Formation of Disk Galaxies: On the Angular Momentum Problem, the Tully-Fisher Relation and Magnetohydrodynamics

The large-scale dynamics and evolution of disk galaxies is controlled by the angular-momentum transport provided by non-axisymmetric perturbances through their gravity torques. To continuously maintain such gravitational instabilities, the presence of the gas component and its dissipative character are essential.

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The Tully-Fisher relation: evolution with redshift and environment

Proceedings of the International Astronomical Union ◽

10.1017/s1743921306004947 ◽

2006 ◽

Vol 2 (S235) ◽

pp. 8-11 ◽

Cited By ~ 1

Author(s):

Alfonso Aragón-Salamanca

Keyword(s):

Spiral Galaxies ◽

Rotation Velocity ◽

Disk Galaxies ◽

Cluster Galaxies ◽

Fundamental Properties ◽

Look Back ◽

Formation And Evolution ◽

Fisher Relation

AbstractThe Tully-Fisher Relation (TFR) links two fundamental properties of disk galaxies: their luminosity and their rotation velocity (mass). The pioneering work of Vogt et al. in the 1990's showed that it is possible to study the TFR for spiral galaxies at considerable look-back-times, and use it as a powerful probe of their evolution. In recent years, several groups have studied the TFR for galaxies in different environments reaching redshifts beyond one. In this brief review I summarise the main results of some of these studies and their consequences for our understanding of the formation and evolution of disk galaxies. Particular emphasis is placed on the possible environment-driven differences in the behaviour of the TFR for field and cluster galaxies.

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The Angular Momentum Dichotomy

Proceedings of the International Astronomical Union ◽

10.1017/s1743921314010400 ◽

2014 ◽

Vol 10 (S309) ◽

pp. 349-349

Author(s):

Adelheid Teklu ◽

Rhea-Silvia Remus ◽

Klaus Dolag ◽

Andreas Burkert

Keyword(s):

Dark Matter ◽

Angular Momentum ◽

Lognormal Distribution ◽

Spiral Galaxies ◽

Disk Galaxies ◽

Dark Matter Halos ◽

Central Galaxy ◽

Relative Angular Momentum ◽

Spin Parameter ◽

Spheroidal Galaxies

AbstractIn the context of the formation of spiral galaxies the evolution and distribution of the angular momentum of dark matter halos have been discussed for more than 20 years, especially the idea that the specific angular momentum of the halo can be estimated from the specific angular momentum of its disk (e.g. Fall & Efstathiou (1980), Fall (1983) and Mo et al. (1998)). We use a new set of hydrodynamic cosmological simulations called Magneticum Pathfinder which allow us to split the galaxies into spheroidal and disk galaxies via the circularity parameter ϵ, as commonly used (e.g. Scannapieco et al. (2008)). Here, we focus on the dimensionless spin parameter λ = J |E|1/2 / (G M5/2) (Peebles 1969, 1971), which is a measure of the rotation of the total halo and can be fitted by a lognormal distribution, e.g. Mo et al. (1998). The spin parameter allows one to compare the relative angular momentum of halos across different masses and different times. Fig. 1 reveals a dichotomy in the distribution of λ at all redshifts when the galaxies are split into spheroids (dashed) and disk galaxies (dash-dotted). The disk galaxies preferentially live in halos with slightly larger spin parameter compared to spheroidal galaxies. Thus, we see that the λ of the whole halo reflects the morphology of its central galaxy. For more details and a larger study of the angular momentum properties of disk and spheroidal galaxies, see Teklu et al. (in prep.).

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Mass to Light Ratio, Initial Mass Function, and Chemical Evolution in Disk Galaxies

Publications of the Astronomical Society of Australia ◽

10.1071/as04019 ◽

2004 ◽

Vol 21 (2) ◽

pp. 144-147 ◽

Cited By ~ 1

Author(s):

L. Portinari ◽

J. Sommer-Larsen ◽

R. Tantalo

Keyword(s):

Galaxy Formation ◽

Chemical Properties ◽

Zero Point ◽

Mass Function ◽

Initial Mass Function ◽

Initial Mass ◽

Disk Galaxies ◽

Stellar Component ◽

Low Mass ◽

Fisher Relation

AbstractCosmological simulations of disk galaxy formation, when compared to the observed Tully–Fisher relation, suggest a low mass to light (M/L) ratio for the stellar component in spirals. We show that a number of 'bottom-light' initial mass functions (IMFs) suggested independently in the literature, do imply M/L ratios as low as required, at least for late type spirals (Sbc–Sc). However the typical M/L ratio, and correspondingly the zero point of the Tully–Fisher relation, is expected to vary considerably with Hubble type.Bottom-light IMFs tend to have a metal production in excess of what is typically estimated for spiral galaxies. Suitable tuning of the IMF slope and mass limits, post-supernova fallback of metals onto black holes or metal outflows must then be invoked, to reproduce the observed chemical properties of disk galaxies.

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Lenticular vs spiral galaxies: dark matter content and the Tully-Fisher relation

Proceedings of the International Astronomical Union ◽

10.1017/s1743921310008355 ◽

2009 ◽

Vol 5 (H15) ◽

pp. 82-82

Author(s):

M. Bureau ◽

M. J. Williams ◽

M. Cappellari

Keyword(s):

Dark Matter ◽

Galaxy Evolution ◽

Spiral Galaxies ◽

Matter Content ◽

Disk Galaxies ◽

Observational Constraints ◽

Modelling Techniques ◽

Fisher Relation ◽

Local Edge ◽

Zero Points

We provide observational constraints on disk galaxy evolution for a sample of 28 local edge-on early-type (S0–Sb) disk galaxies. We do this in two ways: (i) we use simple dynamical modelling techniques to constrain their stellar and dark matter content (Williams et al. 2009) and (ii) we compare the zero points of the Tully-Fisher relations (TFRs; Tully & Fisher 1977) of the spirals and S0s.

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Formation and Evolution of Disk Galaxies

Symposium - International Astronomical Union ◽

10.1017/s0074180900132334 ◽

1999 ◽

Vol 183 ◽

pp. 153-153

Author(s):

C. Firmani ◽

V. Avila-Reese

Keyword(s):

Dark Matter ◽

Angular Momentum ◽

Power Spectrum ◽

Mass Velocity ◽

Dark Matter Halo ◽

Stellar Disk ◽

Physical Factors ◽

Disk Galaxies ◽

Velocity Relation ◽

Formation And Evolution

We have developed a semianalitical approach to study galaxy formation and evolution in the cosmological context. Disk galaxies (dark matter halo+luminous disk) are considered to be formed through an extended process of gravitational collapse, whose character is determined by the statistical properties of the density fluctuation field assumed here to be Gaussian. Gas disks in centrifugal equilibrium within the collapsing dark halos are built up (detailed angular momentum conservation is assumed), and their galactic evolution is calculated with a model which consider all the gravitational interactions, the hydrodynamics of the ISM, and the SF process. A bulge as product of stellar disk gravitational instabilities is constructed. To study general behaviors a Gaussian σ8 = 1 SCDM model is used. For a given mass one obtains a range of dark matter configurations. The average case is in excellent agreement with results of cosmological N-body simulations. The slope of the mass-velocity relation agrees with the slope of the H- and I-band Tully-Fisher relations, but the velocities are too high. This problem dissapears if the power spectrum is renormalized to σ8 = 0.57, suggesting that the TF relation is result of the natural extension to galactic scales of the galaxy distribution power spectrum, and that on the basis of its origin are the cosmological initial conditions. The scatter on the mass-velocity relation is realistic. The models predict disk exponential surface brightness (SB) profiles, nearly flat rotation curves, and negative radial gradients in the B-V color. The obtained, gas fractions, B-V colors, central SBs μB0, bulge-to-disk (b/d) ratios, and rotation velocities (for σ8 = 0.57) are in agreement with observations, and their correlations are similar to those which define the Hubble sequence, including the LSB galaxies. These properties and correlations are the product of the combination of three fundamental physical factors: the mass, the mass aggregation history (MAH), and the initial angular momentum. The intensive properties are almost invariant to the mass, the MAH determines the B-V color, and the spin parameter λ mainly influences on μB0, and b/d ratio.

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Formation of Disk Galaxies: Feedback and the Angular Momentum Problem

The Astrophysical Journal ◽

10.1086/307374 ◽

1999 ◽

Vol 519 (2) ◽

pp. 501-512 ◽

Cited By ~ 110

Author(s):

Jesper Sommer‐Larsen ◽

Sergio Gelato ◽

Henrik Vedel

Keyword(s):

Angular Momentum ◽

Disk Galaxies

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Simulating Disk Galaxies: First Results of a Systematical Study

Proceedings of the International Astronomical Union ◽

10.1017/s1743921306005461 ◽

2006 ◽

Vol 2 (S235) ◽

pp. 114-114 ◽

Cited By ~ 2

Author(s):

Franziska Köckert ◽

Matthias Steinmetz

Keyword(s):

Angular Momentum ◽

Galaxy Formation ◽

Initial Conditions ◽

Disk Galaxies ◽

Disk Formation ◽

Numerical Resolution ◽

First Results ◽

Low Mass ◽

Current Paradigm ◽

Made In

Simulating disk galaxies within the current paradigm of galaxy formation has been a long standing problem. In comparison with observations, the simulated disks were too small and too centrally concentrated, due to a large loss of angular momentum during formation. This is known as the angular momentum catastrophe (Navarro & Benz (1991)). Recently, some progress has been made in reducing this effect by changing the cosmology, including various feedback mechanisms, improving numerical resolution and carefully selecting initial conditions with a quiet merging history after z≈2. Unfortunately, it remains unclear which of these effects, or which combination, has resulted in more realistic disk formation. In order to address this problem, we conduct a systematical study using the N-body code GADGET2 (Springel (2005)). We adopt a flat ΛCDM cosmology with Ωm=0.3, ΩΛ=0.7, Ωbar=0.04 and h=0.65. Using a softening of 0.5 kpc we find disks with a very compact unresolved gas clump in the center and a thin, extended disk (R≈10kpc) of very low mass around it.

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Formation of Disk Galaxies: Warm Dark Matter and the Angular Momentum Problem

The Astrophysical Journal ◽

10.1086/320211 ◽

2001 ◽

Vol 551 (2) ◽

pp. 608-623 ◽

Cited By ~ 177

Author(s):

Jesper Sommer‐Larsen ◽

Alexandre Dolgov

Keyword(s):

Dark Matter ◽

Angular Momentum ◽

Disk Galaxies

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Evolution of the Mass-to-light Ratio of Galaxies to z~ 0.25

Proceedings of the International Astronomical Union ◽

10.1017/s1743921306010283 ◽

2006 ◽

Vol 2 (S235) ◽

pp. 395-396

Author(s):

B. Catinella ◽

M. P. Haynes ◽

J. P. Gardner ◽

A. J. Connolly ◽

R. Giovanelli

Keyword(s):

Optical Spectroscopy ◽

Line Emission ◽

Zero Point ◽

Disk Galaxies ◽

Rotation Curves ◽

First Results ◽

Fisher Relation ◽

Intermediate Redshifts

AbstractWe present the first results of a targeted survey carried out with the 305m Arecibo radiotelescope to detect HI-line emission from disk galaxies at redshift z > 0.16. We are using this sample to study the evolution of the zero point of the Tully-Fisher relation (TFR) for galaxies at intermediate redshifts. Compared to optical widths, HI measurements sample a larger fraction of the disks, where the rotation curves are typically flat, and are not affected by slit smearing and misalignment or by aperture effects. Thus, in contrast to studies based on optical spectroscopy, this dataset allows for a direct comparison with the local TFR that is technique independent.

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