HAT-P-28

HAT-P-28 is the primary of a binary star system about 1320 light-years away. It is a G-type main-sequence star. The star’s age is older than the Sun`s at 6.1+2.6
−1.9 billion years.[2] HAT-P-28 is slightly enriched in heavy elements, having a 130% concentration of iron compared to the Sun. Since 2014, the binary star system is suspected to be surrounded by a debris disk with a 6.1″(2500 AU) radius.[6]

HAT-P-28
Observation data
Epoch J2000      Equinox J2000
Constellation Andromeda
Right ascension 00h 52m 00.1878s[1]
Declination +34° 43′ 42.2030″[1]
Apparent magnitude (V) 13.03[2]
Characteristics
Evolutionary stage main-sequence star
Spectral type G
Astrometry
Radial velocity (Rv)48.06[1] km/s
Proper motion (μ) RA: 25.519[1] mas/yr
Dec.: 2.859[1] mas/yr
Parallax (π)2.4633 ± 0.0337[3] mas
Distance1,320 ± 20 ly
(406 ± 6 pc)
Orbit[4]
PrimaryHAT-P-28
CompanionHAT-P-28 B
Semi-major axis (a)0.994±0.002"
(404 AU)
Details[5]
Mass1.02±0.05 M☉
Radius1.10+0.09
−0.07 R☉
Luminosity1.13+0.23
−0.16[2] L☉
Surface gravity (log g)4.36±0.06[2] cgs
Temperature5680±90[2] K
Metallicity [Fe/H]0.12±0.08[2] dex
Rotational velocity (v sin i)0.2+0.5
−0.2[2] km/s
Age6.1+2.6
−1.9[2] Gyr
Other designations
HAT-P-28, Gaia DR2 363702817083391232, GSC 02284-00503, 2MASS J00520018+3443422[1]
Database references
SIMBADdata

The red dwarf stellar companion was detected in 2015 at a projected separation of 0.972″[7] and confirmed in 2016 to be either bound or comoving.[4]

Planetary system

In 2011 a transiting hot Jupiter planet b was detected on a nearly circular orbit. The planetary equilibrium temperature is 1384±52 K.[2] No orbital decay was detected as in 2018, despite the close proximity of the planet to the host star.[5]


The HAT-P-28 planetary system[5][2]
Companion
(in order from star)		 Mass Semimajor axis
(AU)		 Orbital period
(days)		 Eccentricity Inclination Radius
b 0.626±0.037 MJ 0.0434±0.0007 3.257215±0.000007 0.051±0.033 88.0±0.9° 1.190+0.102
−0.075 RJ

References
  1. "HAT-P-28". SIMBAD. Centre de données astronomiques de Strasbourg.
  2. Buchhave, L. A.; Bakos, G. Á.; Hartman, J. D.; Torres, G.; Latham, D. W.; Andersen, J.; Kovács, G.; Noyes, R. W.; Shporer, A.; Esquerdo, G. A.; Fischer, D. A.; Johnson, J. A.; Marcy, G. W.; Howard, A. W.; Béky, B.; Sasselov, D. D.; Fűrész, G.; Quinn, S. N.; Stefanik, R. P.; Szklenár, T.; Berlind, P.; Calkins, M. L.; Lázár, J.; Papp, I.; Sári, P. (2011), "HAT-P-28b AND HAT-P-29b: TWO SUB-JUPITER MASS TRANSITING PLANETS", The Astrophysical Journal, 733 (2): 116, arXiv:1103.1813, doi:10.1088/0004-637X/733/2/116, S2CID 119293967
  3. Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
  4. Ngo, Henry; Knutson, Heather A.; Hinkley, Sasha; Bryan, Marta; Crepp, Justin R.; Batygin, Konstantin; Crossfield, Ian; Hansen, Brad; Howard, Andrew W.; Johnson, John A.; Mawet, Dimitri; Morton, Timothy D.; Muirhead, Philip S.; Wang, Ji (2016), "FRIENDS OF HOT JUPITERS. IV. STELLAR COMPANIONS BEYOND 50 au MIGHT FACILITATE GIANT PLANET FORMATION, BUT MOST ARE UNLIKELY TO CAUSE KOZAI–LIDOV MIGRATION", The Astrophysical Journal, 827: 8, arXiv:1606.07102, doi:10.3847/0004-637X/827/1/8, S2CID 41083068
  5. Penev, Kaloyan; Bouma, L. G.; Winn, Joshua N.; Hartman, Joel D. (2018), "Empirical Tidal Dissipation in Exoplanet Hosts from Tidal Spin-up", The Astronomical Journal, 155 (4): 165, arXiv:1802.05269, doi:10.3847/1538-3881/aaaf71, PMC 6510550, PMID 31080254, S2CID 64370118
  6. Merín, Bruno; Ardila, David R.; Ribas, Álvaro; Bouy, Hervé; Bryden, Geoffrey; Stapelfeldt, Karl; Padgett, Deborah (2014), "Herschel/PACS photometry of transiting-planet host stars with candidate warm debris disks", Astronomy & Astrophysics, 569: A89, arXiv:1409.0572, doi:10.1051/0004-6361/201322956, S2CID 10038821
  7. Wöllert, Maria; Brandner, Wolfgang (2015), "A Lucky Imaging search for stellar sources near 74 transit hosts", Astronomy & Astrophysics, 579: A129, arXiv:1506.05456, doi:10.1051/0004-6361/201526525, S2CID 118903879

This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.