English
Related papers

Related papers: Radiative transfer on hierarchial grids

200 papers

We present high resolution transmission spectra, calculated directly from a 3D radiative-hydrodynamics simulation that includes kinetic cloud formation, for HD209458b. We find that the high opacity of our vertically extensive cloud deck,…

Earth and Planetary Astrophysics · Physics 2021-06-04 S. Lines , J. Manners , N. J. Mayne , J. Goyal , A. L. Carter , I. A. Boutle , E. K. H. Lee , Ch. Helling , B. Drummond , D. M. Acreman , D. K. Sing

Convolutional Gridding is a technique (algorithm) extensively used in Radio Interferometric Image Synthesis for fast inversion of functions sampled with irregular intervals on the Fourier plane. In this thesis, we propose some modifications…

Instrumentation and Methods for Astrophysics · Physics 2021-11-09 Daniel Muscat

Stable Diffusion Models (SDMs) have shown remarkable proficiency in image synthesis. However, their broad application is impeded by their large model sizes and intensive computational requirements, which typically require expensive cloud…

Computer Vision and Pattern Recognition · Computer Science 2024-10-31 Chenqian Yan , Songwei Liu , Hongjian Liu , Xurui Peng , Xiaojian Wang , Fangmin Chen , Lean Fu , Xing Mei

This paper presents a simple analytical framework for the dynamic response of cirrus to a local radiative flux convergence, expressible in terms of three independent modes of cloud evolution. Horizontally narrow and tenuous clouds within a…

Atmospheric and Oceanic Physics · Physics 2015-06-04 C. T. Schmidt , T. J. Garrett

Context: Dynamical studies of irradiated circumstellar disks require an accurate treatment of radiation transport to, for example, properly determine cooling and fragmentation properties. The radiation transport algorithm should be as fast…

Solar and Stellar Astrophysics · Physics 2013-06-20 Rolf Kuiper , Ralf S. Klessen

The challenge to fully exploit the potential of existing and upcoming scientific instruments like large single-dish radio telescopes is to process the collected massive data effectively and efficiently. As a "quasi 2D stencil computation"…

Distributed, Parallel, and Cluster Computing · Computer Science 2022-07-12 Hao Wang , Ce Yu , Jian Xiao , Shanjiang Tang , Min Long , Ming Zhu

To improve the computational efficiencies of the real-space orbital-free density functional theory, this work develops a new single-grid solver by directly providing the closed-form solution to the inner iteration and using an improved…

Computational Physics · Physics 2023-05-16 Ling-Ze Bu , Wei Wang

We present a novel Lyman alpha (Ly$\alpha$) radiative transfer code, SEURAT, where line scatterings are solved adaptively with the resolution of the smoothed particle hydrodynamics (SPH). The radiative transfer method implemented in SEURAT…

Instrumentation and Methods for Astrophysics · Physics 2018-01-30 Makito Abe , Hiroyuki Suzuki , Kenji Hasegawa , Benoit Semelin , Hidenobu Yajima , Masayuki Umemura

We present LVG and non-local radiative transfer calculations involving the rotational and hyperfine structure of the spectrum of N$_2$H$^+$ with collisional rate coefficients recently derived by us. The goal of this study is to check the…

Astrophysics · Physics 2008-11-26 F. Daniel , J. Cernicharo , M. -L. Dubernet

We present a novel ray acceleration structure for radiative transfer outside of local thermodynamic equilibrium (non-LTE), leveraging techniques from computer graphics to improve computational efficiency. By applying mipmapping (local…

Instrumentation and Methods for Astrophysics · Physics 2025-11-12 Christopher M. J. Osborne

Fitting spectral distributions of total fluxes or image intensities are two standard methods for estimating the masses of starless cores and protostellar envelopes. These mass estimates, which are the main source and basis of our knowledge…

Instrumentation and Methods for Astrophysics · Physics 2016-09-28 Alexander Men'shchikov

The formalism of the scattering matrix is applied to describe the transmission properties of multilayered structures with deep variations of the refractive index and arbitrary arrangements of the layers. We show that there is an exact…

Optics · Physics 2011-09-22 Victor Grigoriev , Fabio Biancalana

Implicit solvers present strong limitations when used on supercomputing facilities and in particular for adaptive mesh-refinement codes. We present a new method for implicit adaptive time-stepping on adaptive mesh refinement-grids. We…

Instrumentation and Methods for Astrophysics · Physics 2014-03-05 Benoit Commercon , Vincent Debout , Romain Teyssier

The interstellar dust content in galaxies can be traced in extinction at optical wavelengths, or in emission in the far-infrared. Several studies have found that radiative transfer models that successfully explain the optical extinction in…

Astrophysics of Galaxies · Physics 2015-06-23 W. Saftly , M. Baes , G. De Geyter , P. Camps , F. Renaud , J. Guedes , I. De Looze

We extract a core principle underlying seemingly different fundamental distributed settings, showing sparsity awareness may induce faster algorithms for problems in these settings. To leverage this, we establish a new framework by…

Distributed, Parallel, and Cluster Computing · Computer Science 2021-12-01 Keren Censor-Hillel , Dean Leitersdorf , Volodymyr Polosukhin

Scattered data fitting is a frequently encountered problem for reconstructing an unknown function from given scattered data. Radial basis function (RBF) methods have proven to be highly useful to deal with this problem. We describe two…

Numerical Analysis · Mathematics 2021-12-21 Lingxia Cui , Hua Xiang

While diffusion-based image restoration (IR) methods have achieved remarkable success, they are still limited by the low inference speed attributed to the necessity of executing hundreds or even thousands of sampling steps. Existing…

Computer Vision and Pattern Recognition · Computer Science 2024-11-26 Zongsheng Yue , Jianyi Wang , Chen Change Loy

Super resolution offers a way to harness medium even lowresolution but historically valuable remote sensing image archives. Generative models, especially diffusion models, have recently been applied to remote sensing super resolution…

Computer Vision and Pattern Recognition · Computer Science 2025-10-28 Songxi Yang , Tang Sui , Qunying Huang

The increasing size of solar datasets demands highly efficient and robust analysis methods. This paper presents an approach that can increase the computational efficiency of differential emission measure (DEM) inversions by an order of…

Solar and Stellar Astrophysics · Physics 2019-10-09 James Pickering , Huw Morgan

Measured properties of young stellar objects (YSOs) are key tools for research into pre-main-sequence stellar evolution. YSO properties are commonly measured by comparing observed radiation to existing grids of template YSO spectral energy…

Solar and Stellar Astrophysics · Physics 2024-01-26 Theo Richardson , Adam Ginsburg , Rémy Indebetouw , Thomas P. Robitaille