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Related papers: Imbalanced learning for RR Lyrae stars

200 papers

We discuss the density and radial velocity distributions of over 3000 candidate RR Lyrae stars selected by various methods using Sloan Digital Sky Survey data for about 1000 deg^2 of sky. This is more than 20 times larger sample than…

We applied Stars' Galactic Origin (StarGO) algorithm in 7D space (i.e., [Fe/H], [Mg/Fe], [Al/Fe], $L_{z}$, $J_{r}$, $J_{z}$, $E$) to analyze stars in the inner halo with APOGEE DR17. We identified some known substructures, including…

Astrophysics of Galaxies · Physics 2025-04-03 Zhongcheng Li , Cuihua Du , Haoyang Liu , Dashuang Ye

An efficient separation between dwarfs and giants in surveys of bright stars is important, especially for studies in which distances are estimated through photometric parallax relations. We use the available spectroscopic log g estimates…

Astrophysics of Galaxies · Physics 2015-05-20 Rainer J. Klement , Coryn A. L. Bailer-Jones , Burkhard Fuchs , Hans-Walter Rix , Kester W. Smith

In this paper, a deep convolutional neural network architecture for galaxies classification is presented. The galaxy can be classified based on its features into main three categories Elliptical, Spiral, and Irregular. The proposed deep…

Computer Vision and Pattern Recognition · Computer Science 2017-09-08 Nour Eldeen M. Khalifa , Mohamed Hamed N. Taha , Aboul Ella Hassanien , I. M. Selim

RR Lyrae are a well-known class of pulsating horizontal branch stars widely used as tracers of old, metal-poor stellar populations. However, mounting observational evidence shows that a significant fraction of these stars may be young and…

Solar and Stellar Astrophysics · Physics 2024-01-17 Alexey Bobrick , Giuliano Iorio , Vasily Belokurov , Joris Vos , Maja Vuckovic , Nicola Giacobbo

We use the recently released OGLE-III catalog of 17692 fundamental mode RR Lyr (RRab) stars in the Large Magellanic Cloud (LMC) to investigate the structure of its stellar halo. We apply conservative cuts in period, amplitude and magnitude…

Astrophysics of Galaxies · Physics 2011-02-11 O. Pejcha , K. Z. Stanek

Generative deep learning methods built upon Convolutional Neural Networks (CNNs) provide a great tool for predicting non-linear structure in cosmology. In this work we predict high resolution dark matter halos from large scale, low…

Cosmology and Nongalactic Astrophysics · Physics 2022-04-25 David Schaurecker , Yin Li , Jeremy Tinker , Shirley Ho , Alexandre Refregier

We present results from a study of ab-type RR Lyrae variables in the Large Magellanic Cloud using the extensive dataset from phase III of the Optical Gravitational Lensing Experiment (OGLE). The metallicities of the RR Lyraes, determined…

Astrophysics of Galaxies · Physics 2015-06-15 Rachel Wagner-Kaiser , Ata Sarajedini

We present a new machine learning model for estimating photometric redshifts with improved accuracy for galaxies in Pan-STARRS1 data release 1. Depending on the estimation range of redshifts, this model based on neural networks can handle…

Instrumentation and Methods for Astrophysics · Physics 2021-12-09 Joongoo Lee , Min-Su Shin

An NUV-optical diagram made for sources from the secend Galaxy Evolution Explorer (GALEX) Ultraviolet Variability (GUVV-2) Catalog provide us a method to tentatively classify the unknown GUVV2 sources by their NUV-optical magnitudes. On the…

Solar and Stellar Astrophysics · Physics 2015-05-27 Y. Li , J. Wang , J. Y. Wei , X. T. He

Due to the importance of accurate Fourier parameters, we devise a method that is more appropriate for deriving these parameters on low-quality data than the traditional Fourier fitting. Based on the accurate light curves of 248 fundamental…

Astrophysics · Physics 2009-11-11 G. Kovacs , G. Kupi

We introduce a new technique that uses galaxy clustering to constrain how satellite galaxies lose stellar mass and contribute to the diffuse "intrahalo light" (IHL). We implement two models that relate satellite galaxy stellar mass loss to…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Douglas F. Watson , Andreas A. Berlind , Andrew R. Zentner

Hypervelocity stars (HVSs) are stars with velocities exceeding their local escape velocities. Searching for HVSs and studying their origins can be an important way to study the properties of the Milky Way. In this paper, we utilize precise…

Astrophysics of Galaxies · Physics 2025-10-01 Haozhu Fu , Yang Huang , Huawei Zhang

We have undertaken a dedicated program of automatic source classification in the WISE database merged with SuperCOSMOS scans, comprehensively identifying galaxies, quasars and stars on most of the unconfused sky. We use the Support Vector…

We use spectral energy distribution (SED) fitting to place constraints on the stellar populations of 59 ultra-diffuse galaxies (UDGs) in the low-to-moderate density fields of the MATLAS survey. We use the routine PROSPECTOR, coupled with…

We introduce RACH-Space, an algorithm for labelling unlabelled data in weakly supervised learning, given incomplete, noisy information about the labels. RACH-Space offers simplicity in implementation without requiring hard assumptions on…

Machine Learning · Computer Science 2024-02-05 Woojoo Na , Abiy Tasissa

All galaxies that have been adequately examined so far have shown an extended stellar halo. To search for such a halo in the LMC we have obtained low-resolution spectra for 100 LMC RR Lyrae stars, of which 87 are in the field and 13 in the…

Astrophysics · Physics 2009-11-11 J. Borissova , D. Minniti , M. Rejkuba , D. Alves

The LAMOST spectroscopic survey for Galactic structure and evolution has been in operation since October 2012, following a one-year pilot survey. The pilot survey produced a data release containing over 600,000 stellar spectra. By…

Solar and Stellar Astrophysics · Physics 2013-06-21 F. Yang , L. Deng , C. Liu , J. L. Carlin , H. Jo Newberg , K. Carrell , X. Zhang , Z. Bai , F. Wang , H. Zhang , K. Wang , Y. Xin , Y. Xu , S. Gao , Y. Zhang , J. Li , Y Zhao

This work investigates symbolic regression (SR) as an interpretable alternative to black-box machine learning for the classification of stars, galaxies, and quasars in the Sloan Digital Sky Survey Data Release 17 (SDSS DR17). We conduct a…

Instrumentation and Methods for Astrophysics · Physics 2026-03-02 Rachit Deshpande , Shantanu Desai