Epsilon Canis Minoris
{{Short description|Suspected binary star system in the constellation Canis Minor}}
{{Starbox begin
| name = ε Canis Minoris
}}
{{Starbox image
| image=
{{Location mark
|image=Canis Minor constellation map.svg|alt=|float=center|width=220
|label=|position=right
|mark=Red circle.svg|mark_width=8|mark_link=ε Canis Minoris
|x=536|y=596
}}
|caption=Location of ε Canis Minoris (circled)
}}
{{Starbox observe
| epoch = J2000.0
| constell = Canis Minor
| dec = {{DEC|+09|16|33.9541}}
}}
{{Starbox character
| variable =
}}
{{Starbox astrometry
| prop_mo_dec = −8.497 ± 0.310
| parallax = 4.2624
| p_error = 0.2288
| parallax_footnote = {{cite DR2|3155451625572457344}}
}}
{{Starbox detail
| mass = {{Val|4.63|0.17}}
| radius = {{Val|45.51|4.34}}
| luminosity = {{Val|1086.5|197.8|fmt=commas}}
| temperature = {{Val|4916|70|fmt=commas}}
| gravity = {{Val|1.81|0.06}}
| metal_fe = {{Val|−0.12|0.10}}
| age_myr = {{Val|140|10}}
}}
{{Starbox catalog
| names = {{odlist | B=ε CMi | F=2 CMi | BD=+09°1643 | HD=58367 | HIP=36041 | HR=2828 | SAO=115425 | GC=9908 }}
}}
{{Starbox reference
| Simbad = eps+CMi
}}
{{Starbox end}}
Epsilon Canis Minoris (ε Canis Minoris) is a suspected binary star system in the equatorial constellation of Canis Minor. It is a fifth magnitude star, which means it is bright enough to be faintly visible to the naked eye. Based upon an annual parallax shift of just 3.13 mas as seen from Earth, this star is located roughly 770 light years from the Sun, give or take a 40 light year margin of error.
This is an evolved G-type bright giant star with a stellar classification of G6.5 IIb. It is most likely (99% chance) on the horizontal branch, and is a barium star that shows an abnormal overabundance of barium in its spectrum. This s-process element may have been accreted from a now white dwarf companion during a previous stage of its evolution. The bright giant component has an estimated 4.63 times the mass of the Sun and has expanded to 45.5 times the Sun's radius. The star is radiating 1,087 times the Sun's luminosity from its enlarged photosphere at an effective temperature of about 4,916 K.
References
{{reflist|refs=
| title=Validation of the new Hipparcos reduction
| last1=van Leeuwen | first1=F.
| journal=Astronomy and Astrophysics
| volume=474 | issue=2 | pages=653–664 | date=2007
| arxiv=0708.1752 | bibcode=2007A&A...474..653V
| doi=10.1051/0004-6361:20078357 | s2cid=18759600 | postscript=. }}
| title=Stellar compositions from narrow-band photometry - V. Barium abundances for 200 evolved stars
| last1=Williams | first1=P. M. | postscript=.
| journal=Monthly Notices of the Royal Astronomical Society
| volume=170 | pages=343–362 | date=February 1975
| issue=2 | doi=10.1093/mnras/170.2.343 | bibcode=1975MNRAS.170..343W | doi-access=free }}
| last1=Eggleton | first1=P. P. | last2=Tokovinin | first2=A. A.
| title=A catalogue of multiplicity among bright stellar systems
| journal=Monthly Notices of the Royal Astronomical Society
| volume=389 | issue=2 | pages=869–879 | date=September 2008
| doi=10.1111/j.1365-2966.2008.13596.x | doi-access=free | bibcode=2008MNRAS.389..869E
| arxiv=0806.2878 | s2cid=14878976 | postscript=. }}
| last1=Bernacca | first1=P. L. | last2=Perinotto | first2=M.
| title=A catalogue of stellar rotational velocities
| journal=Contributi Osservatorio Astronomico di Padova in Asiago
| volume=239 | issue=1 | year=1970
| page=1 | bibcode=1970CoAsi.239....1B | postscript=. }}
| display-authors=1 | last1=Takeda | first1=Yoichi
| last2=Sato | first2=Bun'ei | last3=Murata | first3=Daisuke
| title=Stellar Parameters and Elemental Abundances of Late-G Giants
| journal=Publications of the Astronomical Society of Japan
| date=August 2008 | volume=60 | issue=4 | pages=781–802
| bibcode=2008PASJ...60..781T | arxiv = 0805.2434
| doi=10.1093/pasj/60.4.781 | postscript=. }}
| 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=. }}
| title=Precise radial velocities of giant stars. VII. Occurrence rate of giant extrasolar planets as a function of mass and metallicity
| display-authors=1 | last1=Reffert | first1=Sabine
| last2=Bergmann | first2=Christoph | last3=Quirrenbach | first3=Andreas
| last4=Trifonov | first4=Trifon | last5=Künstler | first5=Andreas
| journal=Astronomy and Astrophysics
| volume=574A | issue=2 | pages=116–129 | date=2015
| bibcode=2015A&A...574A.116R | doi=10.1051/0004-6361/201322360
| arxiv=1412.4634 | postscript=. | hdl=10722/215277| s2cid=59334290 }} Values are based on 99% probability it is on the horizontal branch.
| title=The Perkins catalog of revised MK types for the cooler stars
| last1=Keenan | first1=Philip C. | last2=McNeil | first2=Raymond C.
| journal=Astrophysical Journal Supplement Series
| volume=71 | pages=245 | year=1989 | postscript=.
| bibcode=1989ApJS...71..245K | doi=10.1086/191373 }}
| last1=Jennens | first1=P. A. | last2=Helfer | first2=H. L.
| title=A new photometric metal abundance and luminosity calibration for field G and K giants
| journal=Monthly Notices of the Royal Astronomical Society
| volume=172 | issue=3 | pages=667–679 | date=September 1975
| bibcode=1975MNRAS.172..667J | doi=10.1093/mnras/172.3.667 | doi-access=free }}
| title=eps CMi | accessdate=2017-09-03 | postscript=. }}
}}
{{Stars of Canis Minor|state=collapsed}}
{{DEFAULTSORT:Epsilon Canis Minoris}}