English
Related papers

Related papers: Dynamical Modelling of Hot Stellar Systems

200 papers

Nonlinear systems with model uncertainty are often described by stochastic differential equations. Some techniques from random dynamical systems are discussed. They are relevant to better understanding of solution processes of stochastic…

Dynamical Systems · Mathematics 2008-11-25 Jinqiao Duan

In this work we try to understand the late time acceleration of the universe by assuming some modification in the geometry of the space and using dynamical system analysis. This technique allows to understand the behavior of the universe…

General Relativity and Quantum Cosmology · Physics 2021-11-18 Parth Shah , Gauranga C. Samanta

In this paper, we have presented a power law cosmological model and its dynamical system analysis in $f(T,\phi)$ gravity, where $T$ is the torsion scalar and $\phi$ is the canonical scalar field. The two well-motivated forms of the…

General Relativity and Quantum Cosmology · Physics 2025-01-10 S. A. Kadam , Ananya Sahu , S. K. Tripathy , B. Mishra

In this paper we consider a class of nonparametric estimators of a distribution function F, with compact support, based on the theory of IFSs. The estimator of F is tought as the fixed point of a contractive operator T defined in terms of a…

Statistics Theory · Mathematics 2007-06-13 Stefano M. Iacus , Davide La Torre

When predicting scalar responses in the situation where the explanatory variables are functions, it is sometimes the case that some functional variables are related to responses linearly while other variables have more complicated…

Methodology · Statistics 2012-11-29 Heng Lian

Interferometric observations of stars in late stages of stellar evolution and the impact of VLTI observations are discussed. Special attention is paid to the spectral information that can be derived from these observations and on the…

Astrophysics · Physics 2015-06-24 T. Bloecker , K. -H. Hofmann , G. Weigelt

The structure, kinematics and dynamics of the Galactic stellar halo are reviewed including evidence of substructure in the spatial distribution and kinematics of halo stars. Implications for galaxy formation theory are subsequently…

Astrophysics · Physics 2009-10-31 Jesper Sommer-Larsen

We present a numerical method for learning the dynamics of slow components of unknown multiscale stochastic dynamical systems. While the governing equations of the systems are unknown, bursts of observation data of the slow variables are…

Machine Learning · Computer Science 2024-08-28 Yuan Chen , Dongbin Xiu

We estimate the halo mass function (HMF) by applying the excursion set approach to the non-linear cosmic density field. Thereby, we account for the non-Gaussianity of today's density distribution and constrain the HMF independent of the…

Cosmology and Nongalactic Astrophysics · Physics 2020-02-25 Laila Linke , Johannes Schwinn , Matthias Bartelmann

We present a new tool for the photometric estimate of stellar masses in distant galaxies. The observed SEDs are fitted by combining single stellar populations, with different SFRs and amounts of dust extinction. This approach gives us the…

The aim of the present paper is to quantify the dependence of the estimates of luminosities and stellar mass of early-type galaxies on the different models and model parameters which can be used to analyze the observational data. The paper…

Astrophysics · Physics 2009-11-13 Marcella Longhetti , Paolo Saracco

We consider the problem of statistical inference for the effective dynamics of multiscale diffusion processes with (at least) two widely separated characteristic time scales. More precisely, we seek to determine parameters in the effective…

Statistics Theory · Mathematics 2013-05-30 Sebastian Krumscheid , Grigorios A. Pavliotis , Serafim Kalliadasis

The recent asteroseismic data from the CoRoT and Kepler missions have provided an entirely new basis for investigating stellar properties. This has led to a rapid development in techniques for analysing such data, although it is probably…

Solar and Stellar Astrophysics · Physics 2015-06-12 J. Christensen-Dalsgaard

A novel approach to the problem of partial state estimation of nonlinear systems is proposed. The main idea is to translate the state estimation problem into one of estimation of constant, unknown parameters related to the systems initial…

Systems and Control · Computer Science 2016-04-08 Ortega Romeo , Bobtsov Alexey , Pyrkin Anton , Aranovskiy Stanislav

Current burning issues in stellar physics, for both hot and cool stars, concern their magnetism. In hot stars, stable magnetic fields of fossil origin impact their stellar structure and circumstellar environment, with a likely major role in…

Solar and Stellar Astrophysics · Physics 2019-03-18 C. Neiner , J. Morin , J. -C. Bouret , L. Fossati

The novel proposal to invoke the split of the Ricci scalar into bulk and boundary terms in the gravitational action, opens up a new avenue of investigation into stellar dynamics. The Lagrangian contains functional forms of the bulk term…

General Relativity and Quantum Cosmology · Physics 2026-05-14 Sudan Hansraj , Christian G. Boehmer , Ndumiso Buthelezi

Since the early 1970s, stellar population modelling has been one of the basic tools for understanding the physics of unresolved systems from observation of their integrated light. Models allow us to relate the integrated spectra (or…

Instrumentation and Methods for Astrophysics · Physics 2013-12-03 Miguel Cerviño

I review recent results from numerical simulations on the structure and dynamics of the ISM, and attempt to put together a coherent dynamical scenario. In particular, I discuss results on 1) the spatial distribution of the gas components,…

Astrophysics · Physics 2007-05-23 Enrique Vazquez-Semadeni

Non-linear state estimation and some related topics, like parametric estimation, fault diagnosis, and perturbation attenuation, are tackled here via a new methodology in numerical differentiation. The corresponding basic system theoretic…

Computational Engineering, Finance, and Science · Computer Science 2008-11-06 Michel Fliess , Cédric Join , Hebertt Sira-Ramirez

Analytic distribution functions (DFs) for the Galactic disc are discussed. The DFs depend on action variables and their predictions for observable quantities are explored under the assumption that the motion perpendicular to the Galactic…

Astrophysics of Galaxies · Physics 2015-05-14 James Binney
‹ Prev 1 3 4 5 6 7 10 Next ›