The morphological types of galaxies in the Local Supercluster

2014 ◽  
Vol 11 (S308) ◽  
pp. 464-466
Author(s):  
K. Bajan ◽  
P. Flin ◽  
W. Godłowski
Keyword(s):  
Axial Ratio ◽  
Morphological Type ◽  
Radial Velocities ◽  
Local Supercluster

AbstractOn the basis of the Hyper – Leda Catalogue HyperLeda 8293 galaxies with heliocentric radial velocities below 2500 km s-1 were selected; 4570 had known morphological types (4366 had calculated b/a ratio). We checked the frequency of the distribution of various types in the LSC, finding spirals and irregulars most numerous, in accordance with expectations. The axial ratio of galaxy diameters of various types was studied, and the dependence of this parameter on the morphological type was noted.

scholarly journals Some Properties of Galaxy Structures

2011 ◽  
Vol 20 (2) ◽  
Author(s):  
Piotr Flin ◽  
Monika Biernacka ◽  
Włodzimierz Godłowski ◽  
Elena Panko ◽  
Paulina Piwowarska
Keyword(s):  
Spatial Orientation ◽  
Velocity Dispersion ◽  
Statistical Tests ◽  
Scale Up ◽  
Morphological Type ◽  
Strongly Correlated ◽  
Galaxy Groups ◽  
Abell Clusters ◽  
Local Supercluster ◽  
The Galaxy

AbstractWe analysed some properties of galaxies structures based on the PF catalog of galaxy structures (Panko & Flin 2006) and the Tully NBG catalog (Tully 1988). At first, we analyzed the orientation of galaxies in the 247 optically selected rich Abell clusters, having at least 100 members. The distribution of the position angles of galaxies as well as of two angles describing spatial orientation of the galaxy planes were tested for isotropy, applying three statistical tests. We found the relation between the anisotropy and the cluster richness. The relation between the galaxy alignment and the Bautz-Morgan morphological type of the parent cluster is not present. A statistically marginal relation between the velocity dispersion and cluster richness is observed. We also analyzed ellipticities for 6188 low redshift (z < 0.18) poor and rich galaxy structures which have been examined along with their evolution. Finally, we analyzed the Binggeli effect and found that the orientation of galaxy groups in the Local Supercluster (LSC), is strongly correlated with the distribution of neighbouring groups in the scale up to about 20 Mpc. Analysis of galaxy structures from the PF catalog shows quite different situation - the efect is observed only for more elongated structures (e ≤ 0.3). The effect is present in a distance range of about 60 h

scholarly journals The Orientation of Galaxies in Superclusters

1988 ◽  
Vol 130 ◽  
pp. 239-241
Author(s):  
Piotr Flin
Keyword(s):  
Positive Result ◽  
Spatial Orientation ◽  
Axial Ratio ◽  
Major Axis ◽  
Position Angle ◽  
Main Plane ◽  
Local Supercluster ◽  
The Galaxy ◽  
Spatial Geometry

The alignment of galaxies with the main plane of supercluster can contribute to recovering information on the structure origin. The positive result of the preliminary search for galaxy alignment in the Local Supercluster /Flin and Godlowski 1986, hereafter FG/ have stimulated further studies. Following Jaaniste and Saar /1977/, the both parameters, the position angle of the galaxy major axis p and the axial ratio b/a of the galaxy image, were used for the better determination of the actual spatial orientation of the galaxy disc. This approach also permit to consider “face-on” objects, whose discounting leads to obvious incompleteness of the analysed data. Each galaxy has two possible orientations and both were taken into account during calculations. The analysis is perfomed by transforming position angle p and coordinates α, δ of galaxies expressed in the equatorial coordinates into coordinate system connected with each parent supercluster separately, which gives parameters P, l and b respectively. The main supercluster plane should be determined, which resticts the present study to the three superclusters with a known spatial geometry, i.e. LSC /Tully 1982/, Perseus and Coma/A1367 /Chincarini et al. 1983/.

On the Inhomogeneity of Chemical Composition over the Surface of 21 Per

1976 ◽  
Vol 32 ◽  
pp. 343-349
Author(s):  
Yu.V. Glagolevsky ◽  
K.I. Kozlova ◽  
V.S. Lebedev ◽  
N.S. Polosukhina
Keyword(s):  
Chemical Composition ◽  
Spectral Line ◽  
Variable Star ◽  
Radial Velocities ◽  
Crimean Astrophysical Observatory ◽  
Line Intensities ◽  
Magnetic Variable

SummaryThe magnetic variable star 21 Per has been studied from 4 and 8 Å/mm spectra obtained with the 2.6 - meter reflector of the Crimean Astrophysical Observatory. Spectral line intensities (Wλ) and radial velocities (Vr) have been measured.

Polygonal profiles of ferritin molecules

1983 ◽  
Vol 41 ◽  
pp. 600-601
Author(s):  
William H. Massover
Keyword(s):  
Axial Ratio ◽  
X Ray Diffraction ◽  
Rhombic Dodecahedron ◽  
Apparent Contradiction ◽  
Iron Storage ◽  
X Ray ◽  
Hexagonal Shape ◽  
Axes Of Symmetry ◽  
Apparent Conflict ◽  
Iron Storage Protein

The molecular structure of the iron-storage protein, ferritin, is becoming known in ever finer detail. The 24 apoferritin subunits (MW ca. 20,000) have a 2:1 axial ratio and are polymerized with 4:3:2 symmetry to form an outer shell surrounding a variable amount of microcrystalline iron, Recent x-ray diffraction results indicate that the projected outline of the native molecule has a quasi-hexagonal shape when viewed down the 3-fold axes of symmetry, and a quasi-square shape when looking down the 4-fold axes. To date, no electron microscope study has reported observing anything other than circular profiles, which would indicate that ferritin is strictly spherical. The apparent conflict between the "hollow sphere" of electron microscopy (E.M.) and the "truncated rhombic dodecahedron" of x-ray diffraction could reflect the poorer effective resolution of E.M. coming from radiation damage, staining, drying, etc. The present study investigates the detailed shape of individual ferritin molecules in order to search for the predicted aspherical profiles and to interpret the nature of this apparent contradiction.

The microtubule associated protein (MAP) tau forms a new class of triple-stranded left-hand helical fibrous protein polymer

1992 ◽  
Vol 50 (1) ◽  
pp. 540-541
Author(s):  
G. C. Ruben ◽  
K. Iqbal ◽  
I. Grundke-Iqbal ◽  
H. Wisniewski ◽  
T. L. Ciardelli ◽  
...  
Keyword(s):  
Axial Ratio ◽  
Normal Structure ◽  
Paired Helical Filaments ◽  
Left Hand ◽  
New Class ◽  
Protein Polymer ◽  
Fibrous Protein ◽  
Protein Map ◽  
Neurotransmitter Transport ◽  
Alzheimer Neurofibrillary Tangles

In neurons, the microtubule associated protein, tau, is found in the axons. Tau stabilizes the microtubules required for neurotransmitter transport to the axonal terminal. Since tau has been found in both Alzheimer neurofibrillary tangles (NFT) and in paired helical filaments (PHF), the study of tau's normal structure had to preceed TEM studies of NFT and PHF. The structure of tau was first studied by ultracentrifugation. This work suggested that it was a rod shaped molecule with an axial ratio of 20:1. More recently, paraciystals of phosphorylated and nonphosphoiylated tau have been reported. Phosphorylated tau was 90-95 nm in length and 3-6 nm in diameter where as nonphosphorylated tau was 69-75 nm in length. A shorter length of 30 nm was reported for undamaged tau indicating that it is an extremely flexible molecule. Tau was also studied in relation to microtubules, and its length was found to be 56.1±14.1 nm.

Radial Velocities, Binarity, and Kinematic Membership in the Open Cluster NGC 2516

2000 ◽  
Vol 119 (5) ◽  
pp. 2296-2302 ◽  
Author(s):  
Jorge Federico González ◽  
Emilio Lapasset
Keyword(s):  
Open Cluster ◽  
Radial Velocities

scholarly journals Galaxy Formation: Some Comparisons between Theory and Observation

1983 ◽  
Vol 100 ◽  
pp. 391-399 ◽  
Author(s):  
S. Michael Fall
Keyword(s):  
Galaxy Formation ◽  
Total Mass ◽  
Virial Theorem ◽  
Velocity Dispersion ◽  
Rotation Velocity ◽  
Morphological Type ◽  
Fundamental Parameter ◽  
Mass Ratio ◽  
First Approximation ◽  
Type Form

Before theoretical ideas in this subject can be compared with observational data, it is necessary to consider the properties of galaxies that are likely to be relics of their formation. Most astronomers would agree that the list of important parameters should be headed by the total mass M, energy E and angular momentum J. Next on the list should probably be the relative contributions to these quantities from the disc and bulge components of galaxies and denoted D/B for the mass ratio. They can be estimated from the median (i.e. half-mass) radius R, velocity dispersion σ and rotation velocity v of each component, either through the virial theorem or through the luminosity L and an assumed value of M/L. As a first approximation, it is reasonable to suppose that galaxies of a given disc-to-bulge ratio or morphological type form a sequence with mass as the fundamental parameter. The comparison of theory with data is further simplified by considering the extreme cases of ellipticals, with D/B << 1, and late-type spirals, with D/B >> 1. The approach outlined below is to explore the consequences of relaxing in succession the constraints that E, J and M be conserved during the collapse of proto-galaxies. In this article I concentrate on theories that are based on some form of hierarchical clustering because the pancake and related theories are not yet refined enough for a detailed confrontation with observations.

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