The Development of Gas/Star Offsets in Tidal Tails

Mihos, J. Christopher

doi:10.1086/319721

Cited by 44 publications

(47 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Despite the insistence that stars should have been stripped off with the gas in the tidal models, the observations show that stellar tails are often completely missing or offset from the gaseous tails in interacting systems (e.g., the M82 group; Yun et al 1994;Hibbard, Vacca & Young 2000), and this can be reproduced in simulations (Barnes 2002). This is especially true when the galaxy's initial gas distribution is more extended than the stellar component (Mihos 2001;Yoshizawa 1998;Li 1999), a common situation (Broeils & van Woerden 1994). The possibility of an offset stellar stream made up of old stars also still exists (Majewski et al 1999;van der Marel & Roeland 2001).…”

Section: Origin Of the Streammentioning

confidence: 96%

The Magellanic Stream, High‐Velocity Clouds, and the Sculptor Group

Putman

Staveley‐Smith

Freeman

et al. 2003

ApJ

291

401

View full text Add to dashboard Cite

The Magellanic Stream is a 100 Â 10 filament of gas that lies within the Galactic halo and contains $2 Â 10 8 M of neutral hydrogen. In this paper we present data from the H i Parkes All Sky Survey (HIPASS) in the first complete survey of the entire Magellanic Stream and its surroundings. We also present a summary of the reprocessing techniques used to recover large-scale structure in the Stream. The substantial improvement in spatial resolution and angular coverage compared to previous surveys reveals a variety of prominent features, including bifurcation along the main Stream filament; dense, isolated clouds that follow the entire length of the Stream; head-tail structures; and a complex filamentary web at the head of the Stream where gas is being freshly stripped away from the Small Magellanic Cloud and the Bridge. Debris that appears to be of Magellanic origin extends out to 20 from the main Stream filaments. The Magellanic Stream has a velocity gradient of 700 km s À1 from the Clouds to the tail of the Stream, $390 km s À1 greater than that due to Galactic rotation alone, therefore implying a noncircular orbit. The dual filaments comprising the Stream are likely to be relics from gas stripped separately from the Magellanic Bridge and the SMC. This implies that (1) the Bridge is somewhat older than conventionally assumed; and (2) the Clouds have been bound together for at least one or two orbits. The transverse velocity gradient of the Stream also appears to support long-term binary motion of the Clouds. A significant number of the most elongated cataloged Stream clouds (containing $1% of the Stream mass) have position angles aligned along the Stream. This suggests the presence of shearing motions within the Stream, arising from tidal forces or interaction with the tenuous Galactic halo. As previously noted, clouds within one region of the Stream, along the sight line to the less distant half (southern half on the sky) of the Sculptor Group, show anomalous properties. There are more clouds along this sight line than any other part of the Stream, and their velocity distribution significantly deviates from the gradient along the Stream. We argue that this deviation could be due to a combination of halo material, and not to distant Sculptor clouds, based on a spatial and kinematic comparison between the Sculptor Group galaxies and the anomalous clouds and the lack of cloud detection in the northern half of the group. This result has significant implications for the hypothesis that there might exist distant, massive high-velocity clouds within the Local Group. Cataloged clouds within the Magellanic Stream do not have a preferred scale size. Their mass spectrum f ðM H i Þ / M À2:0 H i and column density spectrum f ðN H i Þ / N À2:8 H i are steep compared with Ly absorbers and galaxies, and similar to the anomalous clouds along the Sculptor Group sight line.

show abstract

Section: Origin Of the Streammentioning

confidence: 96%

The Magellanic Stream, High‐Velocity Clouds, and the Sculptor Group

Putman

Staveley‐Smith

Freeman

et al. 2003

ApJ

291

401

View full text Add to dashboard Cite

show abstract

“…Hibbard & Yun, 1999) or additional processes that act on one component and not the other. For instance, ram pressure due to the interaction with the intergalactic medium might strip the HI gas further away (Mihos, 2001). Meanwhile, blind HI surveys have disclosed the presence of numerous intergalactic, filamentary, HI structures apparently devoid of stars (see the review by Briggs, 2004, and references therein).…”

Section: When Components Are Missing: Hi Without Optical Counterpartsmentioning

confidence: 99%

Tides in Colliding Galaxies

Duc

Renaud

2013

Lecture Notes in Physics

View full text Add to dashboard Cite

Long tails and streams of stars are the most noticeable upshots of galaxy collisions. Their origin as gravitational, tidal, disturbances has however been recognized only less than fifty years ago and more than ten years after their first observations. This Review describes how the idea of galactic tides emerged, in particular thanks to the advances in numerical simulations, from the first ones that included tens of particles to the most sophisticated ones with tens of millions of them and state-of-the-art hydrodynamical prescriptions. Theoretical aspects pertaining to the formation of tidal tails are then presented. The third part of the review turns to observations and underlines the need for collecting deep multi-wavelength data to tackle the variety of physical processes exhibited by collisional debris. Tidal tails are not just stellar structures, but turn out to contain all the components usually found in galactic disks, in particular atomic / molecular gas and dust. They host star-forming complexes and are able to form star-clusters or even second-generation dwarf galaxies. The final part of the review discusses what tidal tails can tell us (or not) about the structure and content of present-day galaxies, including their dark components, and explains how tidal tails may be used to probe the past evolution of galaxies and their mass assembly history. On-going deep wide-field surveys disclose many new lowsurface brightness structures in the nearby Universe, offering great opportunities for attempting galactic archeology with tidal tails.

show abstract

“…Mihos 2001). On the other hand, though the projected image rules out that NGC 4262 is a classical polar ring galaxy (i.e.…”

Section: Introductionmentioning

confidence: 99%

NGC 4262: a Virgo galaxy with an extended ultraviolet ring

Bettoni

Buson

Galletta³

2010

A&A

View full text Add to dashboard Cite

Context. The Galaxy Ultraviolet Explorer (GALEX) satellite has recently shown the presence of an extended, outer ring studded with UV-bright knots surrounding the lenticular galaxy NGC 4262. Such a structure-not detected in the optical-is coupled with a ring of atomic (HI) gas. Aims. We want to show that both star-forming and HI rings surrounding this SB0 galaxy share the same radial distance from the galaxy center and spatial orientation. We also model the kinematics of the ring(s) and of the galaxy body. Methods. We make use of archive FUV and NUV GALEX data plus HI observations from the literature. Results. We confirm that the UV-bright and atomic gas rings of NGC 4262 have the same extent and projected spatial orientation. Their kinematics is not coupled with that of the galaxy stars. Conclusions. It is possible that NGC 4262 has undergone a major gas stripping event in the past that was the origin of the present "necklace" of UV-bright knots.

show abstract

The Development of Gas/Star Offsets in Tidal Tails

Cited by 44 publications

References 29 publications

The Magellanic Stream, High‐Velocity Clouds, and the Sculptor Group

The Magellanic Stream, High‐Velocity Clouds, and the Sculptor Group

Tides in Colliding Galaxies

NGC 4262: a Virgo galaxy with an extended ultraviolet ring

Contact Info

Product

Resources

About