Results 61 to 70 of about 168,724 (208)

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
doaj   +1 more source

Dark Matter Halos from the Inside Out

Advances in Astronomy, Volume 2011, Issue 1, 2011., 2011
The balance of evidence indicates that individual galaxies and groups or clusters of galaxies are embedded in enormous distributions of cold, weakly interacting dark matter. These dark matter “halos” provide the scaffolding for all luminous structures in the universe, and their properties comprise an essential part of the current cosmological model.
James E. Taylor, Rob Ivison
wiley   +1 more source

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
doaj   +1 more source

Dark Matter: A Primer

Advances in Astronomy, Volume 2011, Issue 1, 2011., 2011
Dark matter is one of the greatest unsolved mysteries in cosmology at the present time. About 80% of the Universe′s gravitating matter is nonluminous, and its nature and distribution are for the most part unknown. In this paper, we will outline the history, astrophysical evidence, candidates, and detection methods of dark matter, with the goal to give ...
Katherine Garrett, Gintaras Dūda, David Merritt   +2 more
wiley   +1 more source

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
doaj   +1 more source

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
doaj   +1 more source

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
doaj   +1 more source

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
doaj   +1 more source

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
doaj   +1 more source

Gravitational Microlensing

, 2006
This review forms the microlensing part of the 33rd Saas-Fee Advanced Course "Gravitational Lensing: Strong, Weak & Micro'', which was held in April 2003 in Les Diablerets. It contains an introduction to the lensing effects of single and binary stars and it summarizes the state-of-the-art of microlensing observations and prospects at the time of ...
openaire   +2 more sources