Results 71 to 80 of about 351 (182)

Two Low Mass-ratio Microlensing Planets and Two Types of Central-resonant Degeneracy

The Astronomical Journal
We present observations and analysis of two low planet/host mass-ratio ( q ) microlensing planets discovered in high-magnification events. KMT-2025-BLG-0811Lb has q  ∼ 4.5 × 10 ^−5 , and a Bayesian analysis favors a super-Earth/mini-Neptune orbiting an M-
Yuchen Tang, Weicheng Zang, Yoon-Hyun Ryu, Andrzej Udalski, Hongjing Yang, (Leading Authors), Michael D. Albrow, Sun-Ju Chung, Andrew Gould, Cheongho Han, Kyu-Ha Hwang, Youn Kil Jung, In-Gu Shin, Yossi Shvartzvald, Jennifer C. Yee, Dong-Jin Kim, Chung-Uk Lee, Byeong-Gon Park, (The KMTNet Collaboration), Leandro de Almeida, Yunyi Tang, Zhixing Li, Jiyuan Zhang, Hongyu Li, Shude Mao, Qiyue Qian, Dan Maoz, Christian Elias Borges, Fabrício Santos Kalaki, Altair Ramos Gomes-Júnior, Wei Zhu, (The MAP & 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)   +45 more
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Gravitational microlensing—A report on the MACHO project [PDF]

Reviews of Modern Physics, 1999
There is abundant evidence that the mass of the Universe is dominated by dark matter of unknown form. The MACHO project is one of several teams searching for the dark matter around our Galaxy in the form of Massive Compact Halo Objects (MACHOs).
openaire   +2 more sources

Quasar Microlensing Statistics and Flux-ratio Anomalies in Lens Models

The Astronomical Journal
Precise lens modeling is a critical step in time delay studies of multiply imaged quasars, which are key for measuring some important cosmological parameters (especially H _0 ).
E. Mediavilla, J. Jiménez-Vicente, V. Motta   +2 more
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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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Fractal Algorithm for Multiple-lens Analyses

The Astrophysical Journal
A microlensing exoplanet search is a unique method for finding planets orbiting distant stars. However, in the past, the method used to analyze microlensing data could not deal with complex lens systems. The number of lenses was limited to three or less.
F. Abe
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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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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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Influence of Microlensing on Spectral Anomalies of the Lensed Objects

Open Astronomy, 2011
Here we consider the influence of microlensing on the spectrum of a lensed object with the angular size 5 μas accepting that the composite emission of this object originates from three different regions arranged around its center.
Simić S., Popović L. Č., Jovanović P.   +2 more
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Casting Light on Degeneracies: A Comprehensive Study of Lightcurve Variations in Microlensing Events OGLE-2017-BLG-0103 and OGLE-2017-BLG-0192

The Astronomical Journal
This study investigates orbital parallax in gravitational microlensing events, focusing on OGLE-2017-BLG-0103 and OGLE-2017-BLG-0192. For events with timescales ≤60 days, a Jerk-Parallax degeneracy arises due to high Jerk velocity ( $\tilde{{v}_{j ...
Sarang Shah
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Parallax Effect in Microlensing Events Due to Free-floating Planets

The Astronomical Journal
One of the most important applications of microlensing observations is the detection of free-floating planets (FFPs). The timescale of microlensing due to FFPs ( t _E ) is short (a few days). Discerning the annual parallax effect in observations of these
Parisa Sangtarash, Sedighe Sajadian
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