Browsing by Author "Howard, A. W."

Now showing 1 - 4 of 4
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    A high obliquity orbit for the hot-jupiter Hats-14b Transiting A 5400 K Star
    (2015) Zhou, G.; Bayliss, D.; Hartman, J. D.; Fulton, B. J.; Bakos, G. Á.; Howard, A. W.; Isaacson, H.; Marcy, G. W.; Schmidt, B. P.; Jordán Colzani, Andrés Cristóbal; Brahm, R.
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    HAT-P-27b: A HOT JUPITER TRANSITING A G STAR ON A 3 DAY ORBIT
    (2011) Beky, B.; Bakos, G. A.; Hartman, J.; Torres, G.; Latham, D. W.; Jordan, A.; Arriagada, P.; Bayliss, D.; Kiss, L. L.; Kovacs, Geza; Quinn, S. N.; Marcy, G. W.; Howard, A. W.; Fischer, D. A.; Johnson, J. A.; Esquerdo, G. A.; Noyes, R. W.; Buchhave, L. A.; Sasselov, D. D.; Stefanik, R. P.; Perumpilly, G.; Lazar, J.; Papp, I.; Sari, P.
    We report the discovery of HAT-P-27b, an exoplanet transiting the moderately bright G8 dwarf star GSC 0333-00351 (V = 12.214). The orbital period is 3.039586 +/- 0.000012 days, the reference epoch of transit is 2455186.01879 +/- 0.00054 (BJD), and the transit duration is 0.0705 +/- 0.0019 days. The host star with its effective temperature 5300 +/- 90 K is somewhat cooler than the Sun and is more metal-rich with a metallicity of +0.29 +/- 0.10. Its mass is 0.94 +/- 0.04 M-circle dot and radius is 0.90(-0.04)(+0.05) R-circle dot. For the planetary companion we determine a mass of 0.660 +/- 0.033 M-J and radius of 1.038(-0.058)(+0.077) R-J. For the 30 known transiting exoplanets between 0.3 M-J and 0.8 M-J, a negative correlation between host star metallicity and planetary radius and an additional dependence of planetary radius on equilibrium temperature are confirmed at a high level of statistical significance.
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    HD 207897 b: A dense sub-Neptune transiting a nearby and bright K-type star
    (2022) Heidari, N.; Boisse, I; Orell-Miquel, J.; Hebrard, G.; Acuna, L.; Hara, N. C.; Lillo-Box, J.; Eastman, J. D.; Arnold, L.; Astudillo-Defru, N.; Adibekyan, V; Bieryla, A.; Bonfils, X.; Bouchy, F.; Barclay, T.; Brasseur, C. E.; Borgniet, S.; Bourrier, V; Buchhave, L.; Behmard, A.; Beard, C.; Batalha, N. M.; Courcol, B.; Cortes-Zuleta, P.; Collins, K.; Carmona, A.; Crossfield, I. J. M.; Chontos, A.; Delfosse, X.; Dalal, S.; Deleuil, M.; Demangeon, O. D. S.; Diaz, R. F.; Dumusque, X.; Daylan, T.; Dragomir, D.; Mena, E. Delgado; Dressing, C.; Dai, F.; Dalba, P. A.; Ehrenreich, D.; Forveille, T.; Fulton, B.; Fetherolf, T.; Gaisne, G.; Giacalone, S.; Riazi, N.; Hoyer, S.; Hobson, M. J.; Howard, A. W.; Huber, D.; Hill, M. L.; Hirsch, L. A.; Isaacson, H.; Jenkins, J.; Kane, S. R.; Kiefer, F.; Luque, R.; Latham, D. W.; Lubin, J.; Lopez, T.; Mousis, O.; Moutou, C.; Montagnier, G.; Mignon, L.; Mayo, A.; Mocnik, T.; Murphy, J. M. A.; Palle, E.; Pepe, F.; Petigura, E. A.; Rey, J.; Ricker, G.; Robertson, P.; Roy, A.; Rubenzahl, R. A.; Rosenthal, L. J.; Santerne, A.; Santos, N. C.; Sousa, S. G.; Stassun, K. G.; Stalport, M.; Scarsdale, N.; Strom, P. A.; Seager, S.; Segransan, D.; Tenenbaum, P.; Tronsgaard, R.; Udry, S.; Vanderspek, R.; Vakili, F.; Winn, J.; Weiss, L. M.
    We present the discovery and characterization of a transiting sub-Neptune that orbits the nearby (28 pc) and bright (V = 8.37) K0V star HD 207897 (TOI-1611) with a 16.20-day period. This discovery is based on photometric measurements from the Transiting Exoplanet Survey Satellite mission and radial velocity (RV) observations from the SOPHIE, Automated Planet Finder, and HIRES high-precision spectrographs. We used EXOFASTv2 to model the parameters of the planet and its host star simultaneously, combining photometric and RV data to determine the planetary system parameters. We show that the planet has a radius of 2.50 +/- 0.08 R-E and a mass of either 14.4 +/- 1.6 M-E or 15.9 +/- 1.6 M-E with nearly equal probability. The two solutions correspond to two possibilities for the stellar activity period. The density accordingly is either 5.1 +/- 0.7 g cm(-3) or 5.5(-0.7)(+0.8) g cm(-3), making it one of the relatively rare dense sub-Neptunes. The existence of this dense planet at only 0.12 AU from its host star is unusual in the currently observed sub-Neptune (2 < R-E < 4) population. The most likely scenario is that this planet has migrated to its current position.
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    TOI-503 : The First Known Brown-dwarf Am-star Binary from the TESS Mission
    (2020) Subjak, J.; Sharma, R.; Carmichael, T. W.; Johnson, M. C.; Gonzales, E. J.; Matthews, E.; Boffin, H. M. J.; Brahm Scott, Rafael; Chaturvedi, P.; Chakraborty, A.; Ciardi, D. R.; Collins, K. A.; Esposito, M.; Fridlund, M.; Gan, T. J.; Gandolfi, D.; Garcia, R. A.; Guenther, E.; Hatzes, A.; Latham, D. W.; Mathis, S.; Mathur, S.; Persson, C. M.; Relles, H. M.; Schlieder, J. E.; Barclay, T.; Dressing, C. D.; Crossfield, I.; Howard, A. W.; Rodler, F.; Zhou, G.; Quinn, S. N.; Esquerdo, G. A.; Calkins, M. L.; Berlind, P.; Stassun, K. G.; Blazek, M.; Skarka, M.; Spokova, M.; Zak, J.; Albrecht, S.; Sobrino, R. A.; Beck, P.; Cabrera, J.; Carleo, I.; Cochran, W. D.; Csizmadia, S.; Dai, F.; Deeg, H. J.; de Leon, J. P.; Eigmuller, P.; Endl, M.; Erikson, A.; Fukui, A.; Georgieva, I.; Gonzalez-Cuesta, L.; Grziwa, S.; Hidalgo, D.; Hirano, T.; Hjorth, M.; Knudstrup, E.; Korth, J.; Lam, K. W. F.; Livingston, J. H.; Lund, M. N.; Luque, R.; Rodriguez, P. M.; Murgas, F.; Narita, N.; Nespral, D.; Niraula, P.; Nowak, G.; Palle, E.; Patzold, M.; Prieto-Arranz, J.; Rauer, H.; Redfield, S.; Ribas, I.; Smith, A. M. S.; Van Eylen, V.; Kabath, P.