Singly Ionized Iridium Spectral Lines in the Atmosphere of Hot Stars

Zoran Simic´ *

Astronomical Observatory, Volgina 7, 11060 Belgrade, Serbia

Nenad M. Sakan

University of Belgrade, Institute of Physics, P.O.Box 57, 11001 Belgrade, Serbia.

Nenad Milovanovic

Astronomical Observatory, Volgina 7, 11060 Belgrade, Serbia

Mihailo Martinovic

Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721, USA and LESIA, Observatoire de Paris, Meudon, France.

*Author to whom correspondence should be addressed.


Abstract

The electron-impact broadening parameters of ion lines are of interest for a number of problems in astrophysical, laboratory, and technological plasma investigations. Singly ionized Iridium lines are confirmed their presence in stellar spectra of the chemically peculiar stars. Our calculations are performed using the modified semiempirical method of Dimitrijevic and Konjevi ´ c. Stark widths for ´ 301 Ir II spectral lines are presented. From the calculated list of lines, the 21 strongest lines from the iridium spectrum are selected with high value of intensity ≥ 3000 to demonstrate importance of the Stark broadening mechanism for different types of stars. The analysis of the electron-impact effect on spectral line shapes are performed and obtained Stark and Doppler withds are compared.

Keywords: Atomic data, lines, plasmas


How to Cite

Simic´, Z., Sakan, N. M., Milovanovic, N., & Martinovic, M. (2021). Singly Ionized Iridium Spectral Lines in the Atmosphere of Hot Stars. International Astronomy and Astrophysics Research Journal, 3(1), 86–100. Retrieved from https://www.journaliaarj.com/index.php/IAARJ/article/view/41

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