Počet záznamů: 1
Horizontal motions in sunspot penumbrae
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SYSNO ASEP 0558170 Druh ASEP J - Článek v odborném periodiku Zařazení RIV J - Článek v odborném periodiku Poddruh J Článek ve WOS Název Horizontal motions in sunspot penumbrae Tvůrce(i) Sobotka, Michal (ASU-R) RID, ORCID
Puschmann, K.G. (DE)Celkový počet autorů 2 Číslo článku A13 Zdroj.dok. Astronomy & Astrophysics. - : EDP Sciences - ISSN 0004-6361
Roč. 662, May (2022)Poč.str. 6 s. Forma vydání Online - E Jazyk dok. eng - angličtina Země vyd. FR - Francie Klíč. slova Sun ; photosphere ; sunspots Vědní obor RIV BN - Astronomie a nebeská mechanika, astrofyzika Obor OECD Astronomy (including astrophysics,space science) Způsob publikování Open access Institucionální podpora ASU-R - RVO:67985815 UT WOS 000803310700007 EID SCOPUS 85131254009 DOI https://doi.org/10.1051/0004-6361/202243577 Anotace 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.
Pracoviště Astronomický ústav Kontakt Anežka Melichárková, bibl@asu.cas.cz, Tel.: 323 620 326 Rok sběru 2023 Elektronická adresa http://hdl.handle.net/11104/0332249
Počet záznamů: 1