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arXiv · 1010.5585

Winding sense of galaxies around the Local Supercluster

Abstract

We present an analysis of the winding sense (S and Z-shaped) of 1\,621 field galaxies that have radial velocity between 3\,000 km s$^{-1}$ to 5\,000 km s$^{-1}$. The preferred alignments of S- and Z-shaped galaxies are studied using chi-square, auto-correlation and the Fourier tests. We classified total galaxies into 32 subsamples and noticed a good agreement between the position angle (PA) distribution of S- and Z-shaped galaxies. The homogeneous distribution of the S- and Z-shaped galaxies is noticed for the late-type spirals (Sc, Scd, Sd and Sm) than that of the early-types (Sa, Sab, Sb and Sbc). A significant dominance of S-mode galaxies is noticed in the barred spirals. A random alignment is noticed in the PA-distribution of Z- and S-mode spirals. In addition, homogeneous distribution of the S- and Z-shaped galaxies is found to be invariant under the global expansion. The PA-distribution of the total S-mode galaxies is found to be random, whereas preferred alignment is noticed for the total Z-mode galaxies. It is found that the galactic planes of Z-mode galaxies tend to lie in the equatorial plane.

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B. Aryal. 2010-10-27. Winding sense of galaxies around the Local Supercluster. https://doi.org/10.1088/1674-4527/11/3/004

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