Examinando por Autor "Daylan, Tansu"

Mostrando 1 - 2 de 2
  • No hay miniatura disponible
    Ítem
    A super-Earth and two sub-Neptunes transiting the nearby and quiet M dwarf TOI-270
    (Nature Research, 2019-12-01) Günther, Maximilian N.; Pozuelos, Francisco J.; Dittmann, Jason A.; Dragomir, Diana; Kane, Stephen R.; Daylan, Tansu; Feinstein, Adina D.; Huang, Chelsea X.; Morton, Timothy D.; Bonfanti, Andrea; Bouma, L. G.; Burt, Jennifer; Collins, Karen A.; Lissauer, Jack J.; Matthews, Elisabeth; Montet, Benjamin T.; Vanderburg, Andrew; Wang, Songhu; Winters, Jennifer G.; Ricker, George R.; Vanderspek, Roland K.; Latham, David W.; Seager, Sara; Winn, Joshua N.; Jenkins, Jon M.; Armstrong, James D.; Barkaoui, Khalid; Batalha, Natalie; Bean, Jacob L.; Caldwell, Douglas A.; Ciardi, David R.; Collins, Kevin I.; Crossfield, Ian; Fausnaugh, Michael; Furesz, Gabor; Gan, Tianjun; Gillon, Michaël; Guerrero, Natalia; Horne, Keith; Howell, Steve B.; Ireland, Michael; Isopi, Giovanni; Jehin, Emmanuël; Kielkopf, John F.; Lepine, Sebastien; Mallia, Franco; Matson, Rachel A.; Myers, Gordon; Palle, Enric; Quinn, Samuel N.; Relles, Howard M.; Rojas-Ayala, Bárbara; Schlieder, Joshua; Sefako, Ramotholo; Shporer, Avi; Suárez, Juan C.; Tan, Thiam-Guan; Ting, Eric B.; Twicken, Joseph D.; Waite, Ian A.
    One of the primary goals of exoplanetary science is to detect small, temperate planets passing (transiting) in front of bright and quiet host stars. This enables the characterization of planetary sizes, orbits, bulk compositions, atmospheres and formation histories. These studies are facilitated by small and cool M dwarf host stars. Here we report the Transiting Exoplanet Survey Satellite (TESS)1 discovery of three small planets transiting one of the nearest and brightest M dwarf hosts observed to date, TOI-270 (TIC 259377017, with K-magnitude 8.3, and 22.5 parsecs away from Earth). The M3V-type star is transited by the super-Earth-sized planet TOI-270 b (1.247−0.083+0.089R⊕) and the sub-Neptune-sized planets TOI-270 c (2.42 ± 0.13 R⊕) and TOI-270 d (2.13 ± 0.12 R⊕). The planets orbit close to a mean-motion resonant chain, with periods (3.36 days, 5.66 days and 11.38 days, respectively) near ratios of small integers (5:3 and 2:1). TOI-270 is a prime target for future studies because (1) its near-resonance allows the detection of transit timing variations, enabling precise mass measurements and dynamical studies; (2) its brightness enables independent radial-velocity mass measurements; (3) the outer planets are ideal for atmospheric characterization via transmission spectroscopy; and (4) the quietness of the star enables future searches for habitable zone planets. Altogether, very few systems with small, temperate exoplanets are as suitable for such complementary and detailed characterization as TOI-270.
  • No hay miniatura disponible
    Ítem
    HD 213885b: A transiting 1-d-period super-Earth with an Earth-like composition around a bright (V = 7.9) star unveiled by TESS
    (Oxford University Press, 2020-01-01) Espinoza, Néstor; Brahm, Rafael; Henning, Thomas; Jordán, Andrés; Dorn, Caroline; Rojas, Felipe; Sarkis, Paula; Kossakowski, Diana; Schlecker, Martin; Díaz, Matías R.; Jenkins, James S.; Aguilera-Gomez, Claudia; Jenkins, Jon M.; Twicken, Joseph D.; Collins, Karen A.; Lissauer, Jack; Armstrong, David J.; Adibekyan, Vardan; Barrado, David; Barros, Susana C.C.; Battley, Matthew; Bayliss, Daniel; Bouchy, François; Bryant, Edward M.; Cooke, Benjamin F.; Olivier D.S.; Dumusque, Xavier; Figueira, Pedro; Giles, Helen; Lillo-Box, Jorge; Lovis, Christophe; Nielsen, Louise D.; Pepe, Francesco; Pollacco, Don; Santos, Nuno C.; Sousa, Sergio G.; Udry, Stéphane; Wheatley, Peter J.; Turner, Oliver; Marmier, Maxime; Ségransan, Damien; Ricker, George; Latham, David; Seager, Sara; Winn, Joshua N.; Kielkopf, John F.; Hart, Rhodes; Wingham, Geof; Jensen, Eric L.N.; Hełminiak, Krzysztof G.; Tokovinin A.; Briceño C.; Ziegler, Carl; Law, Nicholas M.; Mann, Andrew W.; Daylan, Tansu; Doty, John P.; Guerrero, Natalia; Boyd, Patricia; Crossfield, Ian
    We report the discovery of the 1.008-d, ultrashort period (USP) super-Earth HD 213885b (TOI-141b) orbiting the bright (V= 7.9) star HD 213885 (TOI-141, TIC 403224672), detected using photometry from the recently launched TESS mission. Using FEROS, HARPS, and CORALIE radial velocities, we measure a precise mass of 8.8 ±0.6M⊙ for this 1.74±0.05R⊙ exoplanet, which provides enough information to constrain its bulk composition - similar to Earth's but enriched in iron. The radius, mass, and stellar irradiation of HD 213885b are, given our data, very similar to 55 Cancri e, making this exoplanet a good target to perform comparative exoplanetology of short period, highly irradiated super-Earths. Our precise radial velocities reveal an additional 4.78-d signal which we interpret as arising from a second, non-transiting planet in the system, HD 213885c, whose minimum mass of 19.9 ± 1.4 M⊙ makes it consistent with being a Neptune-mass exoplanet. The HD 213885 system is very interesting from the perspective of future atmospheric characterization, being the second brightest star to host an USP transiting super-Earth (with the brightest star being, in fact, 55 Cancri). Prospects for characterization with present and future observatories are discussed.