Types of Galaxies| Types of Galaxies |
In General > s.a. galaxies;
galaxy evolution [active galactic nuclei, spiral agalaxies].
* In terms of their shape:
Irregular (Irr); Spiral (S0, Sa, Sb, Sc), richer in gas (star formation); Barred spiral
(SB0, SBa, SBb, SBc); Elliptic (E0... E7), giants up to 105 pc,
1012 solar masses, denser and hotter; The majority
of galaxies are dwarf ellipticals, but most of the large ones are spirals.
* In terms of emission:
Quiet and active (Radio, Seyfert, Emission line BL Lacertae objects).
* Questions: How fundamentally
different are the various kinds of active galaxies listed, and how many of
the differences just depend on our observations? How many differences are a
function of time and change with collisions and mergers?
@ By neural network: Lahav et al ap/95;
Mähönen & Hakala ApJ(95)ap.
@ Classification systems:
Van den Bergh AJ(97)ap;
Conselice MNRAS(06)ap;
van den Bergh A&A(08)-a0808 [luminosity-diameter relation];
Wijesinghe et al MNRAS-a1001;
Forbes & Kroupa PASA(11)-a1101 [definition, galaxy vs star cluster];
Krajnović pw(11)nov-a1604 [using 3D views of galaxies];
Fraix-Burnet et al a1508 [different approaches, rev].
@ Types: Dunlop pw(97)jan [radio];
Bothun SA(97)feb [low surface brightness];
Collins CP(99) [primeval];
Blain in(01)ap/00 [starburst];
van den Bergh AJ(07)-a0706 [in general];
Gadotti a0802-ch [barred];
Kitchin 07;
Nair & Abraham ApJL(10)-a1004 [barred spirals, fraction];
Wadadekar a1201-conf [morphology];
Katkov a1403 [isolated lenticular galaxies];
Kalinova et al a1509/MNRAS [dynamical classification system];
> s.a. supermassive black holes [ultracompact dwarf galaxy].
@ Structure:
Maciejewski & Sparke ap/98-proc [bars and structure];
Voglis et al MNRAS(06)ap [invariant manifolds and chaotic orbits in spiral galaxies];
Jog & Combes PRP(09) [lopsided spiral galaxies];
van der Kruit a1004-fs,
van der Kruit & Freeman ARAA(11)-a1101 [disks];
Salo et al ApJL(10)-a1004 [bars and density waves];
Courteau et al RMP(14) [masses].
@ Related topics:
Lintott & Land pw(08)sep,
Masters a1303-proc [Galaxy Zoo project];
> s.a. astronomical objects [globular clusters];
galaxy distribution [different environments].
Dwarf Galaxies
* Size: Dwarf galaxies go down
to 103 pc, 107
MSun.
* Dwarf spheroidals: 2015, Only
the dwarf spheroidals around the Milky Way and the Andromeda galaxy are bright enough
to study; They are similar enough to their galactic hosts that they could have started
to form at the same time; About 60% of Andromeda's dwarf spheroidals occupy a more-or-less
spherical halo around their host, while the rest occupy a thin pancake-shaped region that
encompasses Andromeda's galactic plane; Studies suggest that Andromeda's on-plane and off-plane
dwarfs formed at the same time from the same material, but the prevailing cosmological
framework struggles to account for such a starkly bimodal distribution.
@ General references: Beck SA(00)jun [starburst];
Salvadori a1204-conf [cosmological view];
Bellazzini a1210-conf [and globular clusters];
Kormendy a1405-conf [structure and evolution];
Ibata et al a1407 [velocity correlations of satellite galaxies];
Javanmardi et al A&A(16)-a1511 [discovery with amateur telescopes];
Read et al a1601/MNRAS [rotation curves];
> s.a. local group.
@ Specific galaxies: Sandoval et al a1506/ApJL [record-breaking compact stellar systems].
Satellites, Pairs, Groups of Galaxies > s.a. galaxy
distribution [including clusters]; local group.
* Closest cluster: The closest
clustering outside the Local Group is the Antlia-Sextans, at 1.36 Mpc.
@ Pairs of galaxies: Juszkiewicz et al ApJL(99)ap/98 [relative velocity];
Hashimoto et al ApJ(03)ap/02 [orbit evolution];
Azzaro et al ap/03-proc [satellites].
@ Satellites: Cyr-Racine et al PRD(16)-a1506 [of distant galaxies];
Welker et al a1512/MNRAS [alignment with the galactic plane].
@ Satellites, velocity dispersion: Zhao et al ApJ(02)ap [theory];
Jing & Börner ApJ(04)ap;
Brainerd ap/04/ApJ.
@ Groups and satellites: Sales & Lambas MNRAS(05)ap/04 [statistics];
Macciò et al MNRAS(05)ap/04 [dark energy and local Hubble flow];
Zentner et al ApJ(05)ap [anisotropic distribution];
Agustsson & Brainerd ApJL(06)ap/05,
Yang et al MNRAS(06)ap,
Kang et al MNRAS(07)ap [alignment];
Moffat & Toth a0708 [and modified gravity, MOG];
Libeskind et al MNRAS(15)-a1503 [planes of satellites and the cosmic web].
main page
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send feedback and suggestions to bombelli at olemiss.edu – modified 11 aug 2019