HD 102776

This article is about j centauri. Not to be confused with J Centauri, i Centauri, l Centauri, or ι Centauri.
j Centauri

A light curve for HD 102776, plotted from Hipparcos data[1]
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Centaurus
Right ascension 11h 49m 41.05745s[2]
Declination −63° 47′ 18.4299″[2]
Apparent magnitude (V) 4.30[3] (+4.30 - 4.39)[4]
Characteristics
Spectral type B3V[5]
U−B color index −0.59
B−V color index −0.15
Variable type γ Cas[4]
Astrometry
Radial velocity (Rv)+29.0±4.1[3] km/s
Proper motion (μ) RA: -20.76 ± 0.56[6] mas/yr
Dec.: 4.30 ± 0.48[6] mas/yr
Parallax (π)5.4391 ± 0.4369 mas[2]
Distance600 ± 50 ly
(180 ± 10 pc)
Absolute magnitude (MV)−1.98[3]
Details
Mass5.955 M☉[7]
7.2±0.1[8] M☉
Radius5.00±0.10[9] R☉
Luminosity1,342[3] L☉
Surface gravity (log g)3.20±0.03[9] cgs
Temperature20,000±200[9] K
Rotational velocity (v sin i)200±4[9] km/s
Age31.6±0.6[8] Myr
Other designations
j Cen, NSV 5357, CPD−63°1988, FK5 2944, GC 16201, HD 102776, HIP 57669, HR 4537, SAO 251602[10]
Database references
SIMBADdata

HD 102776, also known by its Bayer designation j Centauri, is a suspected astrometric binary[11] star system in the southern constellation of Centaurus. It has a blue-white hue and is faintly visible to the naked eye with a typical apparent visual magnitude of 4.30.[3] The distance to this star is approximately 600 light years based on parallax, and it is drifting further away with a radial velocity of ~29 km/s.[3] It is a member of the Lower Centaurus Crux subgroup of the Sco OB2 association.[12] HD 102776 has a relatively large peculiar velocity of 31.1 km/s and is a candidate runaway star that was ejected from its association, most likely by a supernova explosion.[13]

The stellar classification of the visible component is B3V,[5] matching a B-type main-sequence star. It is around 32[8] million years old and is spinning rapidly with estimates of its projected rotational velocity ranging from 200[9] up to 270 km, giving it an equatorial bulge that is up to 11% larger than the polar radius.[14] This is a Be star showing emission features in its Balmer lines due to a circumstellar disk of decreated gas.[15] It is classified as a suspected Gamma Cassiopeiae type variable star with a visual magnitude varying from +4.30 down to +4.39.[4]

  1. ^ Cite error: The named reference CDS was invoked but never defined (see the help page).
  2. ^ a b c Cite error: The named reference GaiaDR2 was invoked but never defined (see the help page).
  3. ^ a b c d e f Cite error: The named reference xhip was invoked but never defined (see the help page).
  4. ^ a b c Cite error: The named reference vsx was invoked but never defined (see the help page).
  5. ^ a b Cite error: The named reference Houk1979 was invoked but never defined (see the help page).
  6. ^ a b Cite error: The named reference van Leeuwen2007 was invoked but never defined (see the help page).
  7. ^ Cite error: The named reference kervella2019 was invoked but never defined (see the help page).
  8. ^ a b c Cite error: The named reference Tetzlaff_et_al_2011 was invoked but never defined (see the help page).
  9. ^ a b c d e Cite error: The named reference Arcos2018 was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference Eggleton_Tokovinin_2008 was invoked but never defined (see the help page).
  12. ^ Cite error: The named reference Brown_Verschueren_1997 was invoked but never defined (see the help page).
  13. ^ Cite error: The named reference Hoogerwerf_et_al_2001 was invoked but never defined (see the help page).
  14. ^ Cite error: The named reference vanBelle2012 was invoked but never defined (see the help page).
  15. ^ Cite error: The named reference Arcos2017 was invoked but never defined (see the help page).