Bibcode
Beckman, J. E.; Irwin, P.; Pohlen, M.
Bibliographical reference
Lecture Notes and Essays in Astrophysics, vol. 2, p. 199-214.
Advertised on:
12
2006
Citations
0
Refereed citations
0
Description
stronomers have long learned to classify spirals in terms of their
morphological features, primarily their bulges, discs, and bars. In
addition other properties of discs are used in classification, notably
spiral arms, warps and truncations. In this paper we show how with
modern techniques parts of the basis of these standard classifications
are shown to be unsatisfactory, even misleading. In particular we will
look carefully at bulges and at truncations, and explain how on purely
morphological grounds we need to make basic changes in our concepts. We
will put in question the traditional view of the spheroidal bulge and
will also show that the majority of galaxy discs are not in fact
truncated.