Abstract. The spiral edge-on galaxies from the "Revised Flat Galaxy Catalog" (RFGC) are identified with the Extended Source Catalog of the Two Micron All Sky Survey (2MASS). The relative number of 2MASS detected galaxies is 2996/4236 = 0.71. We consider the statistical properties of the Tully-Fisher relations for the edge-on galaxies in the B, I, J, H, and K s bands. The slope of derived TF relations increases steadily from 4.9 in the B band to 9.3 in the K one. The effect is mainly due to the internal extinction, which is different in dwarf and giant spiral galaxies seen edge-on, that leads to the tight correlation between galaxy color and luminosity. The moderate scatter of the RFGC galaxies in the "color-luminosity" diagram, 0.m 86, provides us with a "cheap" method of mass measurements of distances to galaxies on the basis of modern photometric sky surveys.

We consider a sample of thin edge-on galaxies from new a Flat Galaxy Catalogue, FGC (Karachentsev et al. 1993) covering the whole sky. The galaxies have been selected into the Catalogue by their apparent axis ratio a/b 2 7 and angular diameter a > 0.6 arcmin. Among 4455 such galaxies 893 have estimates both radial velocity and inner motion amplitude, however most part of them (542) are concentrated in the Arecibo zone. This sample is characterized by the medians: Uh = +5300 km s-' , W 5 0 = 285 km s -' and T y = Scd.To determine distances and peculiar velocities of the flat galaxies we use different modifications of the Tully-Fisher relation between linear diameter and HI linewidth taking into account also their surface brightness. A typical scatter of galaxy distance estimates by this method corresponds to dex (0.09). In a dipole approach we calculated the terms of bulk motion of the galaxies. Relative to the CMB frame the population of FGC galaxies is moving to apex 1 = 319' f lo', b = +28' f 11' with velocity 260 f 40 kms-'. Here the formal 1u errors correspond to a scattering of estimates carried out with different kinds of the T F relation (blue or red diameters, two-or three-parametric regressions).A consecutive removing of nearby galaxies by a condition of V < Vmi n leads to a rise of the mean bulk velocity and Key words: spiral galaxies -catalogues -large-scale streamings AAA subject classification: 160 IntroductionInvestigation of large-scale streamings in the Universe presents in general a complicated and branched problem.Individual distance estimates are founded either on the D, -c method for E and SO-galaxies mostly placed in the galaxy clusters or on different modifications of the Tully-Fisher (TF) relation for spiral galaxies more scattered over the sky. Peculiar motions obtained from observations are analyzed within the framework of gravitational scenario of galaxy formation in supposition that the apparent distribution of galaxies traces the distribution of graviting mass in a region of the universe under consideration. These questions are discussed widely in many papers (cf.

We used the Revised Flat Galaxy Catalog (RFGC) to create a sample of ultra-flat galaxies (UFG) covering the whole northern and southern sky apart from the Milky Way zone. It contains 817 spiral galaxies seen edge-on, selected into the UFG sample according to their apparent axial ratios (a/b) B ≥ 10.0 and (a/b) R ≥ 8.53 in the blue and red bands, respectively. Within this basic sample we fixed an exemplary sample of 441 UFG galaxies having the radial velocities of V LG < 10000 km s −1 , Galactic latitude of | b |> 10 • and the blue angular diameter of a B > 1. ′ 0. According to the Schmidt test the exemplary sample of 441 galaxies is characterized by about (80-90)% completeness, what is quite enough to study different properties of the ultra-flat galaxies. We found that more than 3/4 of UFGs have the morphological types within the narrow range of T = 7 ± 1, i.e. the thinnest stellar disks occur among the Scd, Sd, and Sdm types. The average surface brightness of UFG galaxies tends to diminish towards the flattest bulge-less galaxies. Regularly shaped disks without signs of asymmetry make up about 2/3 both among all the RFGC galaxies, and the UFG sample objects. About 60% of ultra-flat galaxies can be referred to dynamically isolated objects, while 30% of them probably belong to the scattered associations (filaments, walls), and only about 10% of them are dynamically dominating galaxies with respect to their neighbours.

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Abstract.We report the results of applying the 2MASS Tully-Fisher (TF) relations to study galaxy bulk flows. For 1141 all-sky distributed flat RFGC galaxies we construct J, H, K s TF relations and find that Kron J fe magnitudes show the smallest dispersion on the TF diagram. For the sample of 971 RFGC galaxies with V 3K < 18 000 km s −1 we find a dispersion σ TF = 0.42 m and an amplitude of bulk flow V = 199±61 km s• . Our determination of low-amplitude coherent flow is in good agreement with a set of recent data derived from EFAR, PSCz and SCI/SCII samples. The resultant two-dimensional smoothed peculiar velocity field traces well the large-scale density variations in the galaxy distributions. The regions of large positive peculiar velocities lie in the direction of the Great Attractor and Shapley concentration. A significant negative peculiar velocity is seen in the direction of Bootes and in the direction of the Local void. A small positive peculiar velocity (100-150 km s −1 ) is seen towards the Pisces-Perseus supercluster, as well as the Hercules -Coma -Corona Borealis supercluster regions.