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Related papers: Imbalanced learning for RR Lyrae stars

200 papers

Extragalactic globular clusters (GCs) are important tracers of galaxy formation and evolution. Obtaining GC catalogues from photometric data involves several steps which will likely become too time-consuming to perform on the large data…

Astrophysics of Galaxies · Physics 2022-07-20 Dominik Dold , Katja Fahrion

Many studies have shown that RR Lyrae variable stars (RRL) are powerful stellar tracers of Galactic halo structure and satellite galaxies. The Dark Energy Survey (DES), with its deep and wide coverage (g ~ 23.5 mag) in a single exposure;…

RR Lyrae (RRL) variable stars are cornerstone distance indicators. In particular, double-mode RR Lyrae (RRd) stars enable period--luminosity relations (PLRs) that are less sensitive to metallicity, reducing systematic biases in distance…

Solar and Stellar Astrophysics · Physics 2025-10-10 Jianxing Zhang , Xiaodian Chen , Shu Wang , Jiyu Wang , Licai Deng

The Convex Hull algorithm is one of the most important algorithms in computational geometry, with many applications such as in computer graphics, robotics, and data mining. Despite the advances in the new algorithms in this area, it is…

Distributed, Parallel, and Cluster Computing · Computer Science 2023-03-21 Roberto Carrasco , Héctor Ferrada , Cristóbal A. Navarro , Nancy Hitschfeld

RR Lyrae stars are excellent tracers of stellar populations for old, metal-poor components in the Milky Way Galaxy and the Local Group. Their luminosities have a metallicity-dependence, but determining spectroscopic [Fe/H] metallicities for…

We have revisited the problem of metallicity prediction of RR Lyrae stars from their near-infrared light curves in the Cousins I waveband. Our study is based on high-quality time-series photometry and state-of-the-art high-resolution…

Solar and Stellar Astrophysics · Physics 2021-10-20 István Dékány , Eva K. Grebel , Grzegorz Pojmański

Full space velocities are computed for a sample of 130 nearby RR Lyrae variables using both ground-based and Hipparcos proper motions. In many cases proper motions from multiple sources have been averaged to produce a significant…

Astrophysics · Physics 2009-10-30 John C. Martin , Heather L. Morrison

We report the results of CCD V and r photometry of the globular cluster NGC 5466. The difference image analysis technique adopted in this work has resulted in accurate time series photometry even in crowded regions of the cluster enabling…

Astrophysics · Physics 2009-11-13 A. Arellano Ferro , V. Rojas Lopez , Sunetra Giridhar , D. M. Bramich

We used moderately high-resolution, high S/N spectra to study the chemical composition of 10 field ab-type RR Lyrae stars. A new temperature scale was determined from literature Infrared Flux Method measures of subdwarfs and the Kurucz…

Astrophysics · Physics 2009-11-24 G. Clementini , E. Carretta , R. Gratton , R. Merighi , J. R. Mould , J. K. McCarthy

Like Hipparcos, Gaia is designed to give absolute parallaxes, independent of any astrophysical reference system. And indeed, Gaia's internal zero-point error for parallaxes is likely to be smaller than any individual parallax error.…

Solar and Stellar Astrophysics · Physics 2017-03-15 Andrew Gould , Juna A. Kollmeier

The structure and kinematics of the old component of the Galactic bulge are still a matter of debate. The bulk of the bulge as traced by red clump stars includes two main components, which are usually identified as the metal-rich and…

RR Lyrae stars are a common, dependable Population II distance indicator, and provide an independent tracer of early star formation. Here, we utilize archival HST/ACS and JWST/NIRCam observations of the nearby dwarf star-forming galaxy WLM…

(abridged) Mass loss is a key parameter in the evolution of massive stars, with discrepancies between theory and observations and with unknown importance of the episodic mass loss. To address this we need increased numbers of classified…

Solar and Stellar Astrophysics · Physics 2022-10-19 Grigoris Maravelias , Alceste Z. Bonanos , Frank Tramper , Stephan de Wit , Ming Yang , Paolo Bonfini

We present a sample of 148 candidate RR Lyrae stars selected from Sloan Digital Sky Survey (SDSS) commissioning data for about 100 deg2 of sky surveyed twice with Delta(t) = 1.9946 days. Although the faint magnitude limit of the SDSS allows…

Astrophysics · Physics 2009-10-31 Z. Ivezic , J. Goldston , K. Finlator

High reddening near the Galactic plane hampers observations and proper characterization of the globular clusters (GCs) located toward the inner regions of the Milky Way. The VISTA Variables in the Via Lactea (VVV) survey observed the…

We determine the period-magnitude relations of RR Lyrae stars in 13 photometric bandpasses from 0.4 to 12 {\mu}m using timeseries observations of 134 stars. The Bayesian formalism, extended from our previous work to include the effects of…

Solar and Stellar Astrophysics · Physics 2014-06-10 Christopher R. Klein , Joshua S. Bloom

Context. RR Lyrae stars are useful standard candles allowing one to derive accurate distances for old star clusters. Based on the recent catalogues from OGLE-IV and Gaia Early Data Release 3 (EDR3), the distances can be improved for a few…

Astrophysics of Galaxies · Physics 2022-01-26 R. A. P. Oliveira , S. Ortolani , B. Barbuy , L. O. Kerber , F. F. S. Maia , E. Bica , S. Cassisi , S. O. Souza , A. Pérez-Villegas

Time-domain astronomy is progressing rapidly with the ongoing and upcoming large-scale photometric sky surveys led by the Vera C. Rubin Observatory project (LSST). Billions of variable sources call for better automatic classification…

Instrumentation and Methods for Astrophysics · Physics 2023-09-26 Zihan Kang , Yanxia Zhang , Jingyi Zhang , Changhua Li , Minzhi Kong , Yongheng Zhao , Xue-Bing Wu

We report the discovery of distant RR Lyrae stars, including the most distant known in the Milky Way, using data taken in the $g-$band with the Dark Energy Camera as part of the High cadence Transient Survey (HiTS; 2014 campaign). We detect…

RR Lyrae stars in the Milky Way are good tracers to study the kinematic behaviour and spatial distribution of older stellar populations. A recently established well documented sample of 217 RR Lyr stars with V<12.5 mag, has been used to…

Astrophysics · Physics 2009-11-11 Gisela Maintz , Klaas S. de Boer