Browsing by Author "Udalski, Andrzej"

Now showing 1 - 7 of 7
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    Gaia22dkvLb: A Microlensing Planet Potentially Accessible to Radial-velocity Characterization
    (2024) Wu, Zexuan; Dong, Subo; Yi, Tuan; Liu, Zhuokai; El-Badry, Kareem; Gould, Andrew; Wyrzykowski, L.; Rybicki, K. A.; Bachelet, Etienne; Christie, Grant W.; de Almeida, L.; Monard, L. A. G.; McCormick, J.; Natusch, Tim; Zielinski, P.; Chen, Huiling; Huang, Yang; Liu, Chang; Merand, A.; Mroz, Przemek; Shangguan, Jinyi; Udalski, Andrzej; Woillez, J.; Zhang, Huawei; Hambsch, Franz-Josef; Mikolajczyk, P. J.; Gromadzki, M.; Ratajczak, M.; Kruszynska, Katarzyna; Ihanec, N.; Pylypenko, Uliana; Sitek, M.; Howil, K.; Zola, Staszek; Michniewicz, Olga; Zejmo, Michal; Lewis, Fraser; Bronikowski, Mateusz; Potter, Stephen; Andrzejewski, Jan; Merc, Jaroslav; Street, Rachel; Fukui, Akihiko; Jaimes, R. Figuera; Bozza, V.; Rota, P.; Cassan, A.; Dominik, M.; Tsapras, Y.; Hundertmark, M.; Wambsganss, J.; Bakowska, K.; Slowikowska, A.
    We report discovering an exoplanet from following up a microlensing event alerted by Gaia. The event Gaia22dkv is toward a disk source rather than the traditional bulge microlensing fields. Our primary analysis yields a Jovian planet with Mp=0.59-0.05+0.15MJ at a projected orbital separation r perpendicular to=1.4-0.3+0.8 au, and the host is a similar to 1.1 M circle dot turnoff star at similar to 1.3 kpc. At r 'approximate to 14 , the host is far brighter than any previously discovered microlensing planet host, opening up the opportunity to test the microlensing model with radial velocity (RV) observations. RV data can be used to measure the planet's orbital period and eccentricity, and they also enable searching for inner planets of the microlensing cold Jupiter, as expected from the "inner-outer correlation" inferred from Kepler and RV discoveries. Furthermore, we show that Gaia astrometric microlensing will not only allow precise measurements of its angular Einstein radius theta E but also directly measure the microlens parallax vector and unambiguously break a geometric light-curve degeneracy, leading to the definitive characterization of the lens system.
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    Millimagnitude photometry for OGLE transiting extrasolar planetary transits
    (2005) Minniti, D.; Fernández Contreras, José Miguel; Gieren, Wolfgang; Pietrzynski, Grzegorz; Ruíz, María Teresa; Udalski, Andrzej; Szeifert, Thomas; Ramírez, Sebastián; Zoccali, Manuela
    VLT images in the V-band are used to make light curves of transits of candidate OGLE planets. The data for some of the targets are complemented with NTT K-band images. Using difference image photometry, we are able to achieve milli-mag errors in the individual datapoints. Here we discuss the observations, and data reductions. We also present the preliminary results for OGLE-TR-109, arguing that it is likely to be a new transiting planet....
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    Millimagnitude photometry for transiting extrasolar planetary candidates.: II. transits of OGLE-TR-113-B in the optical and near-ir
    (2007) Diaz, Rodrigo F.; Ramirez, Sebastían; Fernandez, José Miguel; Gallardo, José; Gieren, Wolfgang; Ivanov, Valentin D.; Mauas, Pablo; Minniti, Dante; Pietrzynski, Grzegorz; Perez, Felipe; Ruiz, Maria Teresa; Udalski, Andrzej; Zoccali, Manuela
    We present precise V-and K-s-band transit photometry for the planetary host star OGLE-TR-113. Using the Ks-band photometry, we confirm the dwarf nature of OGLE-TR-113 and obtain new estimates for its effective temperature, distance, and reddening. We employ the V-band photometry to obtain planetary and orbit parameters from the transit fit, alpha = 0.0232 +/- 0: 0038 AU, orbital period P = 1.4324752 +/- 0.0000015 day, i = 86.7-90, and R-p 1.09 +/- 0.09 R-J. These values are in excellent agreement with previous works. Assuming a mass M-p 1.32 +/- 0.19 M-J for the planet, we obtain its mean density p = 1.26 +/- 0.50 g cm(-3), also in agreement with previous works. The transit observed in the K-s-band has a larger scatter, and we find its amplitude to be consistent with that in the V band. In this way, we find an independent confirmation of the planetary nature of OGLE-TR-113b.
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    OGLE-2019-BLG-0825: Constraints on the Source System and Effect on Binary-lens Parameters Arising from a Five-day Xallarap Effect in a Candidate Planetary Microlensing Event
    (2023) Satoh, Yuki; Koshimoto, Naoki; Bennett, David A.; Sumi, Takahiro; Rattenbury, Nicholas; Suzuki, Daisuke; Miyazaki, Shota; Bond, Ian; Udalski, Andrzej; Gould, Andrew; Bozza, Valerio; Dominik, Martin; Hirao, Yuki; Kondo, Iona; Kirikawa, Rintaro; Hamada, Ryusei; Abe, Fumio; Barry, Richard; Bhattacharya, Aparna; Fujii, Hirosane; Fukui, Akihiko; Fujita, Katsuki; Ikeno, Tomoya; Ishitani Silva, Stela; Itow, Yoshitaka; Matsubara, Yutaka; Matsumoto, Sho; Muraki, Yasushi; Niwa, Kosuke; Okamura, Arisa J.; Olmschenk, Greg; Ranc, Clement; Toda, Taiga; Tomoyoshi, Mio; Tristram, Paul; Vandorou, Aikaterini; Yama, Hibiki; Yamashita, Kansuke; Mroz, Przemek; Poleski, Radoslaw; Skowron, Jan; Szymanski, Michal K.; Poleski, Radek A.; Soszynski, Igor; Pietrukowicz, Pawel; Kozlowski, Szymon; Ulaczyk, Krzysztof D.; Rybicki, Krzysztof; Iwanek, Patryk; Wrona, Marcin; Gromadzki, Mariusz; Albrow, Michael; Chung, Sun-Ju; Han, Cheongho; Hwang, Kyu-Ha; Kim, Doeon; Jung, Youn Kil; Kim, Hyoun Woo C.; Ryu, Yoon-Hyun; Shin, In-Gu; Shvartzvald, Yossi; Yang, Hongjing; Yee, Jennifer; Zang, Weicheng; Cha, Sang-Mok; Kim, Dong-Jin; Kim, Seung-Lee W.; Lee, Chung-Uk G.; Lee, Dong-Joo; Lee, Yongseok; Park, Byeong-Gon; Pogge, Richard; Jorgensen, Uffe; Longa-Pena, Penelope; Sajadian, Sedighe; Skottfelt, Jesper; Snodgrass, Colin; Tregloan-Reed, Jeremy; Bach-Moller, Nanna; Burgdorf, Martin; D'Ago, Giuseppe; Haikala, Lauri; Hitchcock, James; Hundertmark, Markus; Khalouei, Elahe; Peixinho, Nuno; Rahvar, Sohrab; Southworth, John; Spyratos, Petros
    We present an analysis of microlensing event OGLE-2019-BLG-0825. This event was identified as a planetary candidate by preliminary modeling. We find that significant residuals from the best-fit static binary-lens model exist and a xallarap effect can fit the residuals very well and significantly improves chi (2) values. On the other hand, by including the xallarap effect in our models, we find that binary-lens parameters such as mass ratio, q, and separation, s, cannot be constrained well. However, we also find that the parameters for the source system such as the orbital period and semimajor axis are consistent between all the models we analyzed. We therefore constrain the properties of the source system better than the properties of the lens system. The source system comprises a G-type main-sequence star orbited by a brown dwarf with a period of P similar to 5 days. This analysis is the first to demonstrate that the xallarap effect does affect binary-lens parameters in planetary events. It would not be common for the presence or absence of the xallarap effect to affect lens parameters in events with long orbital periods of the source system or events with transits to caustics, but in other cases, such as this event, the xallarap effect can affect binary-lens parameters.
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    Spitzer Microlensing Parallax for OGLE-2017-BLG-0896 Reveals a Counter-rotating Low-mass Brown Dwarf
    (2019) Shvartzvald, Yossi; Yee, Jennifer C.; Skowron, Jan; Lee, Chung-Uk; Udalski, Andrzej; Novati, Sebastiano Calchi; Bozza, Valerio; Beichman, Charles A.; Bryden, Geoffery; Rabus, Markus
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    The Araucaria Project: The First-Overtone Classical Cepheid in the Eclipsing System OGLE-LMC-CEP-2532
    (2015) Pilecki, Bogumil; Graczyk, Dariusz; Gieren Waiblinger, Wolfgang Paul; Pietrzynski, Grzegorz; Thompson, Ian B; Smolec, Radoslaw; Udalski, Andrzej; Soszynski, Igor; Konorski, Piotr; Catelan, Márcio; Gallenne, Alexandre; Minniti, D.; Taormina, Mónica
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    THE SPITZER MICROLENSING PROGRAM AS A PROBE FOR GLOBULAR CLUSTER PLANETS: ANALYSIS OF OGLE-2015-BLG-0448
    (2016) Poleski, Radoslaw; Zhu, Wei; Christie, Grant W.; Udalski, Andrzej; Gould, Andrew; Bachelet, Etienne; Skottfelt, Jesper; Novati, Sebastiano Calchi; Szymanski, M. K.; Soszynski, I.; Pietrzynski, G.; Wyrzykowski, L.; Ulaczyk, K.; Pietrukowicz, P.; Kozlowski, Szymon; Skowron, J.; Mroz, P.; Pawlak, M.; Beichman, C.; Bryden, G.; Carey, S.; Fausnaugh, M.; Gaudi, B. S.; Henderson, C. B.; Pogge, R. W.; Shvartzvald, Y.; Wibking, B.; Yee, J. C.; Beatty, T. G.; Eastman, J. D.; Drummond, J.; Friedmann, M.; Henderson, M.; Johnson, J. A.; Kaspi, S.; Maoz, D.; McCormick, J.; McCrady, N.; Natusch, T.; Ngan, H.; Porritt, I.; Relles, H. M.; Sliski, D. H.; Tan, T. G.; Wittenmyer, R. A.; Wright, J. T.; Street, R. A.; Tsapras, Y.; Bramich, D. M.; Horne, K.; Snodgrass, C.; Steele, I. A.; Menzies, J.; Jaimes, R. Figuera; Wambsganss, J.; Schmidt, R.; Cassan, A.; Ranc, C.; Mao, S.; Bozza, V.; Dominik, M.; Hundertmark, M. P. G.; Jorgensen, U. G.; Andersen, M. I.; Burgdorf, M. J.; Ciceri, S.; D'Ago, G.; Evans, D. F.; Gu, S. H.; Hinse, T. C.; Kains, N.; Kerins, E.; Korhonen, H.; Kuffmeier, M.; Mancini, L.; Popovas, A.; Rabus, M.; Rahvar, S.; Rasmussen, R. T.; Scarpetta, G.; Southworth, J.; Surdej, J.; Unda-Sanzana, E.; Verma, P.; von Essen, C.; Wang, Y. B.; Wertz, O.
    The microlensing event OGLE-2015-BLG-0448 was observed by Spitzer and lay within the tidal radius of the globular cluster NGC 6558. The event had moderate magnification and was intensively observed, hence it had the potential to probe the distribution of planets in globular clusters. We measure the proper motion of NGC 6558 (mu(cl) (N, E) = (+0.36 +/- 0.10, +1.42 +/- 0.10) mas yr(-1)) as well as the source and show that the lens is not a cluster member. Even though this particular event does not probe the distribution of planets in globular clusters, other potential cluster lens events can be verified using our methodology. Additionally, we find that microlens parallax measured using Optical Gravitational Lens Experiment (OGLE) photometry is consistent with the value found based on the light curve displacement between the Earth and Spitzer.