TY - JOUR A1 - Ghosh, H. A1 - DePoy, D. L. A1 - Gal-Yam, A. A1 - Gaudi, B. S. A1 - Gould, A. A1 - Han, C. A1 - Lipkin, Y. A1 - Maoz, D. A1 - Ofek, E. O. A1 - Park, B. G. A1 - Pogge, R. W. A1 - Salim, S. A1 - Abe, Fumio A1 - Bennett, David P. A1 - Bond, I. A. A1 - Eguchi, S. A1 - Furuta, Y. A1 - Hearnshaw, John B. A1 - Kamiya, K. A1 - Kilmartin, Pam M. A1 - Kurata, Y. A1 - Masuda, Kimiaki A1 - Matsubara, Yutaka A1 - Muraki, Y. A1 - Noda, S. A1 - Okajima, K. A1 - Rattenbury, N. J. A1 - Sako, T. A1 - Sekiguchi, T. A1 - Sullivan, D. J. A1 - Sumi, T. A1 - Tristram, P. J. A1 - Yanagisawa, T. A1 - Yock, P. C. M. A1 - Udalski, A. A1 - Soszynski, I. A1 - Wyrzykowski, X. A1 - Kubiak, Marcin A1 - Szymanski, M. K. A1 - Pietrzynski, G. A1 - Szewczyk, O. A1 - Zebru, T1 - Potential direct single-star mass measurement N2 - We analyze the light curve of the microlensing event OGLE-2003-BLG-175/MOA-2003-BLG-45 and show that it has two properties that, when combined with future high-resolution astrometry, could lead to a direct, accurate measurement of the lens mass. First, the light curve shows clear signs of distortion due to the Earth's accelerated motion, which yields a measurement of the projected Einstein radius (r) over tilde (E). Second, from precise astrometric measurements, we show that the blended light in the event is coincident with the microlensed source to within about 15 mas. This argues strongly that this blended light is the lens and hence opens the possibility of directly measuring the lens- source relative proper motion mu(rel) and so the mass M=(c(2)/4G)mu(rel)t(E)(r) over tilde (E), where t(E) is the measured Einstein timescale. While the light-curve-based measurement of (r) over tildeE is, by itself, severely degenerate, we show that this degeneracy can be completely resolved by measuring the direction of proper motion mu(rel) Y1 - 2004 SN - 0004-637X ER - TY - JOUR A1 - Jiang, G. F. A1 - DePoy, D. L. A1 - Gal-Yam, A. A1 - Gaudi, B. S. A1 - Gould, A. A1 - Han, C. A1 - Lipkin, Y. A1 - Maoz, D. A1 - Ofek, E. O. A1 - Park, B. G. A1 - Pogge, R. W. A1 - Udalski, A. A1 - Kubiak, Marcin A1 - Szymanski, M. K. A1 - Szewczyk, O. A1 - Zerbrun, K. A1 - Wyrzykowski, L. A1 - Soszynski, I. A1 - Pietrzynski, G. A1 - Albrow, Michael D. A1 - Beaulieu, Jean-Philippe A1 - Caldwell, John A. R. A1 - Cassan, A. A1 - Coutures, C. A1 - Dominik, M. A1 - Donatowicz, J. A1 - Fouque, P. A1 - Greenhill, John A1 - Hill, K. A1 - Horne, Keith A1 - Jorgensen, S. F. A1 - Jorgensen, Uffe Grae A1 - Kane, Stephen R. A1 - Kubas, Daniel A1 - Martin, Ralph A1 - Menzies, J. W. A1 - Pollard, R. A1 - Sahu, K. C. A1 - Wambsganss, Joachim A1 - Watson, R. A1 - Williams, A. T1 - OGLE-2003-BLG-238 : Microlensing mass estimate of an isolated star N2 - Microlensing is the only known direct method to measure the masses of stars that lack visible companions. In terms of microlensing observables, the mass is given by M (c(2)/4G)(r) over tilde (E)theta(E) and so requires the measurement of both the angular Einstein radius theta(E) and the projected Einstein radius (r) over tilde (E). Simultaneous measurement of these two parameters is extremely rare. Here we analyze OGLE-2003-BLG-238, a spectacularly bright (I-min 10.3), high-magnification (A(max) 170) microlensing event. Pronounced finite-source effects permit a measurement of theta(E) = 650 muas. Although the timescale of the event is only t(E) 38 days, one can still obtain weak constraints on the microlens parallax: 4.4 AU < <(r)over tilde>(E) < 18 AU at the 1 σ level. Together these two parameter measurements yield a range for the lens mass of 0.36 M-&ODOT; < M < 1.48 M-&ODOT;. As was the case for MACHO- LMC-5, the only other single star (apart from the Sun) whose mass has been determined from its gravitational effects, this estimate is rather crude. It does, however, demonstrate the viability of the technique. We also discuss future prospects for single-lens mass measurements Y1 - 2004 SN - 0004-637X ER - TY - JOUR A1 - Keles, Engin A1 - Mallonn, Matthias A1 - Kitzmann, Daniel A1 - Poppenhäger, Katja A1 - Hoeijmakers, H. Jens A1 - Ilyin, Ilya A1 - Alexoudi, Xanthippi A1 - Carroll, Thorsten A. A1 - Alvarado-Gomez, Julian A1 - Ketzer, Laura A1 - Bonomo, Aldo S. A1 - Borsa, Francesco A1 - Gaudi, B. Scott A1 - Henning, Thomas A1 - Malavolta, Luca A1 - Molaverdikhani, Karan A1 - Nascimbeni, Valerio A1 - Patience, Jennifer A1 - Pino, Lorenzo A1 - Scandariato, Gaetano A1 - Schlawin, Everett A1 - Shkolnik, Evgenya A1 - Sicilia, Daniela A1 - Sozzetti, Alessandro A1 - Foster, Mary G. A1 - Veillet, Christian A1 - Wang, Ji A1 - Yan, Fei A1 - Strassmeier, Klaus G. T1 - The PEPSI exoplanet transit survey (PETS) I: Investigating the presence of a silicate atmosphere on the super-earth 55 Cnc e JF - Monthly notices of the Royal Astronomical Society N2 - The study of exoplanets and especially their atmospheres can reveal key insights on their evolution by identifying specific atmospheric species. For such atmospheric investigations, high-resolution transmission spectroscopy has shown great success, especially for Jupiter-type planets. Towards the atmospheric characterization of smaller planets, the super-Earth exoplanet 55 Cnc e is one of the most promising terrestrial exoplanets studied to date. Here, we present a high-resolution spectroscopic transit observation of this planet, acquired with the PEPSI instrument at the Large Binocular Telescope. Assuming the presence of Earth-like crust species on the surface of 55 Cnc e, from which a possible silicate-vapor atmosphere could have originated, we search in its transmission spectrum for absorption of various atomic and ionized species such as Fe , Fe (+), Ca , Ca (+), Mg, and K , among others. Not finding absorption for any of the investigated species, we are able to set absorption limits with a median value of 1.9 x R-P. In conclusion, we do not find evidence of a widely extended silicate envelope on this super-Earth reaching several planetary radii. KW - planets and satellites: atmospheres KW - planets and satellites: composition Y1 - 2022 U6 - https://doi.org/10.1093/mnras/stac810 SN - 0035-8711 SN - 1365-2966 VL - 513 IS - 1 SP - 1544 EP - 1556 PB - Oxford University Press CY - Oxford ER -