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Related papers: The simulation of realistic BiSON-like helioseismi…

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We present a numerical method for modelling noise in Stimulated Brillouin Scattering (SBS). The model applies to dynamic cases such as optical pulses, and accounts for both thermal noise and phase noise from the input lasers. Using this…

Global hydrodynamic simulations of internal solar dynamics have focused on replicating the conditions for solar-like differential rotation and meridional circulation using the results of helioseismic inversions as a constraint. Inferences…

The Laser Interferometer Space Antenna (LISA) aims to observe gravitational waves in the mHz regime over its 10-year mission time. LISA will operate laser interferometers between three spacecrafts. Each spacecraft will utilize independent…

Instrumentation and Methods for Astrophysics · Physics 2022-03-03 Kohei Yamamoto , Christoph Vorndamme , Olaf Hartwig , Martin Staab , Thomas S. Schwarze , Gerhard Heinzel

In this article, we introduce a methodology based on an analytical model of a damped harmonic oscillator subject to random forcing to generate transient gravitational wave signals. Such a model incorporates a simulated linear high-frequency…

General Relativity and Quantum Cosmology · Physics 2024-07-04 César Tiznado , Alejandro Casallas-Lagos , Javier M. Antelis , Claudia Moreno

We present a detailed comparison of three different simulations of the epoch of reionization (EoR). The radiative transfer simulation (${\rm C}^2$-RAY) among them is our benchmark. Radiative transfer codes can produce realistic results, but…

Cosmology and Nongalactic Astrophysics · Physics 2014-08-07 Suman Majumdar , Garrelt Mellema , Kanan K. Datta , Hannes Jensen , T. Roy Choudhury , Somnath Bharadwaj , Martina M. Friedrich

This study investigates the noise characteristics of intraoperative X-ray fluoroscopic images acquired during real-time image-guided radiotherapy (IGRT), and presents a novel noise image generation method based on the identified noise…

Medical Physics · Physics 2024-11-04 Yongxuan Yan , Fumitake Fujii , Takehiro Shiinoki

A number of experiments are set to measure the 21-cm signal of neutral hydrogen from the Epoch of Reionization (EoR). The common denominator of these experiments are the large data sets produced, contaminated by various instrumental…

Long-baseline optical interferometry uses the power spectrum and bispectrum constructs as fundamental observables. Noise arising in the detection of the fringe pattern gives rise to both variance and biases in the power spectrum and…

Instrumentation and Methods for Astrophysics · Physics 2015-05-28 J. A. Gordon , D. F. Buscher

We present a method for simulating the time evolution of one-dimensional correlated electron-phonon systems which combines the time-evolving block decimation algorithm with a dynamical optimization of the local basis. This approach can…

Strongly Correlated Electrons · Physics 2015-12-16 Christoph Brockt , Florian Dorfner , Lev Vidmar , Fabian Heidrich-Meisner , Eric Jeckelmann

Helioseismic holography is an imaging technique used to study heterogeneities and flows in the solar interior from observations of solar oscillations at the surface. Holograms contain noise due to the stochastic nature of solar…

Solar and Stellar Astrophysics · Physics 2018-12-12 Laurent Gizon , Damien Fournier , Dan Yang , Aaron C. Birch , Hélène Barucq

Investigation of propagation, conversion, and scattering of MHD waves in the Sun is very important for understanding the mechanisms of observed oscillations and waves in sunspots and active regions. We have developed 3D linear MHD numerical…

Astrophysics · Physics 2011-02-11 K. V. Parchevsky , A. G. Kosovichev

Denoising diffusion probabilistic models are able to generate synthetic sensor signals. The training process of such a model is controlled by a loss function which measures the difference between the noise that was added in the forward…

Machine Learning · Computer Science 2025-11-27 Heiko Oppel , Andreas Spilz , Michael Munz

Simulating the distribution of cosmological neutral hydrogen (HI) during the epoch of reionization requires a high dynamic range and is hence computationally expensive. The size of the simulation is dictated by the largest scales one aims…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-24 Ankur Barsode , Tirthankar Roy Choudhury

This paper presents a one-dimensional time-dependent numerical model of a sea organ, which generates music driven by the motion of the sea. The governing equations are derived by coupling hydrodynamic and thermodynamic equations for water…

Fluid Dynamics · Physics 2019-03-25 Nino Krvavica , Gabrijel Peroli , Igor Ružić , Nevenka Ožanić

Linear time-distance helioseismic inversions are carried out using several filtering schemes to determine vector flow velocities within two $\sim100^2\,{\rm Mm^2}\times 20\,{\rm Mm}$ realistic magnetohydrodynamic sunspot simulations of…

Solar and Stellar Astrophysics · Physics 2015-06-22 K. DeGrave , J. Jackiewicz , M. Rempel

Bosonic quantum devices offer a novel approach to realize quantum computations, where the quantum two-level system (qubit) is replaced with the quantum (an)harmonic oscillator (qumode) as the fundamental building block of the quantum…

We investigate the errors in modeling the redshift-space distortion (RSD) effect at large linear scales, using data from the Millennium simulation. While standard theoretical templates, such as the Kaiser formula and the TNS method, could…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-29 Hongxiang Chen , Jie Wang , Baojiu Li

We describe a method for removing ionospheric effects from single-frequency radio data a posteriori. This method is based on a theoretical climatological model developed by the USAF, which returns electron density as a function of position…

Astrophysics · Physics 2009-10-31 R. M. Campbell

The LISA datastream will be populated by large instrumental and astrophysical noises, both potentially exhibiting long-term non-stationarities. Modelling and inferring on them is a challenging task, central for accurate signal…

Instrumentation and Methods for Astrophysics · Physics 2025-07-01 Federico Pozzoli , Riccardo Buscicchio , Antoine Klein , Daniele Chirico

We use Sun-as-a-star helioseismology data, collected by the Birmingham Solar-Oscillations Network (BiSON), to examine the relationship between the solar-cycle-induced frequency shifts of whole-Sun, low-angular degree solar p modes and…

Solar and Stellar Astrophysics · Physics 2026-05-29 William J. Chaplin , Sarbani Basu , Rachel Howe , Yvonne Elsworth , Steven J. Hale , Eleanor Murray