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Related papers: Helioseismic Detection of Emerging Magnetic Flux

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We investigate the emergence of Active Region NOAA 10790 by means of time--distance helioseismology. Shallow regions of increased sound speed at the location of increased magnetic activity are observed, with regions becoming deeper at the…

Astrophysics · Physics 2009-11-13 S. Zharkov , M. J. Thompson

Magnetic fields emerging from the Sun's interior carry information about physical processes of magnetic field generation and transport in the convection zone. Soon after appearance on the solar surface the magnetic flux gets concentrated in…

Solar and Stellar Astrophysics · Physics 2009-11-13 A. G. Kosovichev

In this Letter we present a seismological detection of a rising motion of magnetic flux in the shallow convection zone of the Sun, and show estimates of the emerging speed and its decelerating nature. In order to evaluate the speed of…

Solar and Stellar Astrophysics · Physics 2015-06-15 Shin Toriumi , Stathis Ilonidis , Takashi Sekii , Takaaki Yokoyama

We studied 101 flux emergence events ranging from small ephemeral regions to large emerging flux regions which were observed with Hinode Solar Optical Telescope filtergram. We investigated how the total magnetic flux of the emergence event…

Solar and Stellar Astrophysics · Physics 2015-05-28 Kenichi Otsuji , Reizaburo Kitai , Kiyoshi Ichimoto , Kazunari Shibata

The solar interior is filled with turbulent thermal convection, which plays a key role in the energy and momentum transport and the generation of the magnetic field. The turbulent flows in the solar interior cannot be optically detected due…

Solar and Stellar Astrophysics · Physics 2024-10-10 Hiroyuki Masaki , Hideyuki Hotta

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

Time-distance helioseismic measurements in surface- and deep-focus geometries for wave-paths that distinguish surface magnetic contributions from those due to deeper perturbations beneath a large sunspot are presented and analysed. Travel…

Astrophysics · Physics 2008-02-21 S. P. Rajaguru

A time-distance helioseismic technique, similar to the one used by Ilonidis et al (2011), is applied to two independent numerical models of subsurface sound-speed perturbations to determine the spatial resolution and accuracy of phase…

Solar and Stellar Astrophysics · Physics 2021-06-02 John T. Stefan , Alexander G. Kosovichev , Andrey M. Stejko

Magnetic flux emergence from the convection zone into the photosphere and beyond is a critical component of the behaviour of large-scale solar magnetism. Flux rarely emerges amid field-free areas at the surface, but when it does, the…

Solar and Stellar Astrophysics · Physics 2024-03-04 Prasad Mani , Chris S. Hanson , Siddarth Dhanpal , Shravan Hanasoge , Srijan Bharati Das , Matthias Rempel

Solar active regions (ARs) are thought to be formed by magnetic fields from the convection zone. Our flux emergence simulations revealed that a strong horizontal divergent flow (HDF) of unmagnetized plasma appears at the photosphere before…

Solar and Stellar Astrophysics · Physics 2015-06-22 Shin Toriumi , Keiji Hayashi , Takaaki Yokoyama

Aims. Moreno-Insertis et al. (2018) recently discovered two types of flux emergence in their numerical simulations: magnetic loops and magnetic sheet emergence. Whereas magnetic loop emergence has been documented well in the last years, by…

Solar and Stellar Astrophysics · Physics 2019-02-13 C. E. Fischer , J. M. Borrero , N. Bello González , A. J. Kaithakkal

Small-scale internetwork (IN) features are thought to be the major source of fresh magnetic flux in the quiet Sun. During its first science flight in 2009, the balloon-borne observatory Sunrise captured images of the magnetic fields in the…

Solar and Stellar Astrophysics · Physics 2017-03-29 H. N. Smitha , L. S. Anusha , S. K. Solanki , T. Riethmueller

A cooperative observation with Hida observatory and Hinode satellite was performed on an emerging flux region. The successive Ca II K spectro-heliograms of the emerging flux region were taken by the Domeless Solar Telescope of Hida…

Small-scale magnetic flux emergence in the quiet Sun is crucial for maintaining solar magnetic activity. On the smallest scales studied so far, namely within individual granules, two mechanisms have been identified: emergence in tiny…

Solar and Stellar Astrophysics · Physics 2025-03-05 S. M. Díaz-Castillo , C. E. Fischer , F. Moreno-Insertis , S. L. Guglielmino , R. Ishikawa , S. Criscuoli

Aims: We investigate the temporal evolution of magnetic flux emergence in the quiet Sun atmosphere close to disk center. Methods: We combine high-resolution SoHO/MDI magnetograms with TRACE observations taken in the 1216 {\AA} channel in…

Solar and Stellar Astrophysics · Physics 2015-06-16 P. Gömöry , H. Balthasar , K. G. Puschmann

We investigate deviations in the mean phase travel time of acoustic waves preceding the emergence of 46 large active regions observed by the Helioseismic and Magnetic Imager (HMI). In our investigation, we consider two different procedures…

Solar and Stellar Astrophysics · Physics 2023-05-03 John Stefan , Alexander Kosovichev

To create early warning capabilities for upcoming Space Weather disturbances, we have selected a dataset of 61 emerging active regions, which allows us to identify characteristic features in the evolution of acoustic power density to…

Solar and Stellar Astrophysics · Physics 2024-12-25 Spiridon Kasapis , Irina N. Kitiashvili , Alexander G. Kosovichev , John T. Stefan , Bhairavi Apte

Magnetic helicity flux gives information about the topology of a magnetic field passing through a boundary. In solar physics applications, this boundary is the photosphere and magnetic helicity flux has become an important quantity in…

Solar and Stellar Astrophysics · Physics 2019-04-03 Chris Prior , David MacTaggart

It is widely accepted that solar active regions including sunspots are formed by the emerging magnetic flux from the deep convection zone. In previous numerical simulations, we found that the horizontal divergent flow (HDF) occurs before…

Solar and Stellar Astrophysics · Physics 2015-06-04 S. Toriumi , K. Hayashi , T. Yokoyama

We use observations of line-of-sight magnetograms from Helioseismic and Magnetic Imager (HMI) on board of Solar Dynamics Observatory (SDO) to investigate polarity separation, magnetic flux, flux emergence rate, twist and tilt of solar…

Solar and Stellar Astrophysics · Physics 2019-02-20 A. S. Kutsenko , V. I. Abramenko , A. A. Pevtsov
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