Spin Alignment in Analogues of The Local Sheet

AbstractTidal torque theory and simulations of large scale structure predict spin vectors of massive galaxies should be coplanar with sheets in the cosmic web. Recently demonstrated, the giants (Ks⩽ -22.5 mag) in the Local Volume beyond the Local Sheet have spin vectors directed close to the plane of the Local Supercluster, supporting the predictions of Tidal Torque Theory. However, the giants in the Local Sheet encircling the Local Group display a distinctly different arrangement, suggesting that the mass asymmetry of the Local Group or its progenitor torqued them from their primordial spin directions. To investigate the origin of the spin alignment of giants locally, analogues of the Local Sheet were identified in the SDSS DR9. Similar to the Local Sheet, analogues have an interacting pair of disk galaxies isolated from the remaining sheet members. Modified sheets in which there is no interacting pair of disk galaxies were identified as a control sample.Galaxies in face-on control sheets do not display axis ratios predominantly weighted toward low values, contrary to the expectation of tidal torque theory. For face-on and edge-on sheets, the distribution of axis ratios for galaxies in analogues is distinct from that in controls with a confidence of 97.6% & 96.9%, respectively. This corroborates the hypothesis that an interacting pair can affect spin directions of neighbouring galaxies.

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The Physical Properties of Large Scale Systems from Optical Observations

Symposium - International Astronomical Union ◽

10.1017/s0074180900144638 ◽

1978 ◽

Vol 79 ◽

pp. 253-262

Author(s):

G. O. Abell

Keyword(s):

Physical Properties ◽

Large Scale ◽

Local Group ◽

Optical Observations ◽

Local Inhomogeneity ◽

Large Scale Systems ◽

Local Supercluster

Holmberg's (1937) analysis of the distribution of double and multiple galaxies provided what may have been the first hint of a local inhomogeneity of greater scale than that of the Local Group. the idea of a Local Supercluster was subsequently revived by de Vaucouleurs (1953, 1956, 1958). the analyses of others, as well as the continuing study of de Vaucouleurs himself (1976 and references cited therein) have now effectively established the reality of the Local Supercluster. Several other more remote inhomogeneities, or “clouds” of galaxies, were described by Shane and Wirtanen (1954). the writer (Abell 1958) found the distribution of rich clusters to be clumpy, and published a finding list of several apparent superclusters (Abell 1961).

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The Local Supercluster

Symposium - International Astronomical Union ◽

10.1017/s0074180900144572 ◽

1978 ◽

Vol 79 ◽

pp. 205-213 ◽

Cited By ~ 1

Author(s):

G. de Vaucouleurs

Keyword(s):

Small Groups ◽

Large Scale ◽

Local Group ◽

Virgo Cluster ◽

General Phenomenon ◽

Quantitative Evidence ◽

Present Concept ◽

Local Supercluster ◽

Density Excess

The first quantitative evidence for a large scale density excess or “metagalactic cloud” including the Local Group was obtained by Holmberg (1937) and confirmed by Reiz (1941). the present concept of the Local Supercluster (LSC) as a flattened aggregate of field galaxies, small groups and larger clouds centered at the Virgo cluster was formulated 25 years ago (de Vaucouleurs 1953) even before large-scale superclustering was recognized as a general phenomenon. See review papers in Vistas in Astronomy (1956), Soviet Astronomy (1960), Science (1970), Publ. Astron. Soc. Pacific (1971), and IAU Symp. No. 63 (Abell 1974).

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X-ray Haloes and Cooling Flows

Symposium - International Astronomical Union ◽

10.1017/s0074180900089130 ◽

1991 ◽

Vol 144 ◽

pp. 237-244

Author(s):

A.C. Fabian

Keyword(s):

Large Scale ◽

Local Group ◽

Gas Flows ◽

Disk Galaxies ◽

Intracluster Medium ◽

Early Type ◽

X Ray ◽

Cooling Flows ◽

Hot Gas ◽

Diffuse Medium

The properties of hot gaseous haloes in massive early-type galaxies are briefly reviewed. Gas flows in such haloes are complex yet so large-scale that they may guide us in the understanding of flows around disk galaxies. The intracluster medium is discussed as a further illustration of the properties of diffuse hot gas trapped in a gravtational well. Finally, the possibility of the existence of a significant diffuse medium in the Local Group, and in groups in general, is revived. Such a medium would generate a substantial disk-halo interaction with our Galaxy.

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AGN in dwarf galaxies: frequency, triggering processes and the plausibility of AGN feedback

Monthly Notices of the Royal Astronomical Society Letters ◽

10.1093/mnrasl/slz102 ◽

2019 ◽

Vol 489 (1) ◽

pp. L12-L16 ◽

Cited By ~ 16

Author(s):

Sugata Kaviraj ◽

Garreth Martin ◽

Joseph Silk

Keyword(s):

Galaxy Evolution ◽

Dwarf Galaxy ◽

Control Sample ◽

Galactic Nuclei ◽

Wide Field ◽

Massive Galaxies ◽

Duty Cycles ◽

Key Drivers ◽

Massive Galaxy ◽

Infrared Data

Abstract While active galactic nuclei (AGN) are considered to be key drivers of the evolution of massive galaxies, their potentially significant role in the dwarf-galaxy regime (M* < 109 M⊙) remains largely unexplored. We combine optical and infrared data, from the Hyper Suprime-Cam (HSC) and the Wide-field Infrared Explorer, respectively, to explore the properties of ∼800 AGN in dwarfs at low redshift (z < 0.3). Infrared-selected AGN fractions are ∼10–30 per cent in dwarfs, which, for reasonable duty cycles, indicates a high black hole (BH)-occupation fraction. Visual inspection of the deep HSC images indicates that the merger fraction in dwarf AGN (∼6 per cent) shows no excess compared to a control sample of non-AGN, suggesting that the AGN-triggering processes are secular in nature. Energetic arguments indicate that, in both dwarfs and massive galaxies, bolometric AGN luminosities (LAGN) are significantly greater than supernova luminosities (LSN). LAGN/LSN is, in fact, higher in dwarfs, with predictions from simulations suggesting that this ratio only increases with redshift. Together with the potentially high BH-occupation fraction, this suggests that if AGN feedback is an important driver of massive-galaxy evolution, the same is likely to be true in the dwarf regime, contrary to our classical thinking.

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The SINFONI survey of powerful radio galaxies at z ~ 2: Jet-driven AGN feedback during the Quasar Era

Astronomy and Astrophysics ◽

10.1051/0004-6361/201528040 ◽

2017 ◽

Vol 599 ◽

pp. A123 ◽

Cited By ~ 27

Author(s):

N. P. H. Nesvadba ◽

C. De Breuck ◽

M. D. Lehnert ◽

P. N. Best ◽

C. Collet

Keyword(s):

Kinetic Energy ◽

Interstellar Medium ◽

Large Scale ◽

High Redshift ◽

Radio Galaxies ◽

Energy Output ◽

Host Galaxy ◽

Powerful Radio ◽

Massive Galaxies ◽

Gas Kinematics

We present VLT/SINFONI imaging spectroscopy of the rest-frame optical emission lines of warm ionized gas in 33 powerful radio galaxies at redshifts z ≳ 2, which are excellent sites to study the interplay of rapidly accreting active galactic nuclei and the interstellar medium of the host galaxy in the very late formation stages of massive galaxies. Our targets span two orders of magnitude in radio size (2−400 kpc) and kinetic jet energy (a few 1046– almost 1048 erg s-1). All sources have complex gas kinematics with broad line widths up to ~1300 km s-1. About half have bipolar velocity fields with offsets up to 1500 km s-1 and are consistent with global back-to-back outflows. The others have complex velocity distributions, often with multiple abrupt velocity jumps far from the nucleus of the galaxy, and are not associated with a major merger in any obvious way. We present several empirical constraints that show why gas kinematics and radio jets seem to be physically related in all galaxies of the sample. The kinetic energy in the gas from large scale bulk and local outflow or turbulent motion corresponds to a few 10-3 to 10-2 of the kinetic energy output of the radio jet. In galaxies with radio jet power ≳ 1047 erg s-1, the kinetic energy in global back-to-back outflows dominates the total energy budget of the gas, suggesting that bulk motion of outflowing gas encompasses the global interstellar medium. This might be facilitated by the strong gas turbulence, as suggested by recent analytical work. We compare our findings with recent hydrodynamic simulations, and discuss the potential consequences for the subsequent evolution of massive galaxies at high redshift. Compared with recent models of metal enrichment in high-z AGN hosts, we find that the gas-phase metallicities in our galaxies are lower than in most low-z AGN, but nonetheless solar or even super-solar, suggesting that the ISM we see in these galaxies is very similar to the gas from which massive low-redshift galaxies formed most of their stars. This further highlights that we are seeing these galaxies near the end of their active formation phase.

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Large-Scale Dynamics of Molecular Clouds in the Interstellar Medium of Disk Galaxies

Theory of Accretion Disks — 2 ◽

10.1007/978-94-011-0858-4_26 ◽

1994 ◽

pp. 271-274

Author(s):

S. Linden ◽

H. Lesch ◽

F. Combes

Keyword(s):

Interstellar Medium ◽

Molecular Clouds ◽

Large Scale ◽

Disk Galaxies

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Spiral Galaxies, Elliptical Galaxies and the Large-Scale Velocity Field Within 3500 Km/s of the Local Group

Large Scale Structures of the Universe ◽

10.1007/978-94-009-2995-1_24 ◽

1988 ◽

pp. 177-180 ◽

Cited By ~ 1

Author(s):

David Burstein ◽

Roger L. Davies ◽

Alan Dressler ◽

S. M. Faber ◽

Donald Lynden-Bell ◽

...

Keyword(s):

Velocity Field ◽

Large Scale ◽

Local Group ◽

Spiral Galaxies ◽

Elliptical Galaxies

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Simulation of Mass Transport in Disk Galaxies

Symposium - International Astronomical Union ◽

10.1017/s007418090023324x ◽

1996 ◽

Vol 171 ◽

pp. 405-405 ◽

Cited By ~ 1

Author(s):

S. von Linden ◽

J. Heidt ◽

H.P. Reuter ◽

R. Wielebinski

Keyword(s):

Angular Momentum ◽

Mass Transport ◽

Large Scale ◽

Momentum Transport ◽

Disk Galaxies ◽

Angular Momentum Transport ◽

Gravitational Instabilities ◽

Gas Component

The large-scale dynamics and evolution of disk galaxies is controlled by the angular-momentum transport provided by non-axisymmetric perturbances through their gravity torques. To continuously maintain such gravitational instabilities, the presence of the gas component and its dissipative character are essential.

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