Dark matter in spiral galaxies. II - Galaxies with H I rotation curves

1987 ◽  
Vol 93 ◽  
pp. 816 ◽  
Author(s):  
Stephen M. Kent
Keyword(s):  
Dark Matter ◽  
Spiral Galaxies ◽  
Rotation Curves

scholarly journals Galaxy rotation curves using a non-parametric regression method: core, cuspy and fuzzy scalar field dark matter models

2019 ◽  
Vol 488 (4) ◽  
pp. 5127-5144 ◽  
Author(s):  
Lizbeth M Fernández-Hernández ◽  
Ariadna Montiel ◽  
Mario A Rodríguez-Meza
Keyword(s):  
Dark Matter ◽  
Selection Criteria ◽  
Spiral Galaxies ◽  
Information Criterion ◽  
Volume Density ◽  
Rotation Curves ◽  
Fuzzy Models ◽  
Galaxy Rotation Curves ◽  
Statistical Criteria ◽  
Non Parametric

ABSTRACT We present a non-parametric reconstruction of the rotation curves (RCs) for 88 spiral galaxies using the LOESS (locally weighted scatterplot smoothing) + SIMEX (simulation and extrapolation) technique. In order to compare methods, we also use a parametric approach, assuming core and cuspy dark matter (DM) profiles: pseudo-isothermal (PISO), Navarro−Frenk–White (NFW), Burkert, Spano, the soliton, and two fuzzy soliton + NFW. As a result of these two approaches, a comparison of the RCs obtained is carried out by computing the distance between the central curves and the distance between the 1σ error bands. Furthermore, we perform a model selection according to two statistical criteria, the Bayesian information criterion and the value of $\chi ^2_{\rm red}$. We work with two groups. The first is a comparison between PISO, NFW, Spano and Burkert, showing that Spano is the most favoured model satisfying our selection criteria. For the second group, we select the soliton, NFW and fuzzy models, resulting in soliton as the best model. Moreover, according to the statistical tools and non-parametric reconstruction, we are able to classify galaxies as core or cuspy. Finally, using a Markov chain Monte Carlo method, for each of the DM models we compute the characteristic surface density, μDM = ρsrs, and the mass within 300 pc. We find that there is a common mass for spiral galaxies of the order of 107 M⊙, which is in agreement with results for dSph Milky Way satellites, independent of the model. This result is also consistent with our finding that there is a constant characteristic volume density of haloes. Finally, we also find that μDM is not constant, which is in tension with the literature.

scholarly journals Cores vs. Cusps: Dark Matter Density Profiles in Spirals

2004 ◽  
Vol 220 ◽  
pp. 311-312
Author(s):  
Gianfranco Gentile ◽  
Uli Klein ◽  
Paolo Salucci ◽  
Daniela Vergani
Keyword(s):  
Dark Matter ◽  
Rotation Curve ◽  
Spiral Galaxies ◽  
Matter Density ◽  
Matter Distribution ◽  
Rotation Curves ◽  
Density Profiles ◽  
The Core ◽  
Dark Matter Distribution ◽  
A New Technique

We use photometric, Hα and Hi data to investigate the distribution of dark matter in spiral galaxies. A new technique for deriving the Hi rotation curve is presented. the final combined Hα+Hi rotation curves are symmetric, well resolved and extend to large radii. We perform the rotation curve decomposition into the luminous and dark matter contributions. the observations are confronted with different models of the dark matter distribution, including core-dominated and cusp-dominated halos as well as less conventional possibilities. the best agreement with the observations is found for the core-dominated halos.

scholarly journals Constraints on the Dark Matter from Optical Rotation Curves

1987 ◽  
Vol 117 ◽  
pp. 51-65 ◽  
Author(s):  
Vera C. Rubin
Keyword(s):  
Dark Matter ◽  
Spiral Galaxies ◽  
Optical Rotation ◽  
Optical Image ◽  
Rotation Curves

From the observed rotation curves of Sa, Sb, and Sc spiral galaxies, it is possible to deduce a dozen constraints on the nonluminous matter in spirals. Within the optical image, the dark matter is less concentrated than the luminous, and contributes about 1/2 of the mass, for spirals of all Hubble types and luminosities.

scholarly journals Tidal Dwarf Galaxies and Missing Baryons

2010 ◽  
Vol 2010 ◽  
pp. 1-7 ◽  
Author(s):  
Frederic Bournaud
Keyword(s):  
Dark Matter ◽  
Spiral Galaxies ◽  
Dwarf Galaxies ◽  
High Redshift ◽  
Rotation Curves ◽  
Cosmological Problem ◽  
Flat Rotation Curves ◽  
Mass Size ◽  
Merger Rate ◽  
The Universe

Tidal dwarf galaxies form during the interaction, collision, or merger of massive spiral galaxies. They can resemble “normal” dwarf galaxies in terms of mass, size, and become dwarf satellites orbiting around their massive progenitor. They nevertheless keep some signatures from their origin, making them interesting targets for cosmological studies. In particular, they should be free from dark matter from a spheroidal halo. Flat rotation curves and high dynamical masses may then indicate the presence of an unseen component, and constrain the properties of the “missing baryons,” known to exist but not directly observed. The number of dwarf galaxies in the Universe is another cosmological problem for which it is important to ascertain if tidal dwarf galaxies formed frequently at high redshift, when the merger rate was high, and many of them survived until today. In this paper, “dark matter” is used to refer to the nonbaryonic matter, mostly located in large dark halos, that is, CDM in the standard paradigm, and “missing baryons” or “dark baryons” is used to refer to the baryons known to exist but hardly observed at redshift zero, and are a baryonic dark component that is additional to “dark matter”.

scholarly journals Vertical Motion and the Thickness of Hi Disks: Implications for Galactic Mass Models

1983 ◽  
Vol 100 ◽  
pp. 69-76
Author(s):  
P. C. van der Kruit ◽  
G. S. Shostak
Keyword(s):  
Dark Matter ◽  
Mass Distribution ◽  
Rotation Curve ◽  
Spiral Galaxies ◽  
Galactic Plane ◽  
Vertical Motion ◽  
Late Type ◽  
Rotation Curves ◽  
Central Bulge ◽  
Local Value

Most studies of the mass distribution in spiral galaxies have been based on the observed rotation curves. A serious ambiguity in this approach has always been that the rotation curve contains in itself no information on the mass distribution in the direction perpendicular to the galactic plane. The usual assumption has been that the mass in late type galaxies is distributed as the light, namely outside the central bulge in a highly flattened disk. In recent years it has been found that the rotation curves decline little or not at all, indicating large increases in the local value of M/L with increasing galactocentric radius (e.g. Bosma and van der Kruit, 1979). On the basis of dynamical arguments involving stability it has been suspected that the material giving rise to the large values of M/L - the “dark matter” - is distributed in the halos of these galaxies, so that the assumption of a flat mass distribution would have to be wrong.

scholarly journals Dissipation and Formation of Galactic Halos

1988 ◽  
Vol 130 ◽  
pp. 421-425
Author(s):  
George R. Blumenthal
Keyword(s):  
Dark Matter ◽  
Mass Distribution ◽  
Spiral Galaxies ◽  
Galactic Halos ◽  
Rotation Curves ◽  
Striking Effect

When protogalaxies collapse, the cooling and infall of what will become the visible galactic component affects the mass distribution of dissipationless dark matter particles which constitute the halo. For spiral galaxies, the reaction of the dissipationless halo can have a striking effect on the resulting rotation curves [1–5].

scholarly journals Rotation curves of 967 spiral galaxies: Implications for dark matter

1995 ◽  
Author(s):  
Massimo Persic ◽  
Paolo Salucci ◽  
Fulvio Stel
Keyword(s):  
Dark Matter ◽  
Spiral Galaxies ◽  
Rotation Curves

scholarly journals Interaction of Disks and Dark Haloes of Dwarf Spirals

1996 ◽  
Vol 171 ◽  
pp. 171-174
Author(s):  
B. Fuchs ◽  
V. Friese ◽  
H. Reffert ◽  
R. Wielen
Keyword(s):  
Dark Matter ◽  
Spiral Galaxies ◽  
Rotation Curves

In a number of dwarf spiral galaxies the HI-emission has been studied with sufficient resolution to derive the rotation curves of the galaxies. These show that the disks of dwarf spirals are imbedded in extended haloes of dark matter, quite similar to the disks of giant spiral galaxies.

scholarly journals Do All Spiral Galaxies Have a Massive Dark Halo?

1999 ◽  
Vol 183 ◽  
pp. 157-157 ◽  
Author(s):  
M. Honma ◽  
Y. Sofue
Keyword(s):  
Dark Matter ◽  
Spiral Galaxies ◽  
The Other ◽  
Dark Halo ◽  
Rotation Curves ◽  
Other Hand ◽  
Flat Rotation Curves ◽  
The Masses ◽  
Scale Length

We have investigated the masses and extents of dark halos of spiral galaxies by two methods. First, we have reanalyzed HI outer rotation curves so far obtained considering the velocity uncertainties. We confirmed that many HI rotation curves indicate the existence of dark matter to some extent. However, we also found that only few rotation curves provide direct evidences for halos extended beyond 10 disk scale length. On the other hand, recent HI observations revealed that several galaxies have declining rotation curves that are approximated by Keplerian in the outermost regions. Considering the velocity uncertainties in the outer rotation curves, we found that these declining rotation curves are not rare compared to flat rotation curves. If these declining rotation curves indeed trace the mass truncation, these results indicate that some dark halos have moderate masses that are comparable or slightly larger than disk masses.

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