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Related papers: HMI Synoptic Maps Produced by NSO/NISP

200 papers

We study properties of waves of frequencies above the photospheric acoustic cut-off of $\approx$5.3 mHz, around four active regions, through spatial maps of their power estimated using data from Helioseismic and Magnetic Imager (HMI) and…

Solar and Stellar Astrophysics · Physics 2015-06-05 S. P. Rajaguru , S. Couvidat , Xudong Sun , K. Hayashi , H. Schunker

Here we greatly improve Artificial Intelligence (AI)-generated solar farside magnetograms using data sets of Solar Terrestrial Relations Observatory (STEREO) and Solar Dynamics Observatory (SDO). We modify our previous deep learning model…

Solar and Stellar Astrophysics · Physics 2022-10-26 Hyun-Jin Jeong , Yong-Jae Moon , Eunsu Park , Harim Lee , Ji-Hye Baek

We report our first results on comparing the variations of the solar internal rotation with solar activity, as predicted by non-linear solar dynamo modelling, with helioseismic measurements using the SOHO MDI data.

Astrophysics · Physics 2007-05-23 S. Vorontsov , R. Tavakol , E. Covas , D. Moss

Among many other measurable quantities the summer of 2009 saw a considerable low in the radiative output of the Sun that was temporally coincident with the largest cosmic ray flux ever measured at 1AU. A hemispheric asymmetry in magnetic…

In this dissertation, several components of large-scale solar flows are studied observationally: solar equatorial Rossby waves (waves of radial vorticity), large-scale convection, and surface flows around active regions. Maps of horizontal…

Solar and Stellar Astrophysics · Physics 2023-01-25 Bastian Proxauf

We propose a forecasting approach for solar flares based on data from Solar Cycle 24, taken by the Helioseismic and Magnetic Imager (HMI) on board the Solar Dynamics Observatory (SDO) mission. In particular, we use the Space-weather HMI…

In this work, we focus in the magnetic evolution of a small region as seen by Hinode-SP during the time interval of about one hour. High-cadence LOS magnetograms and velocity maps were derived, allowing the study of different small-scale…

Solar and Stellar Astrophysics · Physics 2012-09-05 J. Palacios , L. A. Balmaceda , S. Vargas Domínguez , I. Cabello , V. Domingo

Context. In local helioseismology, the travel times of acoustic waves propagating in opposite directions along the same meridian inform us about horizontal flows in the north-south direction. The longitudinal averages of the north-south…

Solar and Stellar Astrophysics · Physics 2022-08-31 Paul-Louis Poulier , Zhi-Chao Liang , Damien Fournier , Laurent Gizon

The solar group at the National Astronomical Observatory of Japan is conducting synoptic solar observations with the Solar Flare Telescope. While it is a part of a long-term solar monitoring, contributing to the study of solar dynamo…

Solar and Stellar Astrophysics · Physics 2020-09-29 Yoichiro Hanaoka , Takashi Sakurai , Ken'ichi Otsuji , Isao Suzuki , Satoshi Morita

Local helioseismology provides a unique opportunity to investigate the subsurface structure and dynamics of active regions and their effect on the large-scale flows and global circulation of the Sun. We use measurements of plasma flows in…

Solar and Stellar Astrophysics · Physics 2016-07-19 Alexander G. Kosovichev , Junwei Zhao , Stathis Ilonidis

Current ground-based submillimeter instruments (e.g. SCUBA-2, SHARC-2 and LABOCA) have hundreds to thousands of detectors, sampled at tens to hundreds of hertz, generating up to hundreds of gigabytes per night. Since noise is correlated…

Instrumentation and Methods for Astrophysics · Physics 2014-05-05 Gaelen Marsden , Adam Brazier , Tim Jenness , Jack Sayers , Douglas Scott

The measurement of the Sun's surface motions with a high spatial and temporal resolution is still a challenge. We wish to validate horizontal velocity measurements all over the visible disk of the Sun from Solar Dynamics Observatory/…

Solar and Stellar Astrophysics · Physics 2015-06-15 Th. Roudier , M. Rieutord , V. Prat , J. M. Malherbe , N. Renon , Z. Frank , M. Svanda , T. Berger , R. Burston , L. Gizon

We analyze spectral properties of solar convection in the range of depths from 0 to 19~Mm using subsurface flow maps obtained by the time-distance heiioseismology analysis of solar-oscillation data from the Helioseismic and Magnetic Imager…

Solar and Stellar Astrophysics · Physics 2022-03-01 Alexander V. Getling , Alexander G. Kosovichev

Photospheric magnetic vector maps from two different instruments are used to model the nonlinear force-free coronal magnetic field above an active region. We use vector maps inferred from polarization measurements of the Solar Dynamics…

Solar and Stellar Astrophysics · Physics 2015-06-15 J. K. Thalmann , S. K. Tiwari , T. Wiegelmann

Besides their own intrinsic interest, correct interpretation of solar surface magnetic field observations is crucial to our ability to describe the global magnetic structure of the solar atmosphere. Photospheric magnetograms are often used…

Solar and Stellar Astrophysics · Physics 2010-10-29 Gordon J. D. Petrie , Irina Patrikeeva

We create the first large-scale mock spectroscopic survey of gas absorption sightlines traversing the interstellar medium (ISM), circumgalactic medium (CGM), and intergalactic medium (IGM) surrounding galaxies of virtual Universes. That is,…

Multi--wavelength studies of energetic solar flares with seismic emissions have revealed interesting common features between them. We studied the first GOES X--class flare of the 24th solar cycle, as detected by the Solar Dynamics…

Solar and Stellar Astrophysics · Physics 2015-06-04 J. D. Alvarado-Gómez , J. C. Buitrago-Casas , J. C. Martínez-Oliveros , C. Lindsey , H. Hudson , B. Calvo-Mozo

Helioseismology has produced unprecedented measurements of the Sun's internal structure and dynamics over the past 25 years. Much of this work has been based on global helioseismology. Now local helioseismology too is showing its great…

Solar and Stellar Astrophysics · Physics 2010-03-23 M. J. Thompson

The productions of data with internationally agreed standards are the common pursuits for all astronomical observation instruments both ground and spacebased undoubtedly, Since standard data to facilitate the use of scientific research. The…

Solar and Stellar Astrophysics · Physics 2019-02-04 S. Liu , X. Yang , C. Zhao , G. H. Lin

Observations of cosmic microwave background polarisation, essential for probing a potential phase of inflation in the early universe, suffer from contamination by polarised emission from the Galactic interstellar medium. This work combines…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-25 Jacques Delabrouille