Results 1 to 10 of about 351 (182)

Demagnifying Gravitational Lenses as Probes of Dark Matter Structures and Nonminimal Couplings to Gravity

The Astrophysical Journal Letters
Magnification of total image fluxes is typically considered a defining feature of gravitational microlensing. In contrast, I will show that nonminimal couplings to gravity can generate regions of negative gravitational potential curvature, giving rise to
Hong-Yi Zhang
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Four Planets Found through Microlensing Events Involving Faint Source Stars

The Astronomical Journal
To conduct a comprehensive demographic study of microlensing planets, it is essential to detect all planetary signals that exceed a predefined threshold through a detailed analysis of survey data.
Cheongho Han, Michael D. Albrow, Chung-Uk Lee, Sun-Ju Chung, Andrew Gould, Kyu-Ha Hwang, Youn Kil Jung, Yoon-Hyun Ryu, Yossi Shvartzvald, In-Gu Shin, Jennifer C. Yee, Hongjing Yang, Weicheng Zang, Sang-Mok Cha, Doeon Kim, Dong-Jin Kim, Seung-Lee Kim, Dong-Joo Lee, Yongseok Lee, Byeong-Gon Park, Richard W. Pogge   +20 more
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Systematic KMTNet Planetary Anomaly Search. XII. Complete Sample of 2017 Subprime Field Planets

The Astronomical Journal
We report the analysis of four unambiguous planets and one possible planet from the subprime fields (Γ ≤ 1 hr ^−1 ) of the 2017 Korea Microlensing Telescope Network (KMTNet) microlensing survey, to complete the KMTNet AnomalyFinder planetary sample for ...
Yuqian Gui, Weicheng Zang, Ruocheng Zhai, Yoon-Hyun Ryu, Andrzej Udalski, Hongjing Yang, Cheongho Han, Shude Mao, Leading Authors, Michael D. Albrow, Sun-Ju Chung, Andrew Gould, Kyu-Ha Hwang, Youn Kil Jung, In-Gu Shin, Yossi Shvartzvald, Jennifer C. Yee, Sang-Mok Cha, Dong-Jin Kim, Hyoun-Woo Kim, Seung-Lee Kim, Chung-Uk Lee, Dong-Joo Lee, Yongseok Lee, Byeong-Gon Park, Richard W. Pogge, The KMTNet Collaboration, Przemek Mróz, Michał K. Szymański, Jan Skowron, Radosław Poleski, Igor Soszyński, Paweł Pietrukowicz, Szymon Kozłowski, Krzysztof Ulaczyk, Krzysztof A. Rybicki, Patryk Iwanek, Marcin Wrona, Mariusz Gromadzki, The OGLE Collaboration, Hanyue Wang, Jiyuan Zhang, Renkun Kuang, Qiyue Qian, Wei Zhu, The MAP Collaboration   +45 more
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Astrophysical implications of gravitational microlensing of gravitational waves [PDF]

Astronomy & Astrophysics, 2001
Astrophysical implications of gravitational microlensing of gravitational waves emitted by rotating neutron stars (NSs) are investigated. In particular, attention is focused on the following situations: i) NSs in the galactic bulge lensed by a central black hole of $2.6\times 10^6 M_{\odot}$ or by stars and MACHOs distributed in the galactic bulge ...
DE PAOLIS, Francesco, INGROSSO, Gabriele, NUCITA, Achille   +2 more
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Primordial Black Hole Dark Matter Simulations Using PopSyCLE

The Astrophysical Journal
Primordial black holes (PBHs), theorized to have originated in the early Universe, are speculated to be a viable form of dark matter. If they exist, they should be detectable through photometric and astrometric signals resulting from gravitational ...
Kerianne Pruett, William Dawson, Michael S. Medford, Jessica R. Lu, Casey Lam, Scott Perkins, Peter McGill, Nathan Golovich, George Chapline   +8 more
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GRAVITATIONAL MICROLENSING OF RING-LIKE SOURCES

Bulletin of Taras Shevchenko National University of Kyiv. Astronomy, 2023
Background. Ring-like structures may appear in some images of accretion disks around relativistic compact objects, which represent a possible alternative to conventional black holes. We present a qualitative treatment of photometric microlensing effects in case of such structures. Methods.
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KMT-2022-BLG-1818Lb,c: A Cold Super-Jupiter with a Saturn Sibling

The Astronomical Journal
We present the discovery and analysis of the sixth microlensing two-planet system, KMT-2022-BLG-1818Lb,c, detected by a follow-up program targeting high-magnification events.
Hongyu Li, Jiyuan Zhang, Cheongho Han, Weicheng Zang, Youn Kil Jung, Andrzej Udalski, Takahiro Sumi, Hongjing Yang, Renkun Kuang, Shude Mao, (Leading Authors), Michael D. Albrow, Sun-Ju Chung, Andrew Gould, Kyu- Ha Hwang, Yoon-Hyun Ryu, In-Gu Shin, Yossi Shvartzvald, Jennifer C. Yee, 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), Berto Monard, Yunyi Tang, Subo Dong, Zhuokai Liu, Grant Christie, Jennie McCormick, Tim Natusch, Qiyue Qian, Dan Maoz, Wei Zhu, (The MAP and µFUN Follow-up Team), Przemek Mróz, Michał K. Szymański, Jan Skowron, Radoslaw Poleski, Igor Soszyński, Paweł Pietrukowicz, Szymon Kozłowski, Krzysztof A. Rybicki, Patryk Iwanek, Krzysztof Ulaczyk, Marcin Wrona, Mariusz Gromadzki, Mateusz J. Mróz, (The OGLE Collaboration), Fumio Abe, Ken Bando, David P. Bennett, Aparna Bhattacharya, Ian A. Bond, Akihiko Fukui, Ryusei Hamada, Shunya Hamada, Naoto Hamasak, Yuki Hirao, Stela Ishitani Silva, Naoki Koshimoto, Yutaka Matsubara, Shota Miyazaki, Yasushi Muraki, Tutumi Nagai, Kansuke Nunota, Greg Olmschenk, Clément Ranc, Nicholas J. Rattenbury, Yuki Satoh, Daisuke Suzuki, Sean Terry, Paul J. Tristram, Aikaterini Vandorou, Hibiki Yama, (The MOA Collaboration)   +79 more
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Gravitational microlensing: Results and perspectives in brief [PDF]

Physics of Particles and Nuclei, 2008
8 pages, 1 figure, An invited lecture at the Helmholtz International Summer School "Dense Matter in Heavy Ion Collisions and Astrophysics", Bogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, Dubna, Russia, August 21 - September 1, 2006, added reference, corrected ...
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KMT-2022-BLG-0086: Another Binary-lens Binary-source Microlensing Event

The Astronomical Journal
We present the analysis of a microlensing event KMT-2022-BLG-0086 of which the overall light curve is not described by a binary-lens single-source (2L1S) model, which suggests the existence of an extra lens or an extra source.
Sun-Ju Chung, Kyu-Ha Hwang, Jennifer C. Yee, Andrew Gould, Ian A. Bond, Hongjing Yang, (Leading Authors), Michael D. Albrow, Youn Kil Jung, Cheongho Han, Yoon-Hyun Ryu, In-Gu Shin, Yossi Shvartzvald, 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), Fumio Abe, David P. Bennett, Aparna Bhattacharya, Akihiko Fukui, Ryusei Hamada, Yuki Hirao, Stela Ishitani Silva, Naoki Koshimoto, Shota Miyazaki, Yasushi Muraki, Tutumi Nagai, Kansuke Nunota, Greg Olmschenk, Clément Ranc, Nicholas J. Rattenbury, Yuki Satoh, Takahiro Sumi, Daisuke Suzuki, Sean K. Terry, Paul J. Tristram, Aikaterini Vandorou, Hibiki Yama, (The MOA Collaboration)   +45 more
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Discerning Parallax Amplitude in Astrometric Microlensing

The Astronomical Journal, 2023
Gravitational microlensing is a powerful method for discovering isolated stellar-mass black holes (ISMBHs). These objects make long-duration microlensing events.
Sedighe Sajadian, Arya Mahmoudzadeh, Setareh Moein   +2 more
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