View source for Astronomy:HR 5401

{{Short description|Possible astrometric binary system in the constellation Lupus}}
{{Starbox begin 
 | name = HR 5401
}}
{{Starbox observe
 | epoch = J2000 
 | constell = [[Astronomy:Lupus (constellation)|Lupus]]
 | ra = {{RA|14|27|12.18204}}<ref name=GaiaDR2/>
 | dec = {{DEC|−46|08|58.1316}}<ref name=GaiaDR2/>
 | appmag_v = 5.83<ref name=Anderson2012/>
}}
{{Starbox character 
 | class = A1m&nbsp;A5/7-F2<ref name=houk1978/>
 | b-v = {{Val|0.311|0.004}}<ref name=Anderson2012/>
}}
{{Starbox astrometry
 | radial_v = {{Val|−30.0|3.8}}<ref name=deBruijne2012/>
 | prop_mo_ra = −168.816<ref name=GaiaDR2/>
 | prop_mo_dec = −82.297<ref name=GaiaDR2/>
 | parallax = 15.8815
 | p_error = 0.2813
 | parallax_footnote = <ref name=GaiaDR2/>
 | absmag_v = 2.01<ref name=Anderson2012/>
}}
{{Starbox detail
 | source = 
 | mass = 
 | radius = 
 | luminosity = 13.01<ref name=Anderson2012/>
 | gravity = 3.92<ref name=North1994/>
 | temperature = 7,300<ref name=North1994/>
 | metal_fe = 0.2<ref name=North1994/>
 | rotational_velocity = 
 | age_myr = 
}}
{{Starbox catalog
 | names={{odlist | CD=−45° 9188 | HD=126504 | HIP=70663 | HR=5401 | SAO=224929 | WDS= WDS J14272-4608A }}<ref name=SIMBAD/>
}}
{{Starbox reference
| Simbad = HD+126504
}}
{{Starbox end}}

'''HR 5401''' is a possible [[Astronomy:Astrometric binary|astrometric binary]]<ref name=Eggleton2008/> [[Astronomy:Star|star]] system in the southern [[Astronomy:Constellation|constellation]] of [[Astronomy:Lupus (constellation)|Lupus]]. With an [[Astronomy:Apparent visual magnitude|apparent visual magnitude]] of 5.83,<ref name=Anderson2012/> it is just visible to the naked eye under good seeing conditions. The distance to HR 5401 can be estimated from its annual [[Astronomy:Stellar parallax|parallax shift]] of {{Val|15.9|ul=mas}},<ref name=GaiaDR2/> yielding a range of 205&nbsp;[[Light year|light year]]s. It is moving closer to Earth with a heliocentric [[Astronomy:Radial velocity|radial velocity]] of −30&nbsp;km/s,<ref name=deBruijne2012/> and is expected to come within {{Convert|49.43|pc|ly|abbr=on|disp=out|sigfig=3}} in ~524,000&nbsp;years.<ref name=Anderson2012/>

This is an [[Astronomy:Am star|Am star]]<ref name=Schroeder2007/> with a [[Astronomy:Stellar classification|stellar classification]] of A1m&nbsp;A5/7-F2.<ref name=houk1978/> Lu (1991) lists it as a likely dwarf [[Astronomy:Barium star|barium star]].<ref name=lu1991/> It is radiating 13<ref name=Anderson2012/> times the Sun's luminosity from its [[Astronomy:Photosphere|photosphere]] at an [[Astronomy:Effective temperature|effective temperature]] of 7,300&nbsp;K.<ref name=North1994/> This system is a source of [[Astronomy:X-ray astronomy|X-ray emission]] which may be coming from the companion.<ref name=Schroeder2007/>

HR 5401 has two visual companions. Component B is a magnitude 11.50 star at an angular separation of {{Val|33.1|ul=arcsecond}} along a [[Astronomy:Position angle|position angle]] (PA) of 114°, as of 1999. The second companion, designated component C, is magnitude 11.16 with a separation of {{Val|27.20|u=arcsecond}} at a PA of 164°, as of 2000.<ref name=wds2006/>

==References==
{{reflist|refs=

<ref name=SIMBAD>{{cite simbad | title=HD 126504 | access-date=2018-07-30 }}</ref>

<ref name=GaiaDR2>{{cite DR2}}</ref>

<ref name=Anderson2012>{{citation
 | title=XHIP: An extended hipparcos compilation
 | last1=Anderson | first1=E. | last2=Francis | first2=Ch.
 | journal=Astronomy Letters
 | volume=38 | issue=5 | pages=331 | year=2012
 | bibcode=2012AstL...38..331A | doi=10.1134/S1063773712050015
 | arxiv=1108.4971 | s2cid=119257644 | postscript=. }}</ref>

<ref name=lu1991>{{citation | postscript=.
 | title=Taxonomy of barium stars
 | last1=Lu | first1=Phillip K.
 | journal=Astronomical Journal
 | volume=101 | pages=2229 | year=1991
 | bibcode=1991AJ....101.2229L | doi=10.1086/115845 | doi-access=free}}</ref>

<ref name=houk1978>{{citation
 | last1=Houk | first1=Nancy
 | title=Michigan catalogue of two-dimensional spectral types for the HD stars
 | volume=2 | publication-place=Ann Arbor | year=1978
 | publisher=Dept. of Astronomy, University of Michigan
 | bibcode=1978mcts.book.....H | postscript=. }}</ref>

<ref name=Eggleton2008>{{citation
 | title=A catalogue of multiplicity among bright stellar systems
 | last1=Eggleton | first1=P. P. | last2=Tokovinin | first2=A. A.
 | journal=Monthly Notices of the Royal Astronomical Society
 | volume=389 | issue=2 | pages=869 | date=2008
 | doi=10.1111/j.1365-2966.2008.13596.x | arxiv=0806.2878
 | bibcode=2008MNRAS.389..869E | s2cid=14878976 | postscript=. }}</ref>

<ref name=North1994>{{citation
 | display-authors=1 | last1=North | first1=P.
 | last2=Berthet | first2=S. | last3=Lanz | first3=T.
 | title=The nature of the F STR lambda 4077 stars. 3: Spectroscopy of the barium dwarfs and other CP stars
 | journal=Astronomy and Astrophysics
 | volume=281 | issue=3 | pages=775–796 | date=January 1994
 | bibcode=1994A&A...281..775N | postscript=. }}</ref>

<ref name=Schroeder2007>{{citation
 | last1=Schröder | first1=C. | last2=Schmitt | first2=J. H. M. M.
 | title=X-ray emission from A-type stars
 | journal=Astronomy and Astrophysics | postscript=.
 | volume=475 | issue=2 | pages=677–684 | date=November 2007
 | doi=10.1051/0004-6361:20077429 | bibcode=2007A&A...475..677S | doi-access=free }}</ref>

<ref name=deBruijne2012>{{citation
 | last1=de Bruijne | first1=J. H. J. | last2=Eilers | first2=A.-C. 
 | title=Radial velocities for the HIPPARCOS-Gaia Hundred-Thousand-Proper-Motion project 
 | journal=Astronomy & Astrophysics
 | volume=546 | id=A61 | pages=14 | date=October 2012
 | doi=10.1051/0004-6361/201219219 | bibcode=2012A&A...546A..61D 
 | arxiv=1208.3048 | s2cid=59451347 | postscript=. }}</ref>

<ref name=wds2006>{{citation
 | display-authors=1 | last1=Mason | first1=B. D.
 | last2=Wycoff | first2=G. L. I. | last3=Hartkopf | first3=W. I.
 | date=2008 | title=Washington Visual Double Star Catalog, 2006.5 (WDS)
 | journal=The Astronomical Journal | volume=122 | issue=6 | page=3466 | bibcode=2001AJ....122.3466M | postscript=.
 | publisher=U. S. Naval Observatory, Washington D.C. | doi=10.1086/323920 | doi-access=free }}</ref>

}}

{{Stars of Lupus}}

[[Category:Am stars]]
[[Category:Astrometric binaries]]
[[Category:Lupus (constellation)]]
[[Category:Durchmusterung objects]]
[[Category:Henry Draper Catalogue objects|126504]]
[[Category:Hipparcos objects|070663]]
[[Category:Bright Star Catalogue objects|5401]]

{{Sourceattribution|HR 5401}}