Ongoing magnetospheric accretion in the multiring transitional disc of HD 141569A
Monthly Notices of the Royal Astronomical Society, cilt.551, sa.4, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 551 Sayı: 4
- Basım Tarihi: 2026
- Doi Numarası: 10.1093/mnras/stag1441
- Dergi Adı: Monthly Notices of the Royal Astronomical Society
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Aerospace Database, Applied Science & Technology Source, Compendex, INSPEC, zbMATH, Directory of Open Access Journals, Academic Search Ultimate (EBSCO), Technology Collection (ProQuest)
- Anahtar Kelimeler: circumstellar matter, stars: activity, stars: individual: HD 141569A, stars: pre-main sequence, stars: variables: T Tauri, Herbig Ae/Be
- Akdeniz Üniversitesi Adresli: Evet
Özet
We present the results of long-term spectroscopic monitoring of the Herbig Ae star HD 141569A. The analysis is based on spectra obtained at the Shamakhy Astrophysical Observatory during 2017–2023 together with archival Ultraviolet and Visual Echelle Spectrograph spectra acquired with the European Southern Observatory Very Large Telescope in 2007. Using synthetic model atmospheres, we investigated the emission structure of the hydrogen Balmer lines in the presence of strong photospheric absorption. The H (Formula presented) and H (Formula presented) emission profiles exhibit double-peaked structures with central depressions, indicating that the emitting gas is in Keplerian rotation within the circumstellar disc. Peak velocities were used to estimate the emission radii of several hydrogen lines. We find an increase in the linear gas velocity together with a gradual decrease in the peak intensity ratio ((Formula presented) ) from the outer to the inner disc regions. The Na i D, Ca ii K, and metallic absorption lines reveal outflowing gas with a velocity of approximately (Formula presented) km s(Formula presented). Their narrow widths, significantly smaller than the stellar rotational velocity, suggest formation within an optically thick circumstellar wind. The hydrogen, Na i, and He i (Formula presented) lines show spectroscopic signatures of ongoing accretion onto the star. Accretion rates derived from the H (Formula presented) and H (Formula presented) lines yield the most reliable lower limit to the mass accretion rate, (Formula presented). These findings demonstrate that magnetospheric accretion onto HD 141569A remains active despite its highly evolved multiring transitional disc.