Browsing by Author "Briceño, C."

Now showing 1 - 3 of 3
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    A hot terrestrial planet orbiting the bright M dwarf L 168-9 unveiled by TESS
    (2020) Astudillo Defru, N.; Cloutier, R.; Wang, S. X.; Teske, J.; Brahm Scott, Rafael; Hellier, C.; Ricker, G.; Vanderspek, R.; Latham, D.; Seager, S.; Winn, J. N.; Jenkins, J. M.; Collins, K. A.; Stassun, K. G.; Ziegler, C.; Almenara, J. M.; Anderson, D. R.; Artigau, E.; Bonfils, X.; Bouchy, F.; Briceño, C.; Butler, R. P.; Charbonneau, D.; Conti, D. M.; Crane, J.; Crossfield, I. J. M.; Davies, M.; Delfosse, X.; Díaz, R. F.; Doyon, R.; Dragomir, D.; Eastman, J. D.; Espinoza, N.; Essack, Z.; Feng, F.; Figueira, P.; Forveille, T.; Gan, T.; Glidden, A.; Guerrero, N.; Hart, R.; Henning, T.; Horch, E. P.; Isopi, G.; Jenkins, J. S.; Jordán, A.; Kielkopf, J. F.; Law, N.; Lovis, C.; Mallia, F.
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    Large-amplitude periodic outbursts and long-period variables in the VVV VIRAC2-β data base
    (2022) Guo, Zhen; Lucas, P. W.; Smith, L. C.; Clarke, C.; Contreras Peña, C.; Bayo, A.; Briceño, C.; Elias, J.; Kurtev, R. G.; Borissova, J.; Alonso-García, J.; Minniti, D.; Catelan, Márcio; Nikzat, F.; Morris, C.; Miller, N.
    The VISTA Variables in the Via Lactea (VVV) survey obtained near-infrared photometry towards the Galactic bulge and the southern disc plane for a decade (2010-2019). We designed a modified Lomb-Scargle method to search for large-amplitude ($\Delta K_{s, 2-98{{\ \rm per\ cent}}}$ > 1.5 mag) mid to long-term periodic variables (P> 10 d) in the 2nd version of VVV Infrared Astrometric Catalogue (VIRAC2-β). In total, 1520 periodic sources were discovered, including 59 candidate periodic outbursting young stellar objects (YSOs), based on the unique morphology of the phase-folded light curves, proximity to Galactic H II regions and mid-infrared colours. Five sources are spectroscopically confirmed as accreting YSOs. Both fast-rise/slow-decay and slow-rise/fast-decay periodic outbursts were found, but fast-rise/slow-decay outbursts predominate at the highest amplitudes. The multiwavelength colour variations are consistent with a variable mass accretion process, as opposed to variable extinction. The cycles are likely to be caused by dynamical perturbations from stellar or planetary companions within the circumstellar disc. An additional search for periodic variability amongst YSO candidates in published Spitzer-based catalogues yielded a further 71 candidate periodic accretors, mostly with lower amplitudes. These resemble cases of pulsed accretion but with unusually long periods and greater regularity. The majority of other long-period variables are pulsating dusty Miras with smooth and symmetric light curves. We find that some Miras have redder W3 - W4 colours than previously thought, most likely due to their surface chemical compositions....
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    TOI-222: a single-transit TESS candidate revealed to be a 34-d eclipsing binary with CORALIE, EulerCam, and NGTS
    (2019) Lendl, M.; Bouchy, F.; Gill, S.; Nielsen, L. D.; Turner, O.; Stassun, K.; Acton, J. S.; Anderson, D. R.; Armstrong, D. J.; Bayliss, D.; Belardi, C.; Bryant, E. M.; Burleigh, M. R.; Chaushev, A.; Casewell, S. L.; Cooke, B. F.; Eigmüller, P.; Gillen, E.; Goad, M. R.; Gunther, M. N.; Hagelberg, J.; Jenkins, J. S.; Louden, T.; Marmier, M.; McCormac, J.; Moyano, M.; Pollacco, D.; Raynard, L.; Tilbrook, R. H.; Udry, S.; Vines, J. I.; West, R. G.; Wheatley, P. J.; Ricker, G.; Vanderspek, R.; Latham, D. W.; Seager, S.; Winn, J.; Jenkins, J. M.; Addison, B.; Briceño, C.; Brahm, R.; Caldwell, D. A.; Doty, J.; Espinoza, N.; Goeke, B.; Henning, T.; Jordán, A.; Krishnamurthy, A.; Law, N.; Morris, R.; Okumura, J.; Mann, A. W.; Rodriguez, J. E.; Sarkis, P.; Schlieder, J.; Twicken, J. D.; Villanueva, S.; Wittenmyer, R. A.; Wright, D. J.; Ziegle, C.
    We report the period, eccentricity, and mass determination for the Transiting Exoplanet Survey Satellite (TESS) single-transit event candidate TOI-222, which displayed a single 3000 ppm transit in the TESS 2-min cadence data from Sector 2. We determine the orbital period via radial velocity measurements (P = 33.9 d), which allowed for ground-based photometric detection of two subsequent transits. Our data show that the companion to TOI-222 is a low-mass star, with a radius of $0.18_{-0.10}^{+0.39}$ R⊙ and a mass of 0.23 ± 0.01 M⊙. This discovery showcases the ability to efficiently discover long-period systems from TESS single-transit events using a combination of radial velocity monitoring coupled with high-precision ground-based photometry.