2003年1月
Images for an isothermal ellipsoidal gravitational lens from a single real algebraic equation
ASTRONOMY & ASTROPHYSICS
- ,
- ,
- 巻
- 397
- 号
- 3
- 開始ページ
- 825
- 終了ページ
- 829
- 記述言語
- 英語
- 掲載種別
- DOI
- 10.1051/0004-6361:20021599
- 出版者・発行元
- E D P SCIENCES
We present explicit expressions for the lens equation for a cored isothermal ellipsoidal gravitational lens as a single real sixth-order algebraic equation in two approaches; 2-dimensional Cartesian coordinates and 3-dimensional polar ones. We find a condition for physical solutions which correspond to at most five images. For a singular isothermal ellipsoid, the sixth-order equation is reduced to fourth-order one for which analytic solutions are well-known. Furthermore, we derive analytic criteria for determining the number of images for the singular lens, which give us simple expressions for the caustics and critical curves. The present formulation offers a useful way for studying galaxy lenses frequently modeled as isothermal ellipsoids.
- リンク情報
- ID情報
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- DOI : 10.1051/0004-6361:20021599
- ISSN : 0004-6361
- Web of Science ID : WOS:000180249800010