Covariations of chromospheric and photometric variability of the young Sun analogue HD 30495: evidence for and interpretation of mid-term periodicities

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985530%3A_____%2F19%3A00497495" target="_blank" >RIV/67985530:_____/19:00497495 - isvavai.cz</a>

Výsledek na webu

<a href="https://academic.oup.com/mnras/article/483/2/2748/5228758" target="_blank" >https://academic.oup.com/mnras/article/483/2/2748/5228758</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1093/mnras/sty3290" target="_blank" >10.1093/mnras/sty3290</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Covariations of chromospheric and photometric variability of the young Sun analogue HD 30495: evidence for and interpretation of mid-term periodicities

Popis výsledku v původním jazyce

This study reports the synchronization between the chromospheric and photometric variability at time-scale of about 1.6-1.8 yr as observed for the young, rapidly rotating solar analogue HD 30495. In addition, HD 30495 may be presenting evidence of surface differential rotation at time-scales of about 11 d and 21 d, as well as the sunspot-like decadal cycles at 11-12 yr or so. We apply a new gapped wavelet method of time-frequency analysis for studying the variability in a new composite of the chromospheric S-index (1967-2018) and the longest photometric Delta(b + y)/2 index (1993-2018). We discuss and interpret our results in relation to other observed mid-term periodicities roughly of the same time-scales that had been found recently from not only chromospheric and photospheric activity indices but also from coronal X-ray emissions as observed in a considerably large set of stellar samples including those young Sun analogues from the Kepler satellite project. Thus, there is an apparent universality of such mid-term activity modulation time-scales as this solar-stellar magnetic phenomenon is well observed directly for a host of solar activity related indices covering the photopsheric, chromospheric, coronal, and even the heliospheric (utilizing the measures of incoming galactic cosmic rays as a probe of activity variations) activity records. This is why we made a further attempt to interpret the results in search of a realistic generation mechanism as well as spatio-temporal persistency of the phenomenon under a wide scenario of dynamo simulations.

Název v anglickém jazyce

Covariations of chromospheric and photometric variability of the young Sun analogue HD 30495: evidence for and interpretation of mid-term periodicities

Popis výsledku anglicky

This study reports the synchronization between the chromospheric and photometric variability at time-scale of about 1.6-1.8 yr as observed for the young, rapidly rotating solar analogue HD 30495. In addition, HD 30495 may be presenting evidence of surface differential rotation at time-scales of about 11 d and 21 d, as well as the sunspot-like decadal cycles at 11-12 yr or so. We apply a new gapped wavelet method of time-frequency analysis for studying the variability in a new composite of the chromospheric S-index (1967-2018) and the longest photometric Delta(b + y)/2 index (1993-2018). We discuss and interpret our results in relation to other observed mid-term periodicities roughly of the same time-scales that had been found recently from not only chromospheric and photospheric activity indices but also from coronal X-ray emissions as observed in a considerably large set of stellar samples including those young Sun analogues from the Kepler satellite project. Thus, there is an apparent universality of such mid-term activity modulation time-scales as this solar-stellar magnetic phenomenon is well observed directly for a host of solar activity related indices covering the photopsheric, chromospheric, coronal, and even the heliospheric (utilizing the measures of incoming galactic cosmic rays as a probe of activity variations) activity records. This is why we made a further attempt to interpret the results in search of a realistic generation mechanism as well as spatio-temporal persistency of the phenomenon under a wide scenario of dynamo simulations.

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

2019

Kód důvěrnosti údajů

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

Název periodika

Monthly Notices of the Royal Astronomical Society

ISSN

0035-8711

e-ISSN

—

Svazek periodika

483

Číslo periodika v rámci svazku

2

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

10

Strana od-do

2748-2757

Kód UT WoS článku

000462258200098

EID výsledku v databázi Scopus

2-s2.0-85065209532