Large-scale photospheric motions determined from granule tracking and helioseismology from SDO/HMI data

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F18%3A10385951" target="_blank" >RIV/00216208:11320/18:10385951 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/67985815:_____/18:00495455

Výsledek na webu

<a href="https://doi.org/10.1051/0004-6361/201732014" target="_blank" >https://doi.org/10.1051/0004-6361/201732014</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1051/0004-6361/201732014" target="_blank" >10.1051/0004-6361/201732014</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Large-scale photospheric motions determined from granule tracking and helioseismology from SDO/HMI data

Popis výsledku v původním jazyce

Context. Large-scale flows in the Sun play an important role in the dynamo process linked to the solar cycle. The important large-scale flows are the differential rotation and the meridional circulation with an amplitude of km s 1 and few m s 1, respectively. These flows also have a cycle-related components, namely the torsional oscillations. Aims. Our attempt is to determine large-scale plasma flows on the solar surface by deriving horizontal flow velocities using the techniques of solar granule tracking, dopplergrams, and time-distance helioseismology. Methods. Coherent structure tracking (CST) and time-distance helioseismology were used to investigate the solar differential rotation and meridional circulation at the solar surface on a 30-day HMI/SDO sequence. The influence of a large sunspot on these large-scale flows with a specific 7-day HMI/SDO sequence has been also studied. Results. The large-scale flows measured by the CST on the solar surface and the same flow determined from the same data with the helioseismology in the first 1 Mm below the surface are in good agreement in amplitude and direction. The torsional waves are also located at the same latitudes with amplitude of the same order. We are able to measure the meridional circulation correctly using the CST method with only 3 days of data and after averaging between +/-15 degrees in longitude. Conclusions. We conclude that the combination of CST and Doppler velocities allows us to detect properly the differential solar rotation and also smaller amplitude flows such as the meridional circulation and torsional waves. The results of our methods are in good agreement with helioseismic measurements.

Název v anglickém jazyce

Large-scale photospheric motions determined from granule tracking and helioseismology from SDO/HMI data

Popis výsledku anglicky

Context. Large-scale flows in the Sun play an important role in the dynamo process linked to the solar cycle. The important large-scale flows are the differential rotation and the meridional circulation with an amplitude of km s 1 and few m s 1, respectively. These flows also have a cycle-related components, namely the torsional oscillations. Aims. Our attempt is to determine large-scale plasma flows on the solar surface by deriving horizontal flow velocities using the techniques of solar granule tracking, dopplergrams, and time-distance helioseismology. Methods. Coherent structure tracking (CST) and time-distance helioseismology were used to investigate the solar differential rotation and meridional circulation at the solar surface on a 30-day HMI/SDO sequence. The influence of a large sunspot on these large-scale flows with a specific 7-day HMI/SDO sequence has been also studied. Results. The large-scale flows measured by the CST on the solar surface and the same flow determined from the same data with the helioseismology in the first 1 Mm below the surface are in good agreement in amplitude and direction. The torsional waves are also located at the same latitudes with amplitude of the same order. We are able to measure the meridional circulation correctly using the CST method with only 3 days of data and after averaging between +/-15 degrees in longitude. Conclusions. We conclude that the combination of CST and Doppler velocities allows us to detect properly the differential solar rotation and also smaller amplitude flows such as the meridional circulation and torsional waves. The results of our methods are in good agreement with helioseismic measurements.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10308 - Astronomy (including astrophysics,space science)

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2018

Kód důvěrnosti údajů

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

Název periodika

Astronomy &amp; Astrophysics [online]

ISSN

1432-0746

e-ISSN

—

Svazek periodika

611

Číslo periodika v rámci svazku

Neuveden

Stát vydavatele periodika

FR - Francouzská republika

Počet stran výsledku

9

Strana od-do

—

Kód UT WoS článku

000429194700001

EID výsledku v databázi Scopus

2-s2.0-85045214294