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The polygynous invasive ant Lasius neglectus was described from Budapest, Hungary, as an unicolonial species, with no apparent colony barriers, and inferred intra-nidal mating without a nuptial flight. Here we analyze additional morphological characteristics of gynes, their physiological condition at emergence and at the time of mating and we describe the(More)
We have analysed the distribution of queens under stones at the core and at the periphery of a supercolony of Lasius neglectus that occupies 14 ha at Seva (NE Spain). Queens were not found alone, but rather within worker groups. Density at the center (mean ± s.d.: 1.38 ± 2.87 queens/stone; n = 100 stones; range 0–14) was not different from density at the(More)
We present images, integrated photometry, surface-brightness and color profiles for a total of 1034 nearby galaxies recently observed by the Galaxy Evolution Explorer (GALEX) satellite in its far-ultraviolet (FUV; λeff=1516 Å) and nearultraviolet (NUV; λeff=2267 Å) bands. Our catalog of objects is derived primarily from the GALEX Nearby Galaxies Survey(More)
We present ultraviolet (UV) photometry of M31 globular clusters (GCs) found in 23 Galaxy Evolution Explorer (GALEX) images covering the entirety of M31. We detect 485 and 273 GCs (and GC candidates) in the near-ultraviolet (NUV; λeff = 2267 Å, ∆λ = 732 Å) and far-ultraviolet (FUV; λeff = 1516 Å, ∆λ = 268 Å), respectively. Our UV catalog has been(More)
We present high-precision V , B − V color-magnitude diagrams (CMDs) for the classic second parameter globular clusters M3 and M13 from wide-field deep CCD photometry. The data for the two clusters were obtained during the same photometric nights with the same instrument, allowing us to determine accurate relative ages. Based on a differential comparison of(More)
Context. In recent years, increasing evidence for chemical complexity and multiple stellar populations in massive globular clusters (GCs) has emerged, including extreme horizontal branches (EHBs) and UV excess. Aims. Our goal is to improve our understanding of UV excess in compact stellar systems, covering the regime of both ultra-compact dwarf galaxies(More)
We present Galaxy Evolution Explorer (GALEX) far-UV and near-UV mosaic observations covering the entirety of M31 and M33. For both targets, we measure the decline of surface brightness (in FUV and NUV) and changes in FUV–NUV color as a function of galactocentric radius. These UV radial profiles are compared to the distribution of ionized gas traced by Hα(More)
We present deep wide field V I CCD photometry of the Sextans dwarf spheroidal galaxy (dSph) in the Local Group, covering a field of 42 × 28 located at the center of the galaxy (supplemented by short B photometry). The limiting magnitudes with 50 % completeness are V = 24.4 mag and I = 23.6 mag. Color-magnitude diagrams of the Sextans dSph show welldefined(More)
The rst large-format CCD color-magnitude diagram (CMD) in the B and V passbands is presented for the Galactic globular cluster M53 (NGC 5024). The observations consist of 40 pairs of B and V CCD frames with FWHM <1 00 .2. These frames were used to produce color-magnitude data for more than 20000 stars from the tip of the red giant-branch (RGB) to about two(More)
We present new measurements of the metallicity of 131 RR Lyrae stars in the globular cluster ω Centauri, using the hk index of the Caby photometric system. The hk method has distinct advantages over ∆S and other techniques in determining the metallicity of RR Lyrae stars, and has allowed us to obtain the most complete and homogeneous metallicity data to(More)