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Related papers: Optimal strategies for identifying quasars in DESI

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Herein, we present a system for hyperspectral image segmentation that utilizes multiple class--based denoising autoencoders which are efficiently trained. Moreover, we present a novel hyperspectral data augmentation method for labelled HSI…

Computer Vision and Pattern Recognition · Computer Science 2018-07-30 John E. Ball , Pan Wei

We detect the cross-correlation between 2.7 million DESI quasar targets across 14,700 deg$^2$ (180 quasars deg$^{-2}$) and Planck 2018 CMB lensing at $\sim$30$\sigma$. We use the cross-correlation on very large scales to constrain local…

Weak lensing studies typically require excellent seeing conditions for the purpose of maximizing the number density of well-resolved galaxy images. It is interesting to ask to what extent the seeing size limits the usefulness of the…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-14 Jun Zhang , Cong Liu , Pedro Alonso Vaquero , Hekun Li , Haoran Wang , Zhi Shen , Fuyu Dong

MLPQNA stands for Multi Layer Perceptron with Quasi Newton Algorithm and it is a machine learning method which can be used to cope with regression and classification problems on complex and massive data sets. In this paper we give the…

Instrumentation and Methods for Astrophysics · Physics 2015-06-16 M. Brescia , S. Cavuoti , R. D'Abrusco , G. Longo , A. Mercurio

Remote sensing image (RSI) denoising is an important topic in the field of remote sensing. Despite the impressive denoising performance of RSI denoising methods, most current deep learning-based approaches function as black boxes and lack…

Computer Vision and Pattern Recognition · Computer Science 2025-06-02 Jingjing Liu , Jiashun Jin , Xianchao Xiu , Jianhua Zhang , Wanquan Liu

Spectroscopy represents the ideal observational method to maximally extract information from galaxies regarding their star formation and chemical enrichment histories. However, absorption spectra of galaxies prove rather challenging at high…

Instrumentation and Methods for Astrophysics · Physics 2025-10-10 Oliver Camilleri , Zahra Sharbaf , Ignacio Ferreras

We present observed mid-infrared and optical colors and composite spectral energy distributions (SEDs) of type 1 (broad-line) and 2 (narrow-line) quasars selected from Sloan Digital Sky Survey (SDSS) spectroscopy. A significant fraction of…

Astrophysics of Galaxies · Physics 2017-11-08 Ryan C. Hickox , Adam D. Myers , Jenny E. Greene , Kevin N. Hainline , Nadia L. Zakamska , Michael A. DiPompeo

We apply one of lazy learning methods named k-nearest neighbor algorithm (kNN) to estimate the photometric redshifts of quasars, based on various datasets from the Sloan Digital Sky Survey (SDSS), UKIRT Infrared Deep Sky Survey (UKIDSS) and…

Instrumentation and Methods for Astrophysics · Physics 2017-03-22 Zhang Yanxia , Ma He , Peng Nanbo , Zhao Yongheng , Wu Xue-bing

With recent advancements in the development of artificial intelligence applications using theories and algorithms in machine learning, many accurate models can be created to train and predict on given datasets. With the realization of the…

Machine Learning · Computer Science 2024-03-29 Pei Xi , Lin

Past few years have witnessed exponential growth of interest in deep learning methodologies with rapidly improving accuracies and reduced computational complexity. In particular, architectures using Convolutional Neural Networks (CNNs) have…

Computer Vision and Pattern Recognition · Computer Science 2018-05-11 Sai Samarth R Phaye , Apoorva Sikka , Abhinav Dhall , Deepti Bathula

We identify 885,503 type 1 quasar candidates to i<22 using the combination of optical and mid-IR photometry. Optical photometry is taken from the Sloan Digital Sky Survey-III: Baryon Oscillation Spectroscopic Survey (SDSS-III/BOSS), while…

Image recognition is one of the primary applications of machine learning algorithms. Nevertheless, machine learning models used in modern image recognition systems consist of millions of parameters that usually require significant…

The recently commissioned Dark Energy Spectroscopic Instrument (DESI) will measure the expansion history of the Universe using the Baryon Acoustic Oscillation technique. The spectra of 35 million galaxies and quasars over 14000 sqdeg will…

Application of underwater robots are on the rise, most of them are dependent on sonar for underwater vision, but the lack of strong perception capabilities limits them in this task. An important issue in sonar perception is matching image…

Computer Vision and Pattern Recognition · Computer Science 2021-08-03 Arka Mallick , Paul Plöger , Matias Valdenegro-Toro

We present the high-$z$ quasar candidate archive (HzQCA), summarizing the spectroscopic observations of 174 $z\gtrsim5$ quasar candidates using Keck/LRIS, Keck/MOSFIRE, and Keck/NIRES. We identify 7 candidates as $z\sim 6$ quasars 3 of them…

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…

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

Hyperspectral image (HSI) classification is an important task in many applications, such as environmental monitoring, medical imaging, and land use/land cover (LULC) classification. Due to the significant amount of spectral information from…

Computer Vision and Pattern Recognition · Computer Science 2026-05-06 Sertac Kilickaya , Mete Ahishali , Fahad Sohrab , Turker Ince , Moncef Gabbouj