相关论文: The effect of diffusion on the Red Giant luminosit…

In this paper we present the V and I luminosity functions and color-magnitude diagrams derived from wide-field (23 arcmin by 23 arcmin) BVI photometry of the intermediate metallicity ([Fe/H]=-1.3) Galactic globular cluster M12. Using…

NGC288 is a globular cluster with a well-developed blue horizontal branch covering the u-jump that indicates the onset of diffusion. It is therefore well suited to study the effects of diffusion in blue horizontal branch (HB) stars. We…

We present photometry for all bright red giant branch (RGB), horizontal branch (HB), and asymptotic giant branch (AGB) stars within 10' of the center of M13. We find support for the idea that the population of HB stars redder than the…

Diffusion of elements in the atmosphere and envelope of a star can drastically alter its surface composition, leading to extreme chemical peculiarities. We consider the case of hot subdwarfs, where surface helium abundances range from…

The brightness of the tip of the Red Giant Branch is a useful reference quantity for several fields of astrophysics. An accurate theoretical prediction is needed for such purposes. Aims. We intend to provide a solid theoretical prediction…

We investigate the effects of dust on Large Magellanic Cloud (LMC) HII region spectral energy distributions using arcminute-resolution far-ultraviolet (FUV), H-alpha, far-infrared (FIR), and radio images. Widely-used indicators of the…

An excess of sight-lines close to Lyman-break galaxies (LBGs) with little or no absorption in QSO absorption spectra has been reported and has been interpreted as the effect of galactic winds on the Intergalactic Medium. We use here…

The existence of star-to-star light-element abundance variations (multiple populations, MPs) in massive Galactic and extragalactic star clusters older than about 2 Gyr is by now well established. Photometry of red giant branch (RGB) stars…

The linear growth factor of density perturbations is believed to be a powerful observable of future redshift surveys to probe physical properties of dark energy and to distinguish among gravity theories. We investigate systematic effects on…

We explore the feasibility and limitations of using the 1.6um bump as a photometric redshift indicator and selection technique and use it to study the rest-frame H-band galaxy luminosity and stellar mass functions at redshift z~2. We use…

Some beyond $\Lambda$CDM cosmological models have dark-sector energy densities that suffer phase transitions. Fluctuations entering the horizon during such a transition can receive enhancements that ultimately show up as a distinctive bump…

The double red clump (RC) observed in the Milky Way bulge is widely interpreted as evidence for an X-shaped structure. We have recently suggested, however, an alternative interpretation based on the multiple population phenomenon, where the…

The aim of this paper is to check if the models with realistic inhomogeneous matter distribution and without cosmological constant can explain the dimming of the supernovae in such a way that it can be interpreted as an acceleration of the…

I describe the principle of using the 1.6um H- spectral feature as a photometric redshift indicator and demonstrate that the technique holds promise by successfully recovering the redshifts of a small sample of z=0-1 galaxies using only…

I review the characteristics of high redshift galaxies, with particular attention to the effects of dust obscuration on the observed light. Galaxies at redshift z~1 and at z>2 are discussed separately, as the accessible information for each…

We derive the optical luminosity, colors, and ratios of the blue and red helium burning (HeB) stellar populations from archival Hubble Space Telescope observations of nineteen starburst dwarf galaxies and compare them with theoretical…

In a Globular Cluster (GC), the mass loss during the red-giant branch (RGB) phase and the helium content are fundamental ingredients to constrain the horizontal branch (HB) morphology. While many papers have been dedicated to the helium…

We compute full evolutionary sequences of red giant branch stars close to the luminosity bump by including state of the art composition transport prescriptions for the thermohaline mixing regimes. In particular we adopt a self-consistent…

Mapping lithium evolution for evolved stars will provide restrictions and constraints on the fundamental stellar interior physical processes, which further shed light on our understanding of the theory of stellar structure and evolution.…

We show that macroscopic dark matter (DM) impacts on the degenerate helium cores of red-giant branch (RGB) stars can ignite helium fusion via DM-baryon elastic scattering. The onset of helium burning leads to a characteristic drop in…