# Constraining the Magnetic Effects on H I Rotation Curves and the Need for Dark Halos

@article{SnchezSalcedo2004ConstrainingTM,
title={Constraining the Magnetic Effects on H I Rotation Curves and the Need for Dark Halos},
author={F. Javier S{\'a}nchez-Salcedo and Mauricio Reyes-Ruiz},
journal={The Astrophysical Journal},
year={2004},
volume={607},
pages={247-257}
}
• Published 2 February 2004
• Physics
• The Astrophysical Journal
The density profiles of dark halos are usually inferred from the rotation curves of disk galaxies based on the assumption that the gas is a good tracer of the gravitational potential of the galaxies. Some authors have suggested that magnetic pinching forces could alter significantly the rotation curves of spiral galaxies. In contrast to other studies that have concentrated on the vertical structure of the disk, here we focus on the problem of magnetic confinement in the radial direction to… Expand
12 Citations
Magnetic fields: Impact on the rotation curve of the Galaxy
• Physics
• 2013
We quantify the effects of magnetic fields, cosmic rays and gas pressure on the rotational velocity of HI gas in the Milky Way, at galactic distances between Rsun and 2Rsun. The magnetic field isExpand
The thickness of H i in galactic discs under MOdified Newtonian Dynamics: theory and application to the Galaxy
• Physics
• 2007
The outskirts of galaxies are a very good laboratory for testing the nature of the gravitational field at low accelerations. By assuming that the neutral hydrogen gas is in hydrostatic equilibrium inExpand
THE DARK HALO OF NGC 5963 AS A CONSTRAINT ON DARK MATTER SELF-INTERACTION AT THE LOW-VELOCITY REGIME
Self-interacting dark matter has been proposed as a hypothesis to explain the shallow central slopes of the density profiles of dark matter halos in galaxies. In order to be consistent withExpand
On the origin of warps and the role of the intergalactic medium
There is still no consensus as to what causes galactic discs to become warped. Successful models should account for the frequent occurrence of warps in quite isolated galaxies, their amplitude asExpand
Are rotation curves in NGC 6946 and the Milky Way magnetically supported
The inner disk rotation of NGC 6946 and the Milky Way is dominated by gravity but magnetism is not negligible at radii where the rotation curve becomes flat, and indeed could become dominant at veryExpand
Global disk model for galaxies NGC 1365, NGC 6946, NGC 7793, UGC 6446
• Physics
• 2009
Spiral galaxies are studied using a simple global disc model as a means for approximate determination of mass profiles. Based on rotation curves and the amount of gas (HI+He), we find global surfaceExpand
Global Three-dimensional Magentohydrodynamic Simulations of Galactic Gaseous Disks. I. Amplification of Mean Magnetic Fields in an Axisymmetric Gravitational Potential
• Physics
• 2006
We carried out global three-dimensional resistive magnetohydrodynamic simulations of galactic gaseous disks to investigate how the galactic magnetic fields are amplified and maintained. We adopt aExpand
Magnetic fields in the galactic Universe, as observed in supershells, galaxies, intergalactic and cosmic realms
Abstract Here I present a survey of magnetic fields in large objects, from the interstellar supershells (10 pc) up to the edge of the Universe (near a redshift z of 10), with an emphasis onExpand
Galaxy rotation curves: the effect of $\vec{j} \times\vec{B}$ force
Using the Galaxy as an example, we study the effect of $\vec{j} \times \vec{B}$ force on the rotational curves of gas and plasma in galaxies. Acceptable model for the galactic magnetic field andExpand
Astrophysics in 2004
• Physics
• 2005
In this 14th edition of ApXX, 1 we bring you the Sun (§ 2) and Stars (§ 4), the Moon and Planets (§ 3), a truly binary pulsar (§ 5), a kinematic apology (§ 6), the whole universe (§§ 7 and 8),Expand

#### References

SHOWING 1-10 OF 53 REFERENCES
On the role of magnetic fields in H I rotation curves
The importance of large-scale magnetic fields in H I rotation curves of spiral galaxies is investigated. In contrast to other papers that try to render dark matter unnecessary, we assume thatExpand
The Structure of cold dark matter halos
• Physics
• 1996
High resolution N-body simulations show that the density profiles of dark matter halos formed in the standard CDM cosmogony can be fit accurately by scaling a simple “universal” profile. RegardlessExpand
Magnetic fields as an alternative explanation for the rotation curves of spiral galaxies
• Physics
• Nature
• 1992
THE flat rotation curves of spiral galaxies are usually regarded as the most convincing evidence for dark matter. The assumption that gravity alone is responsible for the motion of gas beyond theExpand
The Evolution of a Primordial Galactic Magnetic Field
• Physics
• 1997
We consider the hypothesis that galactic magnetic fields are primordial. We also discuss the various objections to this hypothesis. To test this hypothesis properly we assume that there was aExpand
Simulating observations of dark matter dominated galaxies: towards the optimal halo profile
Low surface brightness galaxies are dominated by dark matter, and their rotation curves thus reflect their dark matter distribution. Recent high-resolution rotation curves suggest that their darkExpand
Neutral Hydrogen in the Outer Galaxy
• Physics
• 1991
The H I 21 cm emission-line survey data of Stark et al. (1991) have been used to study the distribution of H I in the outer Galaxy and to improve understanding of the various systematic problemsExpand
Where Do the Disks of Spiral Galaxies End
• Physics
• 1997
In spiral galaxies, the H I surface density declines with increasing radius to a point at which it is seen to truncate dramatically in the best observed cases. If the ambient radiation field isExpand
The Density Profile of the Dark Matter Halo of NGC 4605
• Physics
• 2001
We have obtained ~100 pc resolution CO and ~60 pc resolution Halpha observations of the dwarf spiral galaxy NGC 4605. We use them to derive a high resolution rotation curve and study the centralExpand
At the low-mass end - Light and H I distribution of GR 8
• Physics
• 1990
The dwarf irregular galaxy GR 8, which is at the extreme faint end of the luminosity and mass functions, is studied using optical photometry and 21 cm H I line observations. For the lightExpand
The angular momentum content of dwarf galaxies: new challenges for the theory of galaxy formation
• Physics
• 2001
We compute the specific angular momentum distributions for a sample of low-mass disc galaxies observed by Swaters. We compare these distributions to those of dark matter haloes obtained by Bullock etExpand