CP Boötis

{{Short description|Star in the constellation Boötes}} {{Starbox begin }} {{Starbox observe | epoch = J2000 | constell = [[Boötes]] | ra = {{RA|14|33|20.26330}}<ref name=GaiaDR2/> | dec = {{DEC|+36|57|32.4483}}<ref name=GaiaDR2/> | appmag_v = 6.40<ref name=Karatas2006/> }} {{Starbox character | type = subgiant<ref name=lebre1999/> | class = F8 IVw<ref name=Barry1970/> | b-v = 0.51<ref name=Karatas2006/> | u-b = 0.07<ref name=Karatas2006/> | variable = [[Delta Scuti variable|δ Sct]]<ref name=gcvs/> }} {{Starbox astrometry | radial_v = +5.9<ref name=Casagrande2011/> | prop_mo_ra = +2.694<ref name=GaiaDR2/> | prop_mo_dec = −73.096<ref name=GaiaDR2/> | parallax = 12.9135 | p_error = 0.0244 | parallax_footnote = <ref name=GaiaDR2/> | absmag_v = 2.05<ref name=Karatas2006/> }} {{Starbox detail | mass = 1.77<ref name=Casagrande2011/> | radius = | luminosity = {{Val|12.0|1.5|1.3}}<ref name=doNascimento2000/> | gravity = 3.67<ref name=Casagrande2011/> | temperature = 6,276<ref name=Casagrande2011/> | metal_fe = 0.25<ref name=Casagrande2011/> | rotational_velocity = 5.7<ref name=lebre1999/> | age_gyr = 1.70<ref name=Casagrande2011/> }} {{Starbox catalog | names={{odlist | V=CP Boo | BD=+37°2545 | FK5= | HD=127986 | HIP=71168 | HR=5441 | SAO=64212 | AAVSO=1429+37 }}<ref name=SIMBAD/> }} {{Starbox reference | Simbad = HD+127986 }} {{Starbox end}}

'''CP Boötis''' is a yellow-white hued [[star]] in the northern [[constellation]] of [[Boötes]]. With a baseline [[apparent visual magnitude]] of 6.40,<ref name=Karatas2006/> it is at or near the lower limit for visibility with the typical [[naked eye]] in good viewing conditions. The distance to this star can be estimated from its annual [[stellar parallax|parallax shift]] of {{Val|12.91|ul=mas}},<ref name=GaiaDR2/> which yields a range of 252.6 [[light year]]s. It is moving further away with a heliocentric [[radial velocity]] of +5.9 km/s.<ref name=Casagrande2011/>

In May of 1977, Michel Auvergne ''et al.'' inadvertently discovered that the star is a [[variable star]], when they used it as a comparison star for photometric observations of [[gamma Boötis]].<ref name="Auvergne1977"/> It was given its [[variable star designation]], CP Boötis, in 1981.<ref name="Kholopov1981"/>

This is an [[F-type star|F-type]] [[subgiant star]] with a [[stellar classification]] of F8 IVw,<ref name=Barry1970/> which indicates it has nearly consumed the hydrogen at its core and is now [[stellar evolution|evolving]] into a [[giant star]]. It is a low amplitude [[Delta Scuti variable]]<ref name=Galeev2012/> that varies by 0.02 magnitude.<ref name=AAVSOBP/> At the age of 1.7<ref name=Casagrande2011/> billion years it is spinning with a [[projected rotational velocity]] of 5.7 km/s.<ref name=lebre1999/> The star has 1.77<ref name=Casagrande2011/> times the [[mass of the Sun]] and is radiating 12<ref name=doNascimento2000/> times the [[Sun's luminosity]] from its [[photosphere]] at an [[effective temperature]] of 6,276 K.<ref name=Casagrande2011/>

==References== <references> <ref name=SIMBAD>{{cite simbad | title=HD 127986 | access-date=23 August 2018 }}</ref>

<ref name="Auvergne1977">{{cite journal | last1=Auvergne | first1=M. | last2=Le Contel | first2=J. M. | last3=Sareyan | first3=J. P. | last4=Valtier | first4=J. C. | last5=Daguillon | first5=J. | title=Observations of the Star gamma Bootis and of the New Variable Star HR 5441 | journal=Information Bulletin on Variable Stars |date=November 1977 | bibcode=1977IBVS.1365....1A | volume=1365 | url=https://ibvs.konkoly.hu/pub/ibvs/1301/1365.pdf | access-date=5 December 2024}}</ref>

<ref name="Kholopov1981">{{cite journal | last1=Kholopov | first1=P. N. | last2=Samus | first2=N. N. | last3=Kukarkina | first3=N. P. | last4=Medvedeva | first4=G. I. | last5=Perova | first5=N. B. | title=65th Name-List of Variable Stars | journal=Information Bulletin on Variable Stars | date=February 1981 | volume=1921 | pages=1–21 | bibcode=1981IBVS.1921....1K | url=https://ibvs.konkoly.hu/pub/ibvs/1901/1921.pdf | access-date=5 December 2024}}</ref>

<ref name=gcvs>{{citation | 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 | volume=61 | pages=80–88 | year=2017 | issue=1 | postscript=. | doi=10.1134/S1063772917010085 | bibcode=2017ARep...61...80S | s2cid=125853869 }}<br>See: [http://webviz.u-strasbg.fr/viz-bin/VizieR-S?V*%20CP%20Boo CP Boo]</ref>

<ref name=AAVSOBP>{{citation | postscript=. | title=CP Boötis | last1=Watson | first1=Christopher | date=January 4, 2010 | work=AAVSO Website | publisher=[[American Association of Variable Star Observers]] | url=http://www.aavso.org/vsx/index.php?view=detail.top&oid=4419 | accessdate=3 August 2014}}</ref>

<ref name=Casagrande2011>{{citation | display-authors=1 | last1=Casagrande | first1=L. | last2=Schönrich | first2=R. | last3=Asplund | first3=M. | last4=Cassisi | first4=S. | last5=Ramírez | first5=I. | last6=Meléndez | first6=J. | last7=Bensby | first7=T. | last8=Feltzing | first8=S. | title=New constraints on the chemical evolution of the solar neighbourhood and Galactic disc(s). Improved astrophysical parameters for the Geneva-Copenhagen Survey | journal=Astronomy and Astrophysics | volume=530 | page=A138 | date=June 2011 | doi=10.1051/0004-6361/201016276 | arxiv=1103.4651 | bibcode=2011A&A...530A.138C | s2cid=56118016 | postscript=. }}</ref>

<ref name=doNascimento2000>{{citation | title=Lithium and rotation on the subgiant branch. II. Theoretical analysis of observations | display-authors=1 | last1=do Nascimento | first1=J. D. Jr. | last2=Charbonnel | first2=C. | last3=Lèbre | first3=A. | last4=de Laverny | first4=P. | last5=De Medeiros | first5=J. R. | journal=Astronomy and Astrophysics | postscript=. | volume=357 | pages=931–937 | date=May 2000 | bibcode=2000A&A...357..931D | arxiv=astro-ph/0003010 }}</ref>

<ref name=Galeev2012>{{citation | title=Chemical composition of δ Scuti stars: 1. AO CVn, CP Boo, KW Aur | last1=Galeev | first1=A. I. | last2=Ivanova | first2=D. V. | last3=Shimansky | first3=V. V. | last4=Bikmaev | first4=I. F. | journal=Astronomy Reports | display-authors=1 | volume=56 | issue=11 | pages=850–866 | date=November 2012 | doi=10.1134/S1063772912110029 | bibcode=2012ARep...56..850G | s2cid=124127339 }}</ref>

<ref name=Karatas2006>{{citation | last1=Karatas | first1=Y. | last2=Schuster | first2=W. J. | title=Metallicity and absolute magnitude calibrations for UBV photometry | journal=Monthly Notices of the Royal Astronomical Society | volume=371 | issue=4 | pages=1793–1812 | date=October 2006 | bibcode=2006MNRAS.371.1793K | doi=10.1111/j.1365-2966.2006.10800.x | postscript=. | doi-access=free }}</ref>

<ref name=lebre1999>{{citation | title=Lithium and rotation on the subgiant branch. I. Observations and spectral analysis | journal=Astronomy and Astrophysics | display-authors=1 | last1=Lèbre | first1=A. | last2=De Laverny | first2=P. | last3=De Medeiros | first3=J. R. | last4=Charbonnel | first4=C. | last5=Da Silva | first5=L. | volume=345 | pages=936 | year=1999 | bibcode=1999A&A...345..936L | postscript=. }}</ref>

<ref name=Barry1970>{{citation | title=Spectral classification of A & F stars | last1=Barry | first1=Don C. | journal=Astrophysical Journal Supplement | volume=19 | pages=281 | date=January 1970 | doi=10.1086/190209 | bibcode=1970ApJS...19..281B }}</ref> </references>

==External links== * [http://webviz.u-strasbg.fr/viz-bin/VizieR-S?HR%205441 HR 5441]

[[Category:F-type subgiants]] [[Category:Delta Scuti variables]]  [[Category:Boötes]] [[Category:Durchmusterung objects|BD+37 2545]] [[Category:Henry Draper Catalogue objects|127986]] [[Category:Hipparcos objects|071168]] [[Category:Bright Star Catalogue objects|5441]] [[Category:Objects with variable star designations|Bootis, CP]]