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Related papers: Cepheid Kinematics and the Galactic Warp

200 papers

The projection factor (p), which converts the radial velocity to pulsational velocity, is an important parameter in the Baade-Wesselink (BW) type analysis and distance scale work. The p-factor is either adopted as a constant or linearly…

Solar and Stellar Astrophysics · Physics 2015-06-05 Chow-Choong Ngeow , Hilding R. Neilson , Nicolas Nardetto , Massimo Marengo

We have selected a sample of 326 young $(\log t<8)$ open star clusters with the proper motions and distances calculated by various authors from Gaia DR2 data. The mean values of their line-of-sight velocities have also been taken from…

Astrophysics of Galaxies · Physics 2019-03-25 V. V. Bobylev , A. T. Bajkova

Hydrodynamic computations of nonlinear Cepheid pulsation models with periods from 20 to 100 day on the evolutionary stage of core helium burning were carried out. Equations of radiation hydrodynamics and time--dependent convection were…

Solar and Stellar Astrophysics · Physics 2019-07-03 Yu. A. Fadeyev

Based on observations of NGC 300, obtained with the Wide-Field Camera at the 2.2 m ESO/MPI telescope during 29 nights spread over a 5.3 month interval, 117 Cepheids and 12 Cepheid candidates were found which cover the period range from 115…

Astrophysics · Physics 2007-05-23 G. Pietrzy{ń}ski , W. Gieren , P. Fouque , F. Pont

We have studied the kinematic properties of the candidates for hot subdwarfs (HSDs) selected by Geier et al. from the Gaia DR2 catalogue. We have used a total of 12 515 stars with relative trigonometric parallax errors less than 30\%. The…

Astrophysics of Galaxies · Physics 2019-10-03 V. V. Bobylev , A. T. Bajkova

The proper motions of OB-associations computed using the old (Hipparcos 1997} and new (van Leeuwen 2007) reductions of the Hipparcos data are in a good agreement with each other. The Galactic rotation curve derived from an analysis of…

Astrophysics of Galaxies · Physics 2009-11-18 A. M. Melnik , A. K. Dambis

The rationale behind recent calibrations of the Cepheid PL relation using the Wesenheit formulation is reviewed and reanalyzed, and it is shown that recent conclusions regarding a possible change in slope of the PL relation for short-period…

Astrophysics of Galaxies · Physics 2014-11-20 David G. Turner

The angular-momentum distribution of classical Cepheids in the outer Milky Way disc is bi-modal with a gap at $L_\mathrm{gap}=2950\,\mathrm{km}\,\mathrm{s}^{-1}\,\mathrm{kpc}$, corresponding to $R=13\,\mathrm{kpc}$, while no similar feature…

Astrophysics of Galaxies · Physics 2022-12-14 Marcin Semczuk , Walter Dehnen , Ralph Schoenrich , E. Athanassoula

The evolution of the parameters of the residual velocity ellipsoid of hot subdwarfs (HSDs) with their position relative to the Galactic plane is traced, using the HSDs selected by Geier et al. from the Gaia DR2 catalog. Parameters of the…

Astrophysics of Galaxies · Physics 2019-10-01 V. V. Bobylev , A. T. Bajkova

Cepheids have been observed in NGC 5236 (M 83) using the ANTU (UT1) 8.2 meter telescope of the ESO VLT with FORS1. Observations over 34 epochs in V and I have been made between January 2000 and July 2001. Twelve Cepheid candidates have…

Astrophysics · Physics 2009-11-07 Frank Thim , G. A. Tammann , A. Saha , A. Dolphin , Allan Sandage , E. Tolstoy , Lukas Labhardt

Based on data on Galactic masers with measured trigonometric parallaxes, we have tested a nonlinear model of Galactic rotation using generalized Oort formulas. This model is shown to yield pretty good results up to heliocentric distances of…

Astrophysics of Galaxies · Physics 2014-11-11 V. V. Bobylev , A. T. Bajkova

Polaris is the nearest and brightest classical Cepheid, and pulsates with a period of about 4 days. It has long been known as a single-lined spectroscopic binary with an orbital period of 30 yr. Historical photometric and spectroscopic…

Solar and Stellar Astrophysics · Physics 2023-09-08 Guillermo Torres

We point out that the absolute magnitude of the Galactic Cepheids, which have been used for local calibrations for Cepheid period-luminosity relation, shows an unexpectedly large metal abundance effect. This indicates that either Cepheids…

Astrophysics · Physics 2007-05-23 M. Sekiguchi , M. Fukugita

We recently showed that rotation significantly affects most observable Cepheid quantities, and that rotation, in combination with the evolutionary status of the star, can resolve the long-standing Cepheid mass discrepancy problem. We…

Solar and Stellar Astrophysics · Physics 2015-06-22 Richard I. Anderson , Sylvia Ekström , Cyril Georgy , Georges Meynet , Nami Mowlavi , Laurent Eyer

We present a first results from a long-term program of a radial velocity study of Cepheid Polaris (F7 Ib) aimed to find amplitude and period of pulsations and nature of secondary periodicities. 264 new precise radial velocity measurements…

Astrophysics · Physics 2009-11-13 Byeong-Cheol Lee , David. E. Mkrtichian , Inwoo Han , Myeong-Gu Park , Kang-Min Kim

The stellar velocity ellipsoid of the solar neighbour is re-examined using intermediate-old mono-abundances stellar groups with high quality chemistry data together with parallaxes and proper motions from Gaia DR1. We find the average…

Astrophysics of Galaxies · Physics 2017-12-20 Borja Anguiano , Steven R. Majewski , Kenneth C. Freeman , Arik W. Mitschang , Martin C. Smith

Context. Binary Cepheids play an important role in investigating the calibration of the classical Cepheid period-luminosity relationship. Therefore a thorough study of individual Cepheids belonging to binary systems is necessary. Aims. Our…

Solar and Stellar Astrophysics · Physics 2023-12-20 B. Cseh , G. Csörnyei , L. Szabados , B. Csák , J. Kovács , L. Kriskovics , A. Pál

We derive the vertical velocities of disk stars in the range of Galactocentric radii of R=5-16 kpc within 2 kpc in height from the Galactic plane. This kinematic information is connected to dynamical aspects in the formation and evolution…

Astrophysics of Galaxies · Physics 2014-12-10 M. Lopez-Corredoira , H. Abedi , F. Garzon , F. Figueras

The nature of our Milky Way Galaxy is reexamined from an eclectic point of view. Evidence for a central bar, for example, is not reflected in the distribution of RR Lyrae variables in the central bulge [4,5], and it is not clear if either a…

Astrophysics of Galaxies · Physics 2015-06-17 David G. Turner

We determine Period-Luminosity relations for Milky Way Cepheids in the optical and near-IR bands. These relations can be used directly as reference for extra-galactic distance determination to Cepheid populations with solar metallicity, and…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 J. Storm , W. Gieren , P. Fouque , T. G. Barnes , G. Pietrzynski , N. Nardetto , M. Weber , T. Granzer , K. Strassmeier