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Related papers: Tracking granules on the Sun's surface and reconst…

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Granular materials such as gravel, cereals, or pellets, are ubiquitous in nature, daily life, and industry. While sharing some characteristics with gases, liquids, and solids, granular matter exhibits a wealth of phenomena that defy these…

Soft Condensed Matter · Physics 2025-03-31 Mathieu Suter , Jens P. Metzger , Andreas Port , Christoph R. Müller , Klaas P. Pruessmann

Radial differential rotation is an important factor in stellar dynamo theory. In the Sun, helioseismology has revealed a near surface shear layer in the upper 5 to 10% of the convection zone. At low to midlatitudes, the rotation velocity…

Solar and Stellar Astrophysics · Physics 2025-10-15 T. Corbard , M. Faurobert , B. Gelly , R. Douet , D. Laforgue

We report on the serendipitous observations of Solar System objects imaged during the High cadence Transient Survey (HiTS) 2014 observation campaign. Data from this high cadence, wide field survey was originally analyzed for finding…

Symmetry detection and morphological classification of anatomical structures play pivotal roles in medical image analysis. The application of kinematic surface fitting, a method for characterizing shapes through parametric stationary…

Computer Vision and Pattern Recognition · Computer Science 2024-01-30 Wilhelm Wimmer , Hervé Delingette

We present an experimental investigation of the statistical properties of spherical granular particles on an inclined plane that are excited by an oscillating side-wall. The data is obtained by high-speed imaging and particle tracking…

Soft Condensed Matter · Physics 2009-11-07 Daniel L. Blair , A. Kudrolli

Context. The interaction of solar oscillations with near surface convection is poorly understood. These interactions are likely the cause of several problems in helio- and astero-seismology, including the so-called surface effect and…

Solar and Stellar Astrophysics · Physics 2015-08-19 J. Schou

We present a machine learning method to assign stellar parameters (temperature, surface gravity, metallicity) to the photometric data of large photometric surveys such as SDSS and SKYMAPPER. The method makes use of our previous effort in…

Instrumentation and Methods for Astrophysics · Physics 2024-12-09 A. Turchi , E. Pancino , F. Rossi , A. Avdeeva , P. Marrese , S. Marinoni , N. Sanna , M. Tsantaki , G. Fanari

To obtain cm/s precision, stellar surface magneto-convection must be disentangled from observed radial velocities (RVs). In order to understand and remove the convective signature, we create Sun-as-a-star model observations based on a 3D…

Solar and Stellar Astrophysics · Physics 2014-08-22 H. M. Cegla , C. A. Watson , S. Shelyag , M. Mathioudakis

Owing to recent advances in radial-velocity instrumentation and observation techniques, the detection of Earth-mass planets around Sun-like stars may soon be primarily limited by intrinsic stellar variability. Several processes contribute…

Solar and Stellar Astrophysics · Physics 2021-12-22 Michael L. Palumbo , Eric B. Ford , Jason T. Wright , Suvrath Mahadevan , Alexander W. Wise , Johannes Löhner-Böttcher

The investigation of the statistical properties of maps of line centroids has been used for almost 50 years, but there is still no general agreement on their interpretation. We try to quantify which properties of underlying turbulent…

Astrophysics · Physics 2009-11-11 V. Ossenkopf , A. Esquivel , A. Lazarian , J. Stutzki

Radial velocity perturbations induced by stellar surface inhomogeneities including spots, plages and granules currently limit the detection of Earth-twins using Doppler spectroscopy. Such stellar noise is poorly understood for stars other…

In recent years supergranulation has emerged as one of the biggest challenges for the detection of Earth-twins in radial velocity planet searches. We used eight years of Sun-as-a-star radial velocity observations from HARPS-N to measure the…

Polarization of starlight induced by dust grains aligned with the magnetic field (hereafter B-field) is widely used to measure the two-dimensional B-fields projected onto the plane-of-sky. Here, we introduce a new method to infer…

Astrophysics of Galaxies · Physics 2025-02-04 Bao Truong , Thiem Hoang

Purpose: Lung nodule segmentation, i.e., the algorithmic delineation of the lung nodule surface, is a fundamental component of computational nodule analysis pipelines. We propose a new method for segmentation that is a machine learning…

Image and Video Processing · Electrical Eng. & Systems 2021-01-20 Matthew C Hancock , Jerry F Magnan

The goal of video segmentation is to turn video data into a set of concrete motion clusters that can be easily interpreted as building blocks of the video. There are some works on similar topics like detecting scene cuts in a video, but…

Computer Vision and Pattern Recognition · Computer Science 2019-03-07 Hajar Sadeghi Sokeh , Vasileios Argyriou , Dorothy Monekosso , Paolo Remagnino

Grid maps are widely used in robotics to represent obstacles in the environment and differentiating dynamic objects from static infrastructure is essential for many practical applications. In this work, we present a methods that uses a deep…

Computer Vision and Pattern Recognition · Computer Science 2017-09-12 Florian Piewak , Timo Rehfeld , Michael Weber , J. Marius Zöllner

Solar image analysis relies on the detection of coronal holes for predicting disruptions to earth's magnetic field. The coronal holes act as sources of solar wind that can reach the earth. Thus, coronal holes are used in physical models for…

Solar and Stellar Astrophysics · Physics 2022-07-21 Venkatesh Jatla

Spectral analysis is a powerful tool to investigate stellar properties and it has been widely used for decades now. However, the methods considered to perform this kind of analysis are mostly based on iteration among a few diagnostic lines…

Instrumentation and Methods for Astrophysics · Physics 2015-09-30 J-M. Mugnes , C. Robert

Investigations of mass segregation are of vital interest for the understanding of the formation and dynamical evolution of stellar systems on a wide range of spatial scales. Our method is based on the minimum spanning tree (MST) that serves…

Astrophysics of Galaxies · Physics 2015-05-28 C. Olczak , R. Spurzem , Th. Henning

In the quiet regions on the solar surface, turbulent convective motions of granulation play an important role in creating small-scale magnetic structures, as well as in energy injection into the upper atmosphere. The turbulent nature of…

Solar and Stellar Astrophysics · Physics 2020-03-04 Ryohtaroh T. Ishikawa , Yukio Katsukawa , Takayoshi Oba , Motoki Nakata , Kenichi Nagaoka , Tatsuya Kobayashi