; IC 3370; NGC 3379 and NGC 4105. We have extracted the full line‐of‐sight velocity distribution (in the case of NGC 3379 we also used data from the literature), which we model using the two‐integral approach. Using two‐integral modelling, we find no strong evidence for dark haloes, but the fits suggest that three‐integral modelling is necessary. We also find that the inferred constant mass‐to‐light ratio in all the four cases is typical for early‐type galaxies. Finally, we also discuss the constraints on the mass‐to‐light ratio, which can be obtained using X‐ray haloes in the case of IC 1459, NGC 3379 and NGC 4105, and compare the estimated values with the predictions from the dynamical modelling.