2024
Unveiling stellar aurorae: simulating auroral emission lines in hot stars induced by high-energy irradiation
KAJAN, Michal; Jiří KRTIČKA a Jiří KUBÁTZákladní údaje
Originální název
Unveiling stellar aurorae: simulating auroral emission lines in hot stars induced by high-energy irradiation
Autoři
KAJAN, Michal (703 Slovensko, domácí); Jiří KRTIČKA (203 Česká republika, domácí) a Jiří KUBÁT (203 Česká republika)
Vydání
Monthly Notices of the Royal Astronomical Society, Oxford University Press, 2024, 0035-8711
Další údaje
Jazyk
angličtina
Typ výsledku
Článek v odborném periodiku
Obor
10308 Astronomy
Stát vydavatele
Velká Británie a Severní Irsko
Utajení
není předmětem státního či obchodního tajemství
Odkazy
Impakt faktor
Impact factor: 4.800 v roce 2023
Kód RIV
RIV/00216224:14310/24:00137715
Organizační jednotka
Přírodovědecká fakulta
UT WoS
001231710600006
EID Scopus
2-s2.0-85194484314
Klíčová slova anglicky
radiative transfer; software: simulations; stars: atmospheres; stars: early-type; stars: emission-line; Be; stars: magnetic fields
Štítky
Příznaky
Mezinárodní význam, Recenzováno
Změněno: 21. 11. 2024 11:17, Mgr. Marie Novosadová Šípková, DiS.
Anotace
V originále
Auroral emission lines result from the interaction between magnetic field and stellar wind, offering valuable insights into physical properties and processes occurring within magnetospheres of celestial bodies. While extensively studied in planetary and exoplanetary atmospheres, in ultracool dwarfs, and as radio emission from early-type stars, the presence of specific auroral emission lines in hot star spectra remains unexplored. In this study, we utilized tlusty code to simulate the auroral lines, while modelling the effect of the interaction between stellar wind and magnetosphere through X-ray irradiation. Utilizing high-resolution synthetic spectra generated from model atmospheres, we identified potential candidate lines indicative of auroral emission, which were absent in non-irradiated spectra. Emission lines in synthetic spectra were present primarily in the infrared domain. The most prominent line generated by irradiation was He ii 69458 & Aring;, which appeared in all our model atmospheres with effective temperatures ranging from 15 kK to 30 kK. We also calculated the minimum irradiation required to detect emission in this most prominent line. The presence of emission lines was interpreted by considering changes in the population of different excited states of given atoms. Besides the appearance of infrared emission lines, high-energy irradiation causes infrared excess. To complement our simulations, we also searched for auroral lines in Far Ultraviolet Spectroscopic Explorer (FUSE) observations, which are deposited in the Multimission Archive at Space Telescope catalogue. The comparison of observed spectra with synthetic spectra did not identify any possible candidate emission lines in FUSE spectra.