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1. Identification of the Top TESS Objects of Interest for Atmospheric Characterization of Transiting Exoplanets with JWST

Author

Benjamin J. Hord, Eliza M.-R. Kempton, Thomas M. Evans-Soma, David W. Latham, David R. Ciardi, Diana Dragomir, Knicole D. Colón, Gabrielle Ross, Andrew Vanderburg, Zoe L. de Beurs, Karen A. Collins, Cristilyn N. Watkins, Jacob Bean, Nicolas B. Cowan, Tansu Daylan, Caroline V. Morley, Jegug Ih, David Baker, Khalid Barkaoui, Natalie M. Batalha, Aida Behmard, Alexander Belinski, Zouhair Benkhaldoun, Paul Benni, Krzysztof Bernacki, Allyson Bieryla, Avraham Binnenfeld, Pau Bosch-Cabot, François Bouchy, Valerio Bozza, Rafael Brahm, Lars A. Buchhave, Michael Calkins, Ashley Chontos, Catherine A. Clark, Ryan Cloutier, Marion Cointepas, Kevin I. Collins, Dennis M. Conti, Ian J. M. Crossfield, Fei Dai, Jerome P. de Leon, Georgina Dransfield, Courtney Dressing, Adam Dustor, Gilbert Esquerdo, Phil Evans, Sergio B. Fajardo-Acosta, Jerzy Fiołka, Raquel Forés-Toribio, Antonio Frasca, Akihiko Fukui, Benjamin Fulton, Elise Furlan, Tianjun Gan, Davide Gandolfi, Mourad Ghachoui, Steven Giacalone, Emily A. Gilbert, Michaël Gillon, Eric Girardin, Erica Gonzales, Ferran Grau Horta, Joao Gregorio, Michael Greklek-McKeon, Pere Guerra, J. D. Hartman, Coel Hellier, Ian Helm, Krzysztof G. Hełminiak, Thomas Henning, Michelle L. Hill, Keith Horne, Andrew W. Howard, Steve B. Howell, Daniel Huber, Giovanni Isopi, Emmanuel Jehin, Jon M. Jenkins, Eric L. N. Jensen, Marshall C. Johnson, Andrés Jordán, Stephen R. Kane, John F. Kielkopf, Vadim Krushinsky, Sławomir Lasota, Elena Lee, Pablo Lewin, John H. Livingston, Jack Lubin, Michael B. Lund, Franco Mallia, Christopher R. Mann, Giuseppi Marino, Nataliia Maslennikova, Bob Massey, Rachel Matson, Elisabeth Matthews, Andrew W. Mayo, Tsevi Mazeh, Kim K. McLeod, Edward J. Michaels, Teo Močnik, Mayuko Mori, Georgia Mraz, Jose A. Muñoz, Norio Narita, Krupa Natarajan, Louise Dyregaard Nielsen, Hugh Osborn, Enric Palle, Aviad Panahi, Riccardo Papini, Peter Plavchan, Alex S. Polanski, Adam Popowicz, Francisco J. Pozuelos, Samuel N. Quinn, Don J. Radford, Phillip A. Reed, Howard M. Relles, Malena Rice, Paul Robertson, Joseph E. Rodriguez, Lee J. Rosenthal, Ryan A. Rubenzahl, Nicole Schanche, Joshua Schlieder, Richard P. Schwarz, Ramotholo Sefako, Avi Shporer, Alessandro Sozzetti, Gregor Srdoc, Chris Stockdale, Alexander Tarasenkov, Thiam-Guan Tan, Mathilde Timmermans, Eric B. Ting, Judah Van Zandt, JP Vignes, Ian Waite, Noriharu Watanabe, Lauren M. Weiss, Justin Wittrock, George Zhou, Carl Ziegler, and Shay Zucker

Subjects
Exoplanet astronomy, Exoplanet atmospheres, Transit photometry, James Webb Space Telescope, Exoplanets, Astronomy, QB1-991
Abstract

JWST has ushered in an era of unprecedented ability to characterize exoplanetary atmospheres. While there are over 5000 confirmed planets, more than 4000 Transiting Exoplanet Survey Satellite (TESS) planet candidates are still unconfirmed and many of the best planets for atmospheric characterization may remain to be identified. We present a sample of TESS planets and planet candidates that we identify as “best-in-class” for transmission and emission spectroscopy with JWST. These targets are sorted into bins across equilibrium temperature T _eq and planetary radius R _p and are ranked by a transmission and an emission spectroscopy metric (TSM and ESM, respectively) within each bin. We perform cuts for expected signal size and stellar brightness to remove suboptimal targets for JWST. Of the 194 targets in the resulting sample, 103 are unconfirmed TESS planet candidates, also known as TESS Objects of Interest (TOIs). We perform vetting and statistical validation analyses on these 103 targets to determine which are likely planets and which are likely false positives, incorporating ground-based follow-up from the TESS Follow-up Observation Program to aid the vetting and validation process. We statistically validate 18 TOIs, marginally validate 31 TOIs to varying levels of confidence, deem 29 TOIs likely false positives, and leave the dispositions for four TOIs as inconclusive. Twenty-one of the 103 TOIs were confirmed independently over the course of our analysis. We intend for this work to serve as a community resource and motivate formal confirmation and mass measurements of each validated planet. We encourage more detailed analysis of individual targets by the community.

Published
2024
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2. Optical Monitoring of the Didymos–Dimorphos Asteroid System with the Danish Telescope around the DART Mission Impact

Author

Agata Rożek, Colin Snodgrass, Uffe G. Jørgensen, Petr Pravec, Mariangela Bonavita, Markus Rabus, Elahe Khalouei, Penélope Longa-Peña, Martin J. Burgdorf, Abbie Donaldson, Daniel Gardener, Dennis Crake, Sedighe Sajadian, Valerio Bozza, Jesper Skottfelt, Martin Dominik, J. Fynbo, Tobias C. Hinse, Markus Hundertmark, Sohrab Rahvar, John Southworth, Jeremy Tregloan-Reed, Mike Kretlow, Paolo Rota, Nuno Peixinho, Michael Andersen, Flavia Amadio, Daniela Barrios-López, and Nora Soledad Castillo Baeza

Subjects
Light curves, Asteroid satellites, Apollo group, Planetary probes, Astronomy, QB1-991
Abstract

The NASA’s Double-Asteroid Redirection Test (DART) was a unique planetary defence and technology test mission, the first of its kind. The main spacecraft of the DART mission impacted the target asteroid Dimorphos, a small moon orbiting the asteroid Didymos (65803), on 2022 September 26. The impact brought up a mass of ejecta which, together with the direct momentum transfer from the collision, caused an orbital period change of 33 ± 1 minutes, as measured by ground-based observations. We report here the outcome of the optical monitoring campaign of the Didymos system from the Danish 1.54 m telescope at La Silla around the time of impact. The observations contributed to the determination of the changes in the orbital parameters of the Didymos–Dimorphos system, as reported by Thomas et al., but in this paper we focus on the ejecta produced by the DART impact. We present photometric measurements from which we remove the contribution from the Didymos–Dimorphos system using an H – G photometric model. Using two photometric apertures we determine the fading rate of the ejecta to be 0.115 ± 0.003 mag day ^−1 (in a 2″ aperture) and 0.086 ± 0.003 mag day ^−1 (5″) over the first week postimpact. After about 8 days postimpact we note the fading slows down to 0.057 ± 0.003 mag day ^−1 (2″ aperture) and 0.068 ± 0.002 mag day ^−1 (5″). We include deep-stacked images of the system to illustrate the ejecta evolution during the first 18 days, noting the emergence of dust tails formed from ejecta pushed in the antisolar direction, and measuring the extent of the particles ejected Sunward to be at least 4000 km.

Published
2023
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3. 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

Author

Yuki K. Satoh, Naoki Koshimoto, David P. Bennett, Takahiro Sumi, Nicholas J. Rattenbury, Daisuke Suzuki, Shota Miyazaki, Ian A. Bond, Andrzej Udalski, Andrew Gould, Valerio Bozza, Martin Dominik, Yuki Hirao, Iona Kondo, Rintaro Kirikawa, Ryusei Hamada, Leading Authors, Fumio Abe, Richard Barry, Aparna Bhattacharya, Hirosane Fujii, Akihiko Fukui, Katsuki Fujita, Tomoya Ikeno, Stela Ishitani Silva, Yoshitaka Itow, Yutaka Matsubara, Sho Matsumoto, Yasushi Muraki, Kosuke Niwa, Arisa Okamura, Greg Olmschenk, Clément Ranc, Taiga Toda, Mio Tomoyoshi, Paul J. Tristram, Aikaterini Vandorou, Hibiki Yama, Kansuke Yamashita, The MOA Collaboration, Przemek Mróz, Radosław Poleski, Jan Skowron, Michał K. Szymański, Radek Poleski, Igor Soszyński, Paweł Pietrukowicz, Szymon Kozłowski, Krzysztof Ulaczyk, Krzysztof A. Rybicki, Patryk Iwanek, Marcin Wrona, Mariusz Gromadzki, The OGLE Collaboration, Michael D. Albrow, Sun-Ju Chung, Cheongho Han, Kyu-Ha Hwang, Doeon Kim, Youn Kil Jung, Hyoun Woo Kim, Yoon-Hyun Ryu, In-Gu Shin, Yossi Shvartzvald, Hongjing Yang, Jennifer C. Yee, Weicheng Zang, Sang-Mok Cha, Dong-Jin Kim, Seung-Lee Kim, Chung-Uk Lee, Dong-Joo Lee, Yongseok Lee, Byeong-Gon Park, Richard W. Pogge, The KMTNet Collaboration, Uffe G. Jørgensen, Penélope Longa-Peña, Sedighe Sajadian, Jesper Skottfelt, Colin Snodgrass, Jeremy Tregloan-Reed, Nanna Bach-Møller, Martin Burgdorf, Giuseppe D’Ago, Lauri Haikala, James Hitchcock, Markus Hundertmark, Elahe Khalouei, Nuno Peixinho, Sohrab Rahvar, John Southworth, Petros Spyratos, and The MiNDSTEp Collaboration

Subjects
Gravitational microlensing, Brown dwarfs, Xallarap effect, Astronomy, QB1-991
Abstract

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 χ ^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 ∼ 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.

Published
2023
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4. Terrestrial- and Neptune-mass Free-Floating Planet Candidates from the MOA-II 9 yr Galactic Bulge Survey

Author

Naoki Koshimoto, Takahiro Sumi, David P. Bennett, Valerio Bozza, Przemek Mróz, Andrzej Udalski, Nicholas J. Rattenbury, Fumio Abe, Richard Barry, Aparna Bhattacharya, Ian A. Bond, Hirosane Fujii, Akihiko Fukui, Ryusei Hamada, Yuki Hirao, Stela Ishitani Silva, Yoshitaka Itow, Rintaro Kirikawa, Iona Kondo, Yutaka Matsubara, Shota Miyazaki, Yasushi Muraki, Greg Olmschenk, Clément Ranc, Yuki Satoh, Daisuke Suzuki, Mio Tomoyoshi, Paul J. Tristram, Aikaterini Vandorou, Hibiki Yama, Kansuke Yamashita, and MOA Collaboration

Subjects
Gravitational microlensing exoplanet detection, Free floating planets, Exoplanets, Astronomy, QB1-991
Abstract

We report the discoveries of low-mass free-floating planet (FFP) candidates from the analysis of 2006–2014 MOA-II Galactic bulge survey data. In this data set, we found 6111 microlensing candidates and identified a statistical sample consisting of 3535 high-quality single-lens events with Einstein radius crossing times in the range 0.057 < t _E /days < 757, including 13 events that show clear finite-source effects with angular Einstein radii of 0.90 < θ _E / μ as < 332.54. Two of the 12 events with t _E < 1 day have significant finite-source effects, and one event, MOA-9y-5919, with t _E = 0.057 ± 0.016 days and θ _E = 0.90 ± 0.14 μ as, is the second terrestrial-mass FFP candidate to date. A Bayesian analysis indicates a lens mass of ${0.75}_{-0.46}^{+1.23}$ M _⊕ for this event. The low detection efficiency for short-duration events implies a large population of low-mass FFPs. The microlensing detection efficiency for low-mass planet events depends on both the Einstein radius crossing times and the angular Einstein radii, so we have used image-level simulations to determine the detection efficiency dependence on both t _E and θ _E . This allows us to use a Galactic model to simulate the t _E and θ _E distribution of events produced by the known stellar populations and models of the FFP distribution that are fit to the data. Methods like this will be needed for the more precise FFP demographics determinations from Nancy Grace Roman Space Telescope data.

Published
2023
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5. Cosmological Perturbations in Bouncing Cosmologies and the Case of the Pre-Big Bang Scenario

Author

Valerio Bozza

Subjects
early universe, cosmological perturbations, string cosmology, Elementary particle physics, QC793-793.5
Abstract

Pre-Big Bang cosmology inspired generations of cosmologists in attempts to cure the initial Big Bang singularity using a fundamental length scale as proposed by string theory. The existence of a phase of collapse/inflation with increasing curvature followed by a cosmic bounce has been proposed as an alternative to standard inflation in the solution of the horizon and curvature problems. However, the generation of a nearly scale-invariant spectrum of perturbations is not an automatic prediction of such scenarios. In this paper, I review some general statements about the evolution of perturbations in bouncing cosmologies and some historically significant attempts to reconcile the predicted spectra with the observations. Bouncing cosmologies and, in particular, the pre-Big Bang scenario stand as viable, although more complicated, alternatives to inflation that may still help solve current theoretical and observational tensions.

Published
2022
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6. Einstein, Planck and Vera Rubin: Relevant Encounters Between the Cosmological and the Quantum Worlds

Author

Paolo Salucci, Giampiero Esposito, Gaetano Lambiase, Emmanuele Battista, Micol Benetti, Donato Bini, Lumen Boco, Gauri Sharma, Valerio Bozza, Luca Buoninfante, Antonio Capolupo, Salvatore Capozziello, Giovanni Covone, Rocco D’Agostino, Mariafelicia De Laurentis, Ivan De Martino, Giulia De Somma, Elisabetta Di Grezia, Chiara Di Paolo, Lorenzo Fatibene, Viviana Gammaldi, Andrea Geralico, Lorenzo Ingoglia, Andrea Lapi, Giuseppe G. Luciano, Leonardo Mastrototaro, Adele Naddeo, Lara Pantoni, Luciano Petruzziello, Ester Piedipalumbo, Silvia Pietroni, Aniello Quaranta, Paolo Rota, Giuseppe Sarracino, Francesco Sorge, Antonio Stabile, Cosimo Stornaiolo, Antonio Tedesco, Riccardo Valdarnini, Stefano Viaggiu, and Andy A. V. Yunge

Subjects
dark matter, galaxies, nature of dark matter, beyond standard model, modification of general relativity, quantum gravity and cosmology, Physics, QC1-999
Abstract

In Cosmology and in Fundamental Physics there is a crucial question like: where the elusive substance that we call Dark Matter is hidden in the Universe and what is it made of? that, even after 40 years from the Vera Rubin seminal discovery [1] does not have a proper answer. Actually, the more we have investigated, the more this issue has become strongly entangled with aspects that go beyond the established Quantum Physics, the Standard Model of Elementary particles and the General Relativity and related to processes like the Inflation, the accelerated expansion of the Universe and High Energy Phenomena around compact objects. Even Quantum Gravity and very exotic Dark Matter particle candidates may play a role in framing the Dark Matter mystery that seems to be accomplice of new unknown Physics. Observations and experiments have clearly indicated that the above phenomenon cannot be considered as already theoretically framed, as hoped for decades. The Special Topic to which this review belongs wants to penetrate this newly realized mystery from different angles, including that of a contamination of different fields of Physics apparently unrelated. We show with the works of this ST that this contamination is able to guide us into the required new Physics. This review wants to provide a good number of these “paths or contamination” beyond/among the three worlds above; in most of the cases, the results presented here open a direct link with the multi-scale dark matter phenomenon, enlightening some of its important aspects. Also in the remaining cases, possible interesting contacts emerges. Finally, a very complete and accurate bibliography is provided to help the reader in navigating all these issues.

Published
2021
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7. Caustics in Gravitational Lensing by Mixed Binary Systems

Author

Valerio Bozza, Silvia Pietroni, and Chiara Melchiorre

Subjects
gravitational lensing, black holes, wormholes, galaxies, Elementary particle physics, QC793-793.5
Abstract

We investigated binary lenses with 1/rn potentials in the asymmetric case with two lenses with different indexes n and m. These kinds of potentials have been widely used in several contexts, ranging from galaxies with halos described by different power laws to lensing by wormholes or exotic matter. In this paper, we present a complete atlas of critical curves and caustics for mixed binaries, starting from the equal-strength case, and then exploring unequal-strength systems. We also calculate the transitions between all different topology regimes. Finally we find some useful analytic approximations for the wide binary case and for the extreme unequal-strength case.

Published
2020
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8. Physical properties of near-Earth asteroid (2102) Tantalus from multiwavelength observations

Author

Agata Rożek, Stephen C Lowry, Benjamin Rozitis, Lord R Dover, Patrick A Taylor, Anne Virkki, Simon F Green, Colin Snodgrass, Alan Fitzsimmons, Justyn Campbell-White, Sedighe Sajadian, Valerio Bozza, Martin J Burgdorf, Martin Dominik, R Figuera Jaimes, Tobias C Hinse, Markus Hundertmark, Uffe G Jørgensen, Penélope Longa-Peña, Markus Rabus, Sohrab Rahvar, Jesper Skottfelt, and John Southworth

Published
2022
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9. Four Sub-Jovian-Mass Planets Detected by High-Cadence Microlensing Surveys

Author

Cheongho Han, Doeon Kim, Andrew Gould, Andrzej Udalski, Ian A. Bond, Valerio Bozza, Youn Kil Jung, Michael D. Albrow, Sun-Ju Chung, Kyu-Ha Hwang, Yoon-Hyun Ryu, In-Gu Shin, Yossi Shvartzvald, Jennifer C. Yee, Weicheng Zang, Sang-Mok Cha, Dong-Jin Kim, Seung-Lee Kim, Chung-Uk Lee, Dong-Joo Lee, Yongseok Lee, Byeong-Gon Park, Richard W. Pogge, Przemek Mróz, Michał K. Szymański, Jan Skowron, Radosław Poleski, Igor Soszyński, Paweł Pietrukowicz, Szymon Kozłowski, Richard K. Barry, David P. Bennett, Aparna Bhattacharya, Gregory Olmschenk, and Stela Ishitani Silva

Subjects
Solar Physics, Astrophysics, Astronomy
Abstract

Aims. With the aim of finding short-term planetary signals, we investigated the data collected from current high-cadence microlensing surveys. Methods. From this investigation, we found four planetary systems with low planet-to-host mass ratios, including OGLE-2017-BLG- 1691L, KMT-2021-BLG-0320L, KMT-2021-BLG-1303L, and KMT-2021-BLG-1554L. Despite the short durations, ranging from a few hours to a couple of days, the planetary signals were clearly detected by the combined data of the lensing surveys. We found that three of the planetary systems have mass ratios on the order of 10−4 and the other has a mass ratio that is slightly greater than 10−3. Results. The estimated masses indicate that all discovered planets have sub-Jovian masses. The planet masses of KMT-2021-BLG- 0320Lb, KMT-2021-BLG-1303Lb, and KMT-2021-BLG-1554Lb correspond to ∼0.10, ∼0.38, and ∼0.12 times the mass of the Jupiter, and the mass of OGLE-2017-BLG-1691Lb corresponds to that of the Uranus. The estimated mass of the planet host KMT-2021-BLG- 1554L, Mhost ∼ 0.08 M⊙, corresponds to the boundary between a star and a brown dwarf. Besides this system, the host stars of the other planetary systems are low-mass stars with masses in the range of ∼[0.3–0.6] M⊙. The discoveries of the planets fully demonstrate the capability of the current high-cadence microlensing surveys in detecting low-mass planets.

Published
2022
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10. OGLE-2018-BLG-1185b: A Low-mass Microlensing Planet Orbiting a Low-mass Dwarf

Author

Iona Kondo, Jennifer C. Yee, David P. Bennett, Takahiro Sumi, Naoki Koshimoto, Ian A. Bond, Andrew Gould, Andrzej Udalski, Yossi Shvartzvald, Youn Kil Jung, Weicheng Zang, Valerio Bozza, Etienne Bachelet, Markus P. G. Hundertmark, Nicholas J. Rattenbury, F. Abe, R Barry, A. Bhattacharya, M. Donachie, A. Fukui, H. Fujii, Y. Hirao, S. Ishitani Silva, Y. Itow, R. Kirikawa, M. C. A. Li, Y. Matsubara, S. Miyazaki, Y. Muraki, G. Olmschenk, C. Ranc, Y. Satoh, H. Shoji, D. Suzuki, Y. Tanaka, K. Ulaczyk, P. J. Tristram, T. Yamawaki, A Yonehara, R. Poleski, J. Skowron, M. K. Szymański, K. A. Rybicki, I. Soszynski, S. Kozłowski, P. Pietrukowicz, P. Iwanek, M. Wrona, M. D. Albrow, J. Wambsganss, S. J. Chung, C. Han, K. H. Hwang, H. W. Kim, I. G. Shin, S. M. Cha, D. J. Kim, S. L. Kim, C. U. Lee, D. J. Lee, Y. Lee, B. G. Park, R. W. Pogge, Y.-H. Ryu, C. A. Beichman, G Bryden, S. Calchi Novati, S. Carey, B. S. Gaudi, C. B. Henderson, W. Zhu, D. Maoz, M. T. Penny, M. Dominik, U. G. Jorgensen, P. Longa-Pena, N. Peixinho, S. Sajadian, J. Skottfelt, C. Snodgrass, J. Tregloan-Reed, M. J. Burgdorf, J. Campbell-White, S. Dib, Y. I. Fujii, E. Khalouei, S. Rahvar, M. Rabus, J. Southworth, Y. Tsapras, R. A. Street, D. M. Bramich, A. Cassan, K. Horne, S. Mao, A. Saha, and P. Mroz

Subjects
Astronomy
Abstract

We report an analysis of the planetary microlensing event OGLE-2018-BLG-1185, which was observed by a large number of ground-based telescopes and by the Spitzer Space Telescope. The ground-based light curve indicates a low planet–host star mass ratio ofq=(6.9±0.2)×10−5, which is near the peak of the wide-orbit exoplanet mass-ratio distribution. We estimate the host star and planet masses with a Bayesian analysis using the measured angular Einstein radius under the assumption that stars of all masses have an equal probability of hosting the planet. The flux variation observed by Spitzer is marginal, but still places a constraint on the microlens parallax. Imposing a conservative constraint that this flux variation should beΔfSpz<4 instrumental flux units yields a host mass of=-+MM0.37 host 0.210.35 and a planet mass of =-+ÅmM8.4p4.77.9. A Bayesian analysis including the full parallax constraint from Spitzer suggests smaller host star and planet masses of =-+MM0.091 host 0.0180.064 and =-+ÅmM2.1p0.41.5, respectively. Future high-resolution imaging observations with the Hubble Space Telescope or Extremely Large Telescope could distinguish between these two scenarios and help reveal the planetary system properties in more detail.

Published
2021
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11. Candidate Brown-dwarf Microlensing Events with Very Short Timescales and Small Angular Einstein Radii

Author

Cheongho Han, Chung Uk Lee, Andrzej Udalski, Andrew Gould, Ian A. Bond, Valerio Bozza, Michael D. Albrow, Sun Ju Chung, Kyu Ha Hwang, Youn Kil Jung, Yoon-Hyun Ryu, In Gu Shin, Yossi Shvartzvald, Jennifer C. Yee, Weicheng Zang, Sang Mok Cha, Dong-Jin Kim, Hyoun Woo Kim, Seung Lee Kim, Dong-Joo Lee, Yongseok Lee, Byeong Gon Park, Richard W. Pogge, M. James Jee, Doeon Kim, Przemek Mroz, Michal K. Szymański, Jan Skowron, Radek Poleski, Igor Soszynski, Pawel Pietrukowicz, Szymon Kozłowski, Krzysztof Ulaczyk, Krzysztof A. Rybicki, Patryk Iwanek, Marcin Wrona, Fumio Abe, Barry Richardson, David P. Bennett, Aparna Bhattacharya, Martin Donachie, Hirosane Fujii, Akihiko Fukui, Yoshitaka Itow, Yuki Hirao, Yuhei Kamei, Iona Kondo, Naoki Koshimoto, Man Cheung Alex Li, Yutaka Matsubara, Yasushi Muraki, Shota Miyazaki, Masayuki Nagakane, Clement Ranc, Nicholas J. Rattenbury, Yuki Satoh, Hikaru Shoji, Haruno Suematsu, Denis J. Sullivan, Takahiro Sumi, Daisuke Suzuki, Paul J. Tristram, Takeharu Yamakawa, Tsubasa Yamawaki, and and Atsunori Yonehara

Subjects
Astronomy, Astrophysics
Abstract

Short-timescale microlensing events are likely to be produced by substellar brown dwarfs (BDs), but it is difficult to securely identify BD lenses based on only event timescales because short-timescale events can also be produced by stellar lenses with high relative lens-source proper motions. In this paper, we report three strong candidate BD-lens events found from the search for lensing events not only with short timescales (t(E) ≲ 6 days) but also with very small angular Einstein radii (θ(E) ≲ 0.05 mas) among the events that have been found in the 2016–2019 observing seasons. These events include MOA-2017-BLG-147, MOA-2017-BLG-241, and MOA-2019-BLG-256, in which the first two events are produced by single lenses and the last event is produced by a binary lens. From the Monte Carlo simulations of Galactic events conducted with the combined t(E) and θ(E) constraint, it is estimated that the lens masses of the individual events are 0.051 (sup +0.100, sub -0.027) M(ʘ), 0.044 (sup +0.090, sub -0.023) M(ʘ), and 0.046 (sup +0.067, sub -0.023) M(ʘ)/0.038 (sup +0.056, sub -0.019) M(ʘ) and the probability of the lens mass smaller than the lower limit of stars is ~80% for all events. We point out that routine lens mass measurements of short-timescale lensing events require survey-mode space-based observations.

Published
2020
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12. Spitzer Microlensing Parallax Reveals Two Isolated Stars in the Galactic Bulge

Author

Weicheng Zang, Yossi Shvartzvald, Tianshu Wang, Andrzej Udalski, Chung-Uk Lee, Takahiro Sumi, Jesper Skottfelt, Shun-Sheng Li, Shude Mao, Wei Zhu, Jennifer C. Yee, Sebastiano Calchi Novati, Charles A. Beichman, Geoffery Bryden, Sean Carey, B. Scott Gaudi, Calen B. Henderson, Przemek Mróz, Jan Skowron, Radoslaw Poleski, Michał K. Szymański, Igor Soszyński, Paweł Pietrukowicz, Szymon Kozłowski, Krzysztof Ulaczyk, Krzysztof A. Rybicki, Patryk Iwanek, Etienne Bachelet, Grant Christie, Jonathan Green, Steve Hennerley, Dan Maoz, Tim Natusch, Richard W. Pogge, Rachel A. Street, Yiannis Tsapras, Michael D. Albrow, Sun-Ju Chung, Andrew Gould, Cheongho Han, Kyu-Ha Hwang, Youn Kil Jung, Yoon-Hyun Ryu, In-Gu Shin, Sang-Mok Cha, Dong-Jin Kim, Hyoun-Woo Kim, Seung-Lee Kim, Dong-Joo Lee, Yongseok Lee, Byeong-Gon Park, Ian A. Bond, Fumio Abe, Richard K Barry, David P Bennett, Aparna Bhattacharya, Martin Donachie, Akihiko Fukui, Yuki Hirao, Yoshitaka Itow, Iona Kondo, Naoki Koshimoto, Man Cheung Alex Li, Yutaka Matsubara, Yasushi Muraki, Shota Miyazaki, Masayuki Nagakane, Clement Ranc, Nicholas J. Rattenbury, Haruno Suematsu, Denis J. Sullivan, Daisuke Suzuki, Paul J. Tristram, Atsunori Yonehara, Martin Dominik, Markus Hundertmark, Uffe G. Jørgensen, Sohrab Rahvar, Sedighe Sajadian, Colin Snodgrass, Valerio Bozza, Martin J. Burgdorf, Daniel F. Evans, R. Figuera Jaimes, Yuri I. Fujii, Luigi Mancini, Penelope Longa-Peña, Christiane Helling, Nuno Peixinho, Markus Rabus, John Southworth, Eduardo Unda-Sanzana, and Carolina von Essen

Subjects
Astrophysics, Astronomy
Abstract

We report the mass and distance measurements of two single-lens events from the 2017 Spitzer microlensing campaign. The ground-based observations yield the detection of finite-source effects, and the microlens parallaxes are derived from the joint analysis of ground-based observations and Spitzer observations. We find that the lens of OGLE-2017-BLG-1254 is a 0.60 ± 0.03 M⊙ star with D(LS) = 0.53 ± 0.11 kpc, where D(LS) is the distance between the lens and the source. The second event, OGLE-2017-BLG-1161, is subject to the known satellite parallax degeneracy, and thus is either a 0.51(sup +0.12, sub 3-0.10)M⊙ star with D(LS) = 0.40 ± 0.12 kpc or a 0.38(sup +0.13, sub -0.12) M⊙ star with D(LS) = 0.53 ± 0.19 kpc. Both of the lenses are therefore isolated stars in the Galactic bulge. By comparing the mass and distance distributions of the eight published Spitzer finite-source events with the expectations from a Galactic model, we find that the Spitzer sample is in agreement with the probability of finite-source effects occurring in single-lens events.

Published
2020
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13. OGLE-2013-BLG-0911Lb: A Secondary on the Brown-dwarf Planet Boundary around an M Dwarf

Author

Shota Miyazaki, Takahiro Sumi, David P. Bennett, Andrzej Udalski, Yossi Shvartzvald, Rachel Street, Valerio Bozza, Jennifer C. Yee, Ian A. Bond, Nicholas Rattenbury, Naoki Koshimoto, Daisuke Suzuki, Akihiko Fukui, F. Abe, A. Bhattacharya, R. Barry, M. Donachie, H. Fujii, Y. Hirao, Y. Itow, Y. Kamei, I. Kondo, M. C. A. Li, C. H. Ling, Y. Matsubara, T. Matsuo, Y. Muraki, M. Nagakane, K. Ohnishi, C Ranc, T. Saito1, A. Sharan, H. Shibai, H. Suematsu, D. J. Sullivan, P. J. Tristram, T. Yamakawa, A. Yonehara, J. Skowron, R. Poleski, P. Mróz, M. K. Szymański, I. Soszyński, P. Pietrukowicz, S. KozŁowski, K. Ulaczyk, Ł. Wyrzykowski, Matan Friedmann, Shai Kaspi, Dan Maoz, M. Albrow, G. Christie, D. L. DePoy, A. Gal-Yam, A. Gould, C.-U. Lee, I. Manulis, J. McCormick, T. Natusch, H. Ngan, R. W. Pogge, I. Porritt, Y. Tsapras, E. Bachelet, M. P. G. Hundertmark, M. Dominik, D. M. Bramich, A. Cassan, R. Figuera Jaimes, K. Horne, R. Schmidt, C. Snodgrass, J. Wambsganss, I. A. Steele, J. Menzies, S. Mao, U. G. Jørgensen, M. J. Burgdorf, S. Ciceri, S. Calchi Novati, G. D’Ago, D. F. Evans, T. C. Hinse, N. Kains, E. Kerins, H. Korhonen, L. Mancini, A. Popovas, M. Rabus, S. Rahvar, G. Scarpetta, J. Skottfelt, J. Southworth, N. Peixinho, and P. Verma

Subjects
Astrophysics, Astronomy
Abstract

We present the analysis of the binary-lens microlensing event OGLE-2013-BLG-0911. The best-fit solutions indicate the binary mass ratio of q 0.03, which differs from that reported in Shvartzvald et al. The event suffers from the well-known close/wide degeneracy, resulting in two groups of solutions for the projected separation normalized by the Einstein radius of s ~ 0.15 or s ~ 7. The finite source and the parallax observations allow us to measure the lens physical parameters. The lens system is an M dwarf orbited by a massive Jupiter companion at very close (M(host) = 0.30(sup +0.08, sub -0.06)Mʘ, M(comp) = 10.1 (sup +2.9, sub -2.2 M(jup), a(exp) = 0.40 (sup +0.05, sub -0.40)au) or wide (M(host) = 0.28 (sup +0.10, sub -0.80)Mʘ, M(comp) = 9.9 (sup +3.8, sub -3.5)M(jup), a(exp) = 18.0 (sup +3.2, sub -3.2)au) separation. Although the mass ratio is slightly above the planet-brown dwarf (BD) mass-ratio boundary of q = 0.03, which is generally used, the median physical mass of the companion is slightly below the planet-BD mass boundary of 13M(Jup). It is likely that the formation mechanisms for BDs and planets are different and the objects near the boundaries could have been formed by either mechanism. It is important to probe the distribution of such companions with masses of ~13M(Jup) in order to statistically constrain the formation theories for both BDs and massive planets. In particular, the microlensing method is able to probe the distribution around low-mass M dwarfs and even BDs, which is challenging for other exoplanet detection methods.

Published
2020
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14. MOA-bin-29b: A Microlensing Gas-giant Planet Orbiting a Low-mass Host Star

Author

Iona Kondo, Takahiro Sumi, David P Bennett, Andrzej Udalski, Ian A. Bond, Nicholas J. Rattenbury, Valerio Bozza, Yuki Hirao, Daisuke Suzuki, Naoki Koshimoto, Masayuki Nagakane, Shota Miyazaki, F. Abe, R Barry, A. Bhattacharya, M. Donachie, A. Fukui, H. Fujii, Y. Itow, Y. Kamei, M. C. A. Li, Y. Matsubara, T. Matsuo, Y. Muraki, Clement Ranc, H. Shibai, H. Suematsu, D. J. Sullivan, P. J. Tristram, T. Yamakawa, A. Yonehara, P. Mroz, M. K. Szymański, I. Soszyński, and and K. Ulaczyk

Subjects
Astrophysics, Astronomy
Abstract

We report the discovery of a gas-giant planet orbiting a low-mass host star in the microlensing event MOA-bin-29 that occurred in 2006. We find five degenerate solutions with the planet/host-star mass ratio of q ∼ 10(exp−2). The Einstein radius crossing time of all models are relatively short (∼4–7 days), which indicates that the mass of host star is likely low. The measured lens-source proper motion is 5–9 mas/yr depending on the models. Since only finite source effects are detected, we conduct a Bayesian analysis in order to obtain the posterior probability distribution of the lens physical properties. As a result, we find the lens system is likely to be a gas-giant orbiting a brown dwarf or a very late M-dwarf in the Galactic bulge. The probability distributions of the physical parameters for the five degenerate models are consistent within the range of error. By combining these probability distributions, we conclude that the lens system is a gas giant with a mass of M(p)= 0.63(sub +1.13, sub 0.39) M(Jup) orbiting a brown dwarf with a mass of M(h)= 0.06 (sup +0.11, sub -0.04) M(ʘ) at a projected star–planet separation of r⊥ = 0.53(sup +0.89, sub -0.18)au . The lens distance is D(L)= 6.89(sup +1.19, sub -1.19) kpc, i.e., likely within the Galactic bulge.

Published
2019
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15. OGLE-2015-BLG-1649Lb: A Gas Giant Planet around a Low-mass Dwarf

Author

M. Nagakane, Chien-Hsiu Lee, N. Koshimoto, Daisuke Suzuki, A. Udalski, J. P. Beaulieu, T. Sumi, D. P. Bennett, I. A. Bond, N. Rattenbury, E. Bachelet, Martin Dominik, F. Abe, R. K. Barry, A. Bhattacharya, M. Donachie, H. Fujii, A. Fukui, Y. Hirao, Y Itow, Y. Kamei, Iona Kondo, M. C. A. Li, Y. Matsubara, T. Matsuo, Shota Miyazaki, Y. Muraki, C. Ranc, H. Shibai, H. Suematsu, D. J. Sullivan, P. J. Tristram, T. Yamakawa, A. Yonehara, Przemek Mroz, Radoslaw Poleski, J. Skowron, M. K. Szymański, I. Soszyński, Pawel Pietrukowicz, Szymon Kozłowski, Krzysztof Ulaczyk, D. M. Bramich, A. Cassan, R. Figuera Jaimes, K. Horne, M. Hundertmark, Shude Mao, J. Menzies, R. Schmidt, Colin Snodgrass, Iain Steele, Rachel Street, Yiannis Tsapras, Joachim Wambsganss, U. G. Jørgensen, Valerio Bozza, P. Longã, Nuno Peixinho, J. Skottfelt, J. Southworth, M. I. Andersen, M. J. Burgdorf, Giuseppe D'Ago, Daniel Evans, Tobias Cornelius Hinse, H. Korhonen, Markus Rabus, and Sohrab Rahvar

Subjects
Astronomy, Astrophysics
Abstract

We report the discovery of an exoplanet from the analysis of the gravitational microlensing event OGLE-2015-BLG-1649 that challenges the core accretion model of planet formation and appears to support the disk instability model. The planet/host-star mass ratio is q = 7.2 × 10^(−3) and the projected separation normalized to the angular Einstein radius is s = 0.9. We conducted high-resolution follow-up observations using the Infrared Camera and Spectrograph (IRCS) camera on the Subaru telescope and are able to place an upper limit on the lens flux. From these measurements we are able to exclude all host stars greater than or equal in mass to a G-type dwarf. We conducted a Bayesian analysis with these new flux constraints included as priors resulting in estimates of the masses of the host star and planet. These are ML = 0.34 ± 0.19 M⊙ and M(p)=2.5 (+1.5,-1.4) M(Jup), respectively. The distance to the system is D(L)=4.23 (+1.51, -1.64) kpc. The projected star–planet separation is a(┴)=2.07 (+0.65,-0.77) au. The estimated relative lens-source proper motion, ~7.1 mas/yr, is fairly high and thus the lens can be better constrained if additional follow-up observations are conducted several years after the event.

Published
2019
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16. OGLE-2018-BLG-1011Lb,c: Microlensing Planetary System with Two Giant Planets Orbiting a Low-mass Star

Author

Cheongho Han, David P Bennett, Andrzej Udalski, Andrew Gould, Ian A. Bond, Yossi Shvartzvald, Kay-Sebastian Nikolaus, Markus Hundertmark, Valerio Bozza, Arnaud Cassan, Yuki Hirao, Etienne Bachelet, Pascal Fouqué, Michael D. Albrow, Sun-Ju Chung, Kyeongsoo Hong, Kyu-Ha Hwang, Chung-Uk Lee, Yoon-Hyun Ryu, In-Gu Shin, Jennifer C. Yee, Youn Kil Jung, Sang-Mok Cha, Doeon Kim, Dong-Jin Kim, Hyoun-Woo Kim, Seung-Lee Kim, Dong-Joo Lee, Yongseok Lee, Byeong-Gon Park, Richard W. Pogge, Przemek Mróz, Michał K. Szymański, Jan Skowron, Radek Poleski, Igor Soszyński, Paweł Pietrukowicz, Szymon Kozłowski, Krzysztof Ulaczyk, Krzysztof A. Rybicki, Patryk Iwanek, Marcin Wrona, Fumio Abe, Richard Barry, Aparna Bhattacharya, Martin Donachie, Akihiko Fukui, Yoshitaka Itow, Kohei Kawasaki, Iona Kondo, Naoki Koshimoto, Man Cheung Alex Li, Yutaka Matsubara, Yasushi Muraki, Shota Miyazaki, Masayuki Nagakane, Clement Ranc, Nicholas J. Rattenbury, Haruno Suematsu, Denis J. Sullivan, Takahiro Sumi, Daisuke Suzuki, Paul J. Tristram, Atsunori Yonehara, Shude Mao, Tianshu Wang, Weicheng Zang, Wei Zhu, Matthew T. Penny, Charles A. Beichman, Geoffery Bryden, Sebastiano Calchi Novati, B. Scott Gaudi, Calen B. Henderson, Savannah Jacklin, and Keivan G. Stassun

Subjects
Astrophysics, Astronomy
Abstract

We report a multiplanetary system found from the analysis of microlensing event OGLE-2018-BLG-1011, for which the light curve exhibits a double-bump anomaly around the peak. We find that the anomaly cannot be fully explained by the binary-lens or binary-source interpretations and its description requires the introduction of an additional lens component. The 3L1S (three lens components and a single source) modeling yields three sets of solutions, in which one set of solutions indicates that the lens is a planetary system in a binary, while the other two sets imply that the lens is a multiplanetary system. By investigating the fits of the individual models to the detailed light curve structure, we find that the multiple-planet solution with planet-to-host mass ratios ∼9.5 X 10(exp −3) and ∼15 X 10(eap −3) are favored over the other solutions. From the Bayesian analysis, we find that the lens is composed of two planets with masses 1.8 (sup +3.4, sub -1.1) M(J) and 2.8 (sup +5.8, sub -1.7) M(J) around a host with a mass 0.18 (sup +0.33,sub - 0.10) M(ʘ) and located at a distance 7.1(sup +1.1, sub -1.5) kpc. The estimated distance indicates that the lens is the farthest system among the known multiplanetary systems. The projected planet–host separations are a(⊥,2) = 1.8 (sup +2.1, sub -1.5)au (0.8 (sup +0.9,sub -0.6 au) and a(⊥,3) = 0.8 (sup +0.9, sub -0.6)au , where the values of a(⊥,2) inside and outside the parenthesis are the separations corresponding to the two degenerate solutions, indicating that both planets are located beyond the snow line of the host, as with the other four multiplanetary systems previously found by microlensing.

Published
2019
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17. Spectroscopic Mass and Host-star Metallicity Measurements for Newly Discovered Microlensing Planet OGLE-2018-BLG-0740Lb

Author

Cheongho Han, Jennifer C. Yee, Andrzej Udalski, Ian A. Bond, Valerio Bozza, Arnaud Cassan, Yuki Hirao, Subo Dong, Juna A. Kollmeier, Nidia Morrell, Konstantina Boutsia, Michael D. Albrow, Sun-Ju Chung, Andrew Gould, Kyu-Ha Hwang, Chung-Uk Lee, Yoon-Hyun Ryu, In-Gu Shin, Yossi Shvartzvald, Youn Kil Jung, Doeon Kim, Woong-Tae Kim, Sang-Mok Cha, Dong-Jin Kim, Hyoun-Woo Kim, Kyeongsoo Hong, Seung-Lee Kim, Dong-Joo Lee, Yongseok Lee, Byeong-Gon Park, Richard W. Pogge, Weicheng Zang, Przemek Mróz, Michał K. Szymański, Jan Skowron, Radek Poleski, Igor Soszyński, Paweł Pietrukowicz, Szymon Kozłowski, Krzysztof Ulaczyk, Krzysztof A. Rybicki, Patryk Iwanek, Marcin Wrona, Fumio Abe, Richard Barry, David P Bennett, Aparna Bhattacharya, Martin Donachie, Akihiko Fukui, Yoshitaka Itow, Kohei Kawasaki, Iona Kondo, Naoki Koshimoto, Man Cheung Alex Li, Yutaka Matsubara, Yasushi Muraki, Shota Miyazaki, Masayuki Nagakane, Clement Ranc, Nicholas J. Rattenbury, Haruno Suematsu, Denis J. Sullivan, Takahiro Sumi, Daisuke Suzuki, Paul J. Tristram, and Atsunori Yonehara

Subjects
Astrophysics, Astronomy
Abstract

We report the discovery of the microlensing planet OGLE-2018-BLG-0740Lb. The planet is detected with a very strong signal of Δχ(exp 2) ∼ 4630, but the interpretation of the signal suffers from two types of degeneracies. One type is caused by the previously known close/wide degeneracy, and the other is caused by an ambiguity between two solutions, in which one solution requires the incorporation of finite-source effects, while the other solution is consistent with a point-source interpretation. Although difficult to be firmly resolved based on only the photometric data, the degeneracy is resolved in strong favor of the point-source solution with the additional external information obtained from astrometric and spectroscopic observations. The small astrometric offset between the source and baseline object supports that the blend is the lens and this interpretation is further secured by the consistency of the spectroscopic distance estimate of the blend with the lensing parameters of the point-source solution. The estimated mass of the host is 1.0 ± 0.1 M(ʘ) and the mass of the planet is 4.5 ± 0.6 M(J) (close solution) or 4.8 ± 0.6 M(J) (wide solution) and the lens is located at a distance of 3.2 ± 0.5 kpc. The bright nature of the lens, with I ∼ 17.1 (V ∼ 18.2), combined with its dominance of the observed flux suggest that radialvelocity (RV) follow-up observations of the lens can be done using high-resolution spectrometers mounted on large telescopes, e.g., Very Large Telescope/ESPRESSO, and this can potentially not only measure the period and eccentricity of the planet but also probe for close-in planets. We estimate that the expected RV amplitude would be ~60 sin i m/s.

Published
2019
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18. OGLE-2018-BLG-0022: First Prediction of an Astrometric Microlensing Signal from a Photometric Microlensing Event

Author

Cheongho Han, Ian A. Bond, Andrzej Udalski, Andrew Gould, Valerio Bozza, Yuki Hirao, Arnaud Cassan, Michael D. Albrow, Sun-Ju Chung, Kyu-Ha Hwang, Chung-Uk Lee, Yoon-Hyun Ryu, In-Gu Shin, Yossi Shvartzvald, Jennifer C. Yee, Youn Kil Jung, Doeon Kim, Woong-Tae Kim, Sang-Mok Cha, Dong-Jin Kim, Hyoun-Woo Kim, Seung-Lee Kim, Dong-Joo Lee, Yongseok Lee, Byeong-Gon Park, Richard W. Pogge, Weicheng Zang, Fumio Abe, Richard Barry, David P. Bennett, Aparna Bhattacharya, Martin Donachie, Akihiko Fukui, Yoshitaka Itow, Kohei Kawasaki, Iona Kondo, Naoki Koshimoto, Man Cheung Alex Li, Yutaka Matsubara, Yasushi Muraki, Shota Miyazaki, Masayuki Nagakane, Clement Ranc, Nicholas J. Rattenbury, Haruno Suematsu, Denis J. Sullivan, Takahiro Sumi, Daisuke Suzuki, Paul J. Tristram, Atsunori Yonehara, Przemek Mroz, Michal K. Szymanski, Jan Skowron, Radek Poleski, Igor Soszynski, Pawel Pietrukowicz, Szymon Kozłowski, Krzysztof Ulaczyk, Krzysztof A. Rybicki, Patryk Iwanek, Marcin Wrona, Charles A. Beichman, Geoffery Bryden, Sean Carey, B. Scott Gaudi, Calen B. Henderson, and Sebastiano Calchi Novatil

Subjects
Astrophysics, Astronomy
Abstract

In this work, we present the analysis of the binary microlensing event OGLE-2018-BLG-0022 that is detected toward the Galactic bulge field. The dense and continuous coverage with the high-quality photometry data from ground-based observations combined with the space-based Spitzer observations of this long timescale event enables us to uniquely determine the masses M 1 = 0.40 ± 0.05 M ⊙ and M 2 = 0.13 ± 0.01 M ⊙ of the individual lens components. Because the lens-source relative parallax and the vector lens-source relative proper motion are unambiguously determined, we can likewise unambiguously predict the astrometric offset between the light centroid of the magnified images (as observed by the Gaia satellite) and the true position of the source. This prediction can be tested when the individual-epoch Gaia astrometric measurements are released.

Published
2019
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19. KELT-22Ab: A Massive, Short-Period Hot Jupiter Transiting a Near-solar Twin

Author

Knicole Colon, David R Ciardi, Jonathan Labadie-Bartz, Joseph E. Rodriguez, Keivan G. Stassun, Kaloyan Penev, Marshall C. Johnson, B. Scott Gaudi, Knicole D. Colón, Allyson Bieryla, David W. Latham, Joshua Pepper, Karen A. Collins, Phil Evans, Howard Relles, Robert J. Siverd, Joao Bento, Xinyu Yao, Chris Stockdale, Thiam-Guan Tan, George Zhou, Jason D. Eastman, Michael D. Albrow, Daniel Bayliss, Thomas G. Beatty, Perry Berlind, Valerio Bozza, Michael L. Calkins, David H. Cohen, Ivan A. Curtis, Gilbert A. Esquerdo, Dax Feliz, Benjamin J Fulton, Joao Gregorio, David James, Eric L. N. Jensen, John A. Johnson, Samson A. Johnson, Michael D. Joner, David Kasper, John F. Kielkopf, Rudolf B. Kuhn, Michael B. Lund, Amber Malpas, Mark Manner, Nate McCrady, Kim K. McLeod, Thomas E. Oberst, Matthew T. Penny, Phillip A. Reed, David H. Sliski, Denise C. Stephens, Daniel J. Stevens, Jr, Robert A. Wittenmyer, J. T. Wright, and Roberto Zambelli

Subjects
Lunar And Planetary Science And Exploration, Space Sciences (General)
Abstract

We present the discovery of KELT-22Ab, a hot Jupiter from the KELT-South survey. KELT-22Ab transits the moderately bright (V11.1) Sun-like G2V star TYC 7518-468-1. The planet has an orbital period of P = 1.3866529 0.0000027 days, a radius of = -R 1.285+ R P 0.071 J 0.12 , and a relatively large mass of = - M 3.47+ M P 0.14 J 0.15 . The star has = - + R 1.099 0.046 R 0.079 , = - + M 1.092 0.041 M 0.045 , = - T 5767+ eff 49 50 K, = - log g 4.393+0.0600.039 (cgs), and [m/H]=+ -0.259+0.0830.085; thus other than its slightly super-solar metallicity, it appears to be a near-solar twin. Surprisingly, KELT-22A exhibits kinematics and a Galactic orbit that are somewhat atypical for thin-disk stars. Nevertheless, the star is rotating rapidly for its estimated age, and shows evidence of chromospheric activity. Imaging reveals a slightly fainter companion to KELT-22A that is likely bound, with a projected separation of 6″ (∼1400 au). In addition to the orbital motion caused by the transiting planet, we detect a possible linear trend in the radial velocity of KELT-22A, suggesting the presence of another relatively nearby body that is perhaps non-stellar. KELT-22Ab is highly irradiated (as a consequence of the small semimajor axis of a R = 4.97), and is mildly inflated. At such small separations, tidal forces become significant. The configuration of this system is optimal for measuring the rate of tidal dissipation within the host star. Our models predict that, due to tidal forces, the semimajor axis is decreasing rapidly, and KELT-22Ab is predicted to spiral into the star within the next Gyr.

Published
2019
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20. Brown-dwarf companions in microlensing binaries detected during the 2016--2018 seasons

Author

Cheongho Han, Yoon-Hyun Ryu, In-Gu Shin, Youn Kil Jung, Doeon Kim, Yuki Hirao, Valerio Bozza, Michael D. Albrow, Weicheng Zang, Andrzej Udalski, Ian A. Bond, Sun-Ju Chung, Andrew Gould, Kyu-Ha Hwang, Yossi Shvartzvald, Hongjing Yang, Sang-Mok Cha, Dong-Jin Kim, Hyoun-Woo Kim, Seung-Lee Kim, Chung-Uk Lee, Dong-Joo Lee, Jennifer C. Yee, Yongseok Lee, Byeong-Gon Park, Richard W. Pogge, Przemek Mróz, Michał K. Szymański, Jan Skowron, Radek Poleski, Igor Soszyński, Paweł Pietrukowicz, Szymon Kozłowski, Krzysztof Ulaczyk, Krzysztof A. Rybicki, Patryk Iwanek, Marcin Wrona, Fumio Abe, Richard Barry, David P. Bennett, Aparna Bhattacharya, Hirosame Fujii, Akihiko Fukui, Stela Ishitani Silva, Rintaro Kirikawa, Iona Kondo, Naoki Koshimoto, Yutaka Matsubara, Sho Matsumoto, Shota Miyazaki, Yasushi Muraki, Arisa Okamura, Greg Olmschenk, Clément Ranc, Nicholas J. Rattenbury, Yuki Satoh, Takahiro Sumi, Daisuke Suzuki, Taiga Toda, Paul J. Tristram, Aikaterini Vandorou, Hibiki Yama, and Yoshitaka Itow

Subjects
Earth and Planetary Astrophysics (astro-ph.EP), Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), FOS: Physical sciences, gravitational lensing: micro, brown dwarfs, Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies, Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics - Earth and Planetary Astrophysics
Abstract

With the aim of finding microlensing binaries containing brown-dwarf (BD) companions, we investigate the microlensing survey data collected during the 2016--2018 seasons. For this purpose, we first conducted modeling of lensing events with light curves exhibiting anomaly features that are likely to be produced by binary lenses. We then sorted out BD-companion binary-lens events by applying the criterion that the companion-to-primary mass ratio is $q \lesssim 0.1$. From this procedure, we identify 6 binaries with candidate BD companions, including OGLE-2016-BLG-0890L, MOA-2017-BLG-477L, OGLE-2017-BLG-0614L, KMT-2018-BLG-0357L, OGLE-2018-BLG-1489L, and OGLE-2018-BLG-0360L. We estimate the masses of the binary companions by conducting Bayesian analyses using the observables of the individual lensing events. According to the Bayesian estimation of the lens masses, the probabilities for the lens companions of the events OGLE-2016-BLG-0890, OGLE-2017-BLG-0614, OGLE-2018-BLG-1489, and OGLE-2018-BLG-0360 to be in the BD mass regime are very high with $P_{\rm BD}> 80\%$. For MOA-2017-BLG-477 and KMT-2018-BLG-0357, the probabilities are relatively low with $P_{\rm BD}=61\%$ and 69\%, respectively., 11 pages, 10 figures, 10 tables

Published
2022

21. Physical properties of near-Earth asteroid (2102) Tantalus from multi-wavelength observations

Author

Agata Rożek, Stephen C Lowry, Benjamin Rozitis, Lord R Dover, Patrick A Taylor, Anne Virkki, Simon F Green, Colin Snodgrass, Alan Fitzsimmons, Justyn Campbell-White, Sedighe Sajadian, Valerio Bozza, Martin J Burgdorf, Martin Dominik, R Figuera Jaimes, Tobias C Hinse, Markus Hundertmark, Uffe G Jørgensen, Penélope Longa-Peña, Markus Rabus, Sohrab Rahvar, Jesper Skottfelt, John Southworth, University of St Andrews. School of Physics and Astronomy, University of St Andrews. St Andrews Centre for Exoplanet Science, Particle Physics and Astrophysics, and Department of Physics

Subjects
observational [methods], FOS: Physical sciences, techniques: radar astronomy, ACCELERATION, Q1, asteroids: individual: (2102) Tantalus, individual: (2102) Tantalus [minor planets, asteroids], photometric [techniques], techniques: photometric, minor planets, asteroids: individual: (2102) Tantalus, methods: observational, QB460, RADAR SURVEY, YARKOVSKY, QB Astronomy, QC, QB, Earth and Planetary Astrophysics (astro-ph.EP), YORP, Minor planets, Astronomy and Astrophysics, 3rd-DAS, PLANETARY SURFACES, 115 Astronomy, Space science, STATE, MODEL, QC Physics, radar astronomy [techniques], Space and Planetary Science, minor planets, ROTATION, OBJECTS, individual: (2012) Tantalus [Asteroids], Astrophysics::Earth and Planetary Astrophysics, SPIN-UP, Astrophysics - Earth and Planetary Astrophysics
Abstract

Between 2010 and 2017 we have collected new optical and radar observations of the potentially hazardous asteroid (2102)~Tantalus from the ESO NTT and Danish telescopes at the La Silla Observatory and from the Arecibo planetary radar. The object appears to be nearly spherical, showing a low amplitude light-curve variation and limited large-scale features in the radar images. The spin-state is difficult to constrain with the available data; including a certain light-curve subset significantly changes the spin-state estimates, and the uncertainties on period determination are significant. Constraining any change in rotation rate was not possible, despite decades of observations. The convex lightcurve-inversion model, with rotational pole at ${\lambda}=210{\pm}41${\deg} and ${\beta}=-30{\pm}35${\deg}, is more flattened than the two models reconstructed by including radar observations: with prograde (${\lambda}=36{\pm}23${\deg}, ${\beta}=30{\pm}15${\deg}), and with retrograde rotation mode (${\lambda}=180{\pm}24${\deg}, ${\beta}=-30{\pm}16${\deg}). Using data from WISE we were able to determine that the prograde model produces the best agreement in size determination between radar and thermophysical modelling. Radar measurements indicate possible variation in surface properties, suggesting one side might have lower radar albedo and be rougher at centimetre-to-decimetre scale than the other. However, further observations are needed to confirm this. Thermophysical analysis indicates a surface covered in fine-grained regolith, consistent with radar albedo and polarisation ratio measurements. Finally, geophysical investigation of the spin-stability of Tantalus shows that it could be exceeding its critical spin-rate via cohesive forces., Comment: Main paper: 14 pages and 12 figure, Appendix: 13 pages and 12 figues

Published
2022

22. Large-scale changes of the cloud coverage in the ϵ Indi Ba and Bb system

Author

Yuri I. Fujii, Valerio Bozza, Jesper Skottfelt, Alexander Scholz, Lauri K. Haikala, Penélope Longa-Peña, James A. Hitchcock, Sohrab Rahvar, Th. Henning, Roberto Figuera Jaimes, Sedighe Sajadian, Christiane Helling, M. Hundertmark, Martin Dominik, Tobias C. Hinse, John Southworth, C. von Essen, Stephen C. Lowry, Martin Burgdorf, Colin Snodgrass, L. Mancini, J. Campbell-White, U. G. Jørgensen, M. Rabus, G. Hodosán, European Research Council, University of St Andrews. School of Physics and Astronomy, and University of St Andrews. St Andrews Centre for Exoplanet Science

Subjects
Brightness, astro-ph.SR, 010504 meteorology & atmospheric sciences, Brown dwarf, FOS: Physical sciences, Binary number, Scale (descriptive set theory), Astrophysics, individual: ϵ Indi Ba [Stars], DWARF, 01 natural sciences, techniques: photometric, SEARCH, QB460, 0103 physical sciences, PHOTOMETRY, QB Astronomy, TEMPERATURE, 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), QC, QB, 0105 earth and related environmental sciences, Earth and Planetary Astrophysics (astro-ph.EP), Physics, stars: individual: epsilon Indi Ba and Bb, Brown dwarfs, Settore FIS/05, photometric [Techniques], TIME-SERIES OBSERVATIONS, individual: epsilon Indi Ba and Bb [stars], DAS, Astronomy and Astrophysics, Bb, Lightning, VARIABILITY, individual: ɛ Indi Ba and Bb [Stars], QC Physics, brown dwarfs, Space and Planetary Science, astro-ph.EP, H-alpha, QB799
Abstract

Funding: LM acknowledges support from the University of Rome Tor Vergata through ‘Mission: Sustainability 2017’ fund. ChH and GH gratefully acknowledge the support of the European Research Council (ERC) Starting Grant no. 257431. We present the results of 14 nights of I-band photometric monitoring ofthe nearby brown dwarf binary, ɛ Indi Ba,Bb. Observations were acquired over 2 months, and total close to 42 hours of coverage at a typically high cadence of 1.4 minutes. At a separation of just 0.7″, we do not resolve the individual components, and so effectively treat the binary as if it were a single object. However, ɛ Indi Ba (spectral type T1) is the brightest known T-type brown dwarf, and is expected to dominate the photometric signal. We typically find no strong variability associated with the target during each individual night of observing, but see significant changes in mean brightness - by as much as 0.10 magnitudes - over the 2 months of the campaign. This strong variation is apparent on a timescale of at least 2 days. We detect no clear periodic signature, which suggests we may be observing the T1 brown dwarf almost pole-on, and the days-long variability in mean brightness is caused by changes in the large-scale structure of the cloud coverage. Dynamic clouds will very likely produce lightning, and complementary high cadence V-band and Hα images were acquired to search for the emission signatures associated with stochastic 'strikes'. We report no positive detections for the target in either of these passbands. Publisher PDF

Published
2020

23. Six Outbursts of Comet 46P/Wirtanen

Author

Richard Walters, M. Hundertmark, Sedighe Sajadian, Andrew Drake, Eduardo Unda-Sanzana, Thomas Kupfer, Johannes Allen, Dennis Bodewits, Penélope Longa-Peña, Sohrab Rahvar, Eric C. Bellm, Daniel J. Reiley, J. Tregloan-Reed, Frank J. Masci, Tony L. Farnham, John Southworth, Jesper Skottfelt, Jian-Yang Li, U. G. Jørgensen, E. Khalouei, M. Rabus, A. E. Andrews, Tobias C. Hinse, Colin Snodgrass, Martin Dominik, Dmitry A. Duev, Valerio Bozza, N. Bach-Møller, Michael W. Coughlin, J. Campbell-White, Yuka Fujii, Martin Burgdorf, Matthew J. Graham, Sami Dib, Michael S. P. Kelley, European Commission, University of St Andrews. School of Physics and Astronomy, and University of St Andrews. St Andrews Centre for Exoplanet Science

Subjects
Engineering, Solar System, Astrophysics::High Energy Astrophysical Phenomena, Comet, FOS: Physical sciences, Coma dust (2159), 01 natural sciences, Spitzer Space Telescope, 0103 physical sciences, Earth and Planetary Sciences (miscellaneous), Comets, media_common.cataloged_instance, Astrophysics::Solar and Stellar Astrophysics, QB Astronomy, European union, 010303 astronomy & astrophysics, QC, media_common, Short period comets (1452), QB, Earth and Planetary Astrophysics (astro-ph.EP), MCC, Broad band photometry (184), 010308 nuclear & particles physics, business.industry, Broad band photometry, Foundation (engineering), Astronomy, Astronomy and Astrophysics, Comets (280), 3rd-DAS, Geophysics, QC Physics, 13. Climate action, Space and Planetary Science, Physics::Space Physics, astro-ph.EP, Coma dust, Astrophysics::Earth and Planetary Astrophysics, business, Short period comets, Astrophysics - Earth and Planetary Astrophysics
Abstract

Cometary activity is a manifestation of sublimation-driven processes at the surface of nuclei. However, cometary outbursts may arise from other processes that are not necessarily driven by volatiles. In order to fully understand nuclear surfaces and their evolution, we must identify the causes of cometary outbursts. In that context, we present a study of mini-outbursts of comet 46P/Wirtanen. Six events are found in our long-term lightcurve of the comet around its perihelion passage in 2018. The apparent strengths range from $-0.2$ to $-1.6$ mag in a 5" radius aperture, and correspond to dust masses between $\sim10^4$ to $10^6$ kg, but with large uncertainties due to the unknown grain size distributions. However, the nominal mass estimates are the same order of magnitude as the mini-outbursts at comet 9P/Tempel 1 and 67P/Churyumov-Gerasimenko, events which were notably lacking at comet 103P/Hartley 2. We compare the frequency of outbursts at the four comets, and suggest that the surface of 46P has large-scale ($\sim$10-100 m) roughness that is intermediate to that of 67P and 103P, if not similar to the latter. The strength of the outbursts appear to be correlated with time since the last event, but a physical interpretation with respect to solar insolation is lacking. We also examine Hubble Space Telescope images taken about 2 days following a near-perihelion outburst. No evidence for macroscopic ejecta was found in the image, with a limiting radius of about 2-m., Comment: Accepted for publication in The Planetary Science Journal. 33 pages, 11 figures, 3 tables

Published
2021

24. Decoding a black hole metric from the interferometric pattern of the relativistic images of a compact source

Author

Fabio Aratore and Valerio Bozza

Subjects
Physics, High Energy Astrophysical Phenomena (astro-ph.HE), Photon, General relativity, Astrophysics::High Energy Astrophysical Phenomena, Visibility (geometry), FOS: Physical sciences, Astronomy and Astrophysics, GR black holes, Observer (special relativity), General Relativity and Quantum Cosmology (gr-qc), General Relativity and Quantum Cosmology, Computational physics, gravity, Black hole, Gravitational lens, accretion, Metric (mathematics), Shadow, massive black holes, Astrophysics - High Energy Astrophysical Phenomena
Abstract

Photons emitted by light sources in the neighbourhood of a black hole can wind several times around it before fleeing towards the observer. For spherically symmetric black holes, two infinite sequences of images are created for any given source, asymptotically approaching the shadow border with decreasing magnitude. These sequences are reflected by a characteristic staircase structure in the complex visibility function that may be used to decode the properties of the black hole metric. Recalling the formalism of gravitational lensing in the strong deflection limit, we derive analytical formulae for the height, the width and the periodicities of the steps in the visibility as functions of the black hole parameters for the case of a single compact and distant source. With respect to diffuse emission by the whole accretion flow, this ideal framework provides clean insight and model-independent information on the metric. These basic formulae can then be used to build visibilities for more complicated sources and track the changes induced by alternative metrics and ultimately test General Relativity. As simple examples, we include visibilities for Reissner-Nordstr\"om and Janis-Newman-Winicour metrics., Comment: 20 pages, 8 figures

Published
2021

25. MOA-2006-BLG-074: recognizing xallarap contaminants in planetary microlensing

Author

Akihiko Fukui, Rintaro Kirikawa, Greg Olmschenk, Clément Ranc, Yuki Hirao, Daisuke Suzuki, Aparna Bhattacharya, Yutaka Matsubara, Ian A. Bond, Martin Donachie, Yoshitaka Itow, Yuki Satoh, Shota Miyazaki, Takahiro Sumi, P. Rota, Naoki Koshimoto, S. Ishitani Silva, D. P. Bennett, Yasushi Muraki, Paul J. Tristram, Atsunori Yonehara, Man Cheung Alex Li, Richard K. Barry, Valerio Bozza, Fumio Abe, and Hirosane Fujii

Subjects
Binary number, FOS: Physical sciences, Astrophysics, Gravitational microlensing, Binary stars, 01 natural sciences, Gravitational microlensing exoplanet detection, Planet, 0103 physical sciences, Binary star, 010303 astronomy & astrophysics, Instrumentation and Methods for Astrophysics (astro-ph.IM), Physics, Earth and Planetary Astrophysics (astro-ph.EP), 010308 nuclear & particles physics, Xallarap effect, Xallarap, Astronomy and Astrophysics, Light curve, Astrophysics - Astrophysics of Galaxies, Binary source microlensing, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), Orbital motion, Caustic (optics), Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - Earth and Planetary Astrophysics
Abstract

MOA-2006-BLG-074 was selected as one of the most promising planetary candidates in a retrospective analysis of the MOA collaboration: its asymmetric high-magnification peak can be perfectly explained by a source passing across a central caustic deformed by a small planet. However, after a detailed analysis of the residuals, we have realized that a single lens and a source orbiting with a faint companion provides a more satisfactory explanation for all the observed deviations from a Paczynski curve and the only physically acceptable interpretation. Indeed the orbital motion of the source is constrained enough to allow a very good characterization of the binary source from the microlensing light curve. The case of MOA-2006-BLG-074 suggests that the so-called xallarap effect must be taken seriously in any attempts to obtain accurate planetary demographics from microlensing surveys., 14 pages, 8 figures, accepted by AAS

Published
2021

26. OGLE-2018-BLG-1185b : A Low-Mass Microlensing Planet Orbiting a Low-Mass Dwarf

Author

Man Cheung Alex Li, Yuri I. Fujii, H.-W. Kim, Michael D. Albrow, Valerio Bozza, Igor Soszyński, Hirosane Fujii, Patryk Iwanek, John Southworth, Yossi Shvartzvald, S. Kozlowski, Hikaru Shoji, Iona Kondo, Yuki Hirao, S. Ishitani Silva, M. T. Penny, Sean Carey, J. Campbell-White, Nicholas J. Rattenbury, Jan Skowron, D. Maoz, Joachim Wambsganss, Penélope Longa-Peña, G. Bryden, D.-J. Kim, Yuki Satoh, Takahiro Sumi, S. Calchi Novati, S. J. Chung, David P. Bennett, Akihiko Fukui, Shude Mao, Sohrab Rahvar, Shinyoung Kim, U. G. Jørgensen, Yiannis Tsapras, B. S. Gaudi, Yasushi Muraki, Yongseok Lee, Atsunori Yonehara, Fumio Abe, Andrzej Udalski, Ian A. Bond, Keith Horne, Daisuke Suzuki, J. Tregloan-Reed, Arnaud Cassan, Jesper Skottfelt, Yoshitaka Itow, Paul J. Tristram, Colin Snodgrass, Michał K. Szymański, Nuno Peixinho, R. W. Pogge, Shota Miyazaki, Wei Zhu, M. Wrona, C.-U. Lee, Greg Olmschenk, Duk-Hang Lee, Sang-Mok Cha, Byeong-Gon Park, E. Khalouei, Kyu-Ha Hwang, Youn Kil Jung, P. Pietrukowicz, Radosław Poleski, Naoki Koshimoto, P. Mróz, C. A. Beichman, Yoshimi Matsubara, Andrew Gould, Clément Ranc, Martin Dominik, R. A. Street, Weicheng Zang, Rintaro Kirikawa, Yuzuru Tanaka, Martin Donachie, C. Han, Richard K. Barry, Tobias C. Hinse, Krzysztof Ulaczyk, M. Hundertmark, Abhijit Saha, Sami Dib, Aparna Bhattacharya, Martin Burgdorf, Krzysztof A. Rybicki, Tsubasa Yamawaki, Yoon-Hyun Ryu, Calen B. Henderson, Sedighe Sajadian, Jennifer C. Yee, Etienne Bachelet, M. Rabus, D. M. Bramich, In-Gu Shin, European Commission, University of St Andrews. School of Physics and Astronomy, and University of St Andrews. St Andrews Centre for Exoplanet Science

Subjects
010504 meteorology & atmospheric sciences, Star (game theory), FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Gravitational microlensing, Q1, 01 natural sciences, Gravitational microlensing exoplanet detection, Spitzer Space Telescope, 0103 physical sciences, QB460, QB Astronomy, Astrophysics::Solar and Stellar Astrophysics, Satellite microlensing parallax, 010303 astronomy & astrophysics, QB600, QC, Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences, QB, Physics, Earth and Planetary Astrophysics (astro-ph.EP), Astronomy and Astrophysics, 3rd-DAS, Planetary system, Mass ratio, Light curve, Exoplanet, QC Physics, 13. Climate action, Space and Planetary Science, Astrophysics::Earth and Planetary Astrophysics, Low Mass, Astrophysics - Earth and Planetary Astrophysics
Abstract

We report the analysis of planetary microlensing event OGLE-2018-BLG-1185, which was observed by a large number of ground-based telescopes and by the $Spitzer$ Space Telescope. The ground-based light curve indicates a low planet-host star mass ratio of $q = (6.9 \pm 0.2) \times 10^{-5}$, which is near the peak of the wide-orbit exoplanet mass-ratio distribution. We estimate the host star and planet masses with a Bayesian analysis using the measured angular Einstein radius under the assumption that stars of all masses have an equal probability to host this planet. The flux variation observed by $Spitzer$ was marginal, but still places a constraint on the microlens parallax. Imposing a conservative constraint that this flux variation should be $\Delta f_{\rm Spz} < 4$ instrumental flux units indicates a host mass of $M_{\rm host} = 0.37^{+0.35}_{-0.21}\ M_\odot$ and a planet mass of $m_{\rm p} = 8.4^{+7.9}_{-4.7}\ M_\oplus$. A Bayesian analysis including the full parallax constraint from $Spitzer$ suggests smaller host star and planet masses of $M_{\rm host} = 0.091^{+0.064}_{-0.018}\ M_\odot$ and $m_{\rm p} = 2.1^{+1.5}_{-0.4}\ M_\oplus$, respectively. Future high-resolution imaging observations with $HST$ or ELTs could distinguish between these two scenarios and help to reveal the planetary system properties in more detail., Comment: 30 pages, 11 figures, 5 tables, Accepted for publication in Astronomical Journal (AJ)

Published
2021

27. Three faint-source microlensing planets detected via resonant-caustic channel

Author

Radosław Poleski, Dong-Joo Lee, Valerio Bozza, Michael D. Albrow, Chung-Uk Lee, Andrzej Udalski, Michał K. Szymański, Dong-Jin Kim, Sun-Ju Chung, Cheongho Han, Paweł Pietrukowicz, Sang-Mok Cha, Richard W. Pogge, Szymon Kozłowski, Andrew Gould, Yongseok Lee, Weicheng Zang, Krzysztof Ulaczyk, Mariusz Gromadzki, Seung-Lee Kim, Yossi Shvartzvald, Igor Soszyński, Youn Kil Jung, Patryk Iwanek, Jan Skowron, In-Gu Shin, Byeong-Gon Park, Krzysztof A. Rybicki, Hyoun-Woo Kim, Kyu-Ha Hwang, M. Wrona, Doeon Kim, Przemek Mróz, Jennifer C. Yee, and Yoon-Hyun Ryu

Subjects
Solar System, Einstein ring, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Gravitational microlensing, Gravitational lensing: micro, Jupiter, symbols.namesake, Planet, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Galaxy Astrophysics, Physics, Earth and Planetary Astrophysics (astro-ph.EP), Planets and satellites: detection, Astronomy and Astrophysics, Planetary system, Light curve, Astrophysics - Astrophysics of Galaxies, Stars, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), symbols, Astrophysics::Earth and Planetary Astrophysics, Astrophysics - Earth and Planetary Astrophysics
Abstract

We conducted a project of reinvestigating the 2017--2019 microlensing data collected by the high-cadence surveys with the aim of finding planets that were missed due to the deviations of planetary signals from the typical form of short-term anomalies. The project led us to find three planets including KMT-2017-BLG-2509Lb, OGLE-2017-BLG-1099Lb, and OGLE-2019-BLG-0299Lb. The lensing light curves of the events have a common characteristic that the planetary signals were produced by the crossings of faint source stars over the resonant caustics formed by giant planets located near the Einstein rings of host stars. For all planetary events, the lensing solutions are uniquely determined without any degeneracy. It is estimated that the host masses are in the range of $0.45\lesssim M/M_\odot \lesssim 0.59$, which corresponds to early M to late K dwarfs, and thus the host stars are less massive than the sun. On the other hand, the planets, with masses in the range of $2.1\lesssim M/M_{\rm J}\lesssim 6.2$, are heavier than the heaviest planet of the solar system, that is, Jupiter. The planets in all systems lie beyond the snow lines of the hosts, and thus the discovered planetary systems, together with many other microlensing planetary systems, support that massive gas-giant planets are commonplace around low-mass stars. We discuss the role of late-time high-resolution imaging in clarifying resonant-image lenses with very faint sources., Comment: 10 pages, 13 figures, 6 tables

Published
2021
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28. A public code for astrometric microlensing with contour integration

Author

E. Khalouei, Valerio Bozza, and Etienne Bachelet

Subjects
FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Gravitational microlensing, Astrometry, Binaries: general, Gravitational lensing: micro, Planets and satellites: detection, Software: development, 01 natural sciences, Space exploration, 0103 physical sciences, 010303 astronomy & astrophysics, Instrumentation and Methods for Astrophysics (astro-ph.IM), Astrophysics::Galaxy Astrophysics, Physics, Earth and Planetary Astrophysics (astro-ph.EP), 010308 nuclear & particles physics, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy and Astrophysics, Methods of contour integration, Astrophysics - Astrophysics of Galaxies, Space and Planetary Science, Limb darkening, Astrophysics of Galaxies (astro-ph.GA), Astrophysics::Earth and Planetary Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics, Algorithm, Astrophysics - Earth and Planetary Astrophysics
Abstract

We present the first public code for the calculation of the astrometric centroid shift occurring during microlensing events. The computation is based on the contour integration scheme and covers single and binary lensing of finite sources with arbitrary limb darkening profiles. This allows for general detailed investigations of the impact of finite source size in astrometric binary microlensing. The new code is embedded in version 3.0 of VBBinaryLensing, which offers a powerful computational tool for extensive studies of microlensing data from current surveys and future space missions., 10 pages, 6 figures, accepted by MNRAS

Published
2020

29. OGLE-2013-BLG-0911Lb: A Secondary on the Brown-dwarf Planet Boundary around an M Dwarf

Author

Hiroshi Shibai, Valerio Bozza, Markus Rabus, N. Kains, R. W. Pogge, Shota Miyazaki, Y. Kamei, Giuseppe D'Ago, Darren L. DePoy, David P. Bennett, Man Cheung Alex Li, Michael D. Albrow, Masayuki Nagakane, P. Verma, Yoshitaka Itow, Shude Mao, Ian A. Bond, K. Ohnishi, S. KozŁowski, Daniel F. Evans, S. Calchi Novati, Dan Maoz, M. Friedmann, C. H. Ling, Jennifer C. Yee, P. Mróz, Nicholas J. Rattenbury, Haruno Suematsu, Jan Skowron, M. Hundertmark, To. Saito, Shai Kaspi, John Southworth, I. Porritt, Eamonn Kerins, Etienne Bachelet, Daisuke Suzuki, Akihiko Fukui, Ilan Manulis, Wise Team, Arnaud Cassan, Jesper Skottfelt, Yuki Hirao, Colin Snodgrass, Yutaka Matsubara, Andrzej Udalski, Tobias C. Hinse, Michał K. Szymański, C.-U. Lee, H. Ngan, Avishay Gal-Yam, Nuno Peixinho, Krzysztof Ulaczyk, R. W. Schmidt, Fumio Abe, Yossi Shvartzvald, Martin Donachie, Denis J. Sullivan, R. Figuera Jaimes, Gaetano Scarpetta, Hirosane Fujii, Luigi Mancini, Iain A. Steele, Andrew Gould, Clément Ranc, Tim Natusch, J. W. Menzies, A. Sharan, Iona Kondo, Taro Matsuo, Rachel Street, Yasushi Muraki, Atsunori Yonehara, T. Yamakawa, Keith Horne, Takahiro Sumi, Simona Ciceri, Jennie McCormick, G. W. Christie, Joachim Wambsganss, U. G. Jørgensen, Yiannis Tsapras, A. Popovas, P. Pietrukowicz, Radosław Poleski, Naoki Koshimoto, Łukasz Wyrzykowski, Martin Dominik, D. M. Bramich, Igor Soszyński, Heidi Korhonen, Richard K. Barry, Aparna Bhattacharya, RoboNet Collabofratino, Martin Burgdorf, Sohrab Rahvar, Paul J. Tristram, Science & Technology Facilities Council, University of St Andrews. School of Physics and Astronomy, and University of St Andrews. St Andrews Centre for Exoplanet Science

Subjects
astro-ph.SR, Extrasolar gas giants, 010504 meteorology & atmospheric sciences, Exoplanet astronomy, astro-ph.GA, Microlensing, Brown dwarf, FOS: Physical sciences, Boundary (topology), Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Gravitational microlensing, M dwarf stars, 01 natural sciences, Einstein radius, Planet, 0103 physical sciences, Exoplanet detection methods, QB Astronomy, Astrophysics::Solar and Stellar Astrophysics, Exoplanet systems, 010303 astronomy & astrophysics, QC, Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics::Galaxy Astrophysics, QB, 0105 earth and related environmental sciences, Earth and Planetary Astrophysics (astro-ph.EP), Physics, Brown dwarfs, Settore FIS/05, Exoplanets, Order (ring theory), Astronomy and Astrophysics, 3rd-DAS, Mass ratio, Astrophysics - Astrophysics of Galaxies, QC Physics, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), astro-ph.EP, High Energy Physics::Experiment, Astrophysics::Earth and Planetary Astrophysics, Astrophysics - Earth and Planetary Astrophysics
Abstract

We present the analysis of the binary-lens microlensing event OGLE-2013-BLG-0911. The best-fit solutions indicate the binary mass ratio of q~0.03 which differs from that reported in Shvartzvald+2016. The event suffers from the well-known close/wide degeneracy, resulting in two groups of solutions for the projected separation normalized by the Einstein radius of s~0.15 or s~7. The finite source and the parallax observations allow us to measure the lens physical parameters. The lens system is an M-dwarf orbited by a massive Jupiter companion at very close (M_{host}=0.30^{+0.08}_{-0.06} M_{Sun}, M_{comp}=10.1^{+2.9}_{-2.2} M_{Jup}, a_{exp}=0.40^{+0.05}_{-0.04} au) or wide (M_{host}=0.28^{+0.10}_{-0.08} M_{Sun}, M_{comp}=9.9^{+3.8}_{-3.5}M_{Jup}, a_{exp}=18.0^{+3.2}_{-3.2} au) separation. Although the mass ratio is slightly above the planet-brown dwarf (BD) mass-ratio boundary of q=0.03 which is generally used, the median physical mass of the companion is slightly below the planet-BD mass boundary of 13M_{Jup}. It is likely that the formation mechanisms for BDs and planets are different and the objects near the boundaries could have been formed by either mechanism. It is important to probe the distribution of such companions with masses of ~13M_{Jup} in order to statistically constrain the formation theories for both BDs and massive planets. In particular, the microlensing method is able to probe the distribution around low-mass M-dwarfs and even BDs which is challenging for other exoplanet detection methods., Comment: 22 pages, 10 figures, Accepted for publication in The Astronomical Journal

Published
2020

30. Candidate Brown-dwarf Microlensing Events with Very Short Timescales and Small Angular Einstein Radii

Author

David P. Bennett, Yoshitaka Itow, Yoon-Hyun Ryu, Kyu-Ha Hwang, D. J. Sullivan, Ian A. Bond, Cheongho Han, Tsubasa Yamawaki, Szymon Kozłowski, Valerio Bozza, Igor Soszyński, Yuki Hirao, T. Yamakawa, Haruno Suematsu, Marcin Wrona, Yossi Shvartzvald, Yongseok Lee, Byeong-Gon Park, In-Gu Shin, Yuhei Kamei, Hikaru Shoji, Jennifer C. Yee, Krzysztof Ulaczyk, Chung-Uk Lee, Paul J. Tristram, Hirosane Fujii, Andrzej Udalski, Michał K. Szymański, Andrew Gould, Patryk Iwanek, Daisuke Suzuki, M. James Jee, Nicholas J. Rattenbury, Jan Skowron, Masayuki Nagakane, Michael D. Albrow, Sun-Ju Chung, Akihiko Fukui, Yasushi Muraki, Doeon Kim, Hyoun-Woo Kim, Atsunori Yonehara, Radek Poleski, Przemek Mróz, Shota Miyazaki, Fumio Abe, Clément Ranc, Weicheng Zang, Man Cheung Alex Li, Yuki Satoh, Takahiro Sumi, Seung-Lee Kim, Sang-Mok Cha, Dong-Jin Kim, Richard Barry, Richard W. Pogge, Yutaka Matsubara, Martin Donachie, Dong-Joo Lee, Iona Kondo, Youn Kil Jung, Naoki Koshimoto, Aparna Bhattacharya, Krzysztof A. Rybicki, and Paweł Pietrukowicz

Subjects
010504 meteorology & atmospheric sciences, Monte Carlo method, Brown dwarf, Binary number, FOS: Physical sciences, Astrophysics, Gravitational microlensing, 01 natural sciences, law.invention, symbols.namesake, law, 0103 physical sciences, Einstein, 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), 0105 earth and related environmental sciences, Event (probability theory), Physics, Earth and Planetary Astrophysics (astro-ph.EP), Brown dwarfs, Astronomy and Astrophysics, Lens (optics), Stars, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, symbols, Astrophysics - Earth and Planetary Astrophysics
Abstract

Short-timescale microlensing events are likely to be produced by substellar brown dwarfs (BDs), but it is difficult to securely identify BD lenses based on only event timescales $t_{\rm E}$ because short-timescale events can also be produced by stellar lenses with high relative lens-source proper motions. In this paper, we report three strong candidate BD-lens events found from the search for lensing events not only with short timescales ($t_{\rm E} \lesssim 6~{\rm days}$) but also with very small angular Einstein radii ($\theta_{\rm E}\lesssim 0.05~{\rm mas}$) among the events that have been found in the 2016--2019 observing seasons. These events include MOA-2017-BLG-147, MOA-2017-BLG-241, and MOA-2019-BLG-256, in which the first two events are produced by single lenses and the last event is produced by a binary lens. From the Bayesian analysis conducted with the combined $t_{\rm E}$ and $\theta_{\rm E}$ constraint, it is estimated that the lens masses of the individual events are $0.051^{+0.100}_{-0.027}~M_\odot$, $0.044^{+0.090}_{-0.023}~M_\odot$, and $0.046^{+0.067}_{-0.023}~M_\odot/0.038^{+0.056}_{-0.019}~M_\odot$ and the probability of the lens mass smaller than the lower limit of stars is $\sim 80\%$ for all events. We point out that routine lens mass measurements of short time-scale lensing events require survey-mode space-based observations., Comment: 9 pages, 6 figures

Published
2020

31. Transit timing variations in the WASP-4 planetary system

Author

E. Khalouei, M. Hundertmark, Samuel Gill, U. G. Jørgensen, Sami Dib, Valerio Bozza, Penélope Longa-Peña, C. von Essen, Sedighe Sajadian, Michael I. Andersen, Tobias C. Hinse, Lauri K. Haikala, R. Figuera Jaimes, Luigi Mancini, John Southworth, Colin Snodgrass, Eduardo Unda-Sanzana, Giuseppe D'Ago, J. Tregloan-Reed, Heidi Korhonen, Jesper Skottfelt, M. Rabus, Sohrab Rahvar, P. Spyratos, Martin Burgdorf, Nuno Peixinho, Martin Dominik, Yuri I. Fujii, University of Copenhagen = Københavns Universitet (KU), FORMATION STELLAIRE 2019, Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Department of Physics [Helsinki], Falculty of Science [Helsinki], University of Helsinki-University of Helsinki, Kuopio Unit [FMI], Finnish Meteorological Institute (FMI), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Instituto de Astrofisica de Canarias (IAC), Department of Physics [Tehran], Sharif University of Technology [Tehran] (SUT), Max-Planck-Institut für Sonnensystemforschung (MPS), Max-Planck-Gesellschaft, Instituto de Astronomıa, universidad catolica del Norte, University of St Andrews. School of Physics and Astronomy, and University of St Andrews. St Andrews Centre for Exoplanet Science

Subjects
fundamental parameters [stars], FOS: Physical sciences, Orbital decay, Ephemeris, 01 natural sciences, 0103 physical sciences, Hot Jupiter, stars: activity, QB Astronomy, Transit (astronomy), 010303 astronomy & astrophysics, Stars: activity, Stars: fundamental parameters, Stars: individual: WASP-4, QC, QB, Physics, Earth and Planetary Astrophysics (astro-ph.EP), stars: activity, stars: fundamental parameters, stars: individual: WASP-4, activity [stars], 010308 nuclear & particles physics, Settore FIS/05, Apsidal precession, stars: individual: WASP-4, individual: WASP-4 [stars], Astronomy, Astronomy and Astrophysics, 3rd-DAS, Planetary system, fundemental parameters [Stars], Exoplanet, Planetary systems, QC Physics, 13. Climate action, Space and Planetary Science, astro-ph.EP, Satellite, stars: fundamental parameters, [SDU.ASTR.GA]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Galactic Astrophysics [astro-ph.GA], Astrophysics::Earth and Planetary Astrophysics, Astrophysics - Earth and Planetary Astrophysics, QB799
Abstract

Transits in the planetary system WASP-4 were recently found to occur 80s earlier than expected in observations from the TESS satellite. We present 22 new times of mid-transit that confirm the existence of transit timing variations, and are well fitted by a quadratic ephemeris with period decay dP/dt = -9.2 +/- 1.1 ms/yr. We rule out instrumental issues, stellar activity and the Applegate mechanism as possible causes. The light-time effect is also not favoured due to the non-detection of changes in the systemic velocity. Orbital decay and apsidal precession are plausible but unproven. WASP-4b is only the third hot Jupiter known to show transit timing variations to high confidence. We discuss a variety of observations of this and other planetary systems that would be useful in improving our understanding of WASP-4 in particular and orbital decay in general., Comment: Accepted for publication to MNRAS Main Journal. 7 pages, 2 colour figures, 1 table. Version 2 is the revised version after the refereeing process, which includes changes to some of the conclusions of the paper

Published
2019

32. Demographics of Exoplanetary Systems : Lecture Notes of the 3rd Advanced School on Exoplanetary Science

Author

Katia Biazzo, Valerio Bozza, Luigi Mancini, Alessandro Sozzetti, Katia Biazzo, Valerio Bozza, Luigi Mancini, and Alessandro Sozzetti

Subjects
Extrasolar planets--Congresses
Abstract

This book provides a detailed, state-of-the-art overview of key observational and theoretical aspects of the rapidly developing and highly interdisciplinary field of exoplanet science, as viewed through the lenses of eight world-class experts. It equips readers with a broad understanding of the complex processes driving the formation and the physical and dynamical evolution of planetary systems. It juxtaposes theoretical modeling with the host of techniques that are unveiling the exceptional variety of observed properties of close-in and wide-separation extrasolar planets. By effectively linking ingenious interpretative analyses to the main factors shaping planetary populations, the book ultimately provides the most coherent picture to date of the demographics of exoplanetary systems. It is an essential reference for Ph.D. students and early-stage career researchers, while the scope and depth of its source material also provide excellent cues for graduate-level courses.

Published
2022

33. Erratum: Large-scale changes of the cloud coverage in the ϵ Indi Ba and Bb system

Author

John Southworth, Martin Dominik, Lauri K. Haikala, M. Hundertmark, Jesper Skottfelt, Alexander Scholz, U. G. Jørgensen, M. Rabus, Valerio Bozza, Yuri I. Fujii, G. Hodosán, Th. Henning, Christiane Helling, C. von Essen, Sedighe Sajadian, L. Mancini, Penélope Longa-Peña, J. Campbell-White, Colin Snodgrass, Stephen C. Lowry, Sohrab Rahvar, Roberto Figuera Jaimes, Martin Burgdorf, Tobias C. Hinse, and James A. Hitchcock

Subjects
Physics, Scale (ratio), Space and Planetary Science, business.industry, Brown dwarf, Astronomy and Astrophysics, Cloud computing, Atmospheric sciences, business
Published
2021

34. The lowest mass ratio planetary microlens: OGLE 2016–BLG–1195Lb

Author

Igor Soszyński, Aparna Bhattacharya, Fumio Abe, David P. Bennett, Masayuki Nagakane, Yasushi Muraki, Richard K. Barry, To. Saito, Man Cheung Alex Li, Yutaka Matsubara, Michał Pawlak, Atsunori Yonehara, Phil Evans, K. Ohnishi, C. H. Ling, Yoshitaka Itow, Yuichiro Asakura, Krzysztof Ulaczyk, A. Sharan, Daisuke Suzuki, T. Yamada, Kimiaki Masuda, Ian A. Bond, P. Pietrukowicz, Radosław Poleski, Naoki Koshimoto, Clément Ranc, Martin Donachie, Denis J. Sullivan, P. Mróz, Nicholas J. Rattenbury, Jan Skowron, Andrzej Udalski, Michał K. Szymański, Yuki Hirao, Valerio Bozza, Paul J. Tristram, Akihiko Fukui, Takahiro Sumi, and S. Kozlowski

Subjects
Earth and Planetary Astrophysics (astro-ph.EP), Physics, Solar mass, FOS: Physical sciences, Astronomy, Astronomy and Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Mass ratio, Earth mass, Light curve, Gravitational microlensing, 01 natural sciences, Exoplanet, Space and Planetary Science, Planet, 0103 physical sciences, Astrophysics::Earth and Planetary Astrophysics, 010306 general physics, 010303 astronomy & astrophysics, Planetary mass, Astrophysics::Galaxy Astrophysics, Astrophysics - Earth and Planetary Astrophysics
Abstract

We report discovery of the lowest mass ratio exoplanet to be found by the microlensing method in the light curve of the event OGLE~2016--BLG--1195. This planet revealed itself as a small deviation from a microlensing single lens profile from an examination of the survey data soon after the planetary signal. The duration of the planetary signal is $\sim 2.5\,$hours. The measured ratio of the planet mass to its host star is $q = 4.2\pm 0.7 \times10^{-5}$. We further estimate that the lens system is likely to comprise a cold $\sim$3 Earth mass planet in a $\sim\,$2 AU wide orbit around a 0.2 Solar mass star at an overall distance of 7.1 kpc., 8 pages, 5 figures, accepted for publication in MNRAS

Published
2017

35. ROME/REA: A gravitational microlensing search for exo-planets beyond the snow-line on a global network of robotic telescopes

Author

Joachim Wambsganss, Yiannis Tsapras, M. Hundertmark, Etienne Bachelet, D. M. Bramich, Weichen Zang, Arnaud Cassan, Martin Dominik, Rachel Street, Abhijit Saha, Keith Horne, Valerio Bozza, Shude Mao, Science & Technology Facilities Council, University of St Andrews. School of Physics and Astronomy, and University of St Andrews. St Andrews Centre for Exoplanet Science

Subjects
010504 meteorology & atmospheric sciences, bulge [Galaxy], FOS: Physical sciences, Gravitational microlensing, 01 natural sciences, micro [Gravitational lensing], 0103 physical sciences, Global network, Snow line, QB Astronomy, observational [Methods], data analysis [Methods], Instrumentation and Methods for Astrophysics (astro-ph.IM), 010303 astronomy & astrophysics, QC, QB, 0105 earth and related environmental sciences, Earth and Planetary Astrophysics (astro-ph.EP), Physics, Astronomy, DAS, Astronomy and Astrophysics, Planetary system, Methods observational, Exoplanet, Planetary systems, QC Physics, 13. Climate action, Space and Planetary Science, Astrophysics::Earth and Planetary Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - Earth and Planetary Astrophysics
Abstract

Planet population synthesis models predict an abundance of planets with semi-major axes between 1-10 au, yet they lie at the edge of the detection limits of most planet finding techniques. Discovering these planets and studying their distribution is critical to understanding the physical processes that drive planet formation. ROME/REA is a gravitational microlensing project whose main science driver is to discover exoplanets in the cold outer regions of planetary systems. To achieve this, it uses a novel approach combining a multi-band survey with reactive follow-up observations, exploiting the unique capabilities of the Las Cumbres Observatory (LCO) global network of robotic telescopes combined with a Target and Observation Manager (TOM) system. We present the main science objectives and a technical overview of the project, including initial results., 15 pages, 6 figures, published (Publications of the Astronomical Society of the Pacific, 131:124401 (12pp), 2019 December)

Published
2019

36. OGLE-2018-BLG-1011Lb,c: Microlensing Planetary System with Two Giant Planets Orbiting a Low-mass Star

Author

B. Scott Gaudi, Masayuki Nagakane, Andrzej Udalski, Man Cheung Alex Li, Michał K. Szymański, Radek Poleski, Charles Beichman, Jennifer C. Yee, Sun-Ju Chung, Kohei Kawasaki, Igor Soszyński, Matthew T. Penny, Paweł Pietrukowicz, Dong-Jin Kim, M. Hundertmark, Keivan G. Stassun, Etienne Bachelet, Chung-Uk Lee, Byeong-Gon Park, In-Gu Shin, Cheongho Han, Marcin Wrona, Richard Barry, Sebastiano Calchi Novati, Youn Kil Jung, Fumio Abe, Andrew Gould, Clément Ranc, Yasushi Muraki, Weicheng Zang, Yongseok Lee, Atsunori Yonehara, D. J. Lee, K. H. Hwang, Richard W. Pogge, Aparna Bhattacharya, Paul J. Tristram, Daisuke Suzuki, Yutaka Matsubara, Seung-Lee Kim, Michael D. Albrow, Haruno Suematsu, Arnaud Cassan, Yoon-Hyun Ryu, Kay-Sebastian Nikolaus, David P. Bennett, Hyoun-Woo Kim, K. A. Rybicki, Szymon Kozłowski, Krzysztof Ulaczyk, Pascal Fouqué, Valerio Bozza, Sang-Mok Cha, Kyeongsoo Hong, Yoshitaka Itow, Wei Zhu, Geoffery Bryden, Martin Donachie, Tianshu Wang, Shota Miyazaki, Denis J. Sullivan, Naoki Koshimoto, Calen B. Henderson, Savannah Jacklin, Shude Mao, Patryk Iwanek, Przemek Mróz, Nicholas J. Rattenbury, Jan Skowron, Ian A. Bond, Iona Kondo, Akihiko Fukui, Doeon Kim, Takahiro Sumi, Yuki Hirao, and Yossi Shvartzvald

Subjects
gravitational lensing: micro, planetary systems, Physics, Earth and Planetary Astrophysics (astro-ph.EP), 010504 meteorology & atmospheric sciences, Lens (geology), Binary number, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Planetary system, Gravitational microlensing, Light curve, 01 natural sciences, Space and Planetary Science, Planet, 0103 physical sciences, Anomaly (physics), Low Mass, 010303 astronomy & astrophysics, Astrophysics - Earth and Planetary Astrophysics, 0105 earth and related environmental sciences
Abstract

著者人数: Leading authors 13名, The KMTNet Collaboration 18名, The OGLE Collaboration 11名, The MOA Collaboration 22名, The CFHT Collaboration 5名, The UKIRT Microlensing Team 7名, 全66名 (所属. 宇宙航空研究開発機構宇宙科学研究所(JAXA)(ISAS): 鈴木, 大介), Number of authors: Leading authors 13, The KMTNet Collaboration 18, The OGLE Collaboration 11, The MOA Collaboration 22, The CFHT Collaboration 5, The UKIRT Microlensing Team 7, Total 66 (Affiliation. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency(JAXA)(ISAS): Suzuki, Daisuke), Accepted: 2019-07-02, 資料番号: SA1190106000

Published
2019

37. OGLE-2015-BLG-1649Lb: A gas giant planet around a low-mass dwarf

Author

M. Hundertmark, Man Cheung Alex Li, Nicholas J. Rattenbury, Jan Skowron, R. W. Schmidt, Igor Soszyński, Daisuke Suzuki, Yasushi Muraki, Y. Kamei, Atsunori Yonehara, Arnaud Cassan, Jean-Philippe Beaulieu, Jesper Skottfelt, Keith Horne, S. Kozlowski, Heidi Korhonen, Ian A. Bond, D. M. Bramich, Akihiko Fukui, Clément Ranc, John Southworth, Michael I. Andersen, Masayuki Nagakane, Martin Donachie, Denis J. Sullivan, Etienne Bachelet, Joachim Wambsganss, Richard K. Barry, Hirosane Fujii, Iain A. Steele, Nuno Peixinho, Andrzej Udalski, Michał K. Szymański, J. W. Menzies, Aparna Bhattacharya, U. G. Jørgensen, Yiannis Tsapras, Shota Miyazaki, Martin Burgdorf, Sohrab Rahvar, Yutaka Matsubara, Tobias C. Hinse, M. Rabus, Krzysztof Ulaczyk, Paul J. Tristram, P. Mróz, Haruno Suematsu, Giuseppe D'Ago, T. Yamakawa, Chien-Hsiu Lee, Daniel F. Evans, Shude Mao, Fumio Abe, Colin Snodgrass, Valerio Bozza, P. Pietrukowicz, Radosław Poleski, Naoki Koshimoto, Martin Dominik, R. Figuera Jaimes, Yuki Hirao, Iona Kondo, Taro Matsuo, Rachel Street, Takahiro Sumi, David P. Bennett, Yoshitaka Itow, Hiroshi Shibai, P. Longa, Osaka University [Osaka], Astronomical Observatory [Warsaw], Faculty of Physics [Warsaw] (FUW), University of Warsaw (UW)-University of Warsaw (UW), Institut d'Astrophysique de Paris (IAP), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Department of Physics [Notre Dame], University of Notre Dame [Indiana] (UND), University of Auckland [Auckland], Nagoya University, Department of Physics [Osaka], Osaka University, NASA Goddard Space Flight Center (GSFC), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, Ohio State University [Columbus] (OSU), Space Science Department of ESA, European Space Research and Technology Centre (ESTEC), European Space Agency (ESA)-European Space Agency (ESA), Max-Planck-Institut für Sonnensystemforschung (MPS), Niels Bohr Institute [Copenhagen] (NBI), Faculty of Science [Copenhagen], University of Copenhagen = Københavns Universitet (KU)-University of Copenhagen = Københavns Universitet (KU), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), University of Copenhagen = Københavns Universitet (KU), Kuopio Unit [FMI], Finnish Meteorological Institute (FMI), Instituto de Astrofisica de Canarias (IAC), University of St Andrews. School of Physics and Astronomy, University of St Andrews. St Andrews Centre for Exoplanet Science, Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Agence Spatiale Européenne = European Space Agency (ESA)-Agence Spatiale Européenne = European Space Agency (ESA), Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS), University of Copenhagen = Københavns Universitet (UCPH)-University of Copenhagen = Københavns Universitet (UCPH), and University of Copenhagen = Københavns Universitet (UCPH)

Subjects
Gas giant, Exoplanet astronomy, NDAS, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Gravitational microlensing, 01 natural sciences, 0103 physical sciences, QB Astronomy, Astrophysics::Solar and Stellar Astrophysics, 010306 general physics, 010303 astronomy & astrophysics, QB600, QC, Astrophysics::Galaxy Astrophysics, QB, Earth and Planetary Astrophysics (astro-ph.EP), Physics, Exoplanet astronomy (486), Astronomy, Astronomy and Astrophysics, QC Physics, Space and Planetary Science, astro-ph.EP, Astrophysics::Earth and Planetary Astrophysics, Low Mass, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Gravitational microlensing (672), QB799, Astrophysics - Earth and Planetary Astrophysics
Abstract

著者人数: 69名 (所属. 宇宙航空研究開発機構宇宙科学研究所(JAXA)(ISAS): 鈴木, 大介), Number of authors: 69 (Affiliation. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency(JAXA)(ISAS): Suzuki, Daisuke), Accepted: 2019-09-25, 資料番号: SA1190157000

Published
2019

38. OGLE-2018-BLG-0022: First Prediction of an Astrometric Microlensing Signal from a Photometric Microlensing Event

Author

B. Scott Gaudi, K. A. Rybicki, Valerio Bozza, Andrzej Udalski, Michał K. Szymański, Yasushi Muraki, Jennifer C. Yee, Yongseok Lee, Paweł Pietrukowicz, Atsunori Yonehara, Masayuki Nagakane, Aparna Bhattacharya, Marcin Wrona, Seung-Lee Kim, David P. Bennett, Radek Poleski, Calen B. Henderson, Yoshitaka Itow, Sean Carey, K. H. Hwang, Takahiro Sumi, Andrew Gould, Woong-Tae Kim, Clément Ranc, Paul J. Tristram, Youn Kil Jung, Weicheng Zang, Kohei Kawasaki, Szymon Kozłowski, Przemek Mróz, Byeong-Gon Park, Dong-Jin Kim, Charles Beichman, D. J. Lee, Sun-Ju Chung, Ian A. Bond, Yuki Hirao, Man Cheung Alex Li, Richard W. Pogge, Cheongho Han, Yutaka Matsubara, Yossi Shvartzvald, Michael D. Albrow, Akihiko Fukui, Yoon-Hyun Ryu, Hyoun-Woo Kim, Doeon Kim, Daisuke Suzuki, Geoffery Bryden, Iona Kondo, Richard Barry, Krzysztof Ulaczyk, Arnaud Cassan, Shota Miyazaki, Naoki Koshimoto, Martin Donachie, Denis J. Sullivan, Patryk Iwanek, Nicholas J. Rattenbury, Jan Skowron, Igor Soszyński, In-Gu Shin, Chung-Uk Lee, Fumio Abe, Haruno Suematsu, and Sang-Mok Cha

Subjects
Physics, Proper motion, binaries: general, gravitational lensing: micro, 010308 nuclear & particles physics, FOS: Physical sciences, Astronomy, Centroid, Astronomy and Astrophysics, Gravitational microlensing, 01 natural sciences, Photometry (optics), Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, Bulge, 0103 physical sciences, Satellite, Parallax, 010303 astronomy & astrophysics, Event (particle physics), Solar and Stellar Astrophysics (astro-ph.SR)
Abstract

著者人数: Leading authors 7名, The KMTNet Collaboration 20名, The MOA Collaboration 23名, The OGLE Collaboration 11名, Spitzer Microlensing Team 5名, 全66名 (所属. 宇宙航空研究開発機構宇宙科学研究所(JAXA)(ISAS): 鈴木, 大介), Number of authors: Leading authors 7, The KMTNet Collaboration 20, The MOA Collaboration 23, The OGLE Collaboration 11, Spitzer Microlensing Team 5, Total 66 (Affiliation. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency(JAXA)(ISAS): Suzuki, Daisuke), Accepted: 2019-04-02, 資料番号: SA1190031000

Published
2019

39. Spitzer Microlensing Parallax for OGLE-2016-BLG-1067: A Sub-Jupiter Orbiting an M Dwarf in the Disk

Author

Charles A. Beichman, Radosław Poleski, Naoki Koshimoto, Yasushi Muraki, Yongseok Lee, Atsunori Yonehara, Clément Ranc, K. Kawasaki, David P. Bennett, Michał Pawlak, Yoshitaka Itow, Hyoun-Woo Kim, Takahiro Sumi, Richard Barry, Andrew Gould, K. H. Hwang, Paweł Pietrukowicz, Wei Zhu, Igor Soszyński, Nicholas J. Rattenbury, Jan Skowron, Sang-Mok Cha, Masayuki Nagakane, Yuki Hirao, K. Ulaczyk, W. Zang, Yossi Shvartzvald, Michael D. Albrow, Y. Asakura, Sean Carey, Spitzer Team, Ian A. Bond, Daisuke Suzuki, Geoffery Bryden, In-Gu Shin, Valerio Bozza, Paul J. Tristram, S. Miyazaki, C. H. Ling, P. Evans, Seung-Lee Kim, To. Saito, S. Calchi Novati, Chung-Uk Lee, C. Han, D. J. Lee, Dong-Jin Kim, Jennifer C. Yee, Fumio Abe, Andrzej Udalski, B. G. Park, Michał K. Szymański, Szymon Kozłowski, Man Cheung Alex Li, K. Ohnishi, S. J. Chung, Aparna Bhattacharya, Youn Kil Jung, Yoon-Hyun Ryu, Calen B. Henderson, Przemek Mróz, Martin Donachie, Denis J. Sullivan, B. S. Gaudi, Akihiko Fukui, Richard W. Pogge, Yutaka Matsubara, T. Yamada, and A. Sharan

Subjects
Earth and Planetary Astrophysics (astro-ph.EP), Physics, 010504 meteorology & atmospheric sciences, FOS: Physical sciences, Astronomy, Astronomy and Astrophysics, gravitational lensing: micro, planetary systems, Space and Planetary Science, Astrophysics::Cosmology and Extragalactic Astrophysics, Planetary system, Gravitational microlensing, 01 natural sciences, Jupiter, 0103 physical sciences, Astrophysics::Earth and Planetary Astrophysics, Parallax, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Astrophysics - Earth and Planetary Astrophysics, 0105 earth and related environmental sciences
Abstract

We report the discovery of a sub-Jupiter mass planet orbiting beyond the snow line of an M-dwarf most likely in the Galactic disk as part of the joint Spitzer and ground-based monitoring of microlensing planetary anomalies toward the Galactic bulge. The microlensing parameters are strongly constrained by the light curve modeling and in particular by the Spitzer-based measurement of the microlens parallax, $\pi_\mathrm{E}$. However, in contrast to many planetary microlensing events, there are no caustic crossings, so the angular Einstein radius, $\theta_\mathrm{E}$ has only an upper limit based on the light curve modeling alone. Additionally, the analysis leads us to identify 8 degenerate configurations: the four-fold microlensing parallax degeneracy being doubled by a degeneracy in the caustic structure present at the level of the ground-based solutions. To pinpoint the physical parameters, and at the same time to break the parallax degeneracy, we make use of a series of arguments: the $\chi^2$ hierarchy, the Rich argument, and a prior Galactic model. The preferred configuration is for a host at $D_L=3.73_{-0.67}^{+0.66}~\mathrm{kpc}$ with mass $M_\mathrm{L}=0.30_{-0.12}^{+0.15}~\mathrm{M_\odot}$, orbited by a Saturn-like planet with $M_\mathrm{planet}=0.43_{-0.17}^{+0.21}~\mathrm{M_\mathrm{Jup}}$ at projected separation $a_\perp = 1.70_{-0.39}^{+0.38}~\mathrm{au}$, about 2.1 times beyond the system snow line. Therefore, it adds to the growing population of sub-Jupiter planets orbiting near or beyond the snow line of M-dwarfs discovered by microlensing. Based on the rules of the real-time protocol for the selection of events to be followed up with Spitzer, this planet will not enter the sample for measuring the Galactic distribution of planets., Comment: Submitted to AAS Journals

Published
2019

40. Spitzer microlensing parallax for OGLE-2017-BLG-0896 reveals a counter-rotating low-mass brown dwarf

Author

G. W. Christie, Chung-Uk Lee, John Southworth, Andrzej Udalski, Sean Carey, Michał K. Szymański, Igor Soszyński, Patryk Iwanek, M. Hundertmark, Yuri I. Fujii, Wei Zhu, In-Gu Shin, Kyu-Ha Hwang, Cheongho Han, Sebastiano Calchi Novati, Radosław Poleski, Seung-Lee Kim, Charles A. Beichman, Jan Skowron, Martin Dominik, Hyoun-Woo Kim, Dong-Jin Kim, Christiane Helling, Sohrab Rahvar, Geoffery Bryden, Valerio Bozza, Simona Ciceri, Yongseok Lee, Markus Rabus, Thiam-Guan Tan, P. Longa-Pena, Yoon-Hyun Ryu, Dan Maoz, Stephen C. Lowry, Michał Pawlak, B. Scott Gaudi, Greg Bolt, Sang-Mok Cha, Rachel Street, B. G. Park, Krzysztof Ulaczyk, Michael D. Albrow, Sun-Ju Chung, U. G. Jørgensen, Jesper Skottfelt, Yiannis Tsapras, Colin Snodgrass, Yossi Shvartzvald, Andrew Gould, Weicheng Zang, J. Campbell-White, Martin Burgdorf, Krzysztof A. Rybicki, Youn Kil Jung, Paweł Pietrukowicz, Richard W. Pogge, Tobias C. Hinse, Szymon Kozłowski, Calen B. Henderson, Tim Natusch, Dong-Joo Lee, Przemek Mróz, Sedighe Sajadian, Daniel F. Evans, Jennifer C. Yee, Etienne Bachelet, University of St Andrews. School of Physics and Astronomy, and University of St Andrews. St Andrews Centre for Exoplanet Science

Subjects
Proper motion, 010504 meteorology & atmospheric sciences, Population, Brown dwarf, bulge [Galaxy], FOS: Physical sciences, gravitational lensing: micro, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Gravitational microlensing, 01 natural sciences, Galaxy: bulge, micro [Gravitational lensing], bulge, gravitational lensing: micro [galaxy], 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, QB Astronomy, education, 010303 astronomy & astrophysics, Astronomy and Astrophysics, Space and Planetary Science, Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics::Galaxy Astrophysics, QC, 0105 earth and related environmental sciences, QB, Physics, education.field_of_study, 3rd-DAS, Galactic plane, Light curve, Galaxy, Radial velocity, QC Physics, Astrophysics - Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, BDC, QB799
Abstract

The kinematics of isolated brown dwarfs in the Galaxy, beyond the solar neighborhood, is virtually unknown. Microlensing has the potential to probe this hidden population, as it can measure both the mass and five of the six phase-space coordinates (all except the radial velocity) even of a dark isolated lens. However, the measurements of both the microlens parallax and finite-source effects are needed in order to recover the full information. Here, we combine $Spitzer$ satellite parallax measurement with the ground-based light curve, which exhibits strong finite-source effects, of event OGLE-2017-BLG-0896. We find two degenerate solutions for the lens (due to the known satellite-parallax degeneracy), which are consistent with each other except for their proper motion. The lens is an isolated brown dwarf with a mass of either $18\pm1M_J$ or $20\pm1M_J$. This is the lowest isolated-object mass measurement to date, only $\sim$45\% more massive than the theoretical deuterium-fusion boundary at solar metallicity, which is the common definition of a free-floating planet. The brown dwarf is located at either $3.9\pm0.1$ kpc or $4.1\pm0.1$ kpc toward the Galactic bulge, but with proper motion in the opposite direction of disk stars, with one solution suggesting it is moving within the Galactic plane. While it is possibly a halo brown dwarf, it might also represent a different, unknown population., 17 pages, 3 figures, 2 tables. Accepted for publication in The Astronomical Journal

Published
2019

41. OGLE-2017-BLG-1186: first application of asteroseismology and Gaussian processes to microlensing

Author

R. Figuera Jaimes, Man Cheung Alex Li, Daniel Huber, Andrew A. Cole, K. H. Hwang, Calen B. Henderson, Masayuki Nagakane, I.-G. Shin, Wei Zhu, Sohrab Rahvar, Yasushi Muraki, Nuno Peixinho, C.-U. Lee, Steve Hennerley, Yuri I. Fujii, M. Rabus, Paul J. Tristram, Yongseok Lee, Andrzej Udalski, G. Bryden, Michał K. Szymański, C. von Essen, Penélope Longa-Peña, Radek Poleski, Atsunori Yonehara, Eduardo Unda-Sanzana, D. J. Lee, Lauri K. Haikala, Szymon Kozłowski, Naoki Koshimoto, Patryk Iwanek, B. S. Gaudi, Julie Green, Przemek Mróz, P. Fouqué, Daniel F. Evans, Thomas Henning, Jennifer C. Yee, M. Hundertmark, J.-P. Beaulieu, Iona Kondo, Richard W. Pogge, Yutaka Matsubara, Martin Dominik, K. Hill, Akihiko Fukui, Nicholas J. Rattenbury, Etienne Bachelet, Jan Skowron, Richard Barry, Tobias C. Hinse, Tianshu Wang, Michael D. Albrow, Igor Soszyński, Krzysztof Ulaczyk, Fumio Abe, Shota Miyazaki, Yoon-Hyun Ryu, S. Calchi Novati, Rachel Street, Aparna Bhattacharya, K. A. Rybicki, Byeong-Gon Park, Martin Donachie, Denis J. Sullivan, J. W. Blackman, J. Drummond, Sedighe Sajadian, Tim Natusch, Sang-Mok Cha, Takahiro Sumi, Martin Burgdorf, Daisuke Suzuki, Andrew Gould, Clément Ranc, Yuki Hirao, Weicheng Zang, Jesper Skottfelt, Yossi Shvartzvald, G. W. Christie, Luigi Mancini, Haruno Suematsu, I. Porritt, Dong-Jin Kim, S. S. Li, Ian A. Bond, John Southworth, D. Maoz, Shude Mao, Sean Carey, David P. Bennett, Yoshitaka Itow, Y. K. Jung, Valerio Bozza, Charles A. Beichman, Hyoun-Woo Kim, Chang S. Han, Colin Snodgrass, Christiane Helling, Paweł Pietrukowicz, Subo Dong, U. G. Jørgensen, Yiannis Tsapras, Seung-Lee Kim, S. J. Chung, University of St Andrews. School of Physics and Astronomy, and University of St Andrews. St Andrews Centre for Exoplanet Science

Subjects
oscillations [stars], Red giant, fundamental parameters [stars], DWARF STARS, Astrophysics, gravitational lensing: micro, 01 natural sciences, STANDARD, Angular diameter, Bulge, QB460, PROGRAM, QB Astronomy, Astrophysics::Solar and Stellar Astrophysics, 010303 astronomy & astrophysics, QB, Earth and Planetary Astrophysics (astro-ph.EP), Physics, PLANET PHOTOMETRY, 3rd-DAS, Astrophysics - Solar and Stellar Astrophysics, stars: fundamental parameters, stars: oscillations, Astrophysics::Earth and Planetary Astrophysics, astro-ph.SR, STELLAR OSCILLATIONS, Brown dwarf, FOS: Physical sciences, asteroseismology, Astrophysics::Cosmology and Extragalactic Astrophysics, SUBGIANTS, Gravitational microlensing, Asteroseismology, Settore FIS/05 - Astronomia e Astrofisica, ANGULAR SIZES, SYSTEMS, 0103 physical sciences, Solar and Stellar Astrophysics (astro-ph.SR), DISTANCES, Astrophysics::Galaxy Astrophysics, 010308 nuclear & particles physics, Astronomy and Astrophysics, Light curve, SURFACE BRIGHTNESS RELATIONS, Space and Planetary Science, astro-ph.EP, micro [gravitational lensing], Parallax, QB799, Astrophysics - Earth and Planetary Astrophysics
Abstract

著者人数: 105名 (所属. 宇宙航空研究開発機構宇宙科学研究所(JAXA)(ISAS): 鈴木, 大介), Number of authors: 105 (Affiliation. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency(JAXA)(ISAS): Suzuki, Daisuke), Accepted: 2019-07-03, 資料番号: SA1190108000

Published
2019

42. Wide-Orbit Exoplanet Demographics

Author

Bennett, David P., Rachel Akeson, Yann Alibert, Jay Anderson, Etienne Bachelet, Jean-Phillipe Beaulieu, Andrea Bellini, Aparna Bhattacharya, Alan Boss, Valerio Bozza, Stephen Bryson, Derek Buzasi, Sebastiano Calchi Novati, Jessie Christiansen, Domagal-Goldman, Shawn D., Michael Endl, Fulton, Benjamin J., Henderson, Calen B., Scott Gaudi, B., Johnson, Samson A., Naoki Koshimoto, Michael Meyer, Mulders, Gijs D., Susan Mullally, Ruth Murray-Clay, David Nataf, Eric Nielsen, Henry Ngo, Ilaria Pascucci, Matthew Penny, Peter Plavchan, Radek Poleski, Clement Ranc, Raymond, Sean N., Leslie Rogers, Johannes Sahlmann, Sahu, Kailash C., Joshua Schlieder, Yossi Shvartzvald, Alessandro Sozzetti, Rachel Street, Takahiro Sumi, Daisuke Suzuki, Neil Zimmerman, Laboratoire d'astrophysique de l'observatoire de Besançon (UMR 6091) (LAOB), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC), Institut de recherche en astrophysique et planétologie (IRAP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), McDonald Observatory, University of Texas at Austin [Austin], Liquides Ioniques et Interfaces Chargées (LI2C), Université Pierre et Marie Curie - Paris 6 (UPMC)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), ECLIPSE 2019, Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), and Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Earth and Planetary Astrophysics (astro-ph.EP), Astrophysics::Instrumentation and Methods for Astrophysics, [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], FOS: Physical sciences, Astrophysics::Earth and Planetary Astrophysics, Astrophysics - Earth and Planetary Astrophysics
Abstract

The Kepler, K2 and TESS transit surveys are revolutionizing our understanding of planets orbiting close to their host stars and our understanding of exoplanet systems in general, but there remains a gap in our understanding of wide-orbit planets. This gap in our understanding must be filled if we are to understand planet formation and how it affects exoplanet habitability. We summarize current and planned exoplanet detection programs using a variety of methods: microlensing (including WFIRST), radial velocities, Gaia astrometry, and direct imaging. Finally, we discuss the prospects for joint analyses using results from multiple methods and obstacles that could hinder such analyses. We endorse the findings and recommendations published in the 2018 National Academy report on Exoplanet Science Strategy. This white paper extends and complements the material presented therein., Astro2020 Science White paper

Published
2019

43. KELT-22Ab: A Massive, Short-Period Hot Jupiter Transiting a Near-solar Twin

Author

Marshall C. Johnson, Joshua Pepper, David Kasper, Michael L. Calkins, Denise C. Stephens, Nate McCrady, Eric L. N. Jensen, Ivan A. Curtis, Perry Berlind, Jason D. Eastman, Dax L. Feliz, Valerio Bozza, Kim K. McLeod, David H. Cohen, Xinyu Yao, Thomas G. Beatty, Steven Villanueva, Thomas E. Oberst, David J. James, Thiam-Guan Tan, George Zhou, Rudolf B. Kuhn, Keivan G. Stassun, Amber Malpas, Phillip A. Reed, Benjamin J. Fulton, Phil Evans, John Asher Johnson, Robert J. Siverd, Joseph E. Rodriguez, Jonathan Labadie-Bartz, Samson A. Johnson, Matthew T. Penny, David H. Sliski, B. Scott Gaudi, Daniel Bayliss, Jason T. Wright, Michael D. Albrow, Howard M. Relles, Joao Bento, David R. Ciardi, Gilbert A. Esquerdo, Michael D. Joner, David W. Latham, John F. Kielkopf, Knicole D. Colón, Mark Manner, Roberto Zambelli, Daniel J. Stevens, Allyson Bieryla, Karen A. Collins, Kaloyan Penev, Joao Gregorio, Robert A. Wittenmyer, Michael B. Lund, and Chris Stockdale

Subjects
Physics, planets and satellites: detection, 010504 meteorology & atmospheric sciences, Astronomy, Astronomy and Astrophysics, 01 natural sciences, Methods observational, planets and satellites: gaseous planets, techniques: photometric, Space and Planetary Science, techniques: radial velocities, 0103 physical sciences, Hot Jupiter, methods: observational, techniques: spectroscopic, Period (geology), 010303 astronomy & astrophysics, 0105 earth and related environmental sciences
Abstract

We present the discovery of KELT-22Ab, a hot Jupiter from the KELT-South survey. KELT-22Ab transits the moderately bright (V∼11.1) Sun-like G2V star TYC 7518-468-1. The planet has an orbital period of P = 1.3866529±0.0000027 days, a radius of R_P = 1.285^(+0.12)_(−0.071) R_J, and a relatively large mass of M_P = 3.47^(+0.15)_(−0.14) M_J. The star has R⋆ = 1.099^(+0.079)_(−0.046) R⊙, M⋆ = 1.092^(+0.045)_(−0.041) M⊙, T_(eff) = 5767^(+50)_(−49) K, log g⋆ = 4.393^(+0.039)_(−0.060) (cgs), and [m/H] = +0.259^(+0.085)_(−0.083), and thus, other than its slightly super-solar metallicity, appears to be a near solar twin. Surprisingly, KELT-22A exhibits kinematics and a Galactic orbit that are somewhat atypical for thin disk stars. Nevertheless, the star is rotating quite rapidly for its estimated age, shows evidence of chromospheric activity, and is somewhat metal rich. Imaging reveals a slightly fainter companion to KELT-22A that is likely bound, with a projected separation of 6” (∼1400 AU). In addition to the orbital motion caused by the transiting planet, we detect a possible linear trend in the radial velocity of KELT-22A suggesting the presence of another relatively nearby body that is perhaps non-stellar. KELT-22Ab is highly irradiated (as a consequence of the small semi-major axis of a/R⋆ = 4.97), and is mildly inflated. At such small separations, tidal forces become significant. The configuration of this system is optimal for measuring the rate of tidal dissipation within the host star. Our models predict that, due to tidal forces, the semi-major axis of KELT-22Ab is decreasing rapidly, and is thus predicted to spiral into the star within the next Gyr.

Published
2019

44. OGLE-2014-BLG-1186: Gravitational microlensing providing evidence for a planet orbiting the foreground star or for a close binary source?

Author

Luigi Mancini, Łukasz Wyrzykowski, J. W. Menzies, D. M. Bramich, C. Han, Colin Snodgrass, Sohrab Rahvar, M. Hundertmark, Jean Surdej, P. Mróz, Etienne Bachelet, Gaetano Scarpetta, Joachim Wambsganss, Diana Juncher, Jesper Skottfelt, Olivier Wertz, Troels Haugbølle, A. Popovas, P. Pietrukowicz, Radosław Poleski, R. W. Schmidt, S. Kozlowski, U. G. Jørgensen, Yiannis Tsapras, Martin Dominik, N. Kains, D. A. Starkey, S. Calchi Novati, Jan Skowron, Valerio Bozza, Andrzej Udalski, Michał K. Szymański, Tobias C. Hinse, Krzysztof Ulaczyk, Iain A. Steele, Markus Rabus, Keith Horne, Simona Ciceri, Rachel Street, R. Figuera Jaimes, Giuseppe D'Ago, Khalid Al-Subai, Igor Soszyński, Heidi Korhonen, John Southworth, Science & Technology Facilities Council, University of St Andrews. School of Physics and Astronomy, and University of St Andrews. St Andrews Centre for Exoplanet Science

Subjects
planets and satellites: detection, detection [planets and satellites], Binary number, Astrophysics, gravitational lensing: micro, 01 natural sciences, Planet, QB460, QB Astronomy, Astrophysics::Solar and Stellar Astrophysics, micro, (stars:) binaries: eclipsing, Galaxy: kinematics and dynamics, methods: data analysis, methods: statistical [gravitational lensing], 010303 astronomy & astrophysics, QC, QB, Physics, Earth and Planetary Astrophysics (astro-ph.EP), ) binaries: eclipsing [(stars], 3rd-DAS, Astrophysics - Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics, methods: statistical, statistical [methods], FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Gravitational microlensing, Photometry (optics), Settore FIS/05 - Astronomia e Astrofisica, 0103 physical sciences, data analysis [methods], Instrumentation and Methods for Astrophysics (astro-ph.IM), Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics::Galaxy Astrophysics, 010308 nuclear & particles physics, Astronomy and Astrophysics, kinematics and dynamics [Galaxy], Light curve, Noise floor, Astrophysics - Astrophysics of Galaxies, Stars, QC Physics, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), micro [gravitational lensing], Parallax, Astrophysics - Earth and Planetary Astrophysics, QB799
Abstract

(abridged) Using the particularly long gravitational microlensing event OGLE-2014-BLG-1186 with a time-scale $t_\mathrm{E}$ ~ 300 d, we present a methodology for identifying the nature of localised deviations from single-lens point-source light curves, which ensures that 1) the claimed signal is substantially above the noise floor, 2) the inferred properties are robustly determined and their estimation not subject to confusion with systematic noise in the photometry, 3) there are no alternative viable solutions within the model framework that might have been missed. Annual parallax and binarity could be separated and robustly measured from the wing and the peak data, respectively. We find matching model light curves that involve either a binary lens or a binary source. Our binary-lens models indicate a planet of mass $M_2$ = (45 $\pm$ 9) $M_\oplus$, orbiting a star of mass $M_1$ = (0.35 $\pm$ 0.06) $M_\odot$, located at a distance $D_\mathrm{L}$ = (1.7 $\pm$ 0.3) kpc from Earth, whereas our binary-source models suggest a brown-dwarf lens of $M$ = (0.046 $\pm$ 0.007) $M_\odot$, located at a distance $D_\mathrm{L}$ = (5.7 $\pm$ 0.9) kpc, with the source potentially being a (partially) eclipsing binary involving stars predicted to be of similar colour given the ratios between the luminosities and radii. The ambiguity in the interpretation would be resolved in favour of a lens binary by observing the luminous lens star separating from the source at the predicted proper motion of $\mu$ = (1.6 $\pm$ 0.3) mas yr$^{-1}$, whereas it would be resolved in favour of a source binary if the source could be shown to be a (partially) eclipsing binary matching the obtained model parameters. We experienced that close binary source stars pose a challenge for claiming the detection of planets by microlensing in events where the source passes very close to the lens star hosting the planet., Comment: 26 pages, 14 figures

Published
2019

45. VBbinarylensing : a public package for microlensing light-curve computation

Author

Ava R. Hoag, Valerio Bozza, M. Hundertmark, Etienne Bachelet, Fran Bartolić, T. M. Heintz, University of St Andrews. St Andrews Centre for Exoplanet Science, and University of St Andrews. School of Physics and Astronomy

Subjects
Computation, Decision tree, Gravitational lensing, FOS: Physical sciences, General Relativity and Quantum Cosmology (gr-qc), Gravitational microlensing, 01 natural sciences, Bottleneck, Field (computer science), General Relativity and Quantum Cosmology, numerical, Micro -methods, 0103 physical sciences, Code (cryptography), micro -methods, Astronomy and Astrophysics, Space and Planetary Science, QB Astronomy, Instrumentation and Methods for Astrophysics (astro-ph.IM), 010303 astronomy & astrophysics, QC, QB, Earth and Planetary Astrophysics (astro-ph.EP), Physics, Numerical, 010308 nuclear & particles physics, DAS, Light curve, Methods of contour integration, QC Physics, Astrophysics - Instrumentation and Methods for Astrophysics, Algorithm, Astrophysics - Earth and Planetary Astrophysics
Abstract

The computation of microlensing light curves represents a bottleneck for the modeling of planetary events, making broad searches in the vast parameter space of microlensing extremely time-consuming. The release of the first version of VBBinaryLensing (based on the advanced contour integration method presented in Bozza(2010)) has represented a considerable advance in the field, with the birth of several analysis platforms running on this code. Here we present the version 2.0 of VBBinaryLensing, which contains several upgrades with respect to the first version, including new decision trees that introduce important optimizations in the calculations., 12 pages, 7 figures

Published
2018

46. OGLE-2017-BLG-0329L: A Microlensing Binary Characterized with Dramatically Enhanced Precision Using Data from Space-based Observations

Author

Christiane Helling, Jennifer C. Yee, Sedighe Sajadian, D. J. Lee, Richard W. Pogge, Stephen C. Lowry, Byeong-Gon Park, Yoon-Hyun Ryu, Shinyoung Kim, Patryk Iwanek, Tobias C. Hinse, B. S. Gaudi, Krzysztof Ulaczyk, Igor Soszyński, Andrew Gould, Weicheng Zang, Sohrab Rahvar, Dong-Jin Kim, Geoffrey Bryden, Charles A. Beichman, Radosław Poleski, Kyu-Ha Hwang, Jan Skowron, In-Gu Shin, S. Kozłowski, Paweł Pietrukowicz, S. Calchi Novati, Sang-Mok Cha, Calen B. Henderson, Chang S. Han, Michael D. Albrow, U. G. Jørgensen, Daniel F. Evans, Yossi Shvartzvald, Martin Dominik, Colin Snodgrass, Przemek Mróz, J. Campbell-White, Woong-Tae Kim, M. Hundertmark, C.-U. Lee, Hyo-Ryoung Kim, Martin Burgdorf, Krzysztof A. Rybicki, Valerio Bozza, Wei Zhu, Markus Rabus, Sean Carey, S. J. Chung, Andrzej Udalski, Michał K. Szymański, Yongseok Lee, Youn Kil Jung, Simona Ciceri, Lauri K. Haikala, M. Pawlak, Penélope Longa-Peña, University of St Andrews. School of Physics and Astronomy, and University of St Andrews. St Andrews Centre for Exoplanet Science

Subjects
010504 meteorology & atmospheric sciences, FOS: Physical sciences, Binary number, Astrophysics, gravitational lensing: micro, Space (mathematics), Gravitational microlensing, 01 natural sciences, micro [Gravitational lensing], Einstein radius, Gravitation, 0103 physical sciences, QB460, QB Astronomy, 010303 astronomy & astrophysics, QC, Solar and Stellar Astrophysics (astro-ph.SR), QB, 0105 earth and related environmental sciences, Physics, general [Binaries], DAS, Astronomy and Astrophysics, binaries: general, Space and Planetary Science, QC Physics, Astrophysics - Solar and Stellar Astrophysics, Caustic (optics), Degeneracy (mathematics), Parallax
Abstract

Mass measurements of gravitational microlenses require one to determine the microlens parallax $\pie$, but precise $\pie$ measurement, in many cases, is hampered due to the subtlety of the microlens-parallax signal combined with the difficulty of distinguishing the signal from those induced by other higher-order effects. In this work, we present the analysis of the binary-lens event OGLE-2017-BLG-0329, for which $\pie$ is measured with a dramatically improved precision using additional data from space-based $Spitzer$ observations. We find that while the parallax model based on the ground-based data cannot be distinguished from a zero-$\pie$ model at 2$\sigma$ level, the addition of the $Spitzer$ data enables us to identify 2 classes of solutions, each composed of a pair of solutions according to the well-known ecliptic degeneracy. It is found that the space-based data reduce the measurement uncertainties of the north and east components of the microlens-parallax vector $\pivec_{\rm E}$ by factors $\sim 18$ and $\sim 4$, respectively. With the measured microlens parallax combined with the angular Einstein radius measured from the resolved caustic crossings, we find that the lens is composed of a binary with components masses of either $(M_1,M_2)\sim (1.1,0.8)\ M_\odot$ or $\sim (0.4,0.3)\ M_\odot$ according to the two solution classes. The first solution is significantly favored but the second cannot be securely ruled out based on the microlensing data alone. However, the degeneracy can be resolved from adaptive optics observations taken $\sim 10$ years after the event., Comment: 9 pages, 4 tables, 6 figures

Published
2018

47. OGLE-2017-BLG-0482Lb: A Microlensing Super-Earth Orbiting a Low-mass Host Star

Author

Woong-Tae Kim, Krzysztof Ulaczyk, Igor Soszyński, Richard Barry, Yasushi Muraki, In-Gu Shin, Yongseok Lee, Atsunori Yonehara, Aparna Bhattacharya, Paul J. Tristram, S. Kozlowski, Akihiko Fukui, T. Yamada, Przemek Mróz, Patryk Iwanek, Wei Zhu, Kyu-Ha Hwang, Michał Pawlak, Doeon Kim, Valerio Bozza, To. Saito, Kohei Kawasaki, Krzysztof A. Rybicki, Nicholas J. Rattenbury, Jan Skowron, Andrew Gould, Clément Ranc, Yoon-Hyun Ryu, Shota Miyazaki, Phil Evans, Hyoun-Woo Kim, Masayuki Nagakane, Y. K. Jung, Daisuke Suzuki, H. Munakata, Jennifer C. Yee, Shinyoung Kim, Takahiro Sumi, S. J. Chung, Radek Poleski, Byeong-Gon Park, David P. Bennett, Ian A. Bond, D.-J. Kim, Fumio Abe, Andrzej Udalski, Michał K. Szymański, C.-U. Lee, Paweł Pietrukowicz, Yuki Hirao, Yoshitaka Itow, Yossi Shvartzvald, Naoki Koshimoto, Sang-Mok Cha, C. H. Ling, Michael D. Albrow, Duk-Hang Lee, Martin Donachie, Denis J. Sullivan, Richard W. Pogge, Yutaka Matsubara, Man Cheung Alex Li, K. Ohnishi, C. Han, and A. Sharan

Subjects
Earth and Planetary Astrophysics (astro-ph.EP), Physics, 010504 meteorology & atmospheric sciences, FOS: Physical sciences, Library science, Astronomy and Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, gravitational lensing: micro, planetary systems, Space and Planetary Science, Gravitational microlensing, 01 natural sciences, Internet service, 0103 physical sciences, Astrophysics::Earth and Planetary Astrophysics, Space Science, Space research, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences, Astrophysics - Earth and Planetary Astrophysics
Abstract

著者人数: 65名ほか (所属. 宇宙航空研究開発機構宇宙科学研究所(JAXA)(ISAS): 鈴木, 大介), Accepted: 2018-03-27, 資料番号: SA1180046000

Published
2018

48. OGLE-2016-BLG-1190Lb: The First Spitzer Bulge Planet Lies Near the Planet/Brown-dwarf Boundary

Author

Yuki Hirao, Yossi Shvartzvald, Kimiaki Masuda, Hyoun-Woo Kim, Chang S. Han, B. S. Gaudi, Colin Snodgrass, R. W. Schmidt, I.-G. Shin, Z. Li, Sang-Mok Cha, Kouji Ohnishi, Sohrab Rahvar, Shinyoung Kim, S. J. Chung, Yoon-Hyun Ryu, Simon Cross, C.-U. Lee, Ian A. Bond, Masayuki Nagakane, G. Bryden, Matthew T. Penny, Calen B. Henderson, P. Mróz, S. Calchi Novati, Paul J. Tristram, J. MacKenzie, S. Kozlowski, Andrzej Udalski, Nicholas J. Rattenbury, C. von Essen, Michał K. Szymański, Jan Skowron, M. Hundertmark, A. Popovas, P. Pietrukowicz, Jennifer C. Yee, P. Longa, Y. K. Jung, Radosław Poleski, Naoki Koshimoto, Valerio Bozza, Richard K. Barry, Savannah Jacklin, C. H. Ling, Etienne Bachelet, Yasushi Muraki, Fumio Abe, C. A. Beichman, Rachel Street, Tianshu Wang, Shota Miyazaki, Yongseok Lee, Markus Rabus, Sedighe Sajadian, David P. Bennett, Atsunori Yonehara, Martin Donachie, Denis J. Sullivan, To. Saito, Man Cheung Alex Li, Daniel F. Evans, Kohei Kawasaki, Yoshitaka Itow, D. Maoz, R. Figuera Jaimes, Martin Dominik, Keith Horne, Joachim Wambsganss, Phil Evans, Iain A. Steele, Takahiro Sumi, A. Bhattacharya, Steve B. Howell, Simona Ciceri, Akihiko Fukui, Byeong-Gon Park, Dong-Joo Lee, U. G. Jørgensen, Yiannis Tsapras, John Southworth, Chelsea X. Huang, Igor Soszyński, Eamonn Kerins, Sean Carey, Wei Zhu, Kyu-Ha Hwang, Giuseppe D'Ago, Shude Mao, T. Yamada, Richard W. Pogge, Yutaka Matsubara, Tobias C. Hinse, D.-J. Kim, Krzysztof Ulaczyk, Daisuke Suzuki, M. Pawlak, Arnaud Cassan, Jesper Skottfelt, Yuichiro Asakura, S. K. Ment, Andrew Gould, Clément Ranc, Weicheng Zang, Michael D. Albrow, A. Sharan, Rosita Kokotanekova, Martin Burgdorf, Pascal Fouqué, Science & Technology Facilities Council, University of St Andrews. St Andrews Centre for Exoplanet Science, and University of St Andrews. School of Physics and Astronomy

Subjects
Gas giant, GRAVITATIONAL LENSING EXPERIMENT, Brown dwarf, FOS: Physical sciences, gravitational lensing: micro, Astrophysics::Cosmology and Extragalactic Astrophysics, Cathie Marsh Institute, Gravitational microlensing, 01 natural sciences, EARTH-MASS, MAGNIFICATION MICROLENSING EVENTS, JUPITER/SATURN ANALOG, micro [Gravitational lensing], 3rd-NDAS, GAS GIANTS, SYSTEMS, Bulge, Planet, QB460, 0103 physical sciences, PHOTOMETRY, QB Astronomy, Astrophysics::Solar and Stellar Astrophysics, 010303 astronomy & astrophysics, QC, Astrophysics::Galaxy Astrophysics, QB, Earth and Planetary Astrophysics (astro-ph.EP), Physics, 010308 nuclear & particles physics, Astronomy, Astronomy and Astrophysics, MASS PLANET, Earth mass, Orbital period, TIME, micro, Astrophysics - Earth and Planetary Astrophysics [gravitational lensing], Stars, Space and Planetary Science, ResearchInstitutes_Networks_Beacons/cathie_marsh_institute, Astrophysics::Earth and Planetary Astrophysics, STARS, Astrophysics - Earth and Planetary Astrophysics
Abstract

著者人数: 110名(JAXA職員: 鈴木, 大介), Accepted: 2017-11-17, 資料番号: SA1170210000

Published
2018

49. The KELT Follow-up Network and Transit False-positive Catalog: Pre-vetted False Positives for TESS

Author

Phillip A. Reed, Eric L. N. Jensen, Alex D. Spencer, Caroline Odden, Joshua Pepper, Trevor J. Martin, Romina Petrucci, Dax L. Feliz, Siramas Komonjinda, Rex R. Yeigh, Knicole D. Colón, Tolga Gumusayak, G. F. Aldi, Robert J. Siverd, Simon J. Lowther, Steven Villanueva, Daniel A. Hancock, Tyler G. Ellis, Thiam-Guan Tan, George Zhou, Michael D. Joner, Steve Rau, Kevin I. Collins, Daniel J. Stevens, Ian R. Clark, David W. Latham, Phil Evans, Elizabeth Warner, Courtney D. Dressing, Joseph E. Rodriguez, Peter A. Panka, Hannah Jang-Condell, Daniel Bayliss, David R. Ciardi, Keivan G. Stassun, Rebecca L. Sorber, Rudolf B. Kuhn, Zach Berta-Thompson, Gilbert A. Esquerdo, Erica Ellingson, Franky Dubois, Dennis M. Conti, Perry Berlind, B. Scott Gaudi, Joe P. Renaud, Eric G. Hintz, Alison J. Friedli, David H. Cohen, Emiliano Jofré, John F. Kielkopf, Roberto Zambelli, Jonathan Labadie-Bartz, Özgür Baştürk, Rhodes Hart, Paul Benni, Thomas E. Oberst, Justin R. Crepp, Mark Trueblood, Joao Bento, Cliff Ashcraft, Supachai Awiphan, Michael B. Lund, Gaetano Scarpetta, Chris Stockdale, David Baker, Siegfried Vanaverbeke, John C. Good, Matthew T. Penny, Xinyu Yao, Jim Nordhausen, Caleb K. Harada, Samuel N. Quinn, Valerio Bozza, Mary Lou West, Patricia Trueblood, Elizabeth J. Jeffery, G. Bruce Berriman, M. Spencer, Michael L. Calkins, Aman Kar, Selçuk Yalçınkaya, Giuseppe D'Ago, Jenna M. Cann, Jacob Leuquire, Cliff Kotnik, Akihiko Fukui, Phillip J. MacQueen, Erica J. Gonzales, Thomas G. Beatty, Sebastiano Calchi Novati, Allyson Bieryla, William D. Cochran, David James, Joao Gregorio, Mundra Akshay, Burak Keten, Kenny A. Diazeguigure, Peter Plavchan, Ivan A. Curtis, Howard M. Relles, Gabriel Murawski, Kim K. McLeod, Norio Narita, Marshall C. Johnson, David Kasper, Denise C. Stephens, Tiffany R. Lewis, Ludwig Logie, Dimitri Mawet, Karen A. Collins, and Benjamin J. Fulton

Subjects
Point spread function, 010504 meteorology & atmospheric sciences, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, law.invention, Telescope, Planet, law, 0103 physical sciences, False positive paradox, Astrophysics::Solar and Stellar Astrophysics, Transit (astronomy), 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences, Earth and Planetary Astrophysics (astro-ph.EP), Physics, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy, Astronomy and Astrophysics, Light curve, Exoplanet, Stars, Space and Planetary Science, Astrophysics::Earth and Planetary Astrophysics, Astrophysics - Earth and Planetary Astrophysics
Abstract

The Kilodegree Extremely Little Telescope (KELT) project has been conducting a photometric survey for transiting planets orbiting bright stars for over ten years. The KELT images have a pixel scale of ~23"/pixel---very similar to that of NASA's Transiting Exoplanet Survey Satellite (TESS)---as well as a large point spread function, and the KELT reduction pipeline uses a weighted photometric aperture with radius 3'. At this angular scale, multiple stars are typically blended in the photometric apertures. In order to identify false positives and confirm transiting exoplanets, we have assembled a follow-up network (KELT-FUN) to conduct imaging with higher spatial resolution, cadence, and photometric precision than the KELT telescopes, as well as spectroscopic observations of the candidate host stars. The KELT-FUN team has followed-up over 1,600 planet candidates since 2011, resulting in more than 20 planet discoveries. Excluding ~450 false alarms of non-astrophysical origin (i.e., instrumental noise or systematics), we present an all-sky catalog of the 1,128 bright stars (6, Comment: Accepted for publication in AJ, 21 pages, 12 figures, 7 tables

Published
2018

50. OGLE-2014-BLG-0289: Precise Characterization of a Quintuple-peak Gravitational Microlensing Event

Author

Daisuke Suzuki, Paul J. Tristram, Wei Zhu, Chas Beichman, M. Hundertmark, Woong-Tae Kim, Fumio Abe, T. Yamada, Man Cheung Alex Li, Igor Soszyński, To. Saito, Cheongho Han, R. Figuera Jaimes, Richard Barry, Akihiko Fukui, S. Calchi Novati, C. H. Ling, S. Kozłowski, N. Kains, Giuseppe D'Ago, In-Gu Shin, Przemek Mróz, Richard W. Pogge, Kouji Ohnishi, Paweł Pietrukowicz, Yutaka Matsubara, Joachim Wambsganss, A. Sharan, Masayuki Nagakane, Jennifer C. Yee, Phil Evans, Andrew Gould, Valerio Bozza, Yasushi Muraki, Radosław Poleski, Naoki Koshimoto, Atsunori Yonehara, Krzysztof Ulaczyk, H. Munakata, Keith Horne, Etienne Bachelet, Clément Ranc, Nicholas J. Rattenbury, Jan Skowron, David P. Bennett, Takahiro Sumi, Andrzej Udalski, Michał K. Szymański, Sean Carey, Martin Donachie, Denis J. Sullivan, Yoshitaka Itow, Martin Dominik, Iain A. Steele, Łukasz Wyrzykowski, Yuki Hirao, Aparna Bhattacharya, Shota Miyazaki, Kohei Kawasaki, D. M. Bramich, Youn Kil Jung, Ian A. Bond, Kimiaki Masuda, J. W. Menzies, Colin Snodgrass, R. W. Schmidt, University of St Andrews. School of Physics and Astronomy, and University of St Andrews. St Andrews Centre for Exoplanet Science

Subjects
FOS: Physical sciences, Astrophysics, gravitational lensing: micro, Gravitational microlensing, 01 natural sciences, Einstein radius, law.invention, micro [Gravitational lensing], law, 0103 physical sciences, QB Astronomy, 010303 astronomy & astrophysics, QC, Solar and Stellar Astrophysics (astro-ph.SR), QB, Cusp (singularity), Physics, general [Binaries], 010308 nuclear & particles physics, DAS, Astronomy and Astrophysics, Light curve, binaries: general, Space and Planetary Science, Lens (optics), QC Physics, Astrophysics - Solar and Stellar Astrophysics, Caustic (optics), Parallax, Event (particle physics)
Abstract

著者人数: 66名(所属. 宇宙航空研究開発機構宇宙科学研究所(JAXA)(ISAS): 鈴木, 大介), Accepted: 2017-12-11, 資料番号: SA1170274000

Published
2018

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