Results 81 to 90 of about 369 (182)

Detecting Dark Objects with Plasma Microlensing by Their Gravitational Wakes

The Astrophysical Journal
A moving mass makes a gravitational wake in the partially ionized interstellar medium, which acts as a lens for radio-frequency light. Consequently, plasma microlensing could complement gravitational microlensing in the search for invisible massive ...
M. Sten Delos
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Four-body Gravitational Microlensing Events Involving Both a Binary Lens and a Binary Source

The Astrophysical Journal
We present detailed analyses of three anomalous microlensing events—KMT-2021-BLG-0209, KMT-2021-BLG-0901, and OGLE-2025-BLG-0356—identified from a systematic reexamination of KMTNet light curves for which previous modeling attempts failed or left ...
Cheongho Han, Chung-Uk Lee, Andrzej Udalski, (Leading Authors), Michael D. Albrow, Sun-Ju Chung, Andrew Gould, Youn Kil Jung, Kyu-Ha Hwang, Yoon-Hyun Ryu, Yossi Shvartzvald, In-Gu Shin, Jennifer C. Yee, Weicheng Zang, Hongjing Yang, Doeon Kim, Dong-Jin Kim, Seung-Lee Kim, Dong-Joo Lee, Sang-Mok Cha, Yongseok Lee, Byeong-Gon Park, Richard W. Pogge, Przemek Mróz, (KMTNet Collaboration), Michał K. Szymański, Jan Skowron, Radosław Poleski, Igor Soszyński, Paweł Pietrukowicz, Szymon Kozłowski, Krzysztof A. Rybicki, Patryk Iwanek, Krzysztof Ulaczyk, Marcin Wrona, Mariusz Gromadzki, Mateusz J. Mróz, (The OGLE Team)   +37 more
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GRAVITATIONAL MICROLENSING AND EXTENDED SOURCE MODELS

Odessa Astronomical Publications, 2014
We perform statistical simulations of light curves of extended microlensed sources having different brightness distribution in the source plane. We generated a set of realizations of lensing point mass system that takes into account an external shear ...
V. M. Sliusar, V. I. Zhdanov
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Gravitational microlensing research

, 1997
One of the most important problems in astrophysics concerns the nature of the dark matter in galactic halos, whose presence is implied mainly by the observed flat rotation curves in spiral galaxies. In the framework of a baryonic scenario the most plausible candidates are brown dwarfs, M-dwarfs or white dwarfs and cold molecular clouds (mainly of $H_2$)
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Introduction to Gravitational Microlensing

, 2008
The basic concepts of gravitational microlensing are introduced. We start with the lens equation, and then derive the image positions and magnifications. The statistical quantities of optical depth and event rate are then described. We finish with a summary and a list of challenges and open questions. A problem set is given for students to practice.
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LensNet: Enhancing Real-time Microlensing Event Discovery with Recurrent Neural Networks in the Korea Microlensing Telescope Network

The Astronomical Journal
Traditional microlensing event vetting methods require highly trained human experts, and the process is both complex and time consuming. This reliance on manual inspection often leads to inefficiencies and constrains the ability to scale for widespread ...
Javier Viaña, Kyu-Ha Hwang, Zoë de Beurs, Jennifer C. Yee, Andrew Vanderburg, Michael D. Albrow, Sun-Ju Chung, Andrew Gould, Cheongho Han, Youn Kil Jung, Yoon-Hyun Ryu, In-Gu Shin, Yossi Shvartzvald, Hongjing Yang, 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   +22 more
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Gravitational Microlensing by Rotating Stars

, 2005
12 pages, 4 figures, AAS ...
Rahbari, Habib Ebrahimnejad, Nouri-Zonoz, Mohammad, Rahvar, Sohrab   +2 more
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microJAX: A Differentiable Framework for Microlensing Modeling with GPU-accelerated Image-centered Ray Shooting

The Astrophysical Journal
We introduce microJAX , the first fully differentiable implementation of the image-centered ray shooting algorithm for gravitational microlensing. Built on JAX and its XLA just-in-time compiler, microJAX exploits GPU parallelism while providing exact ...
Shota Miyazaki, Hajime Kawahara
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Microlensing Optical Depth, Event Rate, and Limits on Compact Objects in Dark Matter Based on 20 Yr of OGLE Observations of the Small Magellanic Cloud

The Astrophysical Journal Supplement Series
Some previous studies have suggested that massive and intermediate-mass primordial black holes (PBHs) could comprise a substantial fraction of dark matter in the Universe.
Przemek Mróz, Andrzej Udalski, Michał K. Szymański, Igor Soszyński, Paweł Pietrukowicz, Szymon Kozłowski, Radosław Poleski, Jan Skowron, Dorota Skowron, Krzysztof Ulaczyk, Mariusz Gromadzki, Krzysztof Rybicki, Patryk Iwanek, Marcin Wrona, Milena Ratajczak   +14 more
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Entropy of the Universe and Hierarchical Dark Matter. [PDF]

Entropy (Basel), 2022
Frampton PH.
europepmc   +1 more source