... Stellar Evolution is driven entirely by the never ending battle between Pressure and Gravity . As imbalances are reached, the star is driven to find a new Energy source. ... Pressure and gravitational forces are equal, the star is stable and its core is sufficiently hot to fuse Hydrogen into Helium More about main sequence stars . ... The luminosity generated by the core fusion of Helium into Carbon is far greater than the shell luminosity associated with the fusion of Hydrogen into Helium. ...

... 172 ] Briefly, the count rate at the detector from a source at a redshift z is . ... Figure 55 shows the ``Green functions'' for the double compact binary merging rate   evolution assuming no collapse anisotropy. ... Another way that diverse peculiarities in the - distribution induced by the sources evolution could arise is connected with a possible non-monotonic character of the star formation rate in galaxies. ... 22 ] Figure  56 shows two-dimensional cuts through the parameter space. ...

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. ...

... We demonstrate through numerical simulations that model parameters estimated with our technique are essentially bias-free, even when the average number of counts per bin is 1. ... The IW technique avoids such biases by estimating through successive iterations, where for each iteration, j, , and the best-fit parameters are determined by minimization of . ... In our sample, we find that the minimum values and best-fit parameters converge after about 6 iterations. ...

Observed maximum rotation velocity uncorrected for inclination effect. This quantity is calculated from 21-cm line widths at different levels and/or rotation curves (generally in H_alpha). ... These data are characterized by some secondary parameters: telescope, velocity resolution, level of the 21-cm line width and bibliographic reference. ... we start from a standard sample (a set of measurements giving a large and homogeneous sample). ... HyperLeda . ...

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 ? ...

... There are compelling reasons for the pulsar community to utilise a standard data storage format. For example, standardisation of file formats significantly decreases the amount of effort required to integrate new instruments into the analysis chain. ... Accordingly, we have defined PSRFITS as a standard FITS-based format for pulsar data files. ... For example, the first line of Processing History HDU contains information about the data acquisition program and the initial structure of the file. ...

... 05/09/2013 Galaxy Evolution over Five Decades - Cambridge 2013 Nuclear activity and environment Effect of environment on AGN is not completely clear yet. ... 05/09/2013 Galaxy Evolution over Five Decades - Cambridge 2013 Effect of the mass Mass slices ­ optical and radio AGN overall interaction one-on-one interaction relative location 05/09/2013 Galaxy Evolution over Five Decades - Cambridge 2013 Stratified study Stratifed study that considers several strata of mass. ...

... List of SAS threads . This thread contains a (very!) simple standard XSPEC session for fitting data from the X-ray cameras. ... Start XSPEC . ... Load spectrum data: . ... response 1 PN.rmf . ... plot data . Fig.1: XSPEC data plot . Ignore bad channels in data: . ... The latter, the maximum number of channels to bu summed. plot data with model adjustment and e.g. the residuals (alternatives, ratio data/model, absolute chi-squared, etc) . ... Fig.2: XSPEC data, model and residual plot . ...

... VLA observations and Tully-Fisher distances of gas-poor spiral galaxies in the Virgo Cluster Region . ... The HI-H2 Pressure Relation In Early-Type Galaxies . ... Tracing evolution of early-type spirals through the neutral hydrogen window . ... An Arecibo HI 21-cm Absorption Survey of Rich Abell Clusters . ... The Arecibo Ultra-Deep Survey . ... Absorption in varying galactic environments seen in HI surveys . ... Early-type galaxies with neutral hydrogen in the Virgo cluster from the ALFALFA survey ...

... 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. ...

... Posts tagged ?parameter estimation? ... Leccardi & Molendi (2007) have a paper in A&A ( astro-ph/0705.4199 ) discussing the biases in parameter estimation when spectral fitting is confronted with low counts data. Not surprisingly, they find that the bias is higher for lower counts, for standard chisq compared to C-stat, for grouped data compared to ungrouped. ... Tags: bias , C-stat , chi-square , chisq , Cstat , Fitting , parameter estimation , Peter Freeman , spectra . ... 1 Comment . ...

... Tte tables of ionosphere and plasmasphere parameters are contained in a file param.tbl. ... Latitude Longitude Numbers of tables for (degree) (degree) Month Wm=10 Wm=100 Wm= 150 80 30 March 1 - 3 397-399 793-795 80 150 March 4 - 6 400-402 796-798 80 270 March 7 - 9 403-405 799-801 60 30 March 10 - 12 406-408 802-804 60 150 March 13 - 15 409-411 805-807 60 270 March 16 - 18 412-414 808-810 40 30 March 19 - 21 415-417 811-813 40 150 March 22 - 24 418-420 814-816 40 270 ...

Next: Buffer Manipulation Up: Programming in C Previous: Compiler Options . Listed below are nearly all the ANSI C standard library functions. The header file where related definitions are stored are given. These may vary on some systems so check local reference manuals. ... More info can be obtained from online man calls or reference manuals. Buffer Manipulation . Character Classification and Conversion . ... File Manipulation . ... Wed Sep 14 10:06:31 BST 1994 ...

Topics covered by the IAU Symp. ... Do all galaxies have stellar halos? ... Stellar tracers of the MW halo and nearby galaxies; the stellar population of star clusters and their contribution to the galaxy halos . ... NEW: Scientific program of the IAU Symposium 317 can be downloaded here . ... GLOBAL PROPERTIES OF STELLAR HALOS FROM THE MILKY WAY TO EXTERNAL GALAXIES . ... DISCRETE CONSTITUENTS OF STELLAR HALOS IN THE MILKY WAY AND IN EXTERNAL GALAXIES : PLANETARY NEBULAE and GLOBULAR CLUSTERS . ...

... A Hubble diagram for Quasars . ... The potential use of such relation as a cosmological probe is obvious: assuming no redshift evolution of the relation, the observed X-ray flux is a function of the observed UV flux, the redshift, and the parameters of the adopted cosmological model. ... In this framework, Guido Risaliti and Elisabeta Lusso (INAF-Arcetri Observatory) have recently published in the Astropysical Journal the first Hubble Diagram for quasars suitable for cosmological measurements . ...

... Mass loss Recipes | ... Mass Loss is the most important "driver" of stellar evolution in massive stars. ... The final goal is to predict mass loss over the entire evolution of a massive star at all cosmological epochs. ... Very Massive Stars are objects up to 300 times the mass of the Sun. ... Mass-loss rates increase dramatically when objects cross a critical Eddington Gamma factor (Vink et al. ... I have recently edited a book on "Very Massive Stars" including a mass-loss "chapter" . ...

... The sample of the Local Volume galaxies (distance smaller than 10 Mpc) gives a unique opportunity to study the properties of galaxies including the weakest objects: the absolute magnitude M B -10 and the virial mass M vir 10 9 M x263C;. ... Luminosity function of the Local Volume galaxies. ... The luminosity functions for galaxies are presented: red dashed line - from the 2dFGRS survey (Norberg et al. 2002); blue dash-dotted line - from the SDSS survey (Blanton et al. ...

Following are instructions to build and install the programs in this distribution. Make sure that you have all necessary tools for building executables. ... The automatic build process expects a configuration file called Config.local . ... The configuration file specifies the directory in which to install the binaries, as well as control over the generation of debugging code and reference clock support. ... Cleans out object files, programs and temporary files. make distclean . ...

Cosmology - Science of the Universe in General. ... Cosmological Paradoxes of Classical Cosmology. ... Classical Theory of Gravitation. Space-Time of Special Theory of Relativity. Incompatibility of Special Theory of Relativity and Classical Theory of Gravitation. ... Space-Time of General Theory of Relativity. ... Tensor Algebra. ... Effects of General Theory of Relativity in Solar System (Motion of Planet Perihelion, Deflection of Light Rays, Gravitation Red Shift, Delay of Radar Echo). ...