Space Distribution and Luminosity Functions of Quasi-Stellar Radio Sources
About: This article is published in The Astrophysical Journal.The article was published on 1968-01-01. It has received 1440 citations till now. The article focuses on the topics: Luminosity function (astronomy) & Luminosity.
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Max Planck Society1, Johns Hopkins University2, Centre national de la recherche scientifique3, Centra4, University of Chicago5, New York University6, New Mexico State University7, Yale University8, Eötvös Loránd University9, University of Tokyo10, Princeton University11, United States Department of the Navy12, Carnegie Mellon University13, Ohio State University14
TL;DR: In this paper, the authors used Monte Carlo realizations of different star formation histories, including starbursts of varying strength and a range of metallicities, to constrain the mean stellar ages of galaxies and the fractional stellar mass formed in bursts over the past few Gyr.
Abstract: We develop a new method to constrain the star formation histories, dust attenuation and stellar masses of galaxies. It is based on two stellar absorption-line indices, the 4000-A break strength and the Balmer absorption-line index Hδ A . Together, these indices allow us to constrain the mean stellar ages of galaxies and the fractional stellar mass formed in bursts over the past few Gyr. A comparison with broad-band photometry then yields estimates of dust attenuation and of stellar mass. We generate a large library of Monte Carlo realizations of different star formation histories, including starbursts of varying strength and a range of metallicities. We use this library to generate median likelihood estimates of burst mass fractions, dust attenuation strengths, stellar masses and stellar mass-to-light ratios for a sample of 122 808 galaxies drawn from the Sloan Digital Sky Survey. The typical 95 per cent confidence range in our estimated stellar masses is ′40 per cent. We study how the stellar mass-to-light ratios of galaxies vary as a function of absolute magnitude, concentration index and photometric passband and how dust attenuation varies as a function of absolute magnitude and 4000-A break strength. We also calculate how the total stellar mass of the present Universe is distributed over galaxies as a function of their mass, size, concentration, colour, burst mass fraction and surface mass density. We find that most of the stellar mass in the local Universe resides in galaxies that have, to within a factor of approximately 2, stellar masses ∼5 x 10 1 0 M O ., half-light radii ∼3 kpc and half-light surface mass densities ∼10 9 M O .kpc - 2 . The distribution of D n (4000) is strongly bimodal, showing a clear division between galaxies dominated by old stellar populations and galaxies with more recent star formation.
2,407 citations
Cites methods from "Space Distribution and Luminosity F..."
...In this paper we use the simplest available method for correcting for selection effects, the V max correction method (Schmidt 1968)....
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TL;DR: The New York University Value-Added Galaxy Catalog (NYU-VAGC) as mentioned in this paper is a catalog of local galaxies (mostly below z ≈ 0.3) based on a set of publicly released surveys matched to the SDSS Data Release 2.
Abstract: Here we present the New York University Value-Added Galaxy Catalog (NYU-VAGC), a catalog of local galaxies (mostly below z ≈ 0.3) based on a set of publicly released surveys matched to the Sloan Digital Sky Survey (SDSS) Data Release 2. The photometric catalog consists of 693,319 galaxies, QSOs, and stars; 343,568 of these have redshift determinations, mostly from the SDSS. Excluding areas masked by bright stars, the photometric sample covers 3514 deg2, and the spectroscopic sample covers 2627 deg2 (with about 85% completeness). Earlier, proprietary versions of this catalog have formed the basis of many SDSS investigations of the power spectrum, correlation function, and luminosity function of galaxies. Future releases will follow future public releases of the SDSS. The catalog includes matches to the Two Micron All Sky Survey Point Source Catalog and Extended Source Catalog, the IRAS Point Source Catalog Redshift Survey, the Two-Degree Field Galaxy Redshift Survey, the Third Reference Catalogue of Bright Galaxies, and the Faint Images of the Radio Sky at Twenty cm survey. We calculate and compile derived quantities from the images and spectra of the galaxies in the catalogs (for example, K-corrections and structural parameters for the galaxies). The SDSS catalog presented here is photometrically calibrated in a more consistent way than that distributed by the SDSS Data Release 2 Archive Servers and is thus more appropriate for large-scale structure statistics, reducing systematic calibration errors across the sky from ~2% to ~1%. We include an explicit description of the geometry of the catalog, including all imaging and targeting information as a function of sky position. Finally, we have performed eyeball quality checks on a large number of objects in the catalog in order to flag errors (such as errors in deblending). This catalog is complementary to the SDSS Archive Servers in that NYU-VAGC's calibration, geometric description, and conveniently small size are specifically designed for studying galaxy properties and large-scale structure statistics using the SDSS spectroscopic catalog.
1,300 citations
Cites methods from "Space Distribution and Luminosity F..."
...…of their properties, it is necessary to compute the numberdensity contribution 1/Vmax for each galaxy, where Vmax is the volume covered by the survey in which this galaxy could have been observed, accounting for the flux, redshift limits, and completeness as a function of angle (Schmidt 1968)....
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01 Jan 1981TL;DR: In this article, the authors introduce high energy astrophysics in the context of galaxies and the origin of cosmic rays in our galaxy, as well as the acceleration of high energy particles in magnetic fields.
Abstract: Part I. Astronomical Background: 1. High energy astrophysics - an introduction 2. The stars and stellar evolution 3. The galaxies 4. Clusters of galaxies Part II. Physical Processes: 5. Ionisation losses 6. Radiation of accelerated charged particles and bremsstrahlung of electrons 7. The dynamics of charged particles in magnetic fields 8. Synchrotron radiation 9. Interactions of high energy photons 10. Nuclear interactions 11. Aspects of plasma physics and magnetohydrodynamics Part III. High Energy Astrophysics in our Galaxy: 12. Interstellar gas and magnetic fields 13. Dead stars 14. Accretion power in astrophysics 15. Cosmic rays 16. The origin of cosmic rays in our galaxy 17. The acceleration of high energy particles Part IV. Extragalactic High Energy Astrophysics: 18. Active galaxies 19. Black holes in the nuclei of galaxies 20. The vicinity of the black hole 21. Extragalactic radio sources 22. Compact extragalactic sources and superluminal motions 23. Cosmological aspects of high energy astrophysics Appendix References Index.
1,280 citations
University of California, Santa Cruz1, University of Arizona2, University of Oxford3, Lawrence Berkeley National Laboratory4, Seoul National University5, University of California, Berkeley6, Princeton University7, University of Texas at Austin8, Max Planck Society9, University of Chicago10, National Taiwan University11, University of Florida12, University of Virginia13, Herzberg Institute of Astrophysics14, Johns Hopkins University15, New Mexico State University16
TL;DR: The DEEP2 and COMBO-17 surveys are compared to study luminosity functions of red and blue galaxies to z ~ 1, and the results imply that the number and total stellar mass of blue galaxies have been substantially constant since z = 1, whereas those of red galaxies (near L*) have been significantly rising as mentioned in this paper.
Abstract: The DEEP2 and COMBO-17 surveys are compared to study luminosity functions of red and blue galaxies to z ~ 1. The two surveys have different methods and sensitivities, but nevertheless results agree. After z ~ 1, M has dimmed by 1.2-1.3 mag for all colors of galaxies, * for blue galaxies has hardly changed, and * for red galaxies has at least doubled (our formal value is ~0.5 dex). Luminosity density jB has fallen by 0.6 dex for blue galaxies but has remained nearly constant for red galaxies. These results imply that the number and total stellar mass of blue galaxies have been substantially constant since z ~ 1, whereas those of red galaxies (near L*) have been significantly rising. To explain the new red galaxies, a ``mixed'' scenario is proposed in which star formation in blue cloud galaxies is quenched, causing them to migrate to the red sequence, where they merge further in a small number of stellar mergers. This mixed scenario matches the local boxy-disky transition for nearby ellipticals, as well as red sequence stellar population scaling laws such as the color-magnitude and Mg-? relations (which are explained as fossil relics from blue progenitors). Blue galaxies enter the red sequence via different quenching modes, each of which peaks at a different characteristic mass and time. The red sequence therefore likely builds up in different ways at different times and masses, and the concept of a single process that is ``downsizing'' (or upsizing) probably does not apply. Our claim in this paper of a rise in the number of red galaxies applies to galaxies near L*. Accurate counts of brighter galaxies on the steep part of the Schechter function require more accurate photometry than is currently available.
1,193 citations
TL;DR: In this article, the authors used a complete sample of about 140,000 galaxies from the Sloan Digital Sky Survey (SDSS) to study the size distribution of galaxies and its dependence on their luminosity, stellar mass, and morphological type.
Abstract: We use a complete sample of about 140,000 galaxies from the Sloan Digital Sky Survey (SDSS) to study the size distribution of galaxies and its dependence on their luminosity, stellar mass, and morphological type. The large SDSS database provides statistics of unprecedented accuracy. For each type of galaxy, the size distribution at given luminosity (or stellar mass) is well described by a log-normal function, characterized by its median ¯
1,175 citations
Cites methods from "Space Distribution and Luminosity F..."
...…function of galaxies has been measured from various redshift surveys of galaxies and is found to be well described by the Schechter function (Schmidt 1968; Loveday et al. 1992; Lin et al. 1996; Folkes et al. 1999; Madgwick et al. 2002); the morphological type of galaxies is found to be…...
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