LENSING EFFECTS ON THE PROTOGALAXY CANDIDATE CB58 AND THEIR IMPLICATIONS FOR THE COSMOLOGICAL CONSTANT

Authors
HAMANA T HATTORI M EBELING H HENRY JP FUTAMASE T SHIOYA Y
Citation
T. Hamana et al., LENSING EFFECTS ON THE PROTOGALAXY CANDIDATE CB58 AND THEIR IMPLICATIONS FOR THE COSMOLOGICAL CONSTANT, The Astrophysical journal, 484(2), 1997, pp. 574-580
Citations number
21
Categorie Soggetti
Astronomy & Astrophysics
Journal title
The Astrophysical journal → ACNP
ISSN journal
0004637X
Volume
484
Issue
2
Year of publication
1997
Part
1
Pages
574 - 580
Database
ISI
SICI code
0004-637X(1997)484:2<574:LEOTPC>2.0.ZU;2-4
Abstract
The amplification of the protogalaxy candidate cB58 due to gravitation al lensing by the foreground cluster of galaxies MS 1512.4+3647 is qua ntified based on recent ROSAT and ASCA X-ray observations. It is found that the amplification is at most 25 for any reasonable cosmological model with or without cosmological constant. It is also argued that th e system may be used to place new constraints on the value of the cosm ological constant. The gas mass fraction for this cluster is found to be about 0.2.