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Related papers: Magnetic field vector retrieval with HMI

200 papers

This paper reports high-precision Stokes V spectra of HD 191612 acquired using the ESPaDOnS spectropolarimeter at the Canada-France-Hawaii Telescope, in the context of the Magnetism in Massive stars (MiMeS) Project. Using measurements of…

Recent studies indicate that a small number of rogue solar active regions (ARs) may have a significant impact on the end-of-cycle polar field and the long-term behavior of solar activity. The impact of individual ARs can be qualified based…

Solar and Stellar Astrophysics · Physics 2024-05-13 Ruihui Wang , Jie Jiang , Yukun Luo

Direct comparison between stellar and solar magnetic maps are hampered by their dramatic differences in resolution. Here, we present a method to filter out the small-scale component of vector fields, in such a way that comparison between…

Solar and Stellar Astrophysics · Physics 2016-04-20 A. A. Vidotto

The magnetometer (MAG) on Voyager 1 (V1) has been sampling the interstellar magnetic field (ISMF) since August 2012. The V1 MAG observations have shown draped ISMF in the very local interstellar medium disturbed occasionally by significant…

Space Physics · Physics 2017-07-26 Tae K. Kim , Nikolai V. Pogorelov , Leonard F. Burlaga

The Sun's surface field, especially the polar field, sets the boundary condition for the coronal and heliospheric magnetic fields, but also provides us insight into the dynamo process. The evolution of the polar fields results from the…

Solar and Stellar Astrophysics · Physics 2018-07-05 Jie Jiang , Jinbin Cao

This article presents a publicly available, multimodal, tiered magnetic polarity inversion lines (MPILs) dataset extracted from the Solar Dynamics Observatory's (SDO) Helioseismic and Magnetic Imager (HMI) Active Region Patches (SDO/HMI…

Solar and Stellar Astrophysics · Physics 2025-08-26 Ziba Khani , Anli Ji , Manolis K. Georgoulis , Berkay Aydin

We present several methods towards construction of precursors, which show great promise towards early predictions, of solar flare events in this paper. A data pre-processing pipeline is built to extract useful data from multiple sources,…

Solar and Stellar Astrophysics · Physics 2020-01-08 Yang Chen , Ward B. Manchester , Alfred O. Hero , Gabor Toth , Benoit DuFumier , Tian Zhou , Xiantong Wang , Haonan Zhu , Zeyu Sun , Tamas I. Gombosi

Using even-order frequency splitting coefficients of global p-modes it is possible to infer the magnetic field in the solar interior as a function of radial distance and latitude. Results obtained using GONG and MDI data are discussed.…

Astrophysics · Physics 2007-05-23 H. M. Antia

We search for observational signatures of magnetic helicity in data from all-sky radio polarization surveys of the Milky Way Galaxy. Such a detection would help confirm the dynamo origin of the field and may provide new observational…

Astrophysics of Galaxies · Physics 2020-10-14 J. L. West , R. N. Henriksen , K. Ferrière , A. Woodfinden , T. Jaffe , B. M. Gaensler , J. A. Irwin

The effects of acoustic wave absorption, mode conversion and transmission by a sunspot on the helioseismic inferences are widely discussed, but yet accounting for them has proved difficult for lack of a consistent framework within…

Solar and Stellar Astrophysics · Physics 2012-06-26 S. P. Rajaguru

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

The purpose of this white paper is to put together a coherent vision for the role of helioseismic monitoring of magnetic activity in the Sun's far hemisphere that will contribute to improving space weather forecasting as well as fundamental…

The determination of the magnetic filed vector in solar filaments is possible by interpreting the Hanle and Zeeman effects in suitable chromospheric spectral lines like those of the He I multiplet at 10830 A. We study the vector magnetic…

Solar and Stellar Astrophysics · Physics 2019-05-29 C. J. Díaz Baso , M. J. Martínez González , A. Asensio Ramos

The distribution and evolution of the magnetic field at the solar poles through a solar cycle is an important parameter in understanding the solar dynamo. The accurate observations of the polar magnetic flux is very challenging from the…

Solar and Stellar Astrophysics · Physics 2024-07-26 Sanjay Gosain , Han Uitenbroek

This paper introduces a high resolution, machine learning-ready heliophysics dataset derived from NASA's Solar Dynamics Observatory (SDO), specifically designed to advance machine learning (ML) applications in solar physics and space…

Time-distance helioseismology provides information about vector flows in the near-surface layers of the Sun by measuring wave travel times between points on the solar surface. Specific spatial averages of travel times have been proposed for…

Solar and Stellar Astrophysics · Physics 2015-01-05 Jan Langfellner , Laurent Gizon , Aaron C. Birch

Our current knowledge about the stellar magnetic fields relies almost entirely on the circular polarization observations. Very few objects have been observed so far in all four Stokes parameters. The magnetic Ap star HD24712 (DO Eri,…

Solar and Stellar Astrophysics · Physics 2015-06-17 N. Rusomarov , O. Kochukhov , N. Piskunov

The immense volume of data generated by the suite of instruments on SDO requires new tools for efficient identifying and accessing data that is most relevant to research investigations. We have developed the Heliophysics Events…

Instrumentation and Methods for Astrophysics · Physics 2012-01-23 N. Hurlburt , M. Cheung , C. Schrijver , L. Chang , S. Freeland , S. Green , C. Heck , A. Jaffey , A. Kobashi , D. Schiff , J. Serafin , R. Seguin , G. Slater , A. Somani , R. Timmons

We report observations of a white-light solar flare (SOL2010-06-12T00:57, M2.0) observed by the Helioseismic Magnetic Imager (HMI) on the Solar Dynamics Observatory (SDO) and the Reuven Ramaty High-Energy Solar Spectroscopic Imager…

Solar and Stellar Astrophysics · Physics 2015-05-20 J. C. Martinez Oliveros , S. Couvidat , J. Schou , S. Krucker , C. Lindsey , H. S. Hudson , P. Scherrer

Magnetography using magnetic sensitive lines is regarded traditionally as the main instrument for measuring the magnetic field of the whole Sun. Full polarized Stockes parameters ($I$, $Q$, $U$, $V$) observed can be used to deduce the…

Solar and Stellar Astrophysics · Physics 2022-01-19 S. Liu , J. T. Su , X. Y. Bai , Y. Y Deng , J. Chen , Y. L. Song , X. F. Wang , H. Q. Xu , X. Yang