LZ Cephei
{{short description|Variable star in the constellation Cepheus}}
{{Starbox begin}}
{{Starbox image
| image = 250px
| caption = A light curve for LZ Cephei, plotted from TESS data
}}
{{Starbox observe
| epoch = J2000.0
| dec = {{DEC|+58|00|01.3098}}
| constell = Cepheus
}}
{{Starbox character
| class = O 9III (primary) + ON 9.7V (secondary)
| b-v =
| u-b =
| variable = Rotating ellipsoidal variable
}}
{{Starbox astrometry
| radial_v =
| prop_mo_ra = {{val|-3.096|0.061}}
| prop_mo_dec = {{val|-2.611|0.054}}
| parallax = 0.9070
| p_error = 0.0525
| absmag_v =
}}
{{Starbox orbit
| primary =
| name =
| period_unitless = {{val|3.070507|ul=days}}
| eccentricity = 0.0
| axis_unitless =
| inclination = {{val|49|2.4}}
| node =
| periastron =
| periarg =
| periarg_primary =
| k1 = {{val|88.72|1.02}}
| k2 = {{val|224.48|2.58}}
}}
{{Starbox detail
| component1 = Primary
| radius = {{val|11.7|3.3|2.7}}
| temperature = {{val|fmt=commas|32000|1000}}
| metal_fe =
| rotational_velocity =
| age_gyr =
| component2 = Secondary
| radius2 = {{val|9.4|2.6|2.2}}
| temperature2 = {{val|fmt=commas|28000|1000}}
| gravity2 = {{val|3.48|0.02}}
| rotational_velocity2 =
| age_gyr2 =
}}
{{Starbox catalog
| names = 14 Cephei, HD 209481, BD+57 2441, HIP 108772, HR 8406, SAO 33990
}}
{{Starbox reference
| Simbad = LZ+Cep
}}
{{Starbox end}}
LZ Cephei, also known by its Flamsteed designation 14 Cephei, is a star about 3,600 light years from the Earth, in the constellation Cepheus. Its apparent magnitude is 5.6, making it faintly visible to the naked eye of an observer far from city lights. The star is a rotating ellipsoidal variable whose brightness, as measured by the Hipparcos satellite, varies between magnitude 5.52 and 5.61.
LZ Cephei was discovered to be a binary star by William Edmund Harper in 1931.
The orbital elements were first calculated by Robert Methven Petrie in 1962. It was discovered to be a variable star in 1972 by N. Kameswara Rao, using the Lick Observatory's 24 inch telescope. The star was given the variable star designation LZ Cephei in 1973. It was classified as an ellipsoidal variable by Hill et al. in 1976.
A 2011 study of LZ Cephei concluded that the existing data are best explained if the system is a semi-detached binary with either the primary or secondary star nearly filling its Roche lobe. The secondary star, now less massive than the primary, was originally the more massive star, and matter has been transferred from the secondary to the primary.
References
{{Reflist|30em|refs=
| title=MAST: Barbara A. Mikulski Archive for Space Telescopes
| url=https://mast.stsci.edu/portal/Mashup/Clients/Mast/Portal.html
| publisher=Space Telescope Science Institute |access-date=14 January 2023}}
{{cite Gaia DR3|2199161386015469312}}
| last1=Harries | first1=T. J. | last2=Hilditch | first2=R. W. | last3=Hill | first3=G.
| title=Interacting OB star binaries: LZ Cep, SZ Cam and IU AUR
| journal=Monthly Notices of the Royal Astronomical Society
| date=April 1998 | volume=295 | issue=2 | pages=386–396
| doi=10.1046/j.1365-8711.1998.01340.x | bibcode=1998MNRAS.295..386H | doi-access=free }}
| bibcode=2017ARep...61...80S
| title=General catalogue of variable stars: Version GCVS 5.1
| last1=Samus' | first1=N. N. | last2=Kazarovets | first2=E. V. | last3=Durlevich | first3=O. V.
| last4=Kireeva | first4=N. N. | last5=Pastukhova | first5=E. N.
| journal=Astronomy Reports | year=2017 | volume=61 | issue=1 | page=80
| doi=10.1134/S1063772917010085 | s2cid=125853869 | doi-access=free }}
| title=14 Cep -- Spectroscopic Binary| access-date=2023-01-14}}
| last1=Kukarkin | first1=B. V. | last2=Kholopov | first2=P. N. | last3=Kukarkina | first3=N. P.
| title=59th Name-List of Variable Stars | journal=Information Bulletin on Variable Stars
| date=October 1973 | volume=834 | issue=1 | page=1 | bibcode=1973IBVS..834....1K | bibcode-access=free }}
| last1=Kameswara Rao | first1=N. | title=Light Variations of Three Spectroscopic Binaries
| journal=Publications of the Astronomical Society of the Pacific
| date=August 1972 | volume=84 | issue=500 | pages=563–565
| doi=10.1086/129332 | bibcode=1972PASP...84..563K | doi-access=free }}
| last1=Hill | first1=G. | last2=Hilditch | first2=R. W. | last3=Pfannenschmidt | first3=E. L.
| title=Photoelectric measures of variable stars observed at Mt. Kobau (1970 - 73)
| journal=Publications of the Dominion Astrophysical Observatory Victoria
| date=January 1976 | volume=15 | pages=1–35 | bibcode=1976PDAO...15....1H | bibcode-access=free }}
| last1=Petrie | first1=R. M.
| title=The O-type spectroscopic binary 14 Cephei
| journal=Publications of the Dominion Astrophysical Observatory Victoria
| date=May 1962 | volume=12 | pages=111–116 | bibcode=1962PDAO...12..111P | bibcode-access=free }}
| last1=Mahy | first1=L. | last2=Martins | first2=F. | last3=Machado | first3=C.
| last4=Donati | first4=J. F. | last5=Bouret | first5=J. C.
| title=The two components of the evolved massive binary LZ Cephei. Testing the effects of binarity on stellar evolution
| journal=Astronomy & Astrophysics | date=September 2011 | volume=533
| doi=10.1051/0004-6361/201116993 | arxiv=1106.6162 | bibcode=2011A&A...533A...9M | doi-access=free }}
}}
{{Stars of Cepheus}}
{{DEFAULTSORT:LZ Cephei}}
Category:Rotating ellipsoidal variables
Category:Cepheus (constellation)