Comparison of the times of maximum light by A. M. van Genderen in 1967 showed a variation in the period. This followed a sine wave with a period of 1,129 days.[17] In 1975, T. G. Barnes and T. J. Moffett confirmed the period variation and suggested it is being caused by a light-travel time effect in a single-lined spectroscopic binary with an orbital period of 3.14 years.[15] Radial velocity measurements by C. Bardin and M. Imbert in 1984 confirmed the binary nature of this system.[16] Updated orbital elements were published by T. J. Moffett and associates in 1988.[6]
This is a spectroscopic binary system with an orbital period of 3.2337 ± 0.0022 years and an eccentricity (ovalness) of 0.19.[6] A decrease in the longitude of the periapsis has been detected, which may indicate that the secondary component is actually a close binary.[7] The primary component is a Delta Scuti variable with a main pulsation frequency of 8.296943±0.000002 cycles per day. 23 frequencies have been identified, of which 14 are multiples of the main frequency. Models of the stellar properties suggest that it is near the end of its corehydrogen burning stage, or has just begun shell burning.[8] The secondary is likely a main sequence star with a class in the range F2 V – K3 V.[6]
^ abLi, Lin-Jia; Qian, Sheng-Bang (December 2013), "Observations and Orbital Analysis of the High-Amplitude Delta Scuti Star SZ Lyncis: The Unusual Orbital Precession", Publications of the Astronomical Society of Japan, 65 (6): 116, Bibcode:2013PASJ...65..116L, doi:10.1093/pasj/65.6.116, 116.
^ abcAdassuriya, J.; et al. (March 2021), "Asteroseismology of SZ Lyn using multiband high time resolution photometry from ground and space", Monthly Notices of the Royal Astronomical Society, 502 (1): 541–555, arXiv:2012.11940, Bibcode:2021MNRAS.502..541A, doi:10.1093/mnras/staa3923.
^Gazeas, K. D.; Niarchos, P. G. (July 2005), Sterken, C. (ed.), "The Light-Time Effect in SZ Lyn", The Light-Time Effect in Astrophysics, Proceedings of ASP Conference Series, Vol. 335, held in Brussels 19–22 July 2004, vol. 335, San Francisco: Astronomical Society of the Pacific, p. 297, Bibcode:2005ASPC..335..297G.
^ abBarnes, T. G., III; Moffett, T. J. (January 1975), "Photometric properties and evidence of duplicity for SZ Lyncis", Astronomical Journal, 80: 48–55, Bibcode:1975AJ.....80...48B, doi:10.1086/111712.{{citation}}: CS1 maint: multiple names: authors list (link)
^ abBardin, Cl.; Imbert, M. (August 1984), "Mouvement orbital de la céphéide naine SZ Lyn", Astronomy and Astrophysics Supplement Series (in French), 57: 249–252, Bibcode:1984A&AS...57..249B.
^van Genderen, A. M. (January 1967), "Variations in the period and in the light-curve of SZ Lyncis", Bulletin of the Astronomical Institutes of the Netherlands, 19: 74, Bibcode:1967BAN....19...74V.
Further reading
Ciocca, M. (June 2013), "BVRI Observations of SZ Lyncis at the EKU Observatory", The Journal of the American Association of Variable Star Observers, 41 (1): 134, Bibcode:2013JAVSO..41..134C.
Gazeas, K. D.; et al. (June 2004), "SZ Lyn: New pulsational and orbital elements based on old and recent photometric observations", Communications in Asteroseismology, 145: 49, Bibcode:2004CoAst.145...49G, doi:10.1553/cia145s47.
Gazeas, K. D.; et al. (June 2004), "SZ Lyn: New BVRI CCD observations and improved pulsational and orbital elements", Communications in Asteroseismology, 144: 26–34, Bibcode:2004CoAst.144...26G.
Soliman, M. A.; et al. (January 1986), "Photoelectric Observations of SZ Lyncis", Communications of the Konkoly Observatory, X, 2 (88): 39–56, Bibcode:1986CoKon..88...39S.
Jiang, S. -Y.; et al. (December 1985), "The photoelectric photometry of SZ Lyn and its period changes", Acta Astronomica Sinica, 26 (2): 135–143, Bibcode:1985AcASn..26..135J.
Garbuzov, G. A. (October 1983), "Spectroscopic Investigation of SZ Lyn and SS Psc", Information Bulletin on Variable Stars, 2417: 1, Bibcode:1983IBVS.2417....1G.
Bardin, C.; Imbert, M. (May 1981), "Vitesses radiales à haute résolution temporelle de la cépheïde naine SZ Lyn", Astronomy and Astrophysics (in French), 98: 198–202, Bibcode:1981A&A....98..198B.
Garbusov, G. A. (October 1980), "UBV Photometry of SZ Lyn", Information Bulletin on Variable Stars, 1854: 1, Bibcode:1980IBVS.1854....1G.
Hopp, U.; Witzigmann, S. (May 1979), "A B Light Curve of SZ Lyn", Information Bulletin on Variable Stars, 1597: 1, Bibcode:1979IBVS.1597....1H.
Garrido, R.; et al. (April 1979), "Photometry of the dwarf cepheids SZ Lyn and EH Lib", Astronomy and Astrophysics Supplement Series, 36: 51–56, Bibcode:1979A&AS...36...51G.
Africano, J. (April 1978), "Photoelectric Maximum of SZ Lyncis", Information Bulletin on Variable Stars, 1408: 1, Bibcode:1978IBVS.1408....1A.
Karetnikov, V. G.; Medvedev, Yu. A. (1978), "Photoelectric BV-Observations of the Variable Star SZ Lyncis", Peremennye Zvezdy, 21: 85, Bibcode:1978PZ.....21...85K.
Karetnikov, V. G.; Medvedev, Y. A. (July 1977), "Photoelectric Moments of Maxima of SZ Lyn", Information Bulletin on Variable Stars, 1309: 1, Bibcode:1977IBVS.1309....1K.
Duerbeck, H. W. (September 1976), "New B, V Light Curves of SZ Lyncis", Information Bulletin on Variable Stars, 1171: 1, Bibcode:1976IBVS.1171....1D.
McNamara, D. H.; Feltz, K. A. Jr. (April 1976), "Radial-velocity variations of SZ Lyncis and EH Librae", Publications of the Astronomical Society of the Pacific, 88: 164–167, Bibcode:1976PASP...88..164M, doi:10.1086/129919, S2CID117774965.
Wisse, Marijke; Wisse, P. N. J. (January 1969), "On the maximum of SZ Lyncis (Note)", Bulletin of the Astronomical Institutes of the Netherlands, 20: 333, Bibcode:1969BAN....20..333W.
Broglia, P. (December 1963), "The ultrashort period variable SZ Lyn", Memorie della Societa Astronomica Italiana, 34: 431, Bibcode:1963MmSAI..34..431B.
van Genderen, A. M. (March 1963), "Photo-electric observations in four colours of the ultra-short-period variable SZ Lyncis", Bulletin of the Astronomical Institutes of the Netherlands, 17: 243, Bibcode:1963BAN....17..243V.
Gefferth, K.; Szeidl, B. (March 1962), "SZ Lyncis", Information Bulletin on Variable Stars, 7: 2, Bibcode:1962IBVS....7....2G.
Notni, P. (March 1962), "The Period of SZ Lyncis", Information Bulletin on Variable Stars, 7: 3, Bibcode:1962IBVS....7....3N.