HD 136138
| Observation data Epoch J2000.0 Equinox J2000.0 | ||
|---|---|---|
| Constellation | Serpens | |
| Right ascension | 15h 18m 24.507s[1] | |
| Declination | +20° 34′ 21.95″[1] | |
| Apparent magnitude (V) | 5.68[2] + 15.3[3] | |
| Characteristics | ||
| Evolutionary stage | Horizontal branch + white dwarf | |
| Spectral type | G8IIIa[4] + DA1.7[3] | |
| B−V color index | 0.972±0.004[2] | |
| Variable type | Constant[5][6] | |
| Absolute magnitude (MV) | 0.65±0.15[7] | |
Semi-amplitude (K1)(primary) | 6.340±0.044 km/s | |
| Details Gyr | ||
| B | ||
| Mass | 0.59±0.12 or 0.79±0.09 M☉ | |
| Surface gravity (log g) | 8.25±0.15 cgs | |
| Temperature | 30,400±780 K | |
| Database references | ||
| SIMBAD | data | |
HD 136138, or HR 5692, is a
mas·yr−1.[8]
The radial velocity variation of this star was reported by J. R. de Medeiros and M. Mayor in 1999,
The
spectra showing marginal overabundances of s-process elements.[8] A low level of X-ray emission has been detected, which appears to be coming from the star's corona.[6]
The high level of ultraviolet flux coming from this system strongly suggests the companion is a compact white dwarf. Mass estimates put it in the range of 0.6 to 0.8 times the mass of the Sun, and the temperature is around 30,400 K.[7] It is possible that the earlier evolution of this component contaminated its partner with s-process elements, although the resulting interaction should have circularized the orbit to some degree.[5] The dwarf has a visual magnitude of 15.3 and a hydrogen-dominated atmospheric class of DA1.7.[3]
References
- ^ .
- ^ S2CID 119257644.
- ^ .
- ^ doi:10.1086/191373.
- ^ Bibcode:2009Obs...129....6G.
- ^ Bibcode:1996A&A...306..467J.
- ^ S2CID 56137377. 144.
- ^ S2CID 119224869. A151.
- ^ "HD 136138". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2020-12-22.
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