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Binary merging constitutes a complementary mode of galaxy evolution to the canonical hierarchical clustering theory. This merger-driven evolution not only influences the galaxy mass distribution function, but may drive the main galactic activity cycles, such as starbursts and the activity in the nuclei (AGNs). In this paper, we use galaxy aggregation dynamics together with a possible merger-driven starburst and AGN phenomena, to study the effects of evlution of these consequential activities for the faint IRAS source counts and the infra-red background. We find that the strong evolution of IRAS 60$ mu m$ source count at flux range of $10 mJy sim 1 Jy$ is difficult to be explained only by the merger rate decrease with cosmic time. We need to assume a redshift dependent infrared burst phase of ultraluminous infrared galaxies (ULIGs) from the gas rich mergers at high redshift and the gas poor mergers at low redshift. The background intensity at 60$ mu m$ which we get from this aggregation evolution is a lower limit of only $1.9 nW m^{-2} sr^{-1}$, about half of those estimated by some previous models, but close to the lower end of the range derived by Malkan & Stecker (1998).
The shape of the curves defined by the counts of radio sources per unit area as a function of their flux density was one of the earliest cosmological probes. Radio source counts continue to be an area of interest, used to study the relative populatio
We present a submillimetre survey of seven high-z galaxy clusters (0.64<z<1.0) using the Submillimetre Common-User Bolometer Array (SCUBA) at 850 and 450 um. The targets, of similar richness and redshift, are selected from the Red-sequence Cluster Su
We perform fluctuation analyses on the data from the Spitzer GOODS survey (epoch one) in the Hubble Deep Field North (HDF-N). We fit a parameterised power-law number count model of the form dN/dS = N_o S^{-delta} to data from each of the four Spitzer
The distribution of galaxy morphological types is a key test for models of galaxy formation and evolution, providing strong constraints on the relative contribution of different physical processes responsible for the growth of the spheroidal componen
We discuss near-infrared star counts at the Galactic pole with a view to guiding the NGST and ground-based NIR cameras. Star counts from deep K-band images from the CFHT are presented, and compared with results from the 2MASS survey and some Galaxy m