Sign on

SAO/NASA ADS Astronomy Abstract Service


· Find Similar Abstracts (with default settings below)
· Full Refereed Journal Article (PDF/Postscript)
· Full Refereed Scanned Article (GIF)
· References in the article
· Citations to the Article (53) (Citation History)
· Refereed Citations to the Article
· SIMBAD Objects (2)
· NED Objects (1)
· Also-Read Articles (Reads History)
·
· Translate This Page
Title:
Interpretation of microlensing events in Q2237 + 0305
Authors:
Witt, Hans J.; Mao, Shude
Affiliation:
AA(Princeton University Observatory, Peyton Hall, Princeton, NJ 08544), AB(MS 51 Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138)
Publication:
The Astrophysical Journal, Part 1 (ISSN 0004-637X), vol. 429, no. 1, p. 66-76 (ApJ Homepage)
Publication Date:
07/1994
Category:
Astrophysics
Origin:
STI
NASA/STI Keywords:
Alignment, Gravitational Lenses, Magnification, Quasars, Displacement, Galactic Halos, Galactic Structure, Image Analysis, Shear Properties
DOI:
10.1086/174302
Bibliographic Code:
1994ApJ...429...66W

Abstract

We point out the uncertainties in the potential models of the foreground galaxy in the gravitational lens Q2237 + 0305. The surface densities and external shears are uncertain by a factor of appproximately less than 2. Very long light curves are calculated for different models using the method developed by Witt (1993) and Lewis et al. (1993). We find that the probability of images being in a quiescent state depends strongly on the potential models and the direction of the source motion relative to the alignment of the (gravitational lens) shear term of the macroimages. For example, the probabilities of finding variations smaller than 0.1 mag and for a period of longer than 0.5 Einstein radii (approximately equals 3-5 yr) in image C and D are approximately 30%. This offers an explanation of why image C and D showed relatively small variations. The quiescent images are more likely to be demagnified, consistent with the observations. Further, the higher the magnification of the macroimages, the weaker are the microlensing events. In addition, we conclude that a simple Gaussian profile has some difficulties in explaining the asymmetric shape and the small amplitude of the observed high-magnification events if they are typical. Source models in which the emission is produced by a brightt compact core and a more extended halo can occur better explain the observed double peak events. More data are needed to clearly distinguish different galaxy potential models.

Printing Options

Print whole paper
Print Page(s) through

Return 600 dpi PDF to Acrobat/Browser. Different resolutions (200 or 600 dpi), formats (Postscript, PDF, etc), page sizes (US Letter, European A4, etc), and compression (gzip,compress,none) can be set through the Printing Preferences



More Article Retrieval Options

HELP for Article Retrieval


Bibtex entry for this abstract   Preferred format for this abstract (see Preferences)


Find Similar Abstracts:

Use: Authors
Title
Keywords (in text query field)
Abstract Text
Return: Query Results Return    items starting with number
Query Form
Database: Astronomy
Physics
arXiv e-prints