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arXiv · 2511.18067

B[e]-star CI Cam: a high-resolution spectrum atlas in the range of 395$\div$780 nm

Valentina G. Klochkova·Anatoly S. Miroshnichenko·Victoria N. Komarova·Nonna S. Tavolzhanskaya
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Abstract

The atlas of the spectrum of the B[e] star CI Cam obtained with the 6-meter BTA telescope in combination with the NES spectrograph in the wavelength interval of 395$\div$780 nm with a resolution of $\lambda/\Delta\lambda\ge60\,000$ is presented. The atlas contains about 400 spectral features and illustrates the diversity of spectral features of the unique star, forming in a complex circumstellar environment. The spectrum is dominated by forceful single-peaked HI, HeI emissions and numerous double-peaked permitted and forbidden emissions of ions of chemical elements starting from the CNO triad up to metals (Mg, Al, Ti, V, Cr, Fe) with practically ``rectangular'' profiles. The FeII and [FeII] emissions predominate in the spectrum. However, several other double-peaked forbidden ion emissions were also detected: [VII], [Cr II], [Ni II]. The atlas is presented graphically, with a separate figure corresponding to each echelle order. A list of identified lines, including a number of known interstellar features is presented in table form. CI Cam supergiant status has been confirmed.

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Valentina G. Klochkova, Anatoly S. Miroshnichenko, Victoria N. Komarova, Nonna S. Tavolzhanskaya. 2025-11-22. B[e]-star CI Cam: a high-resolution spectrum atlas in the range of 395$\div$780 nm. https://arxiv.org/abs/2511.18067

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