منابع مشابه
The Quasar Distribution in a Static Universe
A crucial test of any cosmological model is the distribution of distant objects such as quasars. Because of well defined selection criteria quasars found by a ultraviolet excess (UVX) survey are ideal candidates for testing the model out to a redshift of z = 2.2. The static cosmology proposed by Crawford (1993) is used to analyse a recent quasar survey ( Boyle et al. 1990). It is shown that the...
متن کاملProbing the High-Redshift Universe with Quasar Elemental Abundances
The heavy elements near QSOs provide unique measures of the star formation and chemical evolution in young galactic nuclei or pre-galactic condensations. Studies of quasar abundances also naturally address a variety of questions regarding the physics of QSO environments, including the Baldwin Effect emphasized at this meeting. Here I review the status of quasar abundance work.
متن کاملQuasar Populations in a Cosmological Constant Dominated Flat Universe
Most physical properties derived for quasars, as single entities or as a population, depend upon the cosmology assumed. In this paper, we calculate the quasar luminosity function and some related quantities for a at universe dominated by a cosmological constant ((= 0:9; = 0:1) and compare them with those deduced for a at universe with zero cosmological constant ((= 0; = 1). We use the AAT quasa...
متن کاملcomparison of catalytic activity of heteropoly compounds in the synthesis of bis(indolyl)alkanes.
heteropoly acids (hpa) and their salts have advantages as catalysts which make them both economically and environmentally attractive, strong br?nsted acidity, exhibiting fast reversible multi-electron redox transformations under rather mild conditions, very high solubility in polar solvents, fairly high thermal stability in the solid states, and efficient oxidizing ability, so that they are imp...
15 صفحه اولThe properties of quasar hosts at the peak of the quasar activity
The properties of quasar hosts at the peak of the quasar activity Jari K. Kotilainen Tuorla Observatory, Department of Physics and Astronomy, University of Turku, Väisäläntie 20, FI–21500 Piikkiö, Finland [email protected] Renato Falomo INAF – Osservatorio Astronomico di Padova, Vicolo dell’Osservatorio 5, I-35122 Padova, Italy [email protected] Roberto Decarli and Aldo Treves Università d...
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ژورنال
عنوان ژورنال: Proceedings of the International Astronomical Union
سال: 2012
ISSN: 1743-9213,1743-9221
DOI: 10.1017/s1743921313005012