Results 311 to 320 of about 247,102 (346)

The Luminosity Functions of Galaxies

Annual Review of Astronomy and Astrophysics, 1988
La fonction de luminosite est etudiee pour divers types de galaxies et divers environnements physiques. Le probleme de l'utilisation d'une fonction de luminosite generale est souleve et discute en fonction de la densite des ...
Bruno Binggeli, Allan Sandage, G. A. Tammann   +2 more
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Class I Luminosity Functions

1994
Combining space- and ground-based IR and mm observations an unbiased and flux limited survey for Class I sources [age O(105 yr)] in the star-forming Vela-GMCs has been performed (Liseau et al 1992; Lorenzetti, Liseau, & Spinoglio 1993). These relatively nearby Giant Molecular Clouds are situated near the plane of the Galaxy, which offers the ...
René Liseau, Dario Lorenzetti, Luigi Spinoglio   +2 more
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The stellar luminosity function

2000
The stellar luminosity function, Φ(M) — the number of stars per unit absolute magnitude per unit volume is one of the fundamental quantities required for understanding star formation and investigating the structure of our Galaxy. In recent years, most emphasis has been placed on determining the shape of Φ(M) at faint magnitude — and hence the mass ...
I. Neill Reid, Suzanne L. Hawley
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The Morphological Luminosity Function

1988
We obtain the morphological luminosity function for galaxies assuming that they form at high density regions of a filtered Gaussian random field. We compare our results with some observations of the LF for E and E+SO galaxies. Using scale-free spectra, we obtain bell-shaped curves that follow the observations.
J. L. Sanz, E. Martínez-González
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Evolution of Galaxy Luminosity Function and Luminosity Function by Density Environment at 0.03

2006
Using galaxy sample observed by the BATC large-field multi-color sky survey and galaxy data of SDSS in the overlapped fields, we study the dependence of the restframe $r$-band galaxy luminosity function on redshift and on large-scale environment. The large-scale environment is defined by isodensity contour with density contrast / . The data set is
Xia, Lifang, Zhou, Xu, Yang, Yanbin, Ma, Jun, Jiang, Zhaoji   +4 more
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The Quasar Luminosity Function

1993
Recent work on the quasar luminosity function at radio, optical and X-ray wavelengths is reviewed. It is demonstrated that the evolution of the quasar luminosity function in all three regimes is marked by a strong and approximately similar power-law increase in luminosity, L ∝ (1 + z) 3±0.5, between the present epoch and z ≈ 2.
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Multi-Wavelength Luminosity Functions of Galaxies

AIP Conference Proceedings, 2003
Multivariate or multi‐wavelength luminosity functions will reveal the interplay between star formation, chemical evolution, and absorption and re‐emission of dust within evolving galaxy populations. By using principal component analysis to reduce the dimensionality of the problem, I optimally extract the relevant photometric information from large ...
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The radio luminosity function and the luminosity diameter function of extragalactic radio sources

Astronomische Nachrichten, 1971
AbstractOn the basis of a radio index‐surface brightness diagram recently published, the luminosity function and the luminosity diameter function are obtained. The uncertainties due to the incompleteness of the sample are of the same order as the statistical uncertainties.
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Luminosity Functions and the Mass Function

1995
The determination of the Mass Function (MF) at the bottom of the Main Sequence is subject to severe uncertainties, due both to the very low intrinsic luminosity of these stars and to their rapidly varying Mass-Luminosity (ML) relation. A potentially very important field of exploration, although its present results are still to be correctly examined and
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The Cluster Galaxy Luminosity Function

Astrophysics and Space Science, 1999
Our project to assess the LF of galaxies in clusters is giving the first results. A universal LF shape cannot be supported and the evolution has to be taken into account to explain differences. The blue galaxy distribution is also investigated.
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