Browsing by Author "Gillon, M."

Now showing 1 - 9 of 9
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    HATS-47b, HATS-48Ab, HATS-49b, and HATS-72b : Four Warm Giant Planets Transiting K Dwarfs
    (2020) Hartman, J. D.; Jordán Colzani, Andrés Cristóbal; Bayliss, D.; Bakos, G. A.; Bento, J.; Bhatti, W.; Brahm Scott, Rafael; Csubry, Z.; Espinoza, N.; Henning, T.; Mancini, L.; Penev, K.; Rabus, Markus; Sarkis, P.; Suc, V.; de Val-Borro, M.; Zhou, G.; Crane, J. D.; Shectman, S.; Teske, J. K.; Wang, S. X.; Butler, R. P.; Lazar, J.; Papp, I.; Sari, P.; Anderson, D. R.; Hellier, C.; West, R. G.; Barkaoui, K.; Pozuelos, F. J.; Jehin, E.; Gillon, M.; Nielsen, L.; Lendl, M.; Udry, S.; Ricker, G. R.; Vanderspek, R.; Latham, D. W.; Seager, S.; Winn, J. N.; Christiansen, J.; Crossfield, I. J. M.; Henze, C. E.; Jenkins, J. M.; Smith, J. C.; Ting, E. B.
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    Larger and faster : revised properties and a shorter orbital period for the WASP-57 planetary system from a pro-am collaboration
    (2015) Southworth, J.; Mancini, L.; Tregloan-Reed, J.; Novati, S.; Ciceri, S.; D'Ago, G.; Delrez, L.; Dominik, M.; Evans, D.; Rabus, Markus; Jehin, E.; Jorgensen, U.; Haugbolle, T.; Lend, M.; Arena, C.; Gillon, M.
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    OGLE-TR-211 -: a new transiting inflated hot Jupiter from the OGLE survey and ESO LP666 spectroscopic follow-up program
    (2008) Udalski, A.; Pont, F.; Naef, D.; Melo, C.; Bouchy, F.; Santos, N. C.; Moutou, C.; Diaz, R. F.; Gieren, W.; Gillon, M.; Hoyer, S.; Mayor, M.; Mazeh, T.; Minniti, D.; Pietrzynski, G.; Queloz, D.; Ramirez, S.; Ruiz, M. T.; Shporer, A.; Tamuz, O.; Udry, S.; Zoccali, M.; Kubiak, M.; Szymanski, M. K.; Soszynski, I.; Szewczyk, O.; Ulaczyk, K.; Wyrzykowski, L.
    We present results of the photometric campaign for planetary and low-luminosity object transits conducted by the OGLE survey in the 2005 season (Campaign #5). About twenty of the most promising candidates discovered in these data were subsequently verified spectroscopically with the VLT/FLAMES spectrograph.
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    Physical properties of Centaur (60558) 174P/Echeclus from stellar occultations
    (2024) Pereira, C. L.; Braga-Ribas, F.; Sicardy, B.; Gomes-Junior, A. R.; Ortiz, J. L.; Branco, H. C.; Camargo, J. I. B.; Morgado, B. E.; Vieira-Martins, R.; Assafin, M.; Benedetti-Rossi, G.; Desmars, J.; Emilio, M.; Morales, R.; Rommel, F. L.; Hayamizu, T.; Gondou, T.; Jehin, E.; Artola, R. A.; Asai, A.; Colazo, C.; Ducrot, E.; Duffard, R.; Fabrega, J.; Fernandez-Valenzuela, E.; Gillon, M.; Horaguchi, T.; Ida, M.; Kitazaki, K.; Mammana, L. A.; Maury, A.; Melita, M.; Morales, N.; Moya-Sierralta, C.; Owada, M.; Pollock, J.; Sanchez, J. L.; Santos-Sanz, P.; Sasanuma, N.; Sebastian, D.; Triaud, A.; Uchiyama, S.; Vanzi, L.; Watanabe, H.; Yamamura, H.
    The Centaur (60558) Echeclus was discovered on 2000 March 03, orbiting between the orbits of Jupiter and Uranus. After exhibiting frequent outbursts, it also received a comet designation, 174P. If the ejected material can be a source of debris to form additional structures, studying the surroundings of an active body like Echeclus can provide clues about the formation scenarios of rings, jets, or dusty shells around small bodies. Stellar occultation is a handy technique for this kind of investigation, as it can, from Earth-based observations, detect small structures with low opacity around these objects. Stellar occultation by Echeclus was predicted and observed in 2019, 2020, and 2021. We obtain upper detection limits of rings with widths larger than 0.5km and optical depth of tau = 0.02. These values are smaller than those of Chariklo's main ring; in other words, a Chariklo-like ring would have been detected. The occultation observed in 2020 provided two positive chords used to derive the triaxial dimensions of Echeclus based on a 3D model and pole orientation available in the literature. We obtained a = 37.0 +/- 0.6km, b = 28.4 +/- 0.5km, and c = 24.9 +/- 0.4km, resulting in an area-equivalent radius of 30.0 +/- 0.5km. Using the projected limb at the occultation epoch and the available absolute magnitude (), we calculate an albedo of p(v) = 0.050 +/- 0.003. Constraints on the object's density and internal friction are also proposed.
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    PLUTO's ATMOSPHERE FROM STELLAR OCCULTATIONS IN 2012 AND 2013
    (2015) Dias-Oliveira, A.; Sicardy, B.; Lellouch, E.; Vieira-Martins, R.; Assafin, M.; Camargo, J. I. B.; Braga-Ribas, F.; Gomes-Junior, A. R.; Benedetti-Rossi, G.; Colas, F.; Decock, A.; Doressoundiram, A.; Dumas, C.; Emilio, M.; Fabrega Polleri, J.; Gil-Hutton, R.; Gillon, M.; Girard, J. H.; Hau, G. K. T.; Ivanov, V. D.; Jehin, E.; Lecacheux, J.; Leiva, R.; Lopez-Sisterna, C.; Mancini, L.; Manfroid, J.; Maury, A.; Meza, E.; Morales, N.; Nagy, L.; Opitom, C.; Ortiz, J. L.; Pollock, J.; Roques, F.; Snodgrass, C.; Soulier, J. F.; Thirouin, A.; Vanzi, L.; Widemann, T.; Reichart, D. E.; LaCluyze, A. P.; Haislip, J. B.; Ivarsen, K. M.; Dominik, M.; Jorgensen, U.; Skottfelt, J.
    We analyze two multi-chord stellar occultations by Pluto that were observed on 2012 July 18th and 2013 May 4th, and respectively monitored from five and six sites. They provide a total of fifteen light curves, 12 of which were used for a simultaneous fit that uses a unique temperature profile, assuming a clear (no haze) and pure N-2 atmosphere, but allowing for a possible pressure variation between the two dates. We find a solution that satisfactorily fits (i.e., within the noise level) all of the 12 light curves, providing atmospheric constraints between similar to 1190 km (pressure similar to 11 mu bar) and similar to 1450 km (pressure similar to 0.1 mu bar) from Pluto's center. Our main results are: (1) the best-fitting temperature profile shows a stratosphere with a strong positive gradient between 1190 km (at 36 K, 11 mu bar) and r = 1215 km (6.0 mu bar), where a temperature maximum of 110 K is reached; above it is a mesosphere with a negative thermal gradient of -0.2 K km(-1) up to similar to 1390 km (0.25 mu bar), where the mesosphere connects itself to a more isothermal upper branch around 81 K; (2) the pressure shows a small (6%) but significant increase (6 sigma level) between the two dates; (3) without a troposphere, Pluto's radius is found to be R-P = 1190 +/- 5 km. Allowing for a troposphere, R-P is constrained to lie between 1168 and 1195 km; and (4) the currently measured CO abundance is too small to explain the mesospheric negative thermal gradient. Cooling by HCN is possible, but only if this species is largely saturated. Alternative explanations like zonal winds or vertical compositional variations of the atmosphere are unable to explain the observed mesospheric negative thermal gradient.
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    The "666" collaboration on OGLE transits I.: I. Accurate radius of the planets OGLE-TR-10b and OGLE-TR-56b with VLT deconvolution photometry
    (2007) Pont, F.; Moutou, C.; Gillon, M.; Udalski, A.; Bouchy, F.; Fernandes, J. M.; Gieren, W.; Mayor, M.; Mazeh, T.; Minniti, D.; Melo, C.; Naef, D.; Pietrzynski, G.; Queloz, D.; Ruiz, M. T.; Santos, N. C.; Udry, S.
    Transiting planets are essential to study the structure and evolution of extra-solar planets. For that purpose, it is important to measure precisely the radius of these planets. Here we report new high-accuracy photometry of the transits of OGLE-TR-10 and OGLE-TR-56 with VLT/FORS1. One transit of each object was covered in Bessel V and R filters, and treated with the deconvolution-based photometry algorithm DECPHOT, to ensure accurate millimagnitude light curves. Together with earlier spectroscopic measurements, the data imply a radius of 1.22(-0.07)(+0.12) R-J for OGLE-TR-10b and 1.30 +/- 0.05 R-J for OGLE-TR-56b. A re-analysis of the original OGLE photometry resolves an earlier discrepancy about the radius of OGLE-TR-10. The transit of OGLE-TR-56 is almost grazing, so that small systematics in the photometry can cause large changes in the derived radius. Our study confirms both planets as inflated hot Jupiters, with large radii comparable to that of HD 209458b and at least two other recently discovered transiting gas giants.
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    The EBLM project - VIII. First results for M-dwarf mass, radius, and effective temperature measurements using CHEOPS light curves
    (2021) Swayne, M., I; Maxted, P. F. L.; Triaud, A. H. M. J.; Sousa, S. G.; Broeg, C.; Floren, H-G; Guterman, P.; Simon, A. E.; Boisse, I; Bonfanti, A.; Martin, D.; Santerne, A.; Salmon, S.; Standing, M. R.; Van Grootel, V.; Wilson, T. G.; Alibert, Y.; Alonso, R.; Anglada Escude, G.; Asquier, J.; Barczy, T.; Barrado, D.; Barros, S. C. C.; Battley, M.; Baumjohann, W.; Beck, M.; Beck, T.; Bekkelien, A.; Benz, W.; Billot, N.; Bonfils, X.; Brandeker, A.; Busch, M-D; Cabrera, J.; Charnoz, S.; Cameron, A. Collier; Csizmadia, Sz; Davies, M. B.; Deleuil, M.; Deline, A.; Delrez, L.; Demangeon, O. D. S.; Demory, B-O; Dransfield, G.; Ehrenreich, D.; Erikson, A.; Fortier, A.; Fossati, L.; Fridlund, M.; Futyan, D.; Gandolfi, D.; Gillon, M.; Guedel, M.; Hebrard, G.; Heidari, N.; Hellier, C.; Heng, K.; Hobson, M.; Hoyer, S.; Isaak, K. G.; Kiss, L.; Hodzic, V. Kunovac; Lalitha, S.; Laskar, J.; des Etangs, A. Lecavelier; Lendl, M.; Lovis, C.; Magrin, D.; Marafatto, L.; McCormac, J.; Miller, N.; Nascimbeni, V; Olofsson, G.; Ottensamer, R.; Pagano, I; Palle, E.; Peter, G.; Piotto, G.; Pollacco, D.; Queloz, D.; Ragazzoni, R.; Rando, N.; Rauer, H.; Ribas, I; Santos, N. C.; Scandariato, G.; Segransan, D.; Smith, A. M. S.; Steinberger, M.; Steller, M.; Szabo, Gy M.; Thomas, N.; Udry, S.; Walter, I; Walton, N. A.; Willett, E.
    The accuracy of theoretical mass, radius, and effective temperature values for M-dwarf stars is an active topic of debate. Differences between observed and theoretical values have raised the possibility that current theoretical stellar structure and evolution models are inaccurate towards the low-mass end of the main sequence. To explore this issue, we use the CHEOPS satellite to obtain high-precision light curves of eclipsing binaries with low-mass stellar companions. We use these light curves combined with the spectroscopic orbit for the solar-type companion to measure the mass, radius, and effective temperature of the M-dwarf star. Here, we present the analysis of three eclipsing binaries. We use the pycheops data analysis software to fit the observed transit and eclipse events of each system. Two of our systems were also observed by the TESS satellite - we similarly analyse these light curves for comparison. We find consistent results between CHEOPS and TESS, presenting three stellar radii and two stellar effective temperature values of low-mass stellar objects. These initial results from our on-going observing programme with CHEOPS show that we can expect to have similar to 24 new mass, radius, and effective temperature measurements for very low-mass stars within the next few years.
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    TOI-150b and TOI-163b : two transiting hot Jupiters, one eccentric and one inflated, revealed by TESS near and at the edge of the JWST CVZ
    (2019) Kossakowski, D.; Espinoza, N.; Brahm Scott, Rafael; Jordán Colzani, Andrés Cristóbal; Henning, T.; Rojas, F.; Kurster, M.; Sarkis, P.; Schlecker, M.; Pozuelos, F. J.; Barkaoui, K.; Jehin, E.; Gillon, M.; Matthews, E.; Horch, E. P.; Ciardi, D. R.; Rossfield, I. J. M.; Gonzales, E.; Howell, S. B.; Matson, R.; Schlieder, J.; Jenkins, J.; Ricker, G.; Seager, S.; Winn, J. N.; Li, J.; Rose, M. E.; Smith, J. C.; Dynes, S.; Morgan, E.; Villaseñor, J. N.; Charbonneau, D.; Jaffe, T.; Yu, L.; Bakos, G.; Bhatti, W.; Bouchy, F.; Collins, K. A.; Collins, K. I.; Csubry, Z.; Evans, P.; Jensen, E. L. N.; Lovis, C.; Marmier, M.; Nielsen, L. D.; Osip, D.; Pepe, F.; Relles, H. M.; Segransan, D.; Shporer, A.; Stockdale, C.; Suc, V.; Turner, O.; Udry, S.
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    Two Transiting Hot Jupiters from the WASP Survey : WASP-150b and WASP-176b
    (2020) Cooke, B. F.; Pollacco, D.; Almleaky, Y.; Barkaoui, K.; Benkhaldoun, Z.; Blake, J. A.; Bouchy, F.; Boumis, P.; Brown, D. J. A.; D’Ago, Giuseppe; Bruni, I.; Burdanov, A.; Cameron, A. C.; Chote, P.; Daassou, A.; Dalal, S.; Damasso, M.; Delrez, L.; Doyle, A. P.; Ducrot, E.; Gillon, M.; Hebrard, G.; Hellier, C.; Henning, T.; Jehin, E.; Kiefer, F.; King, G. W.; Liakos, A.; Lopez, T.; Mancini, L.; Mardling, R.; Maxted, P. F. L.; McCormac, J.; Murray, C.; Nielsen, L. D.; Osborn, H.; Palle, E.; Pepe, F.; Pozuelos, F. J.; Prieto-Arranz, J.; Queloz, D.; Schanche, N.; Segransan, D.; Smalley, B.; Southworth, J.; Thompson, S.; Turner, O.; Udry, S.; Velasco, S.; West, R.; Wheatley, P