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What is a Quasar?

  • Extremely luminous celestial objects thought to have been stars with high radio signal. The name quasar stands for "quasi-stellar radio source"

What do we know about them?

  • Likely to contain a supermassive black hole. Source of high redshift and appears as a point source in the sky as a result. Very distant objects, but are still visible due to its high luminosity. Size is roughly 10-10,000 times Schwarzschild radius of its black hole.

What is Gravitational Lensing?

  • Light from a source deflected as a result of passing through a strong gravitational field caused by a celestial object in it's path. Light from a gravitationally lensed source can be used to study various aspects of both the source of light and the object in between.

What are the open questions?

Comparing a typical quasar luminosity with the sun

Literature on Quasar Lensing

year - first author - title(url to paper) - data(survey)/theory

2012 - Inada, N. - The Sloan Digital Sky Survey Quasar Lens Search. V. Final Catalog from the Seventh Data Release - SDSS

1999 - Lehar, J. - HST Observations of 10 Two-Image Gravitational Lenses - HST

1996 - Schechter, P. L. - The Quadruple Gravitational Lens PG1115+080: Time Delays and Models - MDM Observatory, NOT, WIYN 3.5-m telescope

1992 - Blandford, R. D. - Cosmological Applications of Gravitational Lensing - Theory

1984 - Turner, E. L. - The Statistics of Gravitational Lenses: The Distribution of Image Angular Separations and Lens Redshifts - Princeton University Observatory

1980 - Young, P. - The Double Quasar Q0957 + 561 A, B: A Gravitational Lens Image Formed by a Galaxy at z=0.39 - 200in. Hale Telescope

1985 - Huchra, J. - 2237 + 0305; A New and Unusual Gravitational Lens - VLA, Whipple Observatory

Notes on "Gravitational Lenses"