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Related papers: Imbalanced learning for RR Lyrae stars

200 papers

In our previous works, we proposed a machine learning framework named \texttt{USmorph} for efficiently classifying galaxy morphology. In this study, we propose a self-supervised method called contrastive learning to upgrade the unsupervised…

Astrophysics of Galaxies · Physics 2025-12-19 Shiwei Zhu , Guanwen Fang , Chichun Zhou , Jie Song , Zesen Lin , Yao Dai , Xu Kong

Ground-based optical surveys such as PanSTARRS, DES, and LSST, will produce large catalogs to limiting magnitudes of r > 24. Star-galaxy separation poses a major challenge to such surveys because galaxies---even very compact…

Instrumentation and Methods for Astrophysics · Physics 2015-06-05 Ross Fadely , David W. Hogg , Beth Willman

We present mean horizontal branch absolute magnitudes and iron abundances for a sample of 39 globular clusters. These quantities were calculated in an unprecedented homogeneous fashion based on Fourier decomposition of ligt curves of RR…

Solar and Stellar Astrophysics · Physics 2023-06-05 Armando Arellano Ferro

Machine learning has increasingly gained more popularity with its incredibly powerful ability to make predictions or calculated suggestions for large amounts of data. We apply the machine learning classification to 85,613,922 objects in the…

Solar and Stellar Astrophysics · Physics 2018-10-17 Yu Bai , JiFeng Liu , Song Wang

We present results from a GALEX ultraviolet (UV) survey of a complete sample of 390 galaxies within ~11 Mpc of the Milky Way. The UV data are a key component of the composite Local Volume Legacy (LVL), an ultraviolet-to-infrared imaging…

We describe a new method to identify young, late-type stars within ~150 pc of the Earth that employs visual or near-infrared data and the GALEX GR4/5 database. For spectral types later than K5, we demonstrate that the ratio of GALEX…

Solar and Stellar Astrophysics · Physics 2011-02-02 David R. Rodriguez , M. S. Bessell , B. Zuckerman , Joel H. Kastner

(Abridged) We have surveyed four globular clusters in the Fornax dwarf galaxy for RR Lyrae stars, using archival HST observations. We identify 197 new RR Lyrae stars in these four clusters. Despite the short observational baseline, we…

Astrophysics · Physics 2009-11-10 A. D. Mackey , G. F. Gilmore

We have combined optical and near-infrared data of known RR Lyrae (RRL) stars in the bulge in order to study the spatial distribution of its metal-poor component by measuring precise reddening values and distances of 7663 fundamental-mode…

Astrophysics of Galaxies · Physics 2015-01-21 I. Dékány , D. Minniti , M. Catelan , M. Zoccali , R. K. Saito , M. Hempel , O. A. Gonzalez

Upcoming synoptic surveys are set to generate an unprecedented amount of data. This requires an automatic framework that can quickly and efficiently provide classification labels for several new object classification challenges. Using data…

Instrumentation and Methods for Astrophysics · Physics 2019-07-31 Zafiirah Hosenie , Robert Lyon , Benjamin Stappers , Arrykrishna Mootoovaloo

Globular clusters (GCs) have been at the heart of many longstanding questions in many sub-fields of astronomy and, as such, systematic identification of GCs in external galaxies has immense impacts. In this study, we take advantage of M87's…

The discovery of very distant stars in the halo of the Milky Way provides valuable tracers on the Milky Way mass and its formation. Beyond 100 kpc from the Galactic center, most of the stars are likely to be in faint dwarf galaxies or tidal…

Motivated by the vast gap between photometric and spectroscopic data volumes, there is great potential in using 5D kinematic information to identify and study substructures of the Milky Way. We identify substructures in the Galactic halo…

Light curves serve as a valuable source of information on stellar formation and evolution. With the rapid advancement of machine learning techniques, it can be effectively processed to extract astronomical patterns and information. In this…

Instrumentation and Methods for Astrophysics · Physics 2025-03-18 Yu-Yang Li , Yu Bai , Cunshi Wang , Mengwei Qu , Ziteng Lu , Roberto Soria , Jifeng Liu

There are several supervised machine learning methods used for the application of automated morphological classification of galaxies; however, there has not yet been a clear comparison of these different methods using imaging data, or a…

This work brings together some of the most common machine learning (ML) algorithms, and the objective is to make a comparison at the level of obtained results from a set of unbalanced data. This dataset is composed of almost 17 thousand…

RR Lyrae stars being distance indicators and tracers of old population serve as excellent probes of the structure, formation, and evolution of our Galaxy. Thousands of them are being discovered in ongoing wide-field surveys. The OGLE…

Astrophysics of Galaxies · Physics 2016-09-07 Pawel Pietrukowicz , OGLE collaboration

Machine learning has become a popular tool to help us make better decisions and predictions, based on experiences, observations and analysing patterns within a given data set without explicitly functions. In this paper, we describe an…

Solar and Stellar Astrophysics · Physics 2020-02-19 Yu Bai , JiFeng Liu , YiLun Wang , Song Wang

We present results from an analysis of $\sim$ 29,000 RR Lyrae stars located in the Large Magellanic Cloud (LMC). For these objects, near-infrared time-series photometry from the VISTA survey of the Magellanic Clouds system (VMC) and optical…

We identify the RR Lyrae and delta Scuti (DSCT) stars in three catalogs of GALEX variable sources. The NUV amplitude of RR Lyrae stars is about twice that in V-band, so we find a larger percentage of low amplitude variables than catalogs…

Solar and Stellar Astrophysics · Physics 2015-06-22 T. D. Kinman , Warren R. Brown