scholarly journals The Luminosity Function of Galaxies in Some Nearby Clusters

2021 ◽  
Vol 5 (2) ◽  
pp. 1-10
Author(s):  
Mariwan Ahmed Rasheed ◽  
Khalid K. Mohammad
Keyword(s):  
Luminosity Function ◽  
Velocity Dispersion ◽  
Absolute Magnitude ◽  
Normalization Constant ◽  
Minimization Method ◽  
Redshift Range ◽  
Magnitude Distribution ◽  
The Galaxy ◽  
The Absolute ◽  
Galaxy Luminosity Function

In the present work, the galaxy luminosity function (LF) has been studied for a sample of seven clusters in the redshift range (0.0 ≲ z ≲ 0.1), within Abell radius (1.5 h−1 Mpc), in the five SDSS passbands ugriz. In each case, the absolute magnitude distribution is found and then fitted with a Schechter function. The fitting is done, using the χ2 – minimization method to find the best values of Schechter parameters Ф* (normalization constant), M* (characteristic absolute magnitude), and α (faint-end slope). No remarkable changes are found in the values of M* and α, for any cluster, in any passband. Furthermore, the LF does not seem to vary with such cluster parameters as richness, velocity dispersion, and Bautz–Morgan morphology. Finally, it is found that M* becomes brighter toward redder bands, whereas almost no variation is seen in the value of α with passband, being around (−1.00).

The Faint End of the Galaxy Luminosity Function in Abell 426 and 539

1998 ◽  
Vol 116 (3) ◽  
pp. 1118-1124 ◽  
Author(s):  
Roberto De Propris ◽  
Christopher J. Pritchet
Keyword(s):  
Luminosity Function ◽  
The Galaxy ◽  
Galaxy Luminosity Function

scholarly journals The faint end of the galaxy luminosity function in moderate-redshift clusters

1997 ◽  
Vol 284 (4) ◽  
pp. 915-930 ◽  
Author(s):  
G. Wilson ◽  
I. Smail ◽  
R. S. Ellis ◽  
J. C. Warrick
Keyword(s):  
Luminosity Function ◽  
The Galaxy ◽  
Galaxy Luminosity Function

scholarly journals The galaxy luminosity function and its evolution withChandra

2008 ◽  
Vol 480 (3) ◽  
pp. 663-670 ◽  
Author(s):  
P. Tzanavaris ◽  
I. Georgantopoulos
Keyword(s):  
Luminosity Function ◽  
The Galaxy ◽  
Galaxy Luminosity Function

The K-Band Luminosity Function of Galaxies

1998 ◽  
Vol 179 ◽  
pp. 278-280
Author(s):  
J. P. Gardner ◽  
R. M. Sharples ◽  
C. S. Frenk ◽  
B. E. Carrasco
Keyword(s):  
Luminosity Function ◽  
Near Infrared ◽  
Mass Function ◽  
Solar Mass ◽  
The Galaxy ◽  
Statistical Studies ◽  
The Absolute ◽  
Number Counts ◽  
Luminosity Evolution ◽  
K Band

The luminosity function of galaxies is central to many problems in cosmology, including the interpretation of faint number counts. The near-infrared provides several advantages over the optical for statistical studies of galaxies, including smooth and well-understood K-corrections and expected luminosity evolution. The K–band is dominated by near-solar mass stars which make up the bulk of the galaxy. The absolute K magnitude is a measure of the visible mass in a galaxy, and thus the K–band luminosity function is an observational counterpart of the mass function of galaxies.

scholarly journals Impact of relativistic effects on the primordial non-Gaussianity signature in the large-scale clustering of quasars

2020 ◽  
Vol 499 (2) ◽  
pp. 2598-2607
Author(s):  
Mike (Shengbo) Wang ◽  
Florian Beutler ◽  
David Bacon
Keyword(s):  
Dark Energy ◽  
Power Spectrum ◽  
Luminosity Function ◽  
Large Scale ◽  
Relativistic Effects ◽  
Redshift Range ◽  
Cosmological Background ◽  
Relativistic Corrections ◽  
The Galaxy ◽  
The Impact

ABSTRACT Relativistic effects in clustering observations have been shown to introduce scale-dependent corrections to the galaxy overdensity field on large scales, which may hamper the detection of primordial non-Gaussianity fNL through the scale-dependent halo bias. The amplitude of relativistic corrections depends not only on the cosmological background expansion, but also on the redshift evolution and sensitivity to the luminosity threshold of the tracer population being examined, as parametrized by the evolution bias be and magnification bias s. In this work, we propagate luminosity function measurements from the extended Baryon Oscillation Spectroscopic Survey (eBOSS) to be and s for the quasar (QSO) sample, and thereby derive constraints on relativistic corrections to its power spectrum multipoles. Although one could mitigate the impact on the fNL signature by adjusting the redshift range or the luminosity threshold of the tracer sample being considered, we suggest that, for future surveys probing large cosmic volumes, relativistic corrections should be forward modelled from the tracer luminosity function including its uncertainties. This will be important to quasar clustering measurements on scales $k \sim 10^{-3}\, h\, {\rm Mpc}^{-1}$ in upcoming surveys such as the Dark Energy Spectroscopic Instrument (DESI), where relativistic corrections can overwhelm the expected fNL signature at low redshifts z ≲ 1 and become comparable to fNL ≃ 1 in the power spectrum quadrupole at redshifts z ≳ 2.5.

scholarly journals Galaxy Counts

1984 ◽  
Vol 78 ◽  
pp. 489-498
Author(s):  
J.A. Tyson
Keyword(s):  
Luminosity Function ◽  
Automated Detection ◽  
Color Evolution ◽  
Faint Galaxy ◽  
New Information ◽  
The Galaxy ◽  
Color Data ◽  
Photographic Survey ◽  
Galaxy Luminosity Function

AbstractCounts of faint galaxies should reveal any evidence of galaxy luminosity or color evolution, as well as new information on the faint end of the galaxy luminosity function. The FOCAS automated detection and classification software is reviewed, and results of the deep 4m PF photographic survey to 24th magnitude in 23 fields covering 9 sq. degrees are presented. Color-magnitude plots for stars and galaxies are shown, and galaxy color evolution is discussed. Evidence is found for a faint galaxy blue trend at 22-24 J mag. However, the k-correction becomes so severe at redshift ~1 that the intrinsically fainter galaxies are emphasized in any magnitude-limited survey. No unambiguous evidence is found for evolution. New 4m limit CCD multi-color data are shown and discussed. The limiting magnitude for detection is 27th J magnitude in 2 hours integration. The data exclude evolution starting at any one epoch for z<10.

scholarly journals The galaxy–halo connection in modified gravity cosmologies: environment dependence of galaxy luminosity function

2019 ◽  
Vol 488 (1) ◽  
pp. 782-802 ◽  
Author(s):  
N Chandrachani Devi ◽  
Aldo Rodríguez-Puebla ◽  
O Valenzuela ◽  
Vladimir Avila-Reese ◽  
César Hernández-Aguayo ◽  
...  
Keyword(s):  
Modified Gravity ◽  
Luminosity Function ◽  
Cold Dark Matter ◽  
Density Field ◽  
High Density ◽  
Gravity Models ◽  
The Galaxy ◽  
Galaxy Halo ◽  
Environment Dependence ◽  
Galaxy Luminosity Function

Abstract We investigate the dependence of the galaxy–halo connection and galaxy density field in modified gravity models using the N-body simulations for f(R) and nDGP models at z = 0. Because of the screening mechanisms employed by these models, chameleon and Vainshtein, haloes are clustered differently in the non-linear regime of structure formation. We quantify their deviations in the galaxy density field from the standard Λ cold dark matter (ΛCDM) model under different environments. We populate galaxies in haloes via the (sub)halo abundance matching. Our main results are as follows: (1) The galaxy–halo connection strongly depends on the gravity model; a maximum variation of ${\sim }40{{\ \rm per\ cent}}$ is observed between halo occupational distribution (HOD) parameters; (2) f(R) gravity models predict an excess of galaxies in low-density environments of ${\sim }10{{\ \rm per\ cent}}$ but predict a deficit of ${\sim }10{{\ \rm per\ cent}}$ at high-density environments for |fR0| = 10−4 and 10−6 while |fR0| = 10−5 predicts more high-density structures; nDGP models are consistent with ΛCDM; (3) different gravity models predict different dependences of the galaxy luminosity function (GLF) with the environment, especially in void-like regions we find differences around ${\sim }10{{\ \rm per\ cent}}$ for the f(R) models while nDPG models remain closer to ΛCDM for low-luminosity galaxies but there is a deficit of ${\sim }11{{\ \rm per\ cent}}$ for high-luminosity galaxies in all environments. We conclude that the dependence of the GLF with environment might provide a test to distinguish between gravity models and their screening mechanisms from the ΛCDM. We provide HOD parameters for the gravity models analysed in this paper.

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