English
Related papers

Related papers: Semi-Supervised Learning for Lensed Quasar Detecti…

200 papers

Over the last two decades, around 300 quasars have been discovered at $z\gtrsim6$, yet only one has identified as being strongly gravitationally lensed. We explore a new approach -- enlarging the permitted spectral parameter space, while…

Strongly lensed quasars provide valuable insights into the rate of cosmic expansion, the distribution of dark matter in foreground deflectors, and the characteristics of quasar hosts. However, detecting them in astronomical images is…

Quasars experiencing strong lensing offer unique viewpoints on subjects related to the cosmic expansion rate, the dark matter profile within the foreground deflectors, and the quasar host galaxies. Unfortunately, identifying them in…

Gravitational lens systems containing lensed quasars are important as cosmological probes, as diagnostics of structural properties of the lensing galaxies and as tools to study the quasars themselves. The largest lensed quasar sample is the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Neal Jackson , Hayden Rampadarath , Eran O. Ofek , Masamune Oguri , Min-Su Shin

Recent advances in quantum technology have led to the development and the manufacturing of programmable quantum annealers that promise to solve certain combinatorial optimization problems faster than their classical counterparts.…

Quantum Physics · Physics 2021-05-26 Yu-Lin Zheng , Wen Zhang , Cheng Zhou , Wei Geng

Gravitationally lensed quasars are useful for studying astrophysics and cosmology, and enlarging the sample size of lensed quasars is important for multiple studies. In this work, we develop a lens search algorithm for four-image (quad)…

The time delay between multiple images of strongly lensed quasars is a powerful tool for measuring the Hubble constant (H0). To achieve H0 measurements with higher precision and accuracy using the time delay, it is crucial to expand the…

Cosmology and Nongalactic Astrophysics · Physics 2023-12-14 C. Dawes , C. Storfer , X. Huang , G. Aldering , A. Cikota , A. Dey , D. J. Schlegel

The field of Astronomy requires the collection and assimilation of vast volumes of data. The data handling and processing problem has become severe as the sheer volume of data produced by scientific instruments each night grows…

Machine Learning · Computer Science 2020-10-05 Aniruddh Herle , Janamejaya Channegowda , Dinakar Prabhu

Gravitationally strongly lensed quasars (SL-QSO) offer invaluable insights into cosmological and astrophysical phenomena. With the data from ongoing and next-generation surveys, thousands of SL-QSO systems can be discovered expectedly,…

Gravitationally lensed (GL) quasars are brighter than their unlensed counterparts and produce images with distinctive morphological signatures. Past searches and target selection algorithms, in particular the Sloan Quasar Lens Search…

Astrophysics of Galaxies · Physics 2015-06-23 Adriano Agnello , Brandon C. Kelly , Tommaso Treu , Philip J. Marshall

This work tackles the problem of semi-supervised learning of image classifiers. Our main insight is that the field of semi-supervised learning can benefit from the quickly advancing field of self-supervised visual representation learning.…

Computer Vision and Pattern Recognition · Computer Science 2019-07-24 Xiaohua Zhai , Avital Oliver , Alexander Kolesnikov , Lucas Beyer

Of the hundreds of $z\gtrsim6$ quasars discovered to date, only one is known to be gravitationally lensed, despite the high lensing optical depth expected at $z\gtrsim6$. High-redshift quasars are typically identified in large-scale surveys…

Semi-supervised learning techniques are gaining popularity due to their capability of building models that are effective, even when scarce amounts of labeled data are available. In this paper, we present a framework and specific tasks for…

Image and Video Processing · Electrical Eng. & Systems 2022-10-05 Antonio Montanaro , Diego Valsesia , Giulia Fracastoro , Enrico Magli

Machine learning methods are increasingly helping astronomers identify new radio pulsars. However, they require a large amount of labelled data, which is time consuming to produce and biased. Here we describe a Semi-Supervised Generative…

Instrumentation and Methods for Astrophysics · Physics 2021-05-14 Vishnu Balakrishnan , David Champion , Ewan Barr , Michael Kramer , Rahul Sengar , Matthew Bailes

Luminous quasars at $z > 6$ are key probes of early supermassive black hole (SMBH) growth, massive galaxy evolution, and intergalactic medium properties during cosmic reionization. However, their discovery is very challenging due to their…

Gravitationally-lensed quasars can be discovered as a by-product of galaxy redshift surveys. Lenses discovered spectroscopically in this way should require less observational effort per event than those found in dedicated lens surveys.…

Astrophysics · Physics 2009-10-31 Daniel J. Mortlock , Rachel L. Webster

Supervised learning is based on the assumption that the ground truth in the training data is accurate. However, this may not be guaranteed in real-world settings. Inaccurate training data will result in some unexpected predictions. In image…

Computer Vision and Pattern Recognition · Computer Science 2022-01-06 Yunhao Yang , Andrew Whinston

Convolution Neural Networks trained for the task of lens finding with similar architecture and training data as is commonly found in the literature are biased classifiers. An understanding of the selection function of lens finding neural…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-21 A. Herle , C. M. O'Riordan , S. Vegetti

In this paper we develop a new unsupervised machine learning technique comprised of a feature extractor, a convolutional autoencoder (CAE), and a clustering algorithm consisting of a Bayesian Gaussian mixture model (BGM). We apply this…

Instrumentation and Methods for Astrophysics · Physics 2020-04-15 Ting-Yun Cheng , Nan Li , Christopher J. Conselice , Alfonso Aragón-Salamanca , Simon Dye , Robert B. Metcalf
‹ Prev 1 2 3 10 Next ›