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Related papers: Cepheids as tracers of the metallicity gradient ac…

200 papers

We gathered more than 1130 high-resolution optical spectra for more than 250 Galactic classical Cepheids. The spectra were collected with different optical spectrographs: UVES at VLT, HARPS at 3.6m, FEROS at 2.2m MPG/ESO, and STELLA. To…

We present new empirical and theoretical calibrations of two photometric metallicity indices based on Walraven photometry. The empirical calibration relies on a sample of 48 Cepheids for which iron abundances based on high resolution…

We present new accurate abundances for five neutron-capture (Y, La, Ce, Nd, Eu) elements in 73 classical Cepheids located across the Galactic thin disk. Individual abundances are based on high spectral resolution (R ~ 38,000) and high…

The Cepheid period-luminosity (PL) relation is unquestionably one of the most powerful tools at our disposal for determining the extragalactic distance scale. While significant progress has been made in the past few years towards its…

We present new homogeneous measurements of Na, Al and three alpha-elements (Mg, Si, Ca) for 75 Galactic Cepheids. The abundances are based on high spectral resolution (R ~ 38,000) and high signal-to-noise ratio (S/N ~ 50-300) spectra…

This paper reports on the spectroscopic investigation of 238 Cepheids in the northern sky. Of these stars, about 150 are new to the study of the galactic abundance gradient. These new Cepheids bring the total number of Cepheids involved in…

Astrophysics of Galaxies · Physics 2015-05-30 R. Earle Luck , David L. Lambert

Classical Cepheids (CCs) have long been considered excellent tracers of the chemical evolution of the Milky Way's young disk. We present a homogeneous, NLTE spectroscopic analysis of 401 Galactic CCs, based on 1,351 high-resolution optical…

In this paper we have compiled two new open cluster catalogues. In the first one, there are 119 objects with ages, distances and metallicities available, while in the second one, 144 objects have both absolute proper motion and radial…

Astrophysics · Physics 2009-11-07 L. Chen , J. L. Hou , J. J. Wang

We have measured the elemental abundances of 68 Galactic and Magellanic Cepheids from FEROS and UVES high-resolution and high signal-to-noise spectra in order to establish the influence of the chemical composition on the properties of these…

Astrophysics · Physics 2010-12-09 M. Mottini , M. Romaniello , F. Primas , G. Bono , M. A. T. Groenewegen , P. Francois

We present the study of the metallicity dependence of the Fourier amplitude ratios R_21 and R_31 for the light curves of short-period Galactic classical Cepheids in B, V, R_C and I_C bands. Based on the available photometric and…

Solar and Stellar Astrophysics · Physics 2013-08-01 P. Klagyivik , L. Szabados , A. Szing , S. Leccia , N. Mowlavi

Open clusters offer a unique possibility to study the time evolution of the radial metallicity gradients of several elements in our Galaxy, because they span large intervals in age and Galactocentric distance, and both quantities can be…

Astrophysics · Physics 2009-11-13 Laura Magrini , Paola Sestito , Sofia Randich , Daniele Galli

We present metallicities, [Fe/H], and elemental abundance ratios, [X/Fe], for a sample of 24 Cepheids in the outer Galactic disk. The sample have Galactocentric distances covering 12 < R_GC (kpc) < 17.2 making them the most distant Galactic…

Astrophysics · Physics 2008-11-26 David Yong , Bruce W. Carney , Luisa de Almeida , Brian L. Pohl

Physical and phenomenological properties (radius, luminosity, shape of the light curve, etc.) of Cepheids strongly depend on the pulsation period, with the exception of the pulsation amplitude. A possible factor causing a wide range of…

Solar and Stellar Astrophysics · Physics 2012-01-13 László Szabados , Péter Klagyivik

We provided accurate estimates of distances, radii and iron abundances for four metal-rich Cepheids, namely V340 Ara, UZ Sct, AV Sgr and VY Sgr. The main aim of this investigation is to constrain their pulsation properties and their…

Solar and Stellar Astrophysics · Physics 2015-05-18 S. Pedicelli , B. Lemasle , M. Groenewegen , M. Romaniello , G. Bono , C. D. Laney , P. Francois , R. Buonanno , F. Caputo , J. Lub , J. W. Pel , F. Primas , J. Pritchard

The problem of the chemical composition gradient in the galactic disk is studied based on a sample of metallicity estimates of open star clusters, using Gaia DR2-improved distance estimates. A clearly non-monotonic variation was observed in…

Solar and Stellar Astrophysics · Physics 2020-05-06 A. V. Loktin , M. E. Popova

A sample of 37 Galactic, 10 LMC and 6 SMC cepheids is compiled for which individual metallicity estimates exist and BVIK photometry in almost all cases. The Galactic cepheids all have an individual distance estimate available. For the MC…

Astrophysics · Physics 2009-11-10 M. A. T. Groenewegen , M. Romaniello , F. Primas , M. Mottini

Open clusters are known as excellent tools for various topics in Galactic research. For example, they allow accurately tracing the chemical structure of the Galactic disc. However, the metallicity is known only for a rather low percentage…

Solar and Stellar Astrophysics · Physics 2016-01-13 M. Netopil , E. Paunzen , U. Heiter , C. Soubiran

This paper reports on the spectroscopic investigation of 101 Cepheids in the Carina region. These Cepheids extend previous samples by about 35% in number and increase the amount of the galactic disk coverage especially in the direction of l…

Astrophysics of Galaxies · Physics 2015-05-28 R. E. Luck , S. M. Andrievsky , V. V. Kovtyukh , W. Gieren , D. Graczyk

The structure, kinematics, and chemical composition of the far side of the Milky Way disk, beyond the bulge, are still to be revealed. Classical Cepheids (CCs) are young and luminous standard candles. We aim to use a well-characterized…

Radial metallicity gradients are observed in the disks of the Milky Way and in several other spiral galaxies. In the case of the Milky Way, many objects can be used to determine the gradients, such as HII regions, B stars, Cepheids, open…

Astrophysics of Galaxies · Physics 2015-05-14 W. J. Maciel , R. D. D. Costa