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Astrophysical Applications of Gravitational Micro-Lensing

Published online by Cambridge University Press:  19 July 2016

R. Kayser ,
S. Refsdal ,
R. Stabell  and
B. Grieger
R. Kayser
Affiliation:
*Hamburger Sternwarte Gojenbergsweg 112 D-2050 Hamburg 80 F.R. Germany
S. Refsdal
Affiliation:
*Hamburger Sternwarte Gojenbergsweg 112 D-2050 Hamburg 80 F.R. Germany
R. Stabell
Affiliation:
+Institute of Theoretical Astrophysics University of Oslo P.B. 1029 Blindern Oslo 3 Norway
B. Grieger
Affiliation:
*Hamburger Sternwarte Gojenbergsweg 112 D-2050 Hamburg 80 F.R. Germany

Abstract

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Gravitational micro-lensing due to stars in the deflecting galaxy influences the brightness and the spectra of the macro-images. Thus differences in the spectra of different macro-images are not automatically an argument against gravitational lensing. Furthermore changes in the spectra due to micro-lensing may give informations on the quasar structure. From high amplification events the brightness profile of the source may be obtained. The time scale of the high amplification event is proportional to the source radius and inverse proportional to the transversal velocity. Due to the large brightness gradient by a high amplification event, a “parallax-effect” occurs, from which the transversal velocity may be obtained, and thereby the source radius (R=Δ t · VT). We roughly estimate 0.3 high amplication events per year for all gravitationally lensed quasars. Frequent monitoring should be carried out in order to predict high amplification events as early as possible.

Type
Chapter XIII: Gravitational Lenses
Information
Symposium - International Astronomical Union , Volume 124: Observational Cosmology , 1987 , pp. 767 - 770
Copyright
Copyright © Reidel 1987 

References

1. Chang, K., Refsdal, S.: 1979, Nature 282, 561.CrossRefGoogle Scholar
2. Kayser, R., Refsdal, S., Stabell, R.: 1986, Astron. Astrophys. 166, 36.Google Scholar
3. Grieger, B., Kayser, R., Refsdal, S.: 1987, in preparation.Google Scholar
4. Chang, K., Refsdal, S.: 1984, Astron. Astrophys. 132, 168.Google Scholar
5. Grieger, B., Kayser, R., Refsdal, S.: 1986, Nature, in press.Google Scholar
6. Foy, R., Bonneau, D., Blazit, A.: 1985, Astron. Astrophys. 149, L13.Google Scholar
7. Christian, C., Crabtree, D., Wadell, P.: 1986, IAU Circular No. 4182.Google Scholar