相关论文: The Absolute Magnitudes of Red Horizontal Branch S…

The Space Telescope Imaging Spectrograph has measured the absolute flux for Vega from 0.17-1.01 microns on the HST White Dwarf flux scale. These data are saturated by up to a factor of 80 overexposure but retain linearity to a precision of…

We characterize the absolute magnitudes and colors of RR Lyrae stars in the globular cluster M5 in the ugriz filter system of the Dark Energy Camera (DECam). We provide empirical Period-Luminosity (P-L) relationships in all 5 bands based on…

The tip of the red giant branch (TRGB) provides a key standard candle for extragalactic distance measurements and for refining the Hubble constant. We test its robustness by quantifying how metallicity, $\alpha$-element enhancement, age,…

We present an abundance analysis of seven super-star clusters in the disk of M83. The near-infrared spectra of these clusters are dominated by Red Supergiants, and the spectral similarity in the J-band of such stars at uniform metallicity…

Understanding the age and metallicity dependence of the absolute magnitude and colour of red clump (RC) stars is crucial for validating the accuracy of stellar evolution models and enhancing their reliability as a standard candle. However,…

We present a detailed abundance analysis and atmospheric parameters of 76 stars from a survey to identify field Galactic red horizontal-branch (RHB) stars. High-resolution echelle spectra (R\simeq60,000, S/N>=100) were obtained with 2.7 m…

Hipparcos parallax data for 40 contact binary stars of the W UMa-type (with errors in M_V < 0.5) are used to derive a new, (B-V)-based absolute-magnitude calibration of the form M_V = M_V(logP,B-V). The calibration covers the ranges 0.26 <…

The absolute visual magnitude as function of the observed colour (B-V), also named Hertzsprung-Russell diagram can be described through five equations; that in presence of calibrated stars means eight constants. The developed framework…

AGB phases mark the end of the evolution for Low- and Intermediate-Mass Stars. Our understanding of the mechanisms through which they eject the envelope and our assessment of their contribution to the chemical evolution of Galaxies are…

We examine the reliability of the tip of the red giant branch (TRGB) as a distance indicator for stellar populations with different star formation histories (SFHs) when photometric errors and completeness corrections at the TRGB are small.…

We use synthetic photometry from Gaia DR3 BP and RP spectra for a large selected sample of stars in the Large Magellanic Cloud (LMC) and Small Magellanic Cloud (SMC) to derive the magnitude of the Red Giant Branch (RGB) tip for these two…

We compare Stetson's photometric standards with measurements listed in a standard star catalog constructed using repeated SDSS imaging observations. The SDSS catalog includes over 700,000 candidate standard stars from the equatorial stripe…

The tip of the red giant branch (TRGB) allows for the measurement of precise and accurate distances to nearby galaxies, based on the brightest ascent of low-mass red giant branch stars before they undergo the helium flash. With the advent…

The Tip of the Red Giant Branch (TRGB)-based distance method in the I band is one of the most efficient and precise techniques for measuring distances to nearby galaxies (D <= 15 Mpc). The TRGB in the near infrared (NIR) is 1 to 2…

We present a new luminosity-colour relation based on trigonometric parallaxes for thin disc main-sequence stars in SDSS photometry. We matched stars from the newly reduced Hipparcos catalogue with the ones taken from 2MASS All-Sky Catalogue…

In the fourth paper of this series, we present the metallicity-dependent Sloan Digital Sky Survey (SDSS) stellar color loci of red giant stars, using a spectroscopic sample of red giants in the SDSS Stripe 82 region. The stars span a range…

[...] The aim of this paper is to study the precision and theoretical biases in the age determinations of halo stars adopting both asteroseismic and classic observational constraints. [...] We adopt the well-tested SCEPtER pipeline,…

The tip of the red giant (TRGB) is a standardizable candle and is identifiable as the discontinuity at the bright extreme of the red giant branch (RGB) stars in color-magnitude diagram (CMD) space. The TRGB-based distance method has been…

We present accurate integrated-light photometry in Johnson/Cousins V, R, and I for a sample of 28 globular clusters in the Magellanic Clouds. The majority of the clusters in our sample have reliable age and metallicity estimates available…

We present new high-quality near-infrared photometry of 10 Galactic Globular Clusters spanning a wide metallicity range (-2.12<[Fe/H]<-0.49): five clusters belong to the Halo (namely, NGC288, NGC362, NGC6752, M15 and M30) and five (namely,…