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arXiv · 1008.3388

HAT-P-20b--HAT-P-23b: Four Massive Transiting Extrasolar Planets

G. Á. Bakos·J. Hartman·G. Torres·D. W. Latham·Géza Kovács·R. W. Noyes·D. A. Fischer·J. A. Johnson·G. W. Marcy·A. W. Howard·D. Kipping·G. A. Esquerdo·A. Shporer·B. Béky·L. A. Buchhave·G. Perumpilly·M. Everett·D. D. Sasselov·R. P. Stefanik·J. Lázár·I. Papp·P. Sári
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Abstract

We report the discovery of four relatively massive (2-7MJ) transiting extrasolar planets. HAT-P-20b orbits a V=11.339 K3 dwarf star with a period P=2.875317+/-0.000004d. The host star has a mass of 0.760+/-0.03 Msun, radius of 0.690+/-0.02 Rsun, Teff=4595+/-80 K, and metallicity [Fe/H]=+0.35+/-0.08. HAT-P-20b has a mass of 7.246+/-0.187 MJ, and radius of 0.867+/-0.033 RJ yielding a mean density of 13.78+/-1.50 gcm^-3 , which is the second highest value among all known exoplanets. HAT-P-21b orbits a V=11.685 G3 dwarf on an eccentric (e=0.2280+/-0.016) orbit, with a period of P=4.1244810+/-000007d. The host star has a mass of 0.95+/-0.04Msun, radius of 1.10+/-0.08Rsun, Teff=5588+/-80K, and [Fe/H]=+0.01+/-0.08. HAT-P-21b has a mass of 4.063+/-0.161MJ, and radius of 1.024+/-0.092RJ. HAT-P-22b orbits the V=9.732 G5 dwarf HD233731, with P=3.2122200+/-0.000009d. The host star has a mass of 0.92+/-0.03Msun, radius of 1.04+/-0.04Rsun, Teff=5302+/-80K, and metallicity of +0.24+/-0.08. The planet has a mass of 2.147+/-0.061 MJ, and compact radius of 1.080+/-0.058RJ. The host star also harbors an M-dwarf companion at a wide separation. Finally, HAT-P-23b orbits a V=12.432 G0 dwarf star, with a period P=1.212884+/-0.000002d. The host star has a mass of 1.13+/-0.04sun, radius of 1.20+/-0.07Rsun, Teff=5905+/-80K, and [Fe/H]=+0.15+/-0.04. The planetary companion has a mass of 2.090+/-0.111MJ, and radius of 1.368+/-0.090RJ (abridged).

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G. Á. Bakos, J. Hartman, G. Torres, D. W. Latham, Géza Kovács, R. W. Noyes, D. A. Fischer, J. A. Johnson, G. W. Marcy, A. W. Howard, D. Kipping, G. A. Esquerdo, A. Shporer, B. Béky, L. A. Buchhave, G. Perumpilly, M. Everett, D. D. Sasselov, R. P. Stefanik, J. Lázár, I. Papp, P. Sári. 2010-08-19. HAT-P-20b--HAT-P-23b: Four Massive Transiting Extrasolar Planets. https://doi.org/10.1088/0004-637x%2F742%2F2%2F116

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