ACCRETION IN HERBIG AE/BE STARS: THE ROLE OF EMISSION LINES
F.S. Huseynova
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ABSTRACT

The paper analyzes whether the emission lines observed in Herbig Ae/Be stars are signs of accretion. The validity of each line as an accretion indicator is assessed by comparing the emission line detection rate with the UV-excess detection rate. It is confirmed that accretion indicators for CTTs, such as Hβ, Hα, Paβ and Brγ, are also valid accretion indicators in HAeBe stars. In addition, based on the low level of emission lines detected, it is determined that several other lines, such as [O I] λ6300 and He I 5876 Å, may be weak indicators. However, when these lines are detected, they are almost always associated with UV-excess.
The large number of objects and emission lines analyzed here provides robust relationships between accretion luminosity and line brightness for a wide wavelength range, which opens up new diagnostic possibilities for accretion in the J-band. These relationships provide a useful tool in future accretion studies for both HAeBes and CTTs. Finally, it is worth noting that when emission lines are detected in HAeBes, their luminosities always correlate with the accretion luminosity of the star.

Keywords: radiation lines, accretion, P Cyg profile, stellar wind.
DOI:10.70784/azip.2.2026106

Received: 26.01.2026
Internet publishing: 30.01.2026    AJP Fizika A 2026 01 az p.06-09

AUTHORS & AFFILIATIONS

Ministry of Science and Education of the Republic of Azerbaijan Batabat Astrophysical Observatory, Nakhchivan State University AZ7000, Azerbaijan, Nakhchivan
E-mail: faidahuseynova@gmail.com

Graphics and Images

       

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