Horizontal motions in sunspot penumbrae

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985815%3A_____%2F22%3A00558170" target="_blank" >RIV/67985815:_____/22:00558170 - isvavai.cz</a>

Result on the web

<a href="http://hdl.handle.net/11104/0332249" target="_blank" >http://hdl.handle.net/11104/0332249</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1051/0004-6361/202243577" target="_blank" >10.1051/0004-6361/202243577</a>

Result language

angličtina

Original language name

Horizontal motions in sunspot penumbrae

Original language description

A model of penumbral filaments represented by magnetoconvective cells was derived recently from spectropolarimetric observations. High-resolution observations of horizontal motions in the penumbra are needed to complement the concept of penumbrae obtained from spectropolarimetry. Time series of images of a large sunspot acquired with the Swedish Solar Telescope are analysed. Horizontal motions of penumbral grains (PGs), structures in dark bodies of filaments, the outer penumbral border, and G-band bright points are measured in time slices. In the inner penumbra, PGs move towards the umbra (inwards) with a mean speed of -0.7 km/s. The direction of motion changes from inwards to outwards at approximately 60% of the penumbral width, and the mean speed increases gradually in the outer penumbra, approaching 0.5 km/s. This speed is also typical of an expansion of the penumbra–granulation border. The majority of the G-band bright points moves away from the sunspot, with a typical speed of 0.6 km/s. High outward speeds, 3.6 km/s on average, are observed in dark bodies of penumbral filaments. According to the model of penumbral filaments, it is suggested that the speeds detected in the dark bodies of filaments are associated with the Evershed flow and that the opposite directions of PG motions in the inner and outer penumbrae may be explained by the interaction of rising plasma in filament heads with a surrounding, differently inclined magnetic field.n

Czech name

—

Czech description

—

Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

10308 - Astronomy (including astrophysics,space science)

Project

—

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2022

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Astronomy & Astrophysics

ISSN

0004-6361

e-ISSN

1432-0746

Volume of the periodical

662

Issue of the periodical within the volume

May

Country of publishing house

FR - FRANCE

Number of pages

6

Pages from-to

A13

UT code for WoS article

000803310700007

EID of the result in the Scopus database

2-s2.0-85131254009