Results 31 to 40 of about 224,275 (141)
On the Number of Galaxies at High Redshift
Galaxies, 2015 The number of galaxies at a given flux as a function of the redshift, z, is derived when the z-distance relation is non-standard. In order to compare different models, the same formalism is also applied to the standard cosmology.
Lorenzo Zaninetti
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The ISO 170um Luminosity Function of Galaxies [PDF]
, 2005 We constructed a local luminosity function (LF) of galaxies using a flux-limited sample (S_170 > 0.195Jy) of 55 galaxies at z < 0.3 taken from the ISO FIRBACK survey at 170um.
Dennefeld, Michel +5 more
core +2 more sources
The Planetary Nebula Luminosity Function [PDF]
Proceedings of the International Astronomical Union, 2006 AbstractAlthough the method has no theoretical explanation, the [Oiii]λ5007Å planetary nebula luminosity function (PNLF) is an extremely valuable tool for obtaining accurate (< 10%) extragalactic distances out to ~ 18 Mpc. Because the PNLF works in large galaxies of all Hubble types, it is one of the best tools we have for cross-checking the results
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The Galaxy Luminosity Function and Luminosity Density at Redshift z=0.1 [PDF]
, 2002 Using a catalog of 147,986 galaxy redshifts and fluxes from the Sloan Digital Sky Survey (SDSS), we measure the galaxy luminosity density at z = 0.1 in five optical bandpasses corresponding to the SDSS bandpasses shifted to match their rest-frame shape ...
Andrew J. Connolly +22 more
core +2 more sources
Tracing Galaxy Evolution by Their Present-Day Luminosity Function
Open Astronomy, 2011 Galaxy luminosity functions are derived for different morphological types and various colors of galaxies, to trace the evolutionary effects which a priori should be different for void and supercluster galaxies.
Tempel E.
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Radio Luminosity Functions [PDF]
Symposium - International Astronomical Union, 1996 Luminosity functions give the space densities of source populations as functions of spectral luminosity. They constrain source physics, clustering, cosmological evolution, and contributions to the radiation background. Extragalactic radio sources span eight decades of luminosity, so dividing them into luminosity ranges effectively separates them by ...
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Luminosity Functions of Planetary Nebulae [PDF]
Symposium - International Astronomical Union, 1997 Planetary nebulae have recently been shown to be useful as standard candles (Ciardullo et al. 1989, ApJ, 339, 53; Jacoby 1989, ApJ, 339, 39). Distances to many galaxies have been determined by fitting a planetary nebula luminosity function (PNLF) to observations of the OIII 5007å line of PNe.
Marcelle Tremblay, Sun Kwok
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The Structure Function of Mid-infrared Variability in Low-redshift Active Galactic Nuclei
The Astrophysical Journal, 2023 Using the multi-epoch mid-infrared (MIR) photometry from the Wide-field Infrared Survey Explorer spanning a baseline of ∼10 yr, we extensively investigate the MIR variability of nearby active galactic nuclei (AGNs) at 0.15 < z < 0.4.
Suyeon Son, Minjin Kim, Luis C. Ho
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Energies, 2023 To restrain the environmental impact of modern SI engines, igniters must guarantee stable combustions with low cycle-to-cycle variability in extreme operating conditions (high EGR, ultra-lean), via high energy release in the combustion chamber.
Roberto Martinelli +5 more
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On the origin of the galaxy luminosity function [PDF]
Monthly Notices of the Royal Astronomical Society, 2004 Evidence is summarized that suggests that when a protogalaxy collapses, a fraction $f$ of its gas fails to heat to the virial temperature, where $f$ is large for haloes less massive than the value $M^*$ associated with $L^*$ galaxies. Stars and galaxies form only from the cool gas fraction.
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