Leo DP is an eclipsing cramped binary star system located in the constellation Leo [5] . It is located at a distance of about 1304 light years (400 parsec) from the Sun. At least one exoplanet is drawn around this binary system [1] .
| DP Leo AB | |||
|---|---|---|---|
| Star | |||
 Lion's DP System, modeled on Celestia | |||
| Observational data ( Epoch J2000.0 ) | |||
| Type of | Double star , cataclysmic variable | ||
| Right ascension | |||
| Declination | |||
| Distance | 1304 over the years (400 parsec ) [1] | ||
| Visible magnitude ( V ) | 17.5-19 [2] | ||
| Constellation | a lion | ||
| Astrometry | |||
| Radial velocity ( R v ) | 0 km / s | ||
| Parallax (π) | 2.5 ± 0.01 mas | ||
| Absolute magnitude (V) | 9,5-11 | ||
| Specifications | |||
| Spectral class | DA / M5V | ||
| Variability | XM [2] | ||
| physical characteristics | |||
| Weight | 0.6 / 0.09-0.1 [3] [4] M ☉ | ||
| Radius | 0,0114 [4] / 0.12 R ☉ | ||
| Age | no data of years | ||
| Temperature | 13,500 / 3000 K K | ||
| Luminosity | 0,00449 / 0,00105 L ☉ | ||
| |||
| Information in databases | |||
| SIMBAD | data | ||
Content
Star System
The system consists of a massive (mass of 0.6 solar) white dwarf ( evolved star, which no longer radiates energy through thermonuclear fusion ) and an extremely low-mass red dwarf (mass of 0.09-0.1 mass of the Sun ). The red dwarf fills its Roche lobe and its substance flows to a nearby companion. This star belongs to the type of AM Hercules (AM Her) or " polar ", cataclysmic variables in which the magnetic field of the star ( white dwarf ) completely determines the shape of the accretion flow of the system. Two stars revolve around their common center of mass in just 89.9 minutes (about 1.5 hours) [6] .
The overall luster of the system is the sum of the white dwarf's radiance, the bright hot spot on its surface, at the place where the matter of the low-mass star falls on the surface of the white dwarf, and the accretion stream.
The inclination of the stars orbit to the line of sight is 79.5 degrees [6] .
Planet
On November 17, 2010, a group of German astronomers made a statement about the discovery of the planet DP Lev b in this system. The presence of a third object in this system was predicted in 2002 [4] .
The planet is a massive gas giant , the minimum mass of which ( m sin i ) is estimated at 6 ± 0.5 Jupiter masses, which is drawn in a very elongated elliptical orbit (eccentricity ~ 0.39 [7] ) and makes a complete revolution around the binary star system for 10230 ± 730 Earth days (28 ± 2 years). Pericenter distance - 5 a. e. The distance in the apocenter is 11.4 a. e , the semi-major axis - 8.2 ± 0.4 a. e.
The authors of the study note that the Leo b Planet DP could have been formed both in the protoplanetary disk , at about the same time as the stars, and later in the gas disk at the stage of the common envelope [6] .
| Planet | Weight ( M J ) | Radius ( R j ) | Period of treatment ( years ) | Big axis orbits ( au ) | Eccentricity orbits |
|---|---|---|---|---|---|
| b | ≥6.1 ± 0.5 | ? | 28.0 ± 2 | 8.2 ± 0.4 | 0.39 ± 0.13 |
See also
- Planet with multiple orbits
Notes
- ↑ 1 2 Qian, S.-B .; Liao, W.-P .; Zhu, L.-Y .; Dai, Z.-B. Giant Extrasolar Planet of Orbiting the Polar DP Leo (Eng.) // The Astrophysical Journal : journal. - IOP Publishing , 2010. - Vol. 708 , no. 1 . - P. L66 — L68 . - DOI : 10.1088 / 2041-8205 / 708/1 / L66 . - .
- ↑ 1 2 3 Query = DP Leo . General Catalog of Variable Stars . Center de Données astronomiques de Strasbourg . The appeal date is December 16, 2009.
- ↑ DP Leo on the Planetary Systems site
- ↑ 1 2 3 Schwope, AD; Hambaryan, V .; Schwarz, R .; Kanbach, G .; Gänsicke, BT A multiwavelength timing analysis of the eclipsing polar DP Leo (Eng.) // Astronomy and Astrophysics : journal. - EDP Sciences , 2002. - Vol. 392 , no. 2 - P. 541-551 . - DOI : 10.1051 / 0004-6361: 20011651 . - . - arXiv : astro-ph / 0111457 .
- ↑ DP Leo - Cataclysmic Variable. AM Her type. SIMBAD . Center de Données astronomiques de Strasbourg . The appeal date is December 16, 2009.
- ↑ 1 2 3 Massive planet next to the cataclysmic double DP Leo
- ↑ Beuermann, K .; Buhlmann, J .; Diese, J .; Dreizler, S .; Hessman, FV; Husser, T.-O .; Miller, GF; Nickol, N .; Pons, R. The giant planet of the planet orbiting the cataclysmic binary Leonis (Eng.) // Astronomy and Astrophysics : journal. - EDP Sciences , 2011. - Vol. 526 . - P. Article Number A53 . - DOI : 10.1051 / 0004-6361 / 201015942 . - . - arXiv : 1011.3905 .