Distribution of Dark Matter in Polar Ring Galaxies

Abstract We study the formation of polar ring galaxies via minor mergers. We used N-body+hydrodynamics simulations to reproduce the dynamics of the observed system AM 2229-735 that is a minor merger whose interaction signals are those of a progenitor for a polar ring galaxy. We used the observational information of the system to get initial conditions for the orbit and numerical realisations of the galaxies to run the simulations. Our simulations reproduce the global characteristics of interaction observed in the system such as arms and a material bridge connecting the galaxies. As a merger remnant, we found a quasi-stable and self gravitating planar tidal stream with dark matter, stars and gas orbiting in a plane approximately perpendicular to the main galaxy disk leading in the future to a polar ring galaxy. We studied the dynamical conditions of the polar structure and found evidence suggesting that this kind of merger remnant can settle down in a disk-like structure with isothermal support, providing inspiring evidence about the process of formation of galactic disks and providing a potentially independent scenario to study the presence of dark matter in this kind of galaxies.

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Dark Matter in the Polar Ring Spiral NGC 660

Symposium - International Astronomical Union ◽

10.1017/s0074180900109489 ◽

1995 ◽

Vol 164 ◽

pp. 435-435

Author(s):

Wim Van Driel

Keyword(s):

Dark Matter ◽

Three Dimensional ◽

Polar Ring ◽

Ring Galaxies ◽

Dimensional Distribution

Polar ring galaxies, where rotation velocities can be measured in two orthogonal planes, are generally considered to be ideal objects for studies of the three-dimensional distribution of dark matter in galaxies.

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9. The Outer Galactic Environment

Transactions of the International Astronomical Union ◽

10.1017/s0251107x00007288 ◽

1988 ◽

Vol 20 (01) ◽

pp. 396-404

Keyword(s):

Dark Matter ◽

Galactic Plane ◽

Dwarf Galaxies ◽

Single System ◽

Narrow Strip ◽

Polar Ring ◽

Ring Galaxies

One of the highlights of the study of the galactic environment is the demonstration that companions and hydrogen clouds surrounding our Galaxy form a ring-like structure similar to that surrounding external polar-ring galaxies. Probably this feature is common in giant galaxies. Dwarf galaxies may possess their own dark coronas, which fact, if confirmed, puts severe constraints on the nature of dark matter. Available evidence confirms earlier suggestions that our Galaxy with its massive corona, companions, and surrounding gas forms a single system with many mutual interactions. Most companions of our Galaxy as well as the main hydrogen streams are located in a narrow strip inclined 70° to the galactic plane.

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Distribution of Dark Matter in Polar Ring Galaxies

Symposium - International Astronomical Union ◽

10.1017/s0074180900150429 ◽

1987 ◽

Vol 117 ◽

pp. 315-315

Author(s):

Bradley C. Whitmore ◽

Douglas B. McElroy ◽

François Schweizer ◽

Vera C. Rubin

Keyword(s):

Dark Matter ◽

Gravitational Potential ◽

Three Dimensions ◽

Polar Ring ◽

Ring Galaxies ◽

Spherical Potential

The discovery of SO galaxies with polar rings makes it possible to directly measure the gravitational potential of a galaxy in three dimensions. Schweizer, Whitmore and Rubin (1983) find a spherical potential in the case of A0136-0801. We have observed three more polar ring galaxies using the 4 meter telescope at CTIO. The following table summarizes the results for these three systems as well as A0136-0801, and figure 1 shows an example of the data.

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Structure and Kinematics of Polar Ring Galaxies: New Observations and Estimation of the Dark Halo Shape

Open Astronomy ◽

10.1515/astro-2017-0205 ◽

2015 ◽

Vol 24 (1) ◽

Cited By ~ 1

Author(s):

A. Moiseev ◽

S. Khoperskov ◽

A. Khoperskov ◽

K. Smirnova ◽

A. Smirnova ◽

...

Keyword(s):

Dark Matter ◽

Observational Data ◽

Dark Matter Halo ◽

Dark Halo ◽

Dark Matter Halos ◽

Ionized Gas ◽

Polar Ring ◽

Gas Kinematics ◽

Open Questions ◽

Ring Galaxies

AbstractThe polar ring galaxies (PRGs) represent an interesting type of peculiar systems in which the outer matter is rotating in the plane which is roughly perpendicular to the disk of the main galaxy. Despite the long-lasting study of the PRGs, the amount of observational data detailed enough is insufficient; there still remain many open questions. Among the most interesting issues, there are: estimating the flattening of dark matter halos in these systems and verifying the assumption that the most massive polar structures were formed by accretion of the matter from intergalactic filaments. The new catalog recently compiled by our team using SDSS images increased, by several times, the number of known PRGs. The current paper gives an overview of our latest results on the study of morphological and photometric structure of the PRGs. Using the stellar and ionized gas kinematics data based on spectroscopic observations with the Russian 6-m telescope, we estimate the shape of dark matter halo in individual galaxies.

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Dust and infrared imaging of polar ring galaxies

Planetary and Space Science ◽

10.1016/0032-0633(95)00053-8 ◽

1995 ◽

Vol 43 (10-11) ◽

pp. 1377-1388 ◽

Cited By ~ 10

Author(s):

M. Arnaboldi ◽

K.C. Freeman ◽

P.D. Sackett ◽

L.S. Sparke ◽

M. Capaccioli

Keyword(s):

Infrared Imaging ◽

Polar Ring ◽

Ring Galaxies

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The Polar-Ring Galaxies NGC 2685 and NGC 3808B (W 300)

International Astronomical Union Colloquium ◽

10.1017/s0252921100005157 ◽

1990 ◽

Vol 124 ◽

pp. 231-244

Author(s):

V. P. Reshetnikov ◽

V. A. Yakovleva

Keyword(s):

Intergalactic Medium ◽

Close Encounter ◽

Main Body ◽

Polar Plane ◽

Polar Ring ◽

Ring Galaxies ◽

Companion Galaxy ◽

Peculiar Galaxies

Polar-ring galaxies (PRG) are among the most interesting examples of interaction between galaxies. A PRG is a galaxy with an elongated main body surrounded by a ring (or a disk) of stars, gas, and dust rotating in a near-polar plane (Schweizer, Whitmore, and Rubin, 1983). Accretion of matter by a massive lenticular galaxy from either intergalactic medium or a companion galaxy is usually considered as an explanation of the observed structure of PRG. In the latter case there are two possibilities: (1) capture and merging of a neighbor galaxy, and (2) accretion of mass from a companion galaxy during a close encounter. Two PRG formation scenarios just mentioned are illustrated here by the results of our observations of the peculiar galaxies NGC 2685 and NGC 3808B.

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