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Machine learning is starting to be used in almost every industry and academic research, and solar physics is no exception. A newly developed machine learning model named MagNet helps us to tackle some of the most serious challenges in data…

Solar and Stellar Astrophysics · Physics 2026-02-27 Aryiadna Yesmanchyk , Yan Xu , Jason T. L. Wang , Haodi Jiang , Chunhui Xu , Haimin Wang

We search for quasi-stellar objects (QSOs) in a wide area of the south ecliptic pole (SEP) field, which has been and will continue to be intensively explored through various space missions. For this purpose, we obtain deep broadband optical…

We describe a large sample of 598 galaxy clusters and rich groups discovered in the data of the Faint Sky Variability Survey. The clusters have been identified using a fully automated, semi-parametric technique based on a maximum likelihood…

Astrophysics · Physics 2009-11-11 Ilona K. Soechting , Mark E. Huber , Roger G. Clowes , Steve B. Howell

We present a variability study of 4646 massive stars in the Small Magellanic Cloud (SMC) with known spectral types from the catalog of Bonanos et al. (2010) using the light curves from the OGLE-III database. The goal is to exploit the time…

We present an extensive and well-characterized Chandra X-ray Galaxy Catalog (CGC) of 8557 galaxy candidates in the redshift range z ~ 0.04 - 0.7, optical luminosity 1010 - 1011 Lro, and X-ray luminosity (0.5-7 keV) LX = 2x1040 - 2x1043 erg…

Modern variable selection procedures make use of penalization methods to execute simultaneous model selection and estimation. A popular method is the LASSO (least absolute shrinkage and selection operator), the use of which requires…

Methodology · Statistics 2023-01-12 Meadhbh O'Neill , Kevin Burke

Distinguishing active galaxies from star-forming galaxies is essential for understanding galaxy evolution. Diagnostic methods like the BPT (Baldwin, Phillips, and Terlevich) diagram use optical emission-line ratios to separate galaxies.…

Astrophysics of Galaxies · Physics 2026-03-26 Farideh Mazoochi , Reihaneh Karimi , Mohammad Hossein Zhoolideh Haghighi , Fatemeh Tabatabaei

One Class Slab Support Vector Machines (OCSSVM) have turned out to be better in terms of accuracy in certain classes of classification problems than the traditional SVMs and One Class SVMs or even other One class classifiers. This paper…

Machine Learning · Computer Science 2024-09-05 Bagesh Kumar , Ayush Sinha , Sourin Chakrabarti , O. P. Vyas

In the field of big data analytics, the search for efficient subdata selection methods that enable robust statistical inferences with minimal computational resources is of high importance. A procedure prior to subdata selection could…

Methodology · Statistics 2024-11-12 Vasilis Chasiotis , Lin Wang , Dimitris Karlis

We present a catalog of quasars selected from broad-band photometric ugri data of the Kilo-Degree Survey Data Release 3 (KiDS DR3). The QSOs are identified by the random forest (RF) supervised machine learning model, trained on SDSS DR14…

Instrumentation and Methods for Astrophysics · Physics 2019-04-10 S. Nakoneczny , M. Bilicki , A. Solarz , A. Pollo , N. Maddox , C. Spiniello , M. Brescia , N. R. Napolitano

The spatial error model (SEM) is a type of simultaneous autoregressive (SAR) model for analysing spatially correlated data. Markov chain Monte Carlo (MCMC) is one of the most widely used Bayesian methods for estimating SEM, but it has…

Methodology · Statistics 2024-06-14 Anjana Wijayawardhana , David Gunawan , Thomas Suesse

LSST will provide galaxy cluster catalogs up to z$\sim$1 that can be used to constrain cosmological models once their selection function is well-understood. We have applied the deep convolutional network YOLO for CLuster detection (YOLO-CL)…

As large language model agents tackle increasingly complex long-horizon tasks, effective post-training becomes critical. Prior work faces fundamental challenges: outcome-only rewards fail to precisely attribute credit to intermediate steps,…

Computation and Language · Computer Science 2026-04-30 Mukai Li , Qingcheng Zeng , Tianqing Fang , Zhenwen Liang , Linfeng Song , Qi Liu , Haitao Mi , Dong Yu

Several recent works have focused on the search for bright, high-z quasars (QSOs) in the South. Among them, the QUasars as BRIght beacons for Cosmology in the Southern hemisphere (QUBRICS) survey has now delivered hundreds of new…

Identifying stars belonging to different classes is vital in order to build up statistical samples of different phases and pathways of stellar evolution. In the era of surveys covering billions of stars, an automated method of identifying…

Instrumentation and Methods for Astrophysics · Physics 2024-10-31 Sean Enis Cody , Sebastian Scher , Iain McDonald , Albert Zijlstra , Emma Alexander , Nick L. J. Cox

Context. In modern astronomy, machine learning has proved to be efficient and effective to mine the big data from the newesttelescopes. Spectral surveys enable us to characterize millions of objects, while long exposure time observations…

Galaxy morphology, a key tracer of the evolution of a galaxy's physical structure, has motivated extensive research on machine learning techniques for efficient and accurate galaxy classification. The emergence of quantum computers has…

Astrophysics of Galaxies · Physics 2023-11-08 Mohammad Hassan Hassanshahi , Marcin Jastrzebski , Sarah Malik , Ofer Lahav

The MACHO Project is a search for dark matter in the form of massive compact halo objects (Machos). Photometric monitoring of millions of stars in the Large Magellanic Cloud (LMC), Small Magellanic Cloud (SMC), and Galactic bulge is used to…

Modern time-domain surveys continuously monitor large swaths of the sky to look for astronomical variability. Astrophysical discovery in such data sets is complicated by the fact that detections of real transient and variable sources are…

Instrumentation and Methods for Astrophysics · Physics 2015-06-11 Henrik Brink , Joseph W. Richards , Dovi Poznanski , Joshua S. Bloom , John Rice , Sahand Negahban , Martin Wainwright

Morphological classification is a key piece of information to define samples of galaxies aiming to study the large-scale structure of the universe. In essence, the challenge is to build up a robust methodology to perform a reliable…

Instrumentation and Methods for Astrophysics · Physics 2019-11-05 P. H. Barchi , R. R. de Carvalho , R. R. Rosa , R. Sautter , M. Soares-Santos , B. A. D. Marques , E. Clua , T. S. Gonçalves , C. de Sá-Freitas , T. C. Moura