A Test of Galaxy Evolutionary Models Via Angular Sizes M. Im S. Casertano, R. E. Griffiths, & K. U. Ratnatunga (The Johns Hopkins University) The relationship between angular size, magnitude, and redshift of faint galaxies is explored as a potential tool to distinguish between different galaxy evolutionary models. ... The mild lumi­ nosity evolution model predicts more luminous galaxies of large angular size at high redshift, as does a standard no evolution model. ... 25) with redshift higher than z ? ...

... Our resulting sample of ELGs presented in Tables 2 and 3 is not artificially biased to any specific type of galaxies. ... Since we are looking for selection of a sample of Case BCGs, it is interesting to examine how the detected BCGs are connected with Case emission-line codes. ... Altogether BCGs comprise about 60 % of all Case ELGs which display emission lines in our spectra, or about 44 % of all Case galaxies with some emission-line code. ... Among those with the code ``w'' about 40 % are BCGs. ...

The project of the informational system creation on the problem of evolution of radio galaxies, as a part of the "Big Trio" project aimed on studing of distant radio galaxies, is designed. This system allows a user to operate with simulated curves of spectral energy distributions (SED) to estimate ages and redshifts by photometry data. Authors use SEDs of several models for different types of galaxies. ... The HTTP and e-mail access is organized to this system. ...

... Posted by hlee . ... Click for what was appeared in arXiv this week. Continue reading ?[ ... Category: arXiv , MCMC , Uncertainty | ... Since I began to subscribe arxiv/astro-ph abstracts, from an astrostatistical point of view, one of the most frequent topics has been photometric redshifts . ... Just searching by photometric redshifts in google scholar and arxiv.org provides more than 2000 articles since 2000. ... Category: Algorithms , arXiv , Data Processing , Galaxies , Stat | ...

In this gallery are many images of Low Surface Brightness Galaxies which have recently been discovered and analyzed. ... The central surface brightness of this galaxy is 24.28 . Malin 2 This galaxy is another huge disk galaxy with a scale length of 15 kpc and a redshift of 15000 km/a. The high surface brightness knot in one of its spiral arms actually has the same color, luminosity and H-alpha equivalent width as the entire Large Magellanic Cloud . ... Truly it is a Low Surface Brightness Galaxy. ...

... According to the most popular cosmological paradigm, the greater part of the galaxy mass is accumulated in the dark matter halo. ... The polar ring galaxies (PRGs) reveal external rings or disks of gas, dust and stars rotating in a plane roughly perpendicular to the disk of the central galaxy. ... The shape of the dark halo in the model was chosen so as to achieve the best fit to the observed rotation of both galaxies themselves and their polar rings. ... The SPRC-7 galaxy. ...

... ATNF Home . ... About ATNF overview . News | ... Australia Telescope Steering Committee . ... Australia Telescope User Committee . ... Murchison Radio-astronomy Observatory . ... Parkes radio telescope . ... Mopra radio telescope . ... Visiting Parkes radio telescope . ... Parkes radio telescope webcam . ... Now, new Australia Telescope observations of the polar ring galaxy NGC 4650a suggest that the dark matter in this galaxy lies in a flattened distribution aligned with the polar ring. ...

... 1 Figure 1: The density distribution in R­Z plane Figure 2: The luminosity distribution in R­Z plane for Maxwellian kick velocity (75 km/s) 2 Figure 3: The luminosity distribution in R­Z plane for Maxwellian kick velocity (150 km/s) n(R; Z) = nHI + 2 \Delta nH2 nH2 = n 0 \Delta exp џ \GammaZ 2 2 \Delta (70pc) 2 – If 2kpc џ R џ 3:4kpc, then nHI = n 0 \Delta exp џ \GammaZ 2 2 \Delta (140pc \Delta R=2kpc) 2 – ; For R џ 2kpc n(R; Z) was assumed to be constant: n(R ! ...

... Colours of stars and galaxies hold information on intrinsic and extrinsic parameters, such as stellar temperatures and galaxy populations, selective absorption and colour changes due different dust contents and inclination angles of galaxies, as well as galaxy redshifts and evolution. ... The colour magnitude diagram of 65000 galaxies to which all above-mentioned quantities and others contribute can only be explained by comparison with simulations. ... Colours are also of technical help. ...

... Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2001 September 4 . 2dF Sees Waves of Galaxies . Credit: Matthew Colless ( ANU ) et al. , 2dF Galaxy Redshift Survey . ... The 2dF system measures galaxy redshifts , allowing astronomers to estimate distances to some of the millions of galaxies visible, and hence to make a three-dimensional map of the local universe. ... About APOD | ...

... This represents the first HI selected sample covering the core and the outskirts of a local cluster of galaxies. ... Optically selected samples miss a considerable number of low luminosity, low surface brightness galaxies underestimating by almost a factor 2 the number of HI rich galaxies present in the cluster volume. ... Right: The g band luminosity function for galaxies in the A1367 volume as obtained from the optically (circles) and HI (histogram) selected sample. ...

... Abell 2744: Pandoras Cluster of Galaxies . ... Credit Copyright: NASA , ESA , J. Merten ( ITA , AOB ), D. Coe ( STScI ) Explanation: Why is this cluster of galaxies so jumbled? Far from a smooth distribution, Abell 2744 not only has knots of galaxies, but the X-ray emitting hot gas (colored red) in the cluster appears distributed differently than the dark matter . ... Publications with keywords: galaxy cluster - dark matter - hot gas . ... The Hydra Cluster of Galaxies . ...

... Cross-shaped galaxy ZGC 2315+03 (Fig.1) has been described by Zwicky (1971) as ``post-eruptive or the result of the crossing of a compact galaxy through an edge-on spiral'' . This object was included in the Polar-Ring Catalog (C-71) by Whitmore et al. (1990) as a possible candidate for Polar-Ring Galaxies (PRG). ... One of them is galaxy 'disk' and the other is 'polar-ring'. ... The facts against the polar-ring nature of ZGC 2315+03 can be summarized as follows: . ...

Since the first stars and then galaxies formed the Universe has been an immense factory converting neutral gas into stellar material. ... In this seminar I will discuss recent results from the Galaxy And Mass Assembly (GAMA) survey, probing the assembly of stellar mass though both in-situ star formation (as traced by multiple SFR indicators) and interactions (both mergers and interaction induced star-formation) - in galaxies spanning ~4 decades in stellar mass. ...

... Galaxy Evolution home . Cavendish Astrophysics . ... Cosmological evolution of star-forming galaxies . ... Local Information . ... Mappings: Mappings is a code for the calculation of (optical) line ratios under a wide variety of conditions Mappings (Binette) . ... ZEUS is the fluid dynamics code we use for our simulations and is available on the Beowulf cluster and the Suns. It comes in a variety of flavours: ZEUS-3D full 3D code with lots of other options; can also run 2D simulations . ...

... SteMaGE is a research program aimed at improving the way we measure stellar mass in galaxies, map its distribution and understand how it affects galaxy evolution. ... At each position in a galaxy the stellar mass density is computed by comparing the observed optical/NIR emission with a library of models that reproduce different SFHs and dust attenuation. ... This new standard will be used to estimate the local SMF, providing a new unbiased reference for galaxy evolution models. ...

... Armagh Observatory, College Hill, Armagh BT61 9DG, +44 (0)28 3752 2928 . ... The number distribution is shown in the middle panel. The right panel illustrates the distribution of chirp mass due to different DWD types, normalized by the total number (2.76†Ч108) of DWDs in the Galaxy (bin size M = 0.001M ? ... The frequency spectra of DWD strain amplitude and number distribution are presented as a function of galactic component, DWD type, formation channel, and metallicity. тИТ4.5. ...

... Visible Distribution of Galaxies. ... Features of Elliptical, Lens-Shaped, Spiral and Irregular Galaxies. Galaxies with Bar. ... Distribution of Surface Brightness of Surface and Spiral Galaxies. ... Color Characteristics of Galaxies. ... Methods of Galaxies' Mass Determination. ... Hidden Mass of Spiral Galaxies. ... Features of Dark Matter Distribution in E and SO Galaxies. ... The Whole Number of Galaxies and Their Density by the Results of Observation on the 'Hubble' Space Telescope. ...

... Next: Cheating Poisson: A Up: Statistical Analysis Previous: Spatial Models and . ... The spatial distribution of stars in the Local Group dwarf irregular galaxy NGC 6822 has been studied, using recent positions and deep photometry for about 15,000 stars in the galaxy. Based on photometrical data, OB stars and red stars could be studied separately. Spatial statistical tools have been applied to the analysis of the spatial structure. ... Figure: Model selection by the aid of CAIC . ...

... The obtained results lead to the following conclusions: a) the heavy element enrichment had taken place in the Galaxy in a few bursts of its activity rether than in a continuons manner; b) these bursts occured during the callapse of the early Galaxy; c) the star formation had been inhibited in the time of the bursts; d) the metal enrichment did not proceed in the periods of star formation, between these bursts of activity. ...