48 Persei

48 Persei (also known as c Persei, 48 Per, HR 1273, HIP 19343, or HD 25940) is a Be star in the constellation Perseus, approximately the 500th brightest of the visible stars in apparent magnitude. It is "well known for its complex spectrum and for its light and velocity variations". The name "48 Persei" is a Flamsteed designation given to it by John Flamsteed in his catalogue, published in 1712.

48 Persei is classified as a Gamma Cassiopeiae variable, and it has been given the variable star designation MX Persei. The star's brightness varies by 0.09 magnitudes in visible light. Koen and Eyer examined the Hipparcos data for this star, and found it varied with a period of 5.0569 days.

As a Be star, it is hot and blue, spinning so rapidly that it forms an unstable equatorial disk of matter surrounding it. Its mass has been estimated as seven times that of the Sun, and its estimated age of 40 million years makes it much younger than the Sun. In another few million years it will likely cease hydrogen fusion, expand, and brighten as it becomes a red giant.

A 1989 study proposed 48 Persei to be a single-lined spectroscopic binary with a period of 16.6 days, but subsequent studies, including close imaging surveys, have not confirmed this result. Hutter et al. (2021) consider it to be a single star.

References

Further reading

• Jackisch, G. (1963), "Photoelectric and Spectroscopic Observations of 48 Persei and 53 Persei", Information Bulletin on Variable Stars, 40: 1, Bibcode:1963IBVS...40....1J.
• Baliunas, S. D.; Ciccone, M. A.; Guinan, E. F.; Miskinis, P. (1975), "Photoelectric Study of the Bright Be Stars γ Cas, 48 Per, ψ Per, and φ Per.", Bulletin of the American Astronomical Society, 7: 252, Bibcode:1975BAAS....7Q.252B.
• Goraya, P. S. (1985), "Recent changes in the spectrum of the Be star 48 Persei", Astrophysics and Space Science, 109 (2): 373–380, Bibcode:1985Ap&SS.109..373G, doi:10.1007/BF00651283, S2CID 121525902.
• Tur, N. S.; Goraya, P. S.; Chaubey, U. S. (1987), "Continuum energy dissipation of 48 Persei", Astrophysics and Space Science, 139 (2): 257–262, Bibcode:1987Ap&SS.139..257T, doi:10.1007/BF00644354, S2CID 123262029.
• Guo, Xiao-Zhen; Guo, Zi-He; Hao, Jin-Xin (1991), "A study of the low dispersion spectrum and photometry of the Be star 48 Per in 1989", Acta Astronomica Sinica, 32 (4): 415–420, Bibcode:1991AcASn..32..415G.
• Hao, Jinxin; Lin, Huang; Catala, C.; Foing, B. H. (1995), "Nonradial pulsations in 48 Persei: results from MUSICOS 1989 campaign", Multi-site Continuous Spectroscopy. Proceedings of the 4th Workshop Held in Beijing, China, June 19–24, 1994: 91, Bibcode:1995mscs.conf...91H.
• Hubert, A. M.; Floquet, M.; Hao, J. X.; et al. (1997), "Multi-site continuous spectroscopy. V. Rapid photospheric variability in the Be star 48 Persei from the MUSICOS 1989 campaign", Astronomy & Astrophysics, 324: 929–940, Bibcode:1997A&A...324..929H.
• Delaa, O.; Stee, Ph.; Meilland, A.; et al. (2011), "Kinematics and geometrical study of the Be stars 48 Persei and ψ Persei with the VEGA/CHARA interferometer", Astronomy & Astrophysics, 529: A87, Bibcode:2011A&A...529A..87D, doi:10.1051/0004-6361/201015639.