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The inference of astrophysical and cosmological properties from the Lyman-$\alpha$ forest conventionally relies on summary statistics of the transmission field that carry useful but limited information. We present a deep learning framework…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-11 Parth Nayak , Michael Walther , Daniel Gruen , Sreyas Adiraju

Blazars are active galactic nuclei with relativistic jets pointed almost directly at Earth. Blazars are characterized by strong, apparently stochastic flux variability at virtually all observed wavelengths and timescales, from minutes to…

High Energy Astrophysical Phenomena · Physics 2023-02-16 Aryeh Brill

We perform two distinct spatio-spectral reconstructions of the gamma-ray sky in the range of 0.56-316 GeV based on Fermi Large Area Telescope (LAT) data. Both describe the sky brightness to be composed of a diffuse-emission and a…

High Energy Astrophysical Phenomena · Physics 2023-12-13 Lukas I. Platz , Jakob Knollmüller , Philipp Arras , Philipp Frank , Martin Reinecke , Dominik Jüstel , Torsten A. Enßlin

Recent observations of the diffuse Galactic \gr emission (DGE) by the {\it Fermi} Large Area Telescope ({\it Fermi}-LAT) have shown significant deviations, above a few GeV until about 100 GeV, from DGE models that use the GALPROP code for…

High Energy Astrophysical Phenomena · Physics 2015-06-17 Heinrich J. Voelk , Evgeny G. Berezhko

The multiscale variance stabilization Transform (MSVST) has recently been proposed for Poisson data denoising. This procedure, which is nonparametric, is based on thresholding wavelet coefficients. We present in this paper an extension of…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 J. -L. Starck , J. M. Fadili , S. Digel , B. Zhang , J. Chiang

In our previous work in Xiao et al. (2019), we suggested that 6 superluminal sources could be gamma-ray candidates, and in fact 5 of them have been confirmed in the fourth Fermi-LAT source catalogue (4FGL). In this work, based on the 4FGL,…

High Energy Astrophysical Phenomena · Physics 2020-07-15 Hubing Xiao , Junhui Fan , Riccardo Rando , Jingtian Zhu , Liangjun Hu

We present an extension of reverse engineered Kohn-Sham potentials from a density matrix renormalization group calculation towards the construction of a density functional theory functional via deep learning. Instead of applying machine…

Disordered Systems and Neural Networks · Physics 2021-05-05 Peter Schmitteckert

Deep learning applications are drastically progressing in seismic processing and interpretation tasks. However, the majority of approaches subsample data volumes and restrict model sizes to minimise computational requirements. Subsampling…

Geophysics · Physics 2021-02-26 Claire Birnie , Haithem Jarraya , Fredrik Hansteen

We show the existence of a statistically significant, robust detection of a gamma-ray source in the Milky Way Galactic Center that is consistent with a spatially extended signal using about 4 years of Fermi-LAT data. The gamma-ray flux is…

High Energy Astrophysical Phenomena · Physics 2013-05-23 Kevork N. Abazajian , Manoj Kaplinghat

This paper studies the decentralized learning of tree-structured Gaussian graphical models (GGMs) from noisy data. In decentralized learning, data set is distributed across different machines (sensors), and GGMs are widely used to model…

Machine Learning · Computer Science 2021-09-23 Akram Hussain

To deploy and operate deep neural models in production, the quality of their predictions, which might be contaminated benignly or manipulated maliciously by input distributional deviations, must be monitored and assessed. Specifically, we…

Computer Vision and Pattern Recognition · Computer Science 2023-06-09 Guy Bar-Shalom , Yonatan Geifman , Ran El-Yaniv

We search for dark matter (DM) annihilating subhalos of the Milky Way halo among the Fermi Large Area Telescope (LAT) unassociated sources. We construct, for the first time, a statistical model of the unassociated sources at latitudes above…

High Energy Astrophysical Phenomena · Physics 2025-03-20 Aurelio Amerio , Dmitry Malyshev , Bryan Zaldivar , Viviana Gammaldi , Miguel Ángel Sánchez-Conde

Dwarf spheroidal galaxies (dSphs) are promising targets for the indirect detection of dark matter through gamma-ray emission due to their proximity, lack of astrophysical backgrounds and high dark matter density. They are often used to…

High Energy Physics - Phenomenology · Physics 2016-06-01 Matthew G. Baring , Tathagata Ghosh , Farinaldo S. Queiroz , Kuver Sinha

With the advent of next-generation surveys and the expectation of discovering huge numbers of strong gravitational lens systems, much effort is being invested into developing automated procedures for handling the data. The several orders of…

Astrophysics of Galaxies · Physics 2021-02-17 Jacob Maresca , Simon Dye , Nan Li

Previously, we have shown in Li et al. (2018) that very weak $\gamma$-ray excesses ($\sim 2\sigma$) appear in some Milky Way dwarf spheroidal galaxies (dSphs, including candidates) and the combination analysis of 12 nearby dSphs yields a…

High Energy Astrophysical Phenomena · Physics 2021-11-10 Shang Li , Yun-Feng Liang , Yi-Zhong Fan

We report the detection of two new gamma-ray sources in the Fermi-LAT sky (Pass 8) at energies higher than 20 GeV, and confirmed at lower energies, using a source detection tool based on the Minimum Spanning Tree algorithm. One of these…

High Energy Astrophysical Phenomena · Physics 2017-01-25 R. Campana , A. Maselli , E. Bernieri , E. Massaro

Unassociated Fermi-LAT sources provide a population with discovery potential. We discuss efforts to find new source associations for this population, and summarize the successes to date. We discuss how the measured gamma-ray properties of…

High Energy Astrophysical Phenomena · Physics 2012-06-13 Elizabeth C. Ferrara , Roopesh Ojha , Maria Elena Monzani , Nicola Omodei

We present the analysis of Fermi Large Area Telecope (LAT) data of the gamma-ray emission in the vicinity of a radio supernova remnant (SNR), G045.7$-$00.4. To study the origin of the gamma-ray emission, we also make use of the CO survey…

High Energy Astrophysical Phenomena · Physics 2022-07-12 Hai-Ming Zhang , Ruo-Yu Liu , Yang Su , Hui Zhu , Shao-Qiang Xi , Xiang-Yu Wang

Observations using the Fermi Large Area Telescope (Fermi-LAT) have found a significant gamma-ray excess surrounding the center of the Milky Way (GC). One possible interpretation of this excess invokes gamma-ray emission from an undiscovered…

High Energy Astrophysical Phenomena · Physics 2016-03-23 Tim Linden

With almost 15 years of data taken by the Large Area Telescope (LAT) onboard the Fermi satellite we discovered an extended source of GeV emission in the region of the very-high-energy (TeV) source 1LHAASO J1945+2424. This TeV source is more…

High Energy Astrophysical Phenomena · Physics 2023-12-05 Miguel Araya , J. A. Álvarez-Quesada