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Related papers: Fast spectral line calculations with the escape pr…

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We present a new method, the Coupled Escape Probability (CEP), for exact calculation of line emission from multi-level systems, solving only algebraic equations for the level populations. The CEP formulation of the classical two-level…

Astrophysics · Physics 2009-11-13 Moshe Elitzur , Andres Asensio Ramos

Accurate modelling of the effective point spread function (ePSF) is essential for high-precision photometry and astrometry, particularly in undersampled imaging regimes. In this work, we build on a well-established ePSF modelling framework…

Instrumentation and Methods for Astrophysics · Physics 2025-12-19 Emma Godden , Katherine M. Blundell

In astrophysics, atomic transition line opacity is a primary source of uncertainty in theoretical calculations of radiative transfer. Much of this uncertainty is dominated by the inability to resolve the lines in frequency, leading to the…

High Energy Astrophysical Phenomena · Physics 2026-04-14 Jonathan Morag

The fitting of spectral lines is a common step in the analysis of line observations and simulations. However, the observational noise, the presence of multiple velocity components, and potentially large data sets make it a non-trivial task.…

Astrophysics of Galaxies · Physics 2024-03-08 Mika Juvela , Devika Tharakkal

In this paper we discuss two approximate methods previously suggested for modeling hyperfine spectral line emission for molecules whose collisional transitions rates between hyperfine levels are unknown. Hyperfine structure is seen in the…

Astrophysics of Galaxies · Physics 2015-05-18 Eric Keto , George Rybicki

We present a modular, extensible likelihood framework for spectroscopic inference based on synthetic model spectra. The subtraction of an imperfect model from a continuously sampled spectrum introduces covariance between adjacent datapoints…

Solar and Stellar Astrophysics · Physics 2015-10-21 Ian Czekala , Sean M. Andrews , Kaisey S. Mandel , David W. Hogg , Gregory M. Green

Eclipsing binaries provide one of the most direct mechanisms for measuring stellar properties such as mass and radius, but historically, determining these properties has been non-trivial and computationally prohibitive. As such, only a…

Parameter-efficient finetuning (PEFT) has become ubiquitous to adapt foundation models to downstream task requirements while retaining their generalization ability. However, the amount of additionally introduced parameters and compute for…

Machine Learning · Computer Science 2024-10-14 Massimo Bini , Karsten Roth , Zeynep Akata , Anna Khoreva

Exact inference in the linear regression model with spike and slab priors is often intractable. Expectation propagation (EP) can be used for approximate inference. However, the regular sequential form of EP (R-EP) may fail to converge in…

Machine Learning · Statistics 2011-12-13 José Miguel Hernández-Lobato , Daniel Hernández-Lobato

A new, iterative algorithm is presented to calculate the Embedded Element Pattern (EEP) tranformation from a set of patterns computed for a uniform antenna port loading (scaled identinty matrix) to a set of those computed for a non-uniform…

Instrumentation and Methods for Astrophysics · Physics 2026-01-23 Georgios Kyriakou

We present a multi-fidelity method for uncertainty quantification of parameter estimates in complex systems, leveraging generative models trained to sample the target conditional distribution. In the Bayesian inference setting, traditional…

Machine Learning · Computer Science 2025-04-03 Caroline Tatsuoka , Minglei Yang , Dongbin Xiu , Guannan Zhang

In today's era, Neural Networks (NN) are applied in various scientific fields such as robotics, medicine, engineering, etc. However, the predictions of neural networks themselves contain a degree of uncertainty that must always be taken…

Machine Learning · Computer Science 2025-04-01 E. V. Aretos , D. G. Sotiropoulos

Electromagnetic radiation plays a crucial role in various physical and chemical processes. Hence, almost all astrophysical simulations require some form of radiative transfer model. Despite many innovations in radiative transfer algorithms…

Instrumentation and Methods for Astrophysics · Physics 2022-12-07 Frederik De Ceuster , Thomas Ceulemans , Jon Cockayne , Leen Decin , Jeremy Yates

Electron beam probe (EBP) is a new principle detector, which makes use of a low-intensity and low-energy electron beam to measure the transverse profile, bunch shape, beam neutralization and beam wake field of an intense beam with small…

A fundamental challenge for wide-field imaging surveys is obtaining follow-up spectroscopic observations: there are > $10^9$ photometrically cataloged sources, yet modern spectroscopic surveys are limited to ~few x $10^6$ targets. As we…

Solar and Stellar Astrophysics · Physics 2015-06-23 A. A. Miller , J. S. Bloom , J. W. Richards , Y. S. Lee , D. L. Starr , N. R. Butler , S. Tokarz , N. Smith , J. A. Eisner

Differential equations are pivotal in modeling and understanding the dynamics of various systems, offering insights into their future states through parameter estimation fitted to time series data. In fields such as economy, politics, and…

Machine Learning · Statistics 2024-04-24 Hyeontae Jo , Sung Woong Cho , Hyung Ju Hwang

This paper considers an alternative method for fitting CARR models using combined estimating functions (CEF) by showing its usefulness in applications in economics and quantitative finance. The associated information matrix for…

Applications · Statistics 2017-02-09 Kok-Haur Ng , Shelton Peiris , Jennifer So-kuen-Chan , David Allen , Kooi-Huat Ng

Mixed-effects regression models represent a useful subclass of regression models for grouped data; the introduction of random effects allows for the correlation between observations within each group to be conveniently captured when…

Methodology · Statistics 2024-09-25 Jackson Zhou , John T. Ormerod , Clara Grazian

Over the years data assimilation methods have been developed to obtain estimations of uncertain model parameters by taking into account a few observations of a model state. The most reliable methods of MCMC are computationally expensive.…

Applications · Statistics 2018-11-14 Sangeetika Ruchi , Svetlana Dubinkina

Quantifying and reducing uncertainty in Earth system model parameterizations is essential to improving their reliability in decision-making. Forward uncertainty propagation is used to derive parameter sensitivity but requires physically…

Atmospheric and Oceanic Physics · Physics 2026-04-22 Ethan YoungIn Shin , Baris Kale , Michael F. Howland
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