Results 41 to 50 of about 119 (87)

Rare Event Classification with Weighted Logistic Regression for Identifying Repeating Fast Radio Bursts

The Astrophysical Journal
An important task in the study of fast radio bursts (FRBs) remains the automatic classification of repeating and nonrepeating sources based on their morphological properties. We propose a statistical model that considers a modified logistic regression to
Antonio Herrera-Martin, Radu V. Craiu, Gwendolyn M. Eadie, David C. Stenning, Derek Bingham, B. M. Gaensler, Ziggy Pleunis, Paul Scholz, Ryan Mckinven, Bikash Kharel, Kiyoshi W. Masui   +10 more
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Distributions of Wide Binary Stars in Theory and in Gaia Data. II. Reconstruction of Sample Probability Density of True Orbit Sizes

The Astronomical Journal
Wide binary stars are important for testing alternative models of gravitation in the weak-field regime and understanding the statistical outcomes of dynamical interactions in the general Galactic field. The Gaia mission’s collection of weakly bound pairs
Valeri V. Makarov
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USmorph: An Updated Framework of Automatic Classification of Galaxy Morphologies and Its Application to Galaxies in the COSMOS Field

The Astrophysical Journal Supplement Series
Morphological classification conveys abundant information on the formation, evolution, and environment of galaxies. In this work, we refine a two-step galaxy morphological classification framework ( USmorph ), which employs a combination of unsupervised ...
Jie Song, GuanWen Fang, Shuo Ba, Zesen Lin, Yizhou Gu, Chichun Zhou, Tao Wang, Cai-Na Hao, Guilin Liu, Hongxin Zhang, Yao Yao, Xu Kong   +11 more
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Locating Holes in Data with Topological Data Analysis and Applications in Astronomy

, 2019
Astronomical surveys with planets, stars, or galaxies are available from different types of instruments. Analysis of these data have been considered as statistical challenges in the modern field of astrostatistics. This thesis lies at the intersection of
Xu, Xin
core  

Dual-coding Contrastive Learning Based on the ConvNeXt and ViT Models for Morphological Classification of Galaxies in COSMOS-Web

The Astrophysical Journal Supplement Series
In our previous works, we proposed a machine learning framework named USmorph for efficiently classifying galaxy morphology. In this study, we propose a self-supervised method called contrastive learning to upgrade the unsupervised machine learning (UML)
Shiwei Zhu, Guanwen Fang, Chichun Zhou, Jie Song, Zesen Lin, Yao Dai, Xu Kong   +6 more
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Robustness Analysis of USmorph. II. Optimizing Feature Extraction, Dimensionality Reduction, and Clustering for Unsupervised Galaxy Morphology Classification

The Astrophysical Journal
We conduct a systematic robustness analysis of the unsupervised machine learning module within the hybrid framework USmorph . This module automatically discovers morphological structures from large-scale galaxy images, forming the foundation of the ...
Guanwen Fang, Xiaolei Yin, Yirui Zheng, Zesen Lin, Shiwei Zhu, Jie Song, Chichun Zhou, Xu Kong   +7 more
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Robustness Analysis of USmorph. I. Generalization Efficiency of Unsupervised Strategies and Supervised Learning in Galaxy Morphological Classification

The Astrophysical Journal
We conduct a systematic robustness analysis of the hybrid machine learning framework USmorph , which integrates unsupervised and supervised learning for galaxy morphological classification.
Shiwei Zhu, Guanwen Fang, Yao Dai, Chichun Zhou, Yirui Zheng, Jie Song, Shiying Lu, Xu Kong   +7 more
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A Parameter-masked Mock Data Challenge for Beyond-two-point Galaxy Clustering Statistics

The Astrophysical Journal
The past few years have seen the emergence of a wide array of novel techniques for analyzing high-precision data from upcoming galaxy surveys, which aim to extend the statistical analysis of galaxy clustering data beyond the linear regime and the ...
The Beyond-2pt Collaboration, Elisabeth Krause, Yosuke Kobayashi, Andrés N. Salcedo, Mikhail M. Ivanov, Tom Abel, Kazuyuki Akitsu, Raul E. Angulo, Giovanni Cabass, Sofia Contarini, Carolina Cuesta-Lazaro, ChangHoon Hahn, Nico Hamaus, Donghui Jeong, Chirag Modi, Nhat-Minh Nguyen, Takahiro Nishimichi, Enrique Paillas, Marcos Pellejero Ibañez, Oliver H. E. Philcox, Alice Pisani, Fabian Schmidt, Satoshi Tanaka, Giovanni Verza, Sihan Yuan, Matteo Zennaro   +25 more
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Influence of Density Distribution on Synchrotron Polarization Dispersion in Magnetized Interstellar Medium

The Astrophysical Journal
Faraday rotation measure (RM) synthesis is a well-known approach originated in B. J. Burn and later developed by M. A. Brentjens & A. G. de Bruyn for studying magnetic fields.
Ya-Wen Xiao, Jian-Fu Zhang, Alex Lazarian, Dmitri Pogosyan   +3 more
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Estimating Galaxy Parameters with Self-organizing Maps and the Effect of Missing Data

The Astronomical Journal
The current and upcoming large data volume galaxy surveys require the use of machine-learning techniques to maximize their scientific return. This study explores the use of Self-Organizing Maps (SOMs) to estimate galaxy parameters with a focus on ...
Valentina La Torre, Anna Sajina, Andy D. Goulding, Danilo Marchesini, Rachel Bezanson, Alan N. Pearl, Laerte Sodré Jr.   +6 more
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