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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

We present Mantis Shrimp, a multi-survey deep learning model for photometric redshift estimation that fuses ultra-violet (GALEX), optical (PanSTARRS), and infrared (UnWISE) imagery. Machine learning is now an established approach for…

Instrumentation and Methods for Astrophysics · Physics 2025-08-01 Andrew Engel , Nell Byler , Adam Tsou , Gautham Narayan , Emmanuel Bonilla , Ian Smith

We have computed obscured AGN redshifts using the XZ method, adopting a broad treatment in which we employed a wide-ranging data set and worked primarily at the XZ counts sensitivity threshold, culminating with a redshift catalog containing…

High Energy Astrophysical Phenomena · Physics 2022-09-07 Dominic Sicilian , Francesca Civano , Nico Cappelluti , Johannes Buchner , Alessandro Peca

Gamma-ray bursts (GRBs) detected at high redshift can be used to trace the cosmic expansion history. However, the calibration of their luminosity distances is not an easy task in comparison to Type Ia Supernovae (SNeIa). To calibrate these…

Cosmology and Nongalactic Astrophysics · Physics 2022-04-20 Celia Escamilla-Rivera , Maryi Carvajal , Cristian Zamora , Martin Hendry

We have used FMOS on Subaru to obtain near-infrared spectroscopy of 123 far-infrared selected galaxies in COSMOS and obtain the key rest-frame optical emission lines. This is the largest sample of infrared galaxies with near-infrared…

Differentiating between active galactic nuclei (AGN) activity and star formation in z ~ 2 galaxies is difficult because traditional methods, such as line ratio diagnostics, change with redshift while multi-wavelength methods (X-ray, radio,…

We investigate the fraction of z ~ 0.3 Lyman alpha emitting galaxies (LAEs) which host active galactic nucleus activity, which is typically from 1 - 5% at 2 < z < 6. Using optical spectroscopy of 23 LAEs at 0.2 < z < 0.45 selected with…

Cosmology and Nongalactic Astrophysics · Physics 2009-09-24 Steven L. Finkelstein , Seth H. Cohen , Sangeeta Malhotra , James E. Rhoads , Casey Papovich , Zhenya Zheng , Junxian Wang

To investigate GRBs in depth, it is crucial to develop an effective method for identifying GRBs accurately. Current criteria, e.g., onboard blind search, ground blind search, and target search, are limited by manually set thresholds and…

High Energy Astrophysical Phenomena · Physics 2024-12-20 Peng Zhang , Bing Li , RenZhou Gui , Shaolin Xiong , Ze-Cheng Zou , Xianggao Wang , Xiaobo Li , Ce Cai , Yi Zhao , Yanqiu Zhang , Wangchen Xue , Chao Zheng , Hongyu Zhao

Large sky spectroscopic surveys have reached the scale of photometric surveys in terms of sample sizes and data complexity. These huge datasets require efficient, accurate, and flexible automated tools for data analysis and science…

Reverberation mapping is one of the main techniques used to study active galactic nuclei (AGN) accretion disks. Traditional continuum reverberation mapping uses short lags between variability in different wavelength AGN light curves on the…

Astrophysics of Galaxies · Physics 2026-01-15 Amy Secunda , Sebastian Wagner-Carena , Helen Qu , Shirley Ho

The quest to uncover periodic patterns within the $\gamma$-ray emissions of jetted active galactic nuclei (AGN) has recently emerged as a focal point in astrophysics. One of the primary challenges has been the necessity for prolonged…

High Energy Astrophysical Phenomena · Physics 2025-10-23 P. Peñil , A. Domínguez , S. Buson , M. Ajello , S. Adhikari , A. Rico

The classifications of Fermi-LAT unassociated sources are studied using multiple machine learning (ML) methods. The update data from 4FGL-DR3 are divided into high Galactic latitude (HGL, Galactic latitude $|b|>10^\circ$) and low Galactic…

High Energy Astrophysical Phenomena · Physics 2023-11-08 K. R. Zhu , J. M. Chen , Y. G. Zheng , L. Zhang

Machine learning models can greatly improve the search for strong gravitational lenses in imaging surveys by reducing the amount of human inspection required. In this work, we test the performance of supervised, semi-supervised, and…

Astrophysics of Galaxies · Physics 2023-08-17 Keerthi Vasan G. C. , Stephen Sheng , Tucker Jones , Chi Po Choi , James Sharpnack

Radio-loud active galactic nuclei (AGN) are expected to contribute substantially to both the intensity and anisotropy of the isotropic gamma-ray background (IGRB). In turn, the measured properties of the IGRB can be used to constrain the…

High Energy Astrophysical Phenomena · Physics 2014-12-03 Mattia Di Mauro , Alessandro Cuoco , Fiorenza Donato , Jennifer M. Siegal-Gaskins

This is a follow-up sensitivity study on r-mode gravitational wave signals from newborn neutron stars illustrating the applicability of machine learning algorithms for the detection of long-lived gravitational-wave transients. In this…

Instrumentation and Methods for Astrophysics · Physics 2019-01-23 Antonis Mytidis , Athanasios Aris Panagopoulos , Orestis P. Panagopoulos , Andrew Miller , Bernard Whiting

We used data from the Hobby-Eberly Telescope Dark Energy Experiment (HETDEX) to study the incidence of AGN in continuum-selected galaxies at $z\sim3$. From optical and infrared imaging in the 24 deg$^{2}$ Spitzer HETDEX Exploratory Large…

Building on the first paper in this series (Duncan et al. 2018), we present a study investigating the performance of Gaussian process photometric redshift (photo-z) estimates for galaxies and active galactic nuclei detected in deep radio…

Astrophysics of Galaxies · Physics 2018-05-24 Kenneth J Duncan , Matt J. Jarvis , Michael J. I. Brown , Huub J. A. Rottgering

The most popular method of the broad-line region size estimation in active galactic nuclei (AGN) is the reverberation mapping based on measuring the time delay between the continuum flux and the flux in the emission lines. In our work, we…

Instrumentation and Methods for Astrophysics · Physics 2020-01-29 Eugene Malygin , Roman Uklein , Elena Shablovinskaya , Aleksander Perepelitsyn , Aleksandra Grokhovskaya

A catalogue of 14453 radio-loud AGN with 1.4 GHz fluxes above 3.5 mJy in the redshift range 0.4<z<0.8, has been constructed from the cross-correlation of the NVSS and FIRST radio surveys with the MegaZ-LRG catalogue of luminous red galaxies…

Astrophysics · Physics 2010-11-30 E. Donoso , P. N. Best , G. Kauffmann

The sensitivity of the Large Area Telescope (LAT) aboard the Fermi Gamma-ray Space Telescope allows detection of thousands of new gamma-ray sources and detailed characterization of the spectra and variability of bright sources.…

Instrumentation and Methods for Astrophysics · Physics 2015-03-18 Matthew Kerr