Detailed surface photometry for 79 (mostly dwarf) galaxies in the NGC5044 Group area is analysed, revealing the existence of different morphologies among objects originally classified as early-type dwarfs. Particularly, a significant fraction of bright dwarf “ellipticals” show a distinct bulge+disc structure; we thus re-classify these objects as dwarf lenticulars (dS0). Our finding points at a ...

Aims. The ESO SN Ia Progenitor Survey (SPY) aims at finding merging double degenerate binaries as candidates for supernova type Ia (SN Ia) explosions. A white dwarf merger has also been suggested to explain the formation of rare types of stars like R CrB, extreme helium or He sdO stars. Here we present the hot subdwarf B binary GD 687, which will merge in less than a Hubble time. Methods. The o...

The distance to the Fornax dwarf galaxy using red clump stars, and the discrepancy between red clump and tip of the red giant branch distances ABSTRACT I determine a distance to the Fornax dwarf galaxy using stars in the red clump and at the tip of the red giant branch. They are in very good agreement, with µ 0 = 20.66 mag. Comparing the magnitudes of the tip of the red giant branch and of the ...

We compare some of the properties of rapid oscillations in cataclysmic variables and X-Ray binaries. In addition to the earlier recognition that both types possess the same correlation between high and low frequency quasi-periodic oscillations, we have now found that the dwarf nova VW Hyi in its late stages of outburst shows the 1:2:3 oscillation harmonics that are seen in some neutron star and...

The interpretation of pulsation data for Sun-like stars is currently facing challenges quite similar to those faced by white dwarf modelers ten years ago. The observational requirements for uninterrupted long-term monitoring are beginning to be satisfied by successful multi-site campaigns and dedicated satellite missions. But exploration of the most important physical parameters in theoretical ...

Reproductive parasitism among males is prevalent in fishes. Typically, small ripe males parasitize the reproductive effort of large bourgeois males by using various behavioural tactics. We examined the size-dependent advantages of parasitic behavioural tactics in a shell-brooding cichlid fish of Lake Tanganyika with three male types (large bourgeois males and medium–dwarf parasitic males). The ...

We have obtained 1.0—2.5μm spectra at R∼600 of 14 disk dwarfs with spectral types M6 to L7. For four of the dwarfs we have also obtained infrared spectra at R∼3000 in several narrow intervals. In addition, we present new L′ photometry for four of the dwarfs in the sample, which allows improved determinations of their bolometric luminosities. While obtaining the photometry we resolved the L-dwar...

The simplicity and extreme ages of globular clusters and dwarf galaxies imply that these systems may be useful windows to the earliest era of galaxy formation. Recent discoveries of local dwarfs have, in some ways, begun to blur the distinctions between the two types of systems. However, it remains clear that the two types of systems arose from fundamentally different conditions in the early Un...