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In this paper we further explore the properties of the HERschel Ultra Luminous Infrared Galaxy Survey (HERUS) sample of 42 local ultraluminous infrared galaxies (ULIRGs) with our recently developed Bayesian spectral energy distribution…

Astrophysics of Galaxies · Physics 2025-02-21 Charalambia Varnava , Andreas Efstathiou , Duncan Farrah , Dimitra Rigopoulou

The location of the obscuring "torus" in an active galactic nucleus (AGN) is still an unresolved issue. The line widths of X-ray fluorescence lines originated from the torus, particularly Fe K$\alpha$, carry key information on the radii of…

The availability of a robust and efficient routine for calculating light curves of a finite source magnified due to bending its light by the gravitational field of an intervening binary lens is essential for determining the characteristics…

Astrophysics · Physics 2008-11-26 M. Dominik

With new advancements in technology, it is now possible to collect data for a variety of different metrics describing tumor growth, including tumor volume, composition, and vascularity, among others. For any proposed model of tumor growth…

Quantitative Methods · Quantitative Biology 2020-09-08 Heyrim Cho , Allison L. Lewis , Kathleen M. Storey

There is growing evidence that some star-forming galaxies at z>1 are characterized by high efficiencies and specific star formation rates. In the local universe, these traits are shared by ``active'' Blue Compact Dwarf galaxies (BCDs) with…

Astrophysics · Physics 2009-11-11 L. K. Hunt , R. Maiolino

Deciding what to sense is a crucial task, made harder by dependencies and by a nonadditive utility function. We develop approximation algorithms for selecting an optimal set of measurements, under a dependency structure modeled by a…

Artificial Intelligence · Computer Science 2012-06-18 Yan Radovilsky , Solomon Eyal Shimony

We consider chance constrained optimization where it is sought to optimize a function while complying with constraints, both of which are affected by uncertainties. The high computational cost of realistic simulations strongly limits the…

Optimization and Control · Mathematics 2022-04-18 Julien Pelamatti , Rodolphe Le Riche , Céline Helbert , Christophette Blanchet-Scalliet

We present the results of a systematic, broadband X-ray spectral analysis of nearby active galactic nuclei (AGNs) with the X-ray clumpy torus model (XCLUMPY; Tanimoto et al. 2019). By adding 16 AGNs newly analyzed in this paper, we study…

High Energy Astrophysical Phenomena · Physics 2021-01-20 Shoji Ogawa , Yoshihiro Ueda , Atsushi Tanimoto , Satoshi Yamada

We studied the physical parameters of a sample comprising of all Spitzer/IRS public spectra of Seyfert galaxies in the mid-infrared (5.2-38$\mu$m range) under the active galactic nuclei (AGN) unified model. We compare the observed spectra…

Astrophysics of Galaxies · Physics 2016-09-29 Anelise Audibert , Rogério Riffel , Dinalva A. Sales , Miriani G. Pastoriza , Daniel Ruschel-Dutra

Photometric redshift estimation is becoming an increasingly important technique, although the currently existing methods present several shortcomings which hinder their application. Here it is shown that most of those drawbacks are…

Astrophysics · Physics 2011-05-05 Narciso Benitez

In the unified scheme of active galactic nuclei, a dusty torus absorbs and then reprocesses a fraction of the intrinsic luminosity which is emitted at longer wavelengths. Thus, subject to radiative transfer corrections, the fraction of the…

High Energy Astrophysical Phenomena · Physics 2017-11-08 Savithri H. Ezhikode , Poshak Gandhi , Chris Done , Martin Ward , Gulab C. Dewangan , Ranjeev Misra , Ninan Sajeeth Philip

In Bayesian optimization, Thompson sampling selects the evaluation point by sampling from the posterior distribution over the objective function maximizer. Because this sampling problem is intractable for Gaussian process (GP) surrogates,…

Machine Learning · Computer Science 2026-04-13 Donney Fan , Geoff Pleiss

In cluster analysis interest lies in probabilistically capturing partitions of individuals, items or observations into groups, such that those belonging to the same group share similar attributes or relational profiles. Bayesian posterior…

Methodology · Statistics 2017-03-23 Riccardo Rastelli , Nial Friel

Driven by the CMB temperature-redshift ($T$-$z$) relation as demanded by deconfining SU(2) Yang-Mills thermodynamics, an according cosmological model is proposed and analysed. This model -- SU(2)$_\CMB$ -- exhibits a dark sector,…

General Physics · Physics 2018-12-13 Steffen Hahn , Ralf Hofmann , Daniel Kramer

We develop a new methodology for model-based clustering. Optimizing the log-likelihood provides a principled statistical framework for clustering, with solutions found via the EM algorithm. However, because the log-likelihood is nonconvex,…

Methodology · Statistics 2026-05-06 Gonzalo Mena

Infinite nuclear matter provides valuable insights into the behavior of nuclear systems and aids our understanding of atomic nuclei and large-scale stellar objects such as neutron stars. However, partly due to the large basis needed to…

Nuclear Theory · Physics 2024-12-31 Julie Butler , Morten Hjorth-Jensen , Gustav R. Jansen

We study the extinction efficiencies as well as scattering properties of particles of different porosity. Calculations are performed for porous pseudospheres with small size (Rayleigh) inclusions using the discrete dipole approximation.…

Astrophysics · Physics 2009-11-13 N. V. Voshchinnikov , G. Videen , Th. Henning

Models for structure formation attempt to predict the power spectrum of density perturbations in the present universe from the initial power spectrum and the nature of dark matter. Observational constraints on the power spectrum at…

Astrophysics · Physics 2007-05-23 K. Subramanian , T. Padmanabhan

We propose a new method to constrain the size of the dusty torus in broad-line active galactic nuclei (AGNs) using optical and mid-infrared (MIR) ensemble structure functions (SFs). Because of the geometric dilution of the torus, the MIR…

Astrophysics of Galaxies · Physics 2023-06-28 Junyao Li , Yue Shen
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