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Related papers: Diffractive Microlensing II: Substellar Disk and H…

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Diffraction is important when nearby substellar objects gravitationally lens distant stars. If the wavelength of the observation is comparable to the Schwarzschild radius of lensing object, diffraction leaves an observable imprint on the…

Instrumentation and Methods for Astrophysics · Physics 2013-02-26 Jeremy S. Heyl

Gravitational lensing is generally treated in the geometric optics limit; however, when the wavelength of the radiation approaches or exceeds the Schwarzschild radius of the lens, diffraction becomes important. Although the magnification…

Astrophysics of Galaxies · Physics 2015-05-18 Jeremy S. Heyl

We investigate the possibilities that pulsars act as the lens in gravitational microlensing events towards the galactic bulge or a spiral arm. Our estimation is based on expectant survey and observations of FAST (Five hundred meter Aperture…

High Energy Astrophysical Phenomena · Physics 2015-05-14 S. Dai , R. X. Xu , A. Esamdin

Microlensing and occultation are generally studied in the geometric optics limit. However, diffraction may be important when recently discovered Kuiper-Belt objects (KBOs) occult distant stars. In particular the effects of diffraction…

Earth and Planetary Astrophysics · Physics 2015-05-14 Jeeremy Heyl

The advent of new observational facilities in the last two decades has allowed the rapid discovery and high-resolution optical imaging of many strong lens systems from galaxy to cluster scales, as well as their spectroscopic follow-up.…

Astrophysics · Physics 2009-11-10 L. V. E. Koopmans , I. W. A. Browne , N. J. Jackson

When gravitational waves pass through the nuclear star clusters of galactic lenses, they may be microlensed by the stars. Such microlensing can cause potentially observable beating patterns on the waveform due to waveform superposition and…

High Energy Astrophysical Phenomena · Physics 2021-03-10 Mark H. Y. Cheung , Joseph Gais , Otto A. Hannuksela , Tjonnie G. F. Li

We study the wave optics features of gravitational microlensing by a binary lens composed of a planet and a parent star. In this system, the source star near the caustic line produces a pair of images in which they can play the role of…

Earth and Planetary Astrophysics · Physics 2015-06-05 Ahmad Mehrabi , Sohrab Rahvar

The detection of microlensing events from stars in the Large Magellanic Cloud and in the Galactic bulge raise important constraints on the distribution of dark matter and on galactic structure, although some events may be due to a new type…

Astrophysics · Physics 2020-11-25 David Valls-Gabaud

We present the results from recent VLA 8.5-GHz and WSRT 1.4 and 4.9-GHz monitoring campaigns of the CLASS gravitational lens B1600+434 and show how the observed variations argue strongly in favor of microlensing by MACHOs in the halo of a…

Astrophysics · Physics 2007-05-23 L. V. E. Koopmans , A. G. de Bruyn

Observations of caustic-crossing galaxies at redshift $0.7<z<1$ show a wealth of transient events. Most of them are believed to be microlensing events of highly magnified stars. Earlier work predicted such events should be common near the…

Microlensing observations have now become a useful tool in searching for non--luminous astrophysical compact objects (brown dwarfs, faint stars, neutron stars, black holes and even planets). Originally conceived for establishing whether the…

Astrophysics · Physics 2016-08-30 E. Roulet , S. Mollerach

Radio emission from stars can be used, e.g., to study ionized winds or stellar flares. The radio emission is faint and studies have been limited to few objects. The Square Kilometer Array (SKA) will bring a survey ability to the topic of…

Solar and Stellar Astrophysics · Physics 2021-04-27 Bin Yu , Albert Zijlstra , Biwei Jiang

Microlensing imprints by typical stellar mass lenses on gravitational waves are challenging to identify in the LIGO and Virgo frequency band because such effects are weak. However, stellar mass lenses are generally embedded in lens galaxies…

High Energy Astrophysical Phenomena · Physics 2023-12-01 Eungwang Seo , Otto A. Hannuksela , Tjonnie G. F. Li

High-resolution N-body simulations of dark matter halos indicate that the Milky Way contains numerous subhalos. When a dark matter subhalo passes in front of a star, the light from that star will be deflected by gravitational lensing,…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Adrienne L. Erickcek , Nicholas M. Law

The Square Kilometer Array (SKA) will enable studies of star formation in nearby galaxies with a level of detail never before possible outside of the Milky Way. Because the earliest stages of stellar evolution are often inaccessible at…

Astrophysics · Physics 2009-11-10 Kelsey E. Johnson

Strong gravitational lensing provides some of the deepest views of the Universe, enabling studies of high-redshift galaxies only possible with next-generation facilities without the lensing phenomenon. To date, 21 cm radio emission from…

Astrophysics of Galaxies · Physics 2015-08-06 R. P. Deane , D. Obreschkow , I. Heywood

If stars at the lower end of the main sequence are responsible for the microlensing events observed in the Galactic bulge, then light from the lensing star contributes to the observed brightness. The background and lensing stars generally…

Astrophysics · Physics 2009-10-22 Marc Kamionkowski

For microlensing case angular distances between images or typical astrometric shifts due to microlensing are about $10^{-5}-10^{-6} \mu as$. Such an angular resolution will be reached with the space space--ground interferometer Radioastron.…

Astrophysics · Physics 2007-05-23 Alexander F. Zakharov

We study the benefits of polarimetry observations of microlensing events to detect and characterize circumstellar disks around the microlensed stars located at the Galactic bulge. These disks which are unresolvable from their host stars…

Solar and Stellar Astrophysics · Physics 2016-05-11 Sedighe Sajadian , Sohrab Rahvar

We investigate the chance of detecting proto-planetary or debris disks in stars that induce microlensing events (lenses). The modification of the light curves shapes due to occultation and extinction by the disks as well as the additional…

Earth and Planetary Astrophysics · Physics 2015-05-13 M. Hundertmark , F. V. Hessman , S. Dreizler
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