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Dark energy domination in the Virgocentric flow

Context. The standard ΛCDM cosmological model implies that all celestial bodies are embedded in a perfectly uniform dark energy background, represented by Einstein's cosmological constant, and experience its repulsive antigravity action.Aims. Can dark energy have strong dynamical effects on small cosmic scales as well as globally? Continuing our efforts to clarify this question...

Dark energy domination in the Virgocentric flow

Context. The standard ΛCDM cosmological model implies that all celestial bodies are embedded in a perfectly uniform dark energy background, represented by Einstein's cosmological constant, and experience its repulsive antigravity action.Aims. Can dark energy have strong dynamical effects on small cosmic scales as well as globally? Continuing our efforts to clarify this question...

Hα imaging of the local volume galaxies - I. The NGC 6946 galaxy group

We present new Hα imaging of all known dwarf irregular companions to NGC 6946: UGC 11583, KK 251, KK 252, KKR 55, KKR 56, Cepheus 1, KKR 59, and KKR 60. The galaxies span a range of blue absolute magnitudes of [ -13.6, -17.6] , relative gas content of [0.1, 2.5] , current star formation activity of yr-1, and timescale to exhaust the current gas supply of [6, 86] Gyr.

Gas distribution, kinematics and star formation in faint dwarf galaxies

We compare the gas distribution, kinematics and the current star formation in a sample of 10 very faint (−13.37 < MB < −9.55) dwarf galaxies. For five of these galaxies we present fresh, high-sensitivity, Giant Metrewave Radio Telescope H i 21-cm observations. We find that the large-scale H i distribution in the galaxies is typically irregular and clumpy, with the peak gas...

A supplementary list of southern nearby dwarf galaxy candidates

To improve the census of the Local Volume galaxies, we carried out a systematic search for nearby dwarf galaxies in a declination range of based on the ESO/SERC film copies. As a result, we present a list of 81 nearby dwarf galaxy candidates of low surface brightness which have angular diameters . Half of the objects have been found for the first time. This sample may be...

Photometric distances to six bright resolved galaxies

We present photometry of the brightest stars in six nearby spiral and irregular galaxies with corrected radial velocities from 340 to 460 km s-1. Three of them are resolved into stars for the first time. Based on luminosity of the brightest blue stars we estimate the following distances to the galaxies: 5.0 Mpc for NGC 784, 9.2 Mpc for NGC 2683, 8.9 Mpc for NGC 2903, 4.1 Mpc for...

CCD imaging of twenty nearby isolated irregular galaxies

We present B, V and I CCD stellar photometry for a sample of 20 field irregular dwarf galaxies. Their corrected radial velocity is 500 km s-1. Most of them have been resolved into stars for the first time. Based on photometry of their brightest blue stars we have derived the following distances: 5.9 Mpc (UGC 685), 5.4 Mpc (UGC 1281), 7.2 Mpc (UGC 3303), 7.0 Mpc (UGC 3476), 7.3...

Imaging and photometry of nearby dwarf galaxies - II. Southern dwarfs

We carried out CCD photometry in the Johnson-Cousins B and R bands of 23 dwarf galaxies: SDIG, ESO 410-17, KK11, ESO 245-05, KKs3, KK27, KK38, KK40, IC 4662, KK244, KK246, KK247, KK248, KK249, KK253, KK255, KK256, KK257, KK258, KK259, UGCA 438, ESO 347-17, and UGCA 442. Both isolated galaxies and members of the Sculptor group and the NGC 1313 group were observed. The galaxy...

CCD photometry and distances of six resolved irregular galaxies in Canes Venatici

The results of detailed imaging of six nearby irregular galaxies with radial velocities  km/s are presented. Except for one all the galaxies have been resolved into stars for the first time. Based on photometry of the brightest blue stars we derived the following distances to the galaxies: 3.6 Mpc for NGC 4163, 3.5 Mpc for NGC 4190, 8.6 Mpc for UGC 7298, 4.8 Mpc for UGC 7577, 3.7...

CCD photometry and distances of six resolved irregular galaxies in Canes Venatici

The results of detailed imaging of six nearby irregular galaxies with radial velocities  km/s are presented. Except for one all the galaxies have been resolved into stars for the first time. Based on photometry of the brightest blue stars we derived the following distances to the galaxies: 3.6 Mpc for NGC 4163, 3.5 Mpc for NGC 4190, 8.6 Mpc for UGC 7298, 4.8 Mpc for UGC 7577, 3.7...

CCD photometry and distances of six resolved irregular galaxies in Canes Venatici

The results of detailed imaging of six nearby irregular galaxies with radial velocities  km/s are presented. Except for one all the galaxies have been resolved into stars for the first time. Based on photometry of the brightest blue stars we derived the following distances to the galaxies: 3.6 Mpc for NGC 4163, 3.5 Mpc for NGC 4190, 8.6 Mpc for UGC 7298, 4.8 Mpc for UGC 7577, 3.7...

Cam A: a new dwarf low-surface-brightness galaxy on the Local Group outskirts?

We present a deep I-band image of the nearby dwarf irregular galaxy Cam A obtained with the Nordic Optical Telescope with 0.6-arcsec seeing (FWHM). The distance to Cam A, DMW=1.9 Mpc, is estimated from the tip of the red giant branch seen at I=22.8±0.2 mag. The youngest stellar population of the galaxy seems to be of age about 100 Myr. Relying on its barycentric distance, DLG=1.6...

A list of nearby dwarf galaxies towards the Local Void in Hercules-Aquila

Based on film copies of the POSS-II we inspected a wide area of □° in the direction of the nearest cosmic void: {RA = 18h 38m, , 1500 km s-1}. As a result we present a list of 78 nearby dwarf galaxy candidates which have angular diameters and a mean surface brightness , mag/□″. Of them 22 are in the direction of the Local Void region. To measure their redshifts, a HI survey of...

HI observations of nearby galaxies - I. The first list of the Karachentsev catalog

We present HI observations of the galaxies in the first list of the Karachentsev catalog of previously unknown nearby dwarf galaxies (Karachentseva & Karachentsev 1998). This survey covers all known nearby galaxy groups within the Local Volume (i.e. within 10 Mpc) and their environment, that is about 25% of the total sky. A total of 257 galaxies have been observed with a...

Dwarf galaxy candidates found on the SERC EJ sky survey

We inspected a sky region with declination range of [ 0°, -18°] based on the SERC EJ plate copies. As a result a list of 50 nearby dwarf galaxy candidates with angular diameters is presented. Most of the galaxies have low and very low surface brightness. More than 60% of the objects are detected for the first time.

Dwarf galaxy candidates found on the SERC EJ sky survey

We inspected a sky region with declination range of [ 0°, -18°] based on the SERC EJ plate copies. As a result a list of 50 nearby dwarf galaxy candidates with angular diameters is presented. Most of the galaxies have low and very low surface brightness. More than 60% of the objects are detected for the first time.

Photometric distances to NGC 628 and its four companions

Based on photometry of the brightest blue stars we derived distance moduli for NGC 628 and its dwarf irregular companions: DDO 13, UGC 1171, UGC 1104, and K 10. The mean modulus of the group is estimated to be 29.46 mag with a formal (internal) error of 0.11. The total mass to luminosity ratio of 40 seems sufficient for NGC 628 to keep its companions in bound orbits.

Photometric properties of the Local Volume dwarf galaxies*

We present surface photometry and metallicity measurements for 104 nearby dwarf galaxies imaged with the Advanced Camera for Surveys and Wide Field and Planetary Camera 2 aboard the Hubble Space Telescope. In addition, we carried out photometry for 26 galaxies of the sample and for Sextans B on images of the Sloan Digital Sky Survey. Our sample comprises dwarf spheroidal...

Global anisotropy in galaxy orientations

We suggest a new method for investigating the distribution of the orientations of galaxies. This method is used to process data from the UGC and ESO catalogues, and from the catalogue of flat edge-on galaxies compiled by the authors (FGC). A statistically significant anisotropy is detected, and possible reasons for this are analysed. The orientation distribution is described by a...

Distances to nearby galaxies in Sculptor

We present an analysis of Hubble Space Telescope/WFPC2 images of nine nearby galaxies in Sculptor. We derive their distances from the luminosity of the tip of the red giant branch stars with a typical accuracy of ∼ 12%. Their distances are 4.21 Mpc (Sc 22), 4.92 Mpc (DDO 226), 3.94 Mpc (NGC 253), 3.40 Mpc (KDG 2), 3.34 Mpc (DDO 6), 3.42 Mpc (ESO 540-030), 4.43 Mpc (ESO 245–05), 4...