Analysis of the stellar occultations during the unprecedented long-duration flare

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985815%3A_____%2F24%3A00597853" target="_blank" >RIV/67985815:_____/24:00597853 - isvavai.cz</a>

Výsledek na webu

<a href="https://hdl.handle.net/11104/0355698" target="_blank" >https://hdl.handle.net/11104/0355698</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.3847/2041-8213/ad6c06" target="_blank" >10.3847/2041-8213/ad6c06</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Analysis of the stellar occultations during the unprecedented long-duration flare

Popis výsledku v původním jazyce

In strong stellar and solar flares, flare loops typically appear during the decay phase, providing an additional contribution to the flare emission and, possibly, obscuring the flare emission. Superflares, common in active, cool stars, persist mostly from minutes to several hours and alter the star's luminosity across the electromagnetic spectrum. Recent observations of a young main-sequence star reveal a distinctive cool loop arcade forming above the flaring region during a 27 hr superflare event, obscuring the region multiple times. Analysis of these occultations enables the estimation of the arcade's geometry and physical properties. The arcade's size expanded from 0.213 to 0.391 R * at a speed of approximately 3.5 km s-1. The covering structure exhibited a thickness below 12,200 km, with electron densities ranging from 1013 to 1014 cm-3 and temperatures below 7600 K, 6400 K, and 5077 K for successive occultations. Additionally, the flare's maximum emission temperature has to exceed 12,000 K for the occultations to appear. Comparing these parameters with known values from other stars and the Sun suggests the structure's nature as an arcade of cool flare loops. For the first time, we present the physical parameters and the reconstructed geometry of the cool flare loops that obscure the flaring region during the gradual phase of a long-duration flare on a star other than the Sun.

Název v anglickém jazyce

Analysis of the stellar occultations during the unprecedented long-duration flare

Popis výsledku anglicky

In strong stellar and solar flares, flare loops typically appear during the decay phase, providing an additional contribution to the flare emission and, possibly, obscuring the flare emission. Superflares, common in active, cool stars, persist mostly from minutes to several hours and alter the star's luminosity across the electromagnetic spectrum. Recent observations of a young main-sequence star reveal a distinctive cool loop arcade forming above the flaring region during a 27 hr superflare event, obscuring the region multiple times. Analysis of these occultations enables the estimation of the arcade's geometry and physical properties. The arcade's size expanded from 0.213 to 0.391 R * at a speed of approximately 3.5 km s-1. The covering structure exhibited a thickness below 12,200 km, with electron densities ranging from 1013 to 1014 cm-3 and temperatures below 7600 K, 6400 K, and 5077 K for successive occultations. Additionally, the flare's maximum emission temperature has to exceed 12,000 K for the occultations to appear. Comparing these parameters with known values from other stars and the Sun suggests the structure's nature as an arcade of cool flare loops. For the first time, we present the physical parameters and the reconstructed geometry of the cool flare loops that obscure the flaring region during the gradual phase of a long-duration flare on a star other than the Sun.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10308 - Astronomy (including astrophysics,space science)

Projekt

<a href="/cs/project/GF22-30516K" target="_blank" >GF22-30516K: Supererupce: Jejich původ a spojitost s planetami</a><br>

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2024

Kód důvěrnosti údajů

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

Název periodika

Astrophysical Journal Letters

ISSN

2041-8205

e-ISSN

2041-8213

Svazek periodika

972

Číslo periodika v rámci svazku

1

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

9

Strana od-do

L11

Kód UT WoS článku

001297491700001

EID výsledku v databázi Scopus

2-s2.0-85202495878