Results 81 to 90 of about 10,480 (204)

Microlensing of Broad Absorption Line Quasars: Polarization Variability

, 1999
Roughly 10% of all quasars exhibit Broad Absorption Line (BAL) features which appear to arise in material outflowing at high velocity from the active galactic nucleus (AGN).
Angonin M.-C., Antonucci R. R., Chang K., Chavushyan V. H., Geraint F. Lewis, Hutsemekers D., Kayser R., Kneib J.-P., Kneib J.-P., Kunegunda E. Belle, Lewis G. F., Lewis G. F., Lewis G. F., Meylan G., Schneider P., Schramm T., Wisotzki L., Witt H.-J., Yonehara A.   +18 more
core   +1 more source

Accretion Disk Size and Updated Time-delay Measurements in the Gravitationally Lensed Quasar SDSS J165043.44+425149.3

The Astrophysical Journal
We analyze variability in 15-season optical lightcurves from the doubly imaged lensed quasar SDSS J165043.44+425149.3 (SDSS1650), comprising five seasons of monitoring data from the Maidanak Observatory (277 nights in total, including the two seasons of ...
A. B. Rivera, C. W. Morgan, S. M. Florence, K. Kniezewski, M. Millon, F. Courbin, S. E. Dahm, F. J. Vrba, T. M. Tilleman, M. A. Cornachione, I. M. Asfandiyarov, S. A. Ehgamberdiev, O. A. Burkhonov   +12 more
doaj   +1 more source

Candidate Microlensing Brown Dwarfs in Binary Lens Systems from the 2023–2025 Observing Seasons

The Astronomical Journal
We present detailed light-curve analyses of 10 binary-lens microlensing events observed during the 2023–2025 seasons and selected as candidates for hosting brown dwarf companions.
Cheongho Han, Andrzej Udalski, Ian A. Bond, Chung-Uk Lee, (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, (KMTNet Collaboration), Przemek Mróz, 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 Collaboration), Fumio Abe, David P. Bennett, Aparna Bhattacharya, Ryusei Hamada, Yuki Hirao, Asahi Idei, Stela Ishitani Silva, Shuma Makida, Shota Miyazaki, Yasushi Muraki, Tutumi Nagai, Togo Nagano, Seiya Nakayama, Mayu Nishio, Kansuke Nunota, Ryo Ogawa, Ryunosuke Oishi, Yui Okumoto, Greg Olmschenk, Clément Ranc, Nicholas J. Rattenbury, Yuki Satoh, Takahiro Sumi, Daisuke Suzuki, Takuto Tamaoki, Sean K. Terry, Paul J. Tristram, Aikaterini Vandorou, Hibiki Yama, (The MOA/PRIME Collaboration)   +68 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

Gravitational Microlensing, the Distance Scale, and the Ages [PDF]

Symposium - International Astronomical Union, 1996
A high optical depth to gravitational microlensing towards the galactic bulge is consistent with current models of the galactic bar. The low optical depth towards the LMC can probably be accounted for by the ordinary stars in our galaxy and in the LMC itself. No conclusive evidence is available yet for the presence or absence of a large number of brown
openaire   +3 more sources

Estimating Microlensing Parameters from Observables and Stellar Isochrones with pyLIMASS

The Astronomical Journal
We present pyLIMASS, a novel algorithm for estimating the physical properties of the lensing system in microlensing events. The main idea of pyLIMASS is to combine all available information regarding the microlensing event, defined as observables , and ...
E. Bachelet, M. Hundertmark, S. Calchi Novati   +2 more
doaj   +1 more source

Planetary Microlensing: Present Status and Long-term Goals

, 1999
Massive gravitational microlensing programs were begun about a decade ago as a means to search for compact baryonic dark matter in the Galaxy, but before the first events were detected the technique was also proposed as a means of detecting extra-solar ...
Sackett, Penny D.
core   +2 more sources

Gravitational lens system SDSS J1339+1310: microlensing factory and time delay

, 2016
We spectroscopically re-observed the gravitational lens system SDSS J1339+1310 using OSIRIS on the GTC. We also monitored the $r$-band variability of the two quasar images (A and B) with the LT over 143 epochs in the period 2009$-$2016. These new data in
Goicoechea, Luis J., Shalyapin, Vyacheslav N.   +1 more
core   +1 more source

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
doaj   +1 more source

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
doaj   +1 more source