The Structure of the Outer Halo of the Galaxy and its Relationship to Nearby Large-Scale Structure

The Small and Large Magellanic Clouds (SMC, LMC) are of considerable interest from a kinematical viewpoint. The tidal interation of the Clouds with each other and with the Galaxy appears to have been quite significant in recent times (Murai & Fujimoto 1980). The SMC in particular appears to have been considerably disrupted by a recent close passage to the LMC (Mathewson & Ford 1984, Mathewson 1984, Mathewson et al. 1986). For the LMC Freeman et al. (1983) found that the young and old populations have significantly different rotation solutions.Planetary Nebulae (PN) form a population with age intermediate between the HI and young clusters and the old Population II clusters. A large number of PN are known in the MCs. Sanduleak et al. (1978) compiled a list of 102 in the LMC and 28 in the SMC. Since then other authors have increased the total number known to approximately 140 in the LMC and 50 in the SMC.

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Distribution of CO in the Southern Milky Way and large-scale structure in the Galaxy

Symposium - International Astronomical Union ◽

10.1017/s0074180900242435 ◽

1985 ◽

Vol 106 ◽

pp. 203-204

Author(s):

W.H. Mccutcheon ◽

B. J. Robinson ◽

R. N. Manchester ◽

J. B. Whiteoak

Keyword(s):

Large Scale ◽

Milky Way ◽

Galactic Plane ◽

Large Scale Structure ◽

Sampling Interval ◽

Scale Structure ◽

Plane Region ◽

The Galaxy ◽

Csiro Division

The southern galactic-plane region, in the ranges 294° ≤ 1 ≤ 358°, −0°.075 ≤ b ≤ 0°.075, has been surveyed in the J = 1–0 line of 12CO with a sampling interval of 3′ arc. Observations were made with the 4-metre telescope at the CSIRO Division of Radiophysics in 1980 and 1981. Details of equipment and observing procedure are given in Robinson et al. (1982, 1983); see also McCutcheon et al. (1983).

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The Local Large-Scale Structure from HIPASS

Symposium - International Astronomical Union ◽

10.1017/s0074180900196639 ◽

2005 ◽

Vol 216 ◽

pp. 196-202

Author(s):

Martin Zwaan ◽

Martin Meyer ◽

Rachel Webster ◽

Lister Staveley-Smith

Keyword(s):

Large Scale ◽

Large Scale Structure ◽

Scale Structure ◽

Sky Survey ◽

The Galaxy ◽

Point Correlation ◽

Point Correlation Function ◽

Fisher Relation ◽

Galaxy Population ◽

Mass Functions

The HI Parkes All Sky Survey (HIPASS) offers a unique perspective on the galaxy population in the local universe. A catalogue of 4315 HI-selected galaxies has been extracted from the southern region of the survey (δ < +2°). This catalogue gives a clear view of the local large-scale structure and is used to study the two-point correlation function, the Tully-Fisher relation, and galaxy luminosity and mass functions. Some initial results are discussed here.

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The Large-Scale Radio Continuum Structure of Spiral Galaxies

Symposium - International Astronomical Union ◽

10.1017/s0074180900143645 ◽

1978 ◽

Vol 77 ◽

pp. 33-48 ◽

Cited By ~ 1

Author(s):

P.C. van der Kruit

Keyword(s):

Large Scale ◽

Spiral Galaxies ◽

Large Scale Structure ◽

Scale Structure ◽

Optical Image ◽

Radio Continuum ◽

Continuum Emission ◽

The Galaxy ◽

Continuum Structure ◽

Disk Component

This review concerns the large-scale structure of radio continuum emission in spiral galaxies (“the smooth background”), by which we mean the distribution of radio surface brightness at scales larger than, say, 1 kpc. Accordingly the nuclear emission and structure due to spiral arms and HII regions will not be a major topic of discussion here. Already the first mappings of the galactic background suggested that there is indeed a distribution of radio continuum emission extending throughout the Galaxy. This conclusion has been reinforced by the earliest observations of M31 by showing that the general emission from this object extended over at least the whole optical image. More recently, van der Kruit (1973a, b, c) separated the radio emission from a sample of spiral galaxies observed at 1415 MHz with the Westerbork Synthesis Radio Telescope (WSRT) into a nuclear, spiral arm and “base disk” component, showing that the latter component usually contains most of the flux density. This latter component is largely non-thermal and extends over the whole optical image (see also van der Kruit and Allen, 1976). Clearly it is astrophysically interesting to discuss the large-scale structure of the radio continuum emission.

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Large-Scale Structure of the Galaxy and High-Energy Gamma-Ray Observations

Galactic Astrophysics and Gamma-Ray Astronomy ◽

10.1007/978-94-009-7208-7_15 ◽

1983 ◽

pp. 223-247 ◽

Cited By ~ 1

Author(s):

H. A. Mayer-Hasselwander

Keyword(s):

Large Scale ◽

Gamma Ray ◽

Large Scale Structure ◽

High Energy ◽

Scale Structure ◽

High Energy Gamma ◽

The Galaxy ◽

Energy Gamma

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Web of the giant: Spectroscopic confirmation of a large-scale structure around the z = 6.31 quasar SDSS J1030+0524

Astronomy and Astrophysics ◽

10.1051/0004-6361/202039045 ◽

2020 ◽

Vol 642 ◽

pp. L1

Author(s):

Marco Mignoli ◽

Roberto Gilli ◽

Roberto Decarli ◽

Eros Vanzella ◽

Barbara Balmaverde ◽

...

Keyword(s):

Black Hole ◽

Large Scale ◽

Large Scale Structure ◽

Scale Structure ◽

Solar Mass ◽

Massive Black Holes ◽

Lyman Alpha ◽

Peculiar Velocities ◽

The Galaxy ◽

Lyman Alpha Emitters

We report on the spectroscopic confirmation of a large-scale structure around the luminous z = 6.31 quasi-stellar object (QSO) SDSS J1030+0524, powered by a one billion solar mass black hole. The structure is populated by at least six members, namely, four Lyman-break galaxies (LBGs), and two Lyman alpha emitters (LAEs). The four LBGs were identified among a sample of 21 i-band dropouts with zAB < 25.5 selected up to projected separations of 5 physical Mpc (15 arcmin) from the QSO. Their redshifts were determined through multi-object spectroscopic observations at 8−10 m class telescopes lasting up to eight hours. The two LAEs were identified in a 6 h VLT/MUSE observation centered on the QSO. The redshifts of the six galaxies cover the range between 6.129−6.355. Assuming that the peculiar velocities are negligible, this range corresponds to radial separations of ±5 physical Mpc from the QSO, that is comparable to the projected scale of the observed LBG distribution on the sky. We conservatively estimate that this structure is significant at a level > 3.5σ and that the level of the galaxy overdensity is at least 1.5−2 within the large volume sampled (∼780 physical Mpc3). The spectral properties of the six member galaxies (Lyα strength and UV luminosity) are similar to those of field galaxies at similar redshifts. This is the first spectroscopic identification of a galaxy overdensity around a supermassive black hole in the first billion years of the Universe. Our finding lends support to the idea that the most distant and massive black holes form and grow within massive (>1012 M⊙) dark matter halos in large-scale structures and that the absence of earlier detections of such systems is likely due to observational limitations.

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Mapping the Large-Scale Structure

Symposium - International Astronomical Union ◽

10.1017/s0074180900048348 ◽

1994 ◽

Vol 161 ◽

pp. 669-686

Author(s):

V. de Lapparent

Keyword(s):

Large Scale ◽

Background Radiation ◽

Theoretical Models ◽

Large Scale Structure ◽

Scale Structure ◽

Nearby Galaxy ◽

Redshift Surveys ◽

Galaxy Distribution ◽

The Galaxy ◽

Microwave Background Radiation

The nearby galaxy distribution suggests a remarkable structure in which large voids are delineated by dense walls of galaxies in a cell-like pattern. The nearby voids range in diameter from ∼ 10 to ∼ 50h− 1 Mpc. Deeper surveys appear to be consistent with the nearby distribution and show no evidence of voids larger than ∼ 100h −1 ∗ Mpc. We might thus have reached the scale where the universe becomes homogeneous. The size of the largest inhomogeneities in the galaxy distribution is an important issue because it can put tight constraints on the theoretical models when confronted by the high degree of isotropy of the microwave background radiation. Comparison of the various existing redshift surveys emphasizes the need for systematic redshift surveys over significant areas of the sky out to intermediate and large distances. Although deep pencil-beam surveys are best suited for probing a large number of voids and walls, understanding the nature of the intercepted peaks and valleys in terms of large-scale structure requires that the angular coverage of the surveys be larger than the galaxy auto-correlation length. If this condition is not satisfied, the size of the voids and the density contrast of the walls can be overestimated.

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