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Related papers: Maximum-Entropy analysis of EGRET data

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The Principle of Maximum Entropy is a rigorous technique for estimating an unknown distribution given partial information while simultaneously minimizing bias. However, an important requirement for applying the principle is that the…

Information Theory · Computer Science 2026-02-03 Kenneth Bogert , Matthew Kothe

Radio polarisation images of the jets of Active Galactic Nuclei (AGN) can provide a deep insight into the launching and collimation mechanisms of relativistic jets. However, even at VLBI scales, resolution is often a limiting factor in the…

Astrophysics of Galaxies · Physics 2016-09-07 Colm P. Coughlan , Denise C. Gabuzda

We describe a method to computationally estimate the probability density function of a univariate random variable by applying the maximum entropy principle with some local conditions given by Gaussian functions. The estimation errors and…

Statistics Theory · Mathematics 2012-06-21 Mihail-Ioan Pop

With the aim of testing recent claims for a particularly strong correlation between ultra-high energy cosmic rays (UHECRs), observed with the AGASA and the Yakutsk experiments, and a sample of BL Lacertae (BL Lacs), we here conduct a blind…

Astrophysics · Physics 2009-11-10 Diego F. Torres , Stephen Reucroft , Olaf Reimer , Luis A. Anchordoqui

Multiple-channel detection is considered in the context of a sensor network where raw data are shared only by nodes that have a common edge in the network graph. Established multiple-channel detectors, such as those based on generalized…

Applications · Statistics 2016-11-15 Douglas Cochran , Stephen D. Howard , Bill Moran , Harry A. Schmitt

We investigate the dependence of the maximum entropy method (MEM) reconstruction performance on the default model. The maximum entropy method is a reconstruction technique that utilizes prior information, referred to as the default model,…

Statistical Mechanics · Physics 2025-10-06 Masaru Hitomi , Masayuki Ohzeki

Ground based Cherenkov telescope systems measure astrophysical gamma-ray emission against a background of cosmic-ray induced air showers. The subtraction of this background is a major challenge for the extraction of spectra and morphology…

Astrophysics · Physics 2008-11-26 D. Berge , S. Funk , J. Hinton

We use the recent measurement of the isotropic $\gamma$-ray background (IGRB) by Fermi LAT and analysis of the contribution of unresolved point $\gamma$-ray sources to IGRB to build constraints on the models of ultra-high cosmic rays…

High Energy Astrophysical Phenomena · Physics 2016-11-23 Oleg Kalashev

The Expectation Maximization (EM) algorithm is widely used as an iterative modification to maximum likelihood estimation when the data is incomplete. We focus on a semi-supervised case to learn the model from labeled and unlabeled samples.…

Machine Learning · Computer Science 2023-01-26 Erixhen Sula , Lizhong Zheng

Moment-closure methods are popular tools to simplify the mathematical analysis of stochastic models defined on networks, in which high dimensional joint distributions are approximated (often by some heuristic argument) as functions of lower…

Data Analysis, Statistics and Probability · Physics 2011-05-25 Tim Rogers

We propose a new method to search for heavy nuclei sources, on top of background, in the Ultra-High Energy Cosmic Ray data. We apply this method to the 69 events recently published by the Pierre Auger Collaboration and find a tail of events…

High Energy Astrophysical Phenomena · Physics 2015-03-17 G. Giacinti , D. V. Semikoz

We describe an X-ray source detection method entirely based on the maximum likelihood analysis, in application to observations with the ART-XC telescope onboard the Spectrum Roentgen Gamma observatory. The method optimally combines the data…

High Energy Astrophysical Phenomena · Physics 2024-04-03 A. Semena , A. Vikhlinin , I. Mereminskiy , A. Lutovinov , A. Tkachenko , I. Lapshov , R. Burenin

Semi-continuous data comes from a distribution that is a mixture of the point mass at zero and a continuous distribution with support on the positive real line. A clear example is the daily rainfall data. In this paper, we present a novel…

Methodology · Statistics 2021-06-17 Sai K. Popuri , Nagaraj K. Neerchal , Amita Mehta , Ahmad Mousavi

We will present a summary of the observations of blazars by the Energetic Gamma Ray Experiment Telescope (EGRET) on the Compton Gamma Ray Observatory (CGRO). EGRET has detected high energy gamma-ray emission at energies greater than 100 MeV…

Astrophysics · Physics 2016-01-27 R. Mukherjee

Neutrino telescopes are moving steadily toward the goal of detecting astrophysical neutrinos from the most powerful galactic and extragalactic sources. Here we describe analysis methods to search for high energy point-like neutrino sources…

Astrophysics · Physics 2009-06-23 Jim Braun , Jon Dumm , Francesco De Palma , Chad Finley , Albrecht Karle , Teresa Montaruli

The ultra-high contrast capability required to form images of other solar systems is arguably the highest-profile challenge in astronomy today. The current high-contrast imaging efforts all require background subtraction to separate the…

Instrumentation and Methods for Astrophysics · Physics 2015-07-29 Richard A. Frazin

We present the results of a search for cosmic ray point sources at energies above 10^19 eV in the HiRes stereo data set. The analysis is based on a maximum likelihood ratio test using the probability density function for each event rather…

Astrophysics · Physics 2019-08-14 Stefan Westerhoff , Chad B. Finley

The maximum-likelihood method for quantum estimation is reviewed and applied to the reconstruction of density matrix of spin and radiation as well as to the determination of several parameters of interest in quantum optics.

Quantum Physics · Physics 2009-11-07 M. G. A. Paris , G. M. D'Ariano , M. F. Sacchi

One way to understand the nonthermal history of the universe is by establishing the origins of the unresolved and truly diffuse extragalactic gamma rays. Dim blazars and radio/gamma galaxies certainly make an important contribution to the…

Astrophysics · Physics 2009-06-23 Charles D. Dermer
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