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Related papers: Resolving Microlensing Events with Triggered VLBI

200 papers

We analyze three years (1998-2000) of OGLE observations of microlensing events to place limits on the abundance of planets with a planet-to-star mass ratio $q=10^{-3}$ at distances $\sim 1-4$AU from their host stars, i.e. `cool Jupiters'.…

Astrophysics · Physics 2009-11-07 Yiannis Tsapras , Keith Horne , Stephen Kane , Richard Carson

We investigate gravitational microlensing signals produced by a spatially extended object transiting in front of a finite-sized source star. The most interesting features arise for lens and source sizes comparable to the Einstein radius of…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-28 Djuna Croon , David McKeen , Nirmal Raj , Zihui Wang

Previous calculations of the rates and optical depths due to microlensing only considered resolved stars. However, if a faint unresolved star lens is close enough to a resolved star, the event will be seen by the microlensing experiments…

Astrophysics · Physics 2007-05-23 C. Alard

Microlensing events are usually selected among single-peaked non-repeating light curves in order to avoid confusion with variable stars. However, a microlensing event may exhibit a second microlensing brightening episode when the source…

Astrophysics · Physics 2009-11-13 J. Skowron , L. Wyrzykowski , S. Mao , M. Jaroszynski

Similarly to electromagnetic (EM) signals, gravitational lensing by intervening galaxies can also affect gravitational waves (GWs). In this paper, we estimate the strong-lensing rate of massive black hole mergers observed with LISA. Given…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-08 Juan Gutiérrez , Macarena Lagos

The VVV microlensing search has recently surveyed the region of the Galactic plane at b=0 within -10.00 < l < 10.44 deg. in the near-infrared (IR), discovering hundreds of microlensing events. In this paper we explore the microlensing…

Solar and Stellar Astrophysics · Physics 2020-10-14 Maria Gabriela Navarro , Dante Minniti , Rodrigo Contreras Ramos

The GAIA satellite can precisely measure the masses of nearby brown dwarfs and lower main sequence stars by the microlensing effect. The scientific yield is maximised if the microlensing event is also followed with ground-based telescopes…

Solar and Stellar Astrophysics · Physics 2014-09-08 N. W. Evans

At any instant, there are roughly 1000 ongoing microlensing events to sources brighter than 20th magnitude in the Milky Way Galaxy. Large-scale maps of the microlensing optical depth and the mean timescale are constructed for a number of…

Astrophysics · Physics 2009-11-07 N. W. Evans , V. Belokurov

The simplest interpretation of the microlensing events observed towards the Large Magellanic Clouds is that approximately half of the mass of the Milky Way halo is in the form of MAssive Compact Halo Objects with $M \sim 0.5 M_{\odot}$. It…

Astrophysics · Physics 2009-10-31 Anne M Green

Paczy\'nski (1986) suggested that ``dark" objects in the halo of our Galaxy could enhance the luminosity of foreground stars, acting as gravitational microlenses. Such events has been recently reported by different collaborations. We assume…

Astrophysics · Physics 2007-05-23 Sergio Campana

Gravitational microlensing is a unique probe of the stellar content in strong lens galaxies. Flux ratio anomalies from gravitationally lensed supernovae (glSNe), just like lensed quasars, can be used to constrain the stellar mass fractions…

Astrophysics of Galaxies · Physics 2025-04-01 Luke Weisenbach , Thomas Collett , Wolfgang Enzi , Lindsay Oldham , Ana Sainz de Murieta

In addition to constructing a Galactic matter mass function free from the bias induced by the hydrogen-burning limit, gravitational microlensing allows one to construct a mass function which is less affected by the problem of unresolved…

Astrophysics · Physics 2009-10-31 Kyongae Chang , Cheongho Han

January 2000 completes the first season of intensive, wide-field observations of microlensing and stellar variability in M31 by MEGA (Microlensing Exploration of the Galaxy and Andromeda) at the Isaac Newton 2.5m Telescope, the KPNO 4m, and…

Astrophysics · Physics 2009-09-25 A. Crotts , R. Uglesich , A. Gould , G. Gyuk , P. Sackett , K. Kuijken , W. Sutherland , L. Widrow

Microlensing detections of cool planets are important for the construction of an unbiased sample to estimate the frequency of planets beyond the snow line, which is where giant planets are thought to form according to the core accretion…

Earth and Planetary Astrophysics · Physics 2015-06-05 E. Bachelet , I. -G. Shin , C. Han , P. Fouqué , A. Gould , J. W. Menzies , J. -P. Beaulieu , D. P. Bennett , I. A. Bond , Subo Dong , D. Heyrovský , J. B. Marquette , J. Marshall , J. Skowron , R. A. Street , T. Sumi , A. Udalski , L. Abe , K. Agabi , M. D. Albrow , W. Allen , E. Bertin , M. Bos , D. M. Bramich , J. Chavez , G. W. Christie , A. A. Cole , N. Crouzet , S. Dieters , M. Dominik , J. Drummond , J. Greenhill , T. Guillot , C. B. Henderson , F. V. Hessman , K. Horne , M. Hundertmark , J. A. Johnson , U. G. Jørgensen , R. Kandori , C. Liebig , D. Mékarnia , J. McCormick , D. Moorhouse , T. Nagayama , D. Nataf , T. Natusch , S. Nishiyama , J. -P. Rivet , K. C. Sahu , Y. Shvartzvald , G. Thornley , A. R. Tomczak , Y. Tsapras , J. C. Yee , V. Batista , C. S. Bennett , S. Brillant , J. A. R. Caldwell , A. Cassan , E. Corrales , C. Coutures , D. Dominis Prester , J. Donatowicz , D. Kubas , R. Martin , A. Williams , M. Zub , L. Andrade de Almeida , D. L. DePoy , B. S. Gaudi , L. -W. Hung , F. Jablonski , S. Kaspi , N. Klein , C. -U. Lee , Y. Lee , J. -R. Koo , D. Maoz , J. A. Muñoz , R. W. Pogge , D. Polishook , A. Shporer , F. Abe , C. S. Botzler , P. Chote , M. Freeman , A. Fukui , K. Furusawa , P. Harris , Y. Itow , S. Kobara , C. H. Ling , K. Masuda , Y. Matsubara , N. Miyake , K. Ohmori , K. Ohnishi , N. J. Rattenbury , To. Saito , D. J. Sullivan , D. Suzuki , W. L. Sweatman , P. J. Tristram , K. Wada , P. C. M. Yock , M. K. Szymański , I. Soszyński , M. Kubiak , R. Poleski , K. Ulaczyk , G. Pietrzyński , Ł. Wyrzykowski , N. Kains , C. Snodgrass , I. A. Steele , K. A. Alsubai , V. Bozza , P. Browne , M. J. Burgdorf , S. Calchi Novati , P. Dodds , S. Dreizler , F. Finet , T. Gerner , S. Hardis , K. Harpsøe , T. C. Hinse , E. Kerins , L. Mancini , M. Mathiasen , M. T. Penny , S. Proft , S. Rahvar , D. Ricci , G. Scarpetta , S. Schäfer , F. Schönebeck , J. Southworth , J. Surdej , J. Wambsganss

Within 8 years, the current microlensing surveys of M31 will provide several hundred events affecting unresolved stars. They will thus allow a statistical study of the dark matter in M31's halo. The NGST will resolve these stars and…

Astrophysics · Physics 2007-05-23 S. Bensammar , A. -L. Melchior

We summarize the present status of VLBI experiments at 3 mm (86 GHz), 2 mm (129-150 GHz) and 1.3 mm (215-230 GHz). We present and discuss a new 3 mm VLBI map of M87 (Virgo A), which has a spatial resolution of only approx. 20 Schwarzschild…

We describe the discovery of the longest microlensing event ever observed, OGLE-1999-BUL-32, also independently identified by the MACHO collaboration as MACHO-99-BLG-22. This unique event has an Einstein radius crossing time of 641 days.…

Gravitational microlensing is a phenomenon that allows us to observe dark remnants of stellar evolution even if they no longer emit electromagnetic radiation. In particular, it can be useful to observe solitary neutron stars or stellar-mass…

We search for microlensing events in the zero-latitude area of the Galactic Bulge using the VVV Survey near-IR data. We have discovered a total sample of $N=630$ events within an area covering $20.68 deg^2$ between the years 2010 and 2015.…

With the increase in the number of observed gravitational wave (GW) signals, detecting strongly lensed GWs by galaxies has become a real possibility. Lens galaxies also contain microlenses (e.g., stars and black holes), introducing further…

Astrophysics of Galaxies · Physics 2022-10-05 Ashish Kumar Meena , Anuj Mishra , Anupreeta More , Sukanta Bose , Jasjeet Singh Bagla