Gravitational microlensing - The effect of random motion of individual stars in the lensing galaxy

Kundić, Tomislav; Wambsganß, J.

doi:10.1086/172299

Cited by 51 publications

(76 citation statements)

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“…The A component w as active (Kundic et al 1995), and also, we have not found evidences of strong microlensing in the r R comparison (Oscoz et al 1997, Goicoechea et al 1998. A similar result (417 3 days; 2 con dence level) has been derived by Kundic et al (1997).…”

Section: Introductionsupporting

confidence: 86%

Gravitational Lenses and the Hubble Constant: Present and Future

Goicoechea

Mediavilla

Oscoz

et al. 1999

The Non-Sleeping Universe

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Section: Introductionsupporting

confidence: 86%

Gravitational Lenses and the Hubble Constant: Present and Future

Goicoechea

Mediavilla

Oscoz

et al. 1999

The Non-Sleeping Universe

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“…The direction is set to be the same in both patterns because the shear direction between images A and B is approximately the same (Witt & Mao 1994), and because we assume the motion of the source to be primarily due to the bulk motion of the lensing galaxy rather than to the individual motions of the stars. Kundic & Wambsganss (1993) and Wambsganss & Kundic (1995) show that the velocity dispersion of the stars can statistically be interpreted as a bulk velocity artificially increased by an efficiency factor a 1.3.…”

Section: Microlensing Simulations Fitting the Ogle Datamentioning

confidence: 99%

“…The effective transverse velocity is the result of the relative motion between the source, the lens and the observer (Kayser et al 1986), and is enhanced by a contribution from the velocity dispersion of the stars in the lensing galaxy (Kundic & Wambsganss 1993;Wambsganss & Kundic 1995). The problem is that we do not known the peculiar velocity of either the source, or the lens.…”

Section: Bayesian Analysismentioning

confidence: 99%

Microlensing variability in the gravitationally lensed quasar QSO 2237+0305 $\mathsf{\equiv}$ the Einstein Cross

Eigenbrod¹,

Courbin²,

Meylan³

et al. 2008

A&A

114

132

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We present the continuation of our long-term spectroscopic monitoring of the gravitationally lensed quasar QSO 2237+0305. We investigate the chromatic variations observed in the UV/optical continuum of both quasar images A and B, and compare them with numerical simulations to infer the energy profile of the quasar accretion disk. Our procedure combines the microlensing ray-shooting technique with Bayesian analysis, and derives probability distributions for the source sizes as a function of wavelength. We find that the effective caustic crossing timescale is 4.0 ± 1.0 months. Using a robust prior on the effective transverse velocity, we find that the source responsible for the UV/optical continuum has an energy profile well reproduced by a power-law R ∝ λ ζ with ζ = 1.2 ± 0.3, where R is the source size responsible for the emission at wavelength λ. This is the first accurate, model-independent determination of the energy profile of a quasar accretion disk on such small scales.

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“…The statistics of time delays has a rich history (e.g., Press et al 1992a,b;Pelt et al 1994Pelt et al , 1996, driven in part by the difficulty in obtaining a clean delay from Q0957+561 (the first lensed quasar discovered) until a sharp feature was finally seen in the light curves (Kundić et al 1995(Kundić et al , 1997. Most lens monitoring campaigns do not obtain regular sampling; dealing properly with unevenly sampled data is a crucial part of a successful light curve analysis.…”

Section: H 0 and The Practicalities Of Time Delay Measurementsmentioning

confidence: 99%

LSST Science Book, Version 2.0

Abell¹,

Burke²,

Hamuy³

et al. 2009

544

653

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Prepared by the LSST Science Collaborations, with contributions from the LSST Project. PrefaceMajor advances in our understanding of the Universe over the history of astronomy have often arisen from dramatic improvements in our ability to observe the sky to greater depth, in previously unexplored wavebands, with higher precision, or with improved spatial, spectral, or temporal resolution. Aided by rapid progress in information technology, current sky surveys are again changing the way we view and study the Universe, and the next-generation instruments, and the surveys that will be made with them, will maintain this revolutionary progress. Substantial progress in the important scientific problems of the next decade (determining the nature of dark energy and dark matter, studying the evolution of galaxies and the structure of our own Milky Way, opening up the time domain to discover faint variable objects, and mapping both the inner and outer Solar System) all require wide-field repeated deep imaging of the sky in optical bands.The wide-fast-deep science requirement leads to a single wide-field telescope and camera which can repeatedly survey the sky with deep short exposures. The Large Synoptic Survey Telescope (LSST), a dedicated telecope with an effective aperture of 6.7 meters and a field of view of 9.6 deg 2 , will make major contributions to all these scientific areas and more. It will carry out a survey of 20,000 deg 2 of the sky in six broad photometric bands, imaging each region of sky roughly 2000 times (1000 pairs of back-to-back 15-sec exposures) over a ten-year survey lifetime.The LSST project will deliver fully calibrated survey data to the United States scientific community and the public with no proprietary period. Near real-time alerts for transients will also be provided worldwide. A goal is worldwide participation in all data products. The survey will enable comprehensive exploration of the Solar System beyond the Kuiper Belt, new understanding of the structure of our Galaxy and that of the Local Group, and vast opportunities in cosmology and galaxy evolution using data for billions of distant galaxies. Since many of these science programs will involve the use of the world's largest non-proprietary database, a key goal is maximizing the usability of the data. Experience with previous surveys is that often their most exciting scientific results were unanticipated at the time that the survey was designed; we fully expect this to be the case for the LSST as well.The purpose of this Science Book is to examine and document in detail science goals, opportunities, and capabilities that will be provided by the LSST. The book addresses key questions that will be confronted by the LSST survey, and it poses new questions to be addressed by future study. It contains previously available material (including a number of White Papers submitted to the ASTRO2010 Decadal Survey) as well as new results from a year-long campaign of study and evaluation. This book does not attempt to be complete; there are many ...

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Gravitational microlensing - The effect of random motion of individual stars in the lensing galaxy

Cited by 51 publications

References 0 publications

Gravitational Lenses and the Hubble Constant: Present and Future

Gravitational Lenses and the Hubble Constant: Present and Future

Microlensing variability in the gravitationally lensed quasar QSO 2237+0305 $\mathsf{\equiv}$ the Einstein Cross

LSST Science Book, Version 2.0

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