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We present results exploring the role that probabilistic deep learning models can play in cosmology from large scale astronomical surveys through estimating the distances to galaxies (redshifts) from photometry. Due to the massive scale of…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-16 Evan Jones , Tuan Do , Bernie Boscoe , Yujie Wan , Zooey Nguyen , Jack Singal

Accurate redshift measurements are essential for studying the evolution of quasi-stellar objects (QSOs) and their role in cosmic structure formation. While spectroscopic redshifts provide high precision, they are impractical for the vast…

Astrophysics of Galaxies · Physics 2025-07-08 Jeremy P. Moss , Stephen J. Curran , Yvette C. Perrott

Photometric redshift estimation is a key requirement for modern large-area surveys, where spectroscopic measurements are observationally prohibitive. Seyfert II galaxies provide a particularly challenging test case due to the combined…

Astrophysics of Galaxies · Physics 2026-04-23 Uzay Aydin

We present photometric redshifts for 1,031 X-ray sources in the X-ATLAS field, using the machine learning technique TPZ (Carrasco Kind & Brunner 2013). X-ATLAS covers 7.1 deg2 observed with the XMM-Newton within the Science Demonstration…

Astrophysics of Galaxies · Physics 2017-12-06 G. Mountrichas , A. Corral , V. A. Masoura , I. Georgantopoulos , A. Ruiz , A. Georgakakis , F. J. Carrera , S. Fotopoulou

With the advent of deep, all-sky radio surveys, the need for ancillary data to make the most of the new, high-quality radio data from surveys like the Evolutionary Map of the Universe (EMU), GLEAM-X, VLASS and LoTSS is growing rapidly.…

Instrumentation and Methods for Astrophysics · Physics 2023-07-13 Kieran J. Luken , Ray P. Norris , X. Rosalind Wang , Laurence A. F. Park , Ying Guo , Miroslav D. Filipovic

New-generation radio telescopes like LOFAR are conducting extensive sky surveys, detecting millions of sources. To maximise the scientific value of these surveys, radio source components must be properly associated into physical sources…

Three-dimensional wide-field galaxy surveys are fundamental for cosmological studies. For higher redshifts (z > 1.0), where galaxies are too faint, quasars still trace the large-scale structure of the Universe. Since available telescope…

Instrumentation and Methods for Astrophysics · Physics 2022-09-21 Sándor Kunsági-Máté , Róbert Beck , István Szapudi , István Csabai

We propose a Multimodal Machine Learning method for estimating the Photometric Redshifts of quasars (PhotoRedshift-MML for short), which has long been the subject of many investigations. Our method includes two main models, i.e. the feature…

Astrophysics of Galaxies · Physics 2022-11-09 Shuxin Hong , Zhiqiang Zou , A-Li Luo , Xiao Kong , Wenyu Yang , Yanli Chen

The sparse layouts of radio interferometers result in an incomplete sampling of the sky in Fourier space which leads to artifacts in the reconstructed images. Cleaning these systematic effects is essential for the scientific use of…

Instrumentation and Methods for Astrophysics · Physics 2023-07-27 Kevin Schmidt , Felix Geyer , Stefan Fröse , Paul-Simon Blomenkamp , Marcus Brüggen , Francesco de Gasperin , Dominik Elsässer , Wolfgang Rhode

The need to analyze the available large synoptic multi-band surveys drives the development of new data-analysis methods. Photometric redshift estimation is one field of application where such new methods improved the results, substantially.…

Instrumentation and Methods for Astrophysics · Physics 2018-01-31 Antonio D'Isanto , Kai Lars Polsterer

We introduce QuasarNET, a deep convolutional neural network that performs classification and redshift estimation of astrophysical spectra with human-expert accuracy. We pose these two tasks as a \emph{feature detection} problem: presence or…

Instrumentation and Methods for Astrophysics · Physics 2018-08-31 Nicolas Busca , Christophe Balland

Data-driven approaches play a crucial role in space computing, and our paper focuses on analyzing data to learn more about celestial objects. Photometric redshift, a measure of the shift of light towards the red part of the spectrum, helps…

Instrumentation and Methods for Astrophysics · Physics 2024-11-22 Krishna Chunduri , Mithun Mahesh

Machine learning has been widely applied to clearly defined problems of astronomy and astrophysics. However, deep learning and its conceptual differences to classical machine learning have been largely overlooked in these fields. The broad…

Instrumentation and Methods for Astrophysics · Physics 2024-10-15 Nima Sedaghat , Martino Romaniello , Jonathan E. Carrick , François-Xavier Pineau

Estimating redshift is a central task in astrophysics, but its measurement is costly and time-consuming. In addition, current image-based methods are often validated on homogeneous datasets. The development and comparison of networks able…

Instrumentation and Methods for Astrophysics · Physics 2026-03-17 Alessandro Meroni , Nicolò Oreste Pinciroli Vago , Piero Fraternali

We present a machine learning search for high-redshift ($5.0 < z < 6.5$) quasars using the combined photometric data from the DESI Imaging Legacy Surveys and the WISE survey. We explore the imputation of missing values for high-redshift…

Astrophysics of Galaxies · Physics 2024-09-05 Guangping Ye , Huanian Zhang , Qingwen Wu

Quantum metrology promises high-precision measurements beyond the capability of any classical techniques, and has the potential to be integral to investigative techniques. However, all sensors must tolerate imperfections if they are to be…

Quasar photometric redshifts are essential for studying cosmology and large-scale structures. However, their complex spectral energy distributions cause significant redshift-color degeneracy, limiting the accuracy of traditional methods. To…

Astrophysics of Galaxies · Physics 2025-12-19 Jianzhen Chen , Zhijian Luo , Liping Fu , Zhu Chen , Hubing Xiao , Shaohua Zhang , Chenggang Shu

Photometric redshifts are a key tool to extract as much information as possible from planned cosmic shear experiments. In this work we aim to test the performances that can be achieved with observations in the near-infrared from space and…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Fabio Bellagamba , Massimo Meneghetti , Lauro Moscardini , Micol Bolzonella

We aim to determine the most effective approach for estimating uncertainties in quasar photo-$z$ and to evaluate the ability of different models to reconstruct the true redshift distribution under varying data quality. We use photometric…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-23 Kacper Drabicki , Szymon J. Nakoneczny , Maciej Bilicki

Point source detection at low signal-to-noise is challenging for astronomical surveys, particularly in radio interferometry images where the noise is correlated. Machine learning is a promising solution, allowing the development of…

Instrumentation and Methods for Astrophysics · Physics 2019-04-02 A. Vafaei Sadr , Etienne. E. Vos , Bruce A. Bassett , Zafiirah Hosenie , N. Oozeer , Michelle Lochner