Related papers: A left and right truncated Schechter luminosity fu…

The lifetime t_Q of the luminous phase of quasars is constrained by current observations to be between 10^6 and 10^8 years, but is otherwise unkown. We model the quasar luminosity function in detail in the optical and X-ray bands using the…

We search for the most suitable set of cosmological parameters that describes the observable universe. The search includes the possibility of quintessential flat universes, i.e., the analysis is restricted to the determination of the…

The recent compilation of quasar (QSO) X-ray and UV flux measurements include QSOs that appear to not be standardizable via the X-ray luminosity and UV luminosity ($L_X-L_{UV}$) relation and so should not be used to constrain cosmological…

We report hitherto unnoticed patterns in quasar light curves. We characterize segments of quasars' light curves with the slopes of the straight lines fit through them. These slopes appear to be directly related to the quasars' redshifts.…

Two new luminosity functions of galaxies can be built starting from three and four parameter generalized gamma distributions. In the astrophysical conversion, the number of parameters increases by one, due to the addition of the overall…

We present the $R$-band luminosity function for a sample of 18678 galaxies, with average redshift $z = 0.1$, from the Las Campanas Redshift Survey. The luminosity function may be fit by a Schechter function with $M^* = -20.29 \pm 0.02 + 5…

Several statistics are applied to groups and galaxies in groups in the Two degree Field Galaxy Redshift Survey. Firstly we estimate the luminosity functions for different subsets of galaxies in groups. The results are well fitted by a…

We determine the 22$\mu$m luminosity evolution and luminosity function for quasars from a data set of over 20,000 objects obtained by combining flux-limited Sloan Digital Sky Survey optical and Wide field Infrared Survey Explorer…

We discuss how luminosity and space distribution of galaxies are naturally linked in view of their multifractal properties. In particular we show that the mass (luminosity) function corresponding to a multifractal distribution in a given…

A relation between the variational slope, $s_F$ , and the mean absolute magnitude, $\langle M \rangle$, in the light curves of 58 spectroscopically confirmed quasars is measured with a dispersion of 0.15dex. Assuming it holds for quasars in…

We consider implications of our new model of quasar lifetimes and light curves for the quasar luminosity function (LF) at different frequencies and redshifts. In our picture, quasars evolve rapidly and the lifetime depends on both their…

We present a clustering analysis of QSOs over the redshift range z=0.3-2.9. We use a sample of 10558 QSOs taken from the preliminary catalogue of the 2dF QSO Redshift Survey (2QZ). The two-point redshift-space correlation function of QSOs…

We present the quasar luminosity function (LF) at $z = 7$, measured with 35 spectroscopically confirmed quasars at $6.55 < z < 7.15$. The sample of 22 quasars from the Subaru High-$z$ Exploration of Low-Luminosity Quasars (SHELLQs) project,…

We use the ROSAT All Sky Survey (RASS) to study the soft X-ray properties of a homogeneous sample of 46,420 quasars selected from the third data release of the Sloan Digital Sky Survey (SDSS). Optical luminosities, both at rest-frame…

We investigate the luminosity dependence of quasar clustering, inspired by numerical simulations of galaxy mergers that incorporate black hole growth. These simulations have motivated a new interpretation of the quasar luminosity function.…

In this paper we discuss the commonly-used limiting cases, or approximations, for two-point cosmic shear statistics. We discuss the most prominent assumptions in this statistic: the flat-sky (small angle limit), the Limber (Bessel-to-delta…

(Abridged) We explore the idea that the anti-hierarchical turn-off observed in the quasar population arises from self-regulating feedback, via an outflow mechanism. Using a detailed hydrodynamic simulation we calculate the luminosity…

We have computed the luminosity function for 389 field galaxies from the Canadian Network for Observational Cosmology cluster redshift survey (CNOC1), over redshifts z = 0.2-0.6. We find Schechter parameters M^* - 5 log h = -19.6 \pm 0.3…

The luminosity function of MS2255.7+2039 at z=0.288 is determined down to a total magnitude of R ~ 24, corresponding to M_R ~ -17 (H_0 = 50 km/s/Mpc). The data are corrected for incompleteness and crowding using detailed simulations. We…

We have developed a flexible framework for constructing physical models of quasar evolution that can incorporate a wide variety of observational constraints, such as multi-wavelength quasar luminosity functions (QLFs), estimated masses and…