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Related papers: Background-subtracted Solar Activity Maps

200 papers

We study the clustering of HI intensity maps produced from simulations with a focus on baryonic acoustic oscillations (BAO) and the effects induced by telescope beam smoothing and foreground cleaning. We start by creating a HI catalogue at…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-13 Santiago Avila , Bernhard Vos-Ginés , Steven Cunnington , Adam R. H. Stevens , Gustavo Yepes , Alexander Knebe , Chia-Hsun Chuang

We analyze 15 years of Fermi-LAT data and produce a detailed model of the Sun's inverse-Compton scattering emission (solar halo), which is powered by interactions between ambient cosmic-ray electrons and positrons with sunlight. By…

High Energy Astrophysical Phenomena · Physics 2026-01-28 Tim Linden , Jung-Tsung Li , Bei Zhou , Isabelle John , Milena Crnogorčević , Annika H. G. Peter , John F. Beacom

The contrasts and magnitude of observable signatures of small-scale features degrade as angular resolution decreases. High-cadence time-series of synthetic observable maps at 1.25 mm were produced from 3D magnetohydrodynamic Bifrost…

Solar and Stellar Astrophysics · Physics 2023-01-18 Henrik Eklund

We investigate spatio-temporal evolution of high-degree acoustic mode frequencies of the Sun and the surface magnetic activity, over the course of multiple solar cycles, to improve our understanding of the connection between the solar…

Solar and Stellar Astrophysics · Physics 2023-12-20 Mackenzie A. Baird , Sushanta C. Tripathy , Kiran Jain

The magnetic activity of the Sun directly impacts the Earth and human life. Likewise, other stars will have an impact on the habitability of planets orbiting these host stars. The lack of information on the magnetic field in the higher…

The long term study of the Sun is necessary if we are to determine the evolution of sunspot properties and thereby inform modeling of the solar dynamo, particularly on scales of a solar cycle. We aim to determine a number of sunspot…

Solar and Stellar Astrophysics · Physics 2011-08-23 Fraser T. Watson , Lyndsay Fletcher , Stephen Marshall

This study aims at introducing two conservative thermodynamic variables (moist-air entropy potential temperature and total water content) into a one-dimensional variational data assimilation system (1D-Var) to demonstrate the benefit for…

Atmospheric and Oceanic Physics · Physics 2022-04-12 Pascal Marquet , Pauline Martinet , Jean-François Mahfouf , Alina Lavinia Barbu , Benjamin Ménétrier

Modern deep learning models are over-parameterized, where different optima can result in widely varying generalization performance. The Sharpness-Aware Minimization (SAM) technique modifies the fundamental loss function that steers gradient…

On modern satellite observations of the Sun in the continuum with high spatial resolution, as well as on high-quality ground observations, a large number of small dark areas can be observed. These regions have no penumbra, have a contrast…

Solar and Stellar Astrophysics · Physics 2022-06-08 Andrey G. Tlatov

High cadence, multi-wavelength observations and simulations are employed for the analysis of solar photospheric magnetic bright points (MBPs) in the quiet Sun. The observations were obtained with the Rapid Oscillations in the Solar…

Solar and Stellar Astrophysics · Physics 2015-06-11 P. H. Keys , M. Mathioudakis , D. B. Jess , S. Shelyag , D. J. Christian , F. P. Keenan

Magneto-static models may overcome some of the issues facing force-free magnetic field extrapolations. So far they have seen limited use and have faced problems when applied to quiet-Sun data. Here we present a first application to an…

The analyses of sunspot observations revealed a fundamental magnetic property of the umbral boundary, the invariance of the vertical component of the magnetic field. We aim to analyse the magnetic properties of the umbra-penumbra boundary…

Solar and Stellar Astrophysics · Physics 2020-07-01 Jan Jurcak , Markus Schmassmann , Matthias Rempel , Nazaret Bello Gonzalez , Rolf Schlichenmaier

Breakthroughs in our understanding of physical phenomena have traditionally followed improvements in instrumentation. Studies of the magnetic field of the Sun, and its influence on the solar dynamo and space weather events, have benefited…

The aim of this work is to investigate the applications of the neutral atom imaging to the environments of the Earth, Mars and Mercury. This innovative technique permits the study of energetic plasma by means of analysing the result of the…

Earth and Planetary Astrophysics · Physics 2023-02-23 Alessandro Mura

We report the simultaneous presence of chromospheric umbral flashes and associated umbral waves, and propagating coronal disturbances, in a sunspot and related active region. We have analyzed time-distance maps obtained using the…

Solar and Stellar Astrophysics · Physics 2017-12-13 Aishawnnya Sharma , G. R. Gupta , Durgesh Tripathi , V. Kashyap , Amit Pathak

The solar mean magnetic field (SMMF) is referred to as the disc-averaged line-of-sight (LOS) magnetic field that also reflects the polarity imbalance of the magnetic field on the Sun. The origin of the SMMF has been debated over the past…

Solar and Stellar Astrophysics · Physics 2018-08-13 Souvik Bose , K. Nagaraju

The Visible-light Imager and Magnetograph (VIM) proposed for the ESA Solar Orbiter mission will observe a photospheric spectral line at high spatial resolution. Here we simulate and interpret VIM measurements. Realistic MHD models are used…

We compared magnetograms from the KPVT/SPM, SoHO/MDI, SOLIS/VSM, and SDO/HMI with the aim of probing the effect on measured solar magnetism of the variation in instrument response with time, magnetogram signal level, and position on the…

Solar and Stellar Astrophysics · Physics 2024-05-24 K. L. Yeo , S. K. Solanki , N. A. Krivova

Solar variability investigations that include magnetic energy coupling are paramount to solving many key solar/stellar physics problems, particularly for understanding the temporal variability of magnetic energy redistribution and heating…

Solar and Stellar Astrophysics · Physics 2016-12-28 N. Brice Orange , David L. Chesny , Bruce Gendre , David C. Morris , Hakeem M. Oluseyi

Modern soil mapping is characterised by the need to interpolate samples of geostatistical response observations and the availability of relatively large numbers of environmental characteristics for consideration as covariates to aid this…

Applications · Statistics 2016-09-09 Benjamin R. Fitzpatrick , David W. Lamb , Kerrie Mengersen