Fundamental parameters and time evolution of mass loss are investigated for post-main-sequence stars in the Galactic globular cluster 47 Tucanae (NGC 104). ... We confirm the cluster's distance as d = 4611+213 -200 pc and age as 12 ТБ 1 Gyr. Horizontal branch models appear to confirm that no more red giant branch mass loss occurs in 47 Tuc than in the more metal-poor Я? Centauri, though difficulties arise due to inconsistencies between the models. ...

Stellar Clusters are very useful laboratories for empirically studying stellar evolution. ... All cluster stars are at the same distance . All cluster stars have the same physical age . ... CM diagram Young Cluster In this case we see the Main Sequence fully represented. The blue dots represent massive stars with short main sequence lifetimes. ... Thus, identifying the most massive star which is still on the main sequence is an effective means of determining the age of a stellar cluster. ...

Next: Other parameters of the Up: The Model Previous: Initial binary parameters . As we only deal with initially massive binary systems (their primary's mass is higher than 10 ), which are capable of evolving off the main sequence during less than years, the compact stars left behind stellar evolution are (in the case of the most massive stars) NSs and BHs. ... For a NS belonging to a binary, the evolution complicates as the secondary star evolves: for example, (recycling), etc. ...

... The most powerful and widely used methods to calculate the scattering matrix of a fractal cluster are based on the coupled dipoles methods (e.g. the Discrete Dipole Approximation, DDA) and the theory of light scattering by a cluster of spherical particles [2-4]. ... At present the procedure of calculation of the scattering matrix is well developed for both an oriented cluster of spherical particles and for chaotically oriented clusters of such particles [4]. ...

... The El Gordo Massive Galaxy Cluster . ... The above image of El Gordo is a composite of a visible light image from the Hubble Space Telescope , an X-ray image from the Chandra Observatory showing the hot gas in pink, and a computer generated map showing the most probable distribution of dark matter in blue, computed from gravitational lens distortions of background galaxies. ... Publications with keywords: galaxy cluster - dark matter . Publications with words: galaxy cluster - dark matter . ...

... 2014 April 22 . The El Gordo Massive Galaxy Cluster . Image Credit: NASA , ESA , J. Jee ( UC Davis ) et al. ... Dubbed "El Gordo", the seven billion light years ( z = 0.87) distant galaxy cluster spans about seven million light years and holds the mass of a million billion Suns. ... That galaxy is actually far in the background and has its image stretched by the gravitational lens action of the massive cluster. Follow APOD on: Facebook , Google Plus , or Twitter . ... About APOD | ...

... Science Users Information > Science Activities > PhD Thesis Topics offered by ESO Faculty Members > Thesis Topic: The onset of cluster formation near young high-mass stars . ... Observing with ESO Telescopes . ... ESO-MIDAS . ... ESO Data . ... We performed a NACO survey of massive young stellar objects (MYSOs) assessing the incidence of lower mass objects at angular scales 0:500 < d < 200 during the earliest, deeply embedded, phases of star formation. ... Return to list of thesis topics . ...

... We address a question if globular clusters (GC) in a protogalaxy could for some time evolve chemically as isolated systems, enriching themselves with heavy elements produced in first supernova events that follow initial star formation. We determine both the critical mass of a protoglobular cluster that is needed to retain the ejecta of the very first supernova, and the critical energy (i.e., number of supernovae) that is needed to expel the residual gas from a cluster of a given mass. ...

... Galactocentric distance dependences of the physical parameters of globular clusters. ... The straight line in (a) is the rms regression. The large circles in (b) show mean masses within narrow R intervals, and the solid lines show the rms regression fits for thick-disk and old-halo (left) and young-halo and corona (right) clusters. The dashed lines in (c) and (d) are upper and lower envelopes drawn by eye. discussion in the text | privious figure | next figure . ...

... 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" . ...

Simulating the Evolution of Stellar Clusters ? ... Resonant Exchange (few Myr) 4perturbed: 6000d, e=0.94 4CE + CE - DWD (0.35d) 2.0 MS 0.8 WD 4GR - merger after 10 Gyr M = 1.6 Msun Comparison with Data: Simulation of M67 H 12,000 single stars (KTG1993 IMF: 0.1 - 50 Msun ) H 12,000 binaries (q: uniform, e: thermal, a: flat-log, max 50 au) H Z = 0.02 H Circular orbit at Rgc = 8 kpc H Plummer Sphere in virial equilibrium 4M ~ 18700 Msun 4 Rt = 32 pc 4Trh ~ 200 Myr 4s ~ 3 km/s 4nc ~ 200 ...

... Kopylov, A.I., Kopylova, F.G. "Structure of galaxy groups and clusters and measurement of their masses", . ... Kopylova, F.G., Kopylov, A.I. "Peculiar motions of galaxy clusters and groups in the Hercules and Leo supercluster regions", . ... Kopylova, F.G., Kopylov, A.I. "Analysis of the properties of clusters of galaxies in the region of the Leo supercluster", . ... Kopylova, F.G., Kopylov, A.I. "Analysis of the properties of clusters of galaxies in the region of the Ursa Major supercluster", . ...

... Structure of Data . ... Catalog . ... In SAI OCL Catalog, we introduce our work on investigation of the Milky Way system of open star clusters. The main goal of our study is a search for new clusters using huge surveys. 168 new clusters have been already discovered by us using J,H,Ks data from 2MASS point source catalog. ... For 141 new clusters, we found their physical parameters using J,H,Ks data from 2MASS catalog and, for a number of clusters, our UBVRI CCD observational magnitudes. ...

... Posts tagged ?massive data? ... Tags: bimodality , chi-square minimization , Classification , CMD , Estimation , machine learning , massive data , model based , PCA , spectral analysis , spectroscopic , survey , VO . ... Algorithms arXiv Astro Bad AstroStat Bayesian CHASC Cross-Cultural Data Processing Fitting Frequentist Galaxies gamma-ray High-Energy Imaging Jargon Job Languages MC MCMC Meta Methods Misc News Nuggets Objects Optical Physics Quotes Spectral Stars Stat Timing Uncertainty X-ray . ...

... GSAOI Home . ... Science . ... Deep imaging at J , H , and K is required to identify all stellar objects, brown dwarfs, and planetary mass objects in the central region of the Orion Nebula Cluster down to masses comparable to that of Jupiter. This is required to establish the initial mass function, i.e., the number of stars of each mass that have formed, in this region of intense massive star formation. ... The fields of the GSAOI detectors are shown as four green squares in each frame. ...

... 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. ...

... Param?tres . ... Centre de Donn es sur les Satellites Naturels. Param tres et constantes . ... Satellites de Mars . Satellites de Jupiter . Satellites de Saturne . Satellites de Uranus . Satellites de Neptune . Satellite de Pluton . Masses de satellites . Dimensions de satellites . Param tres photom triques de satellites . Param tres de rotation et p les . El ments orbitaux moyens des satellites lointains de Jupiter, Saturne, Uranus et Neptune . ...

... L. Testi (1), P. Palla (2), A. Natta (2) . 1) Division of Physics, Mathematics and Astronomy, Caltech, MS 105-24, Pasadena, CA 91125, USA . ... We present large field infrared images of a sample of 45 Herbig Ae/Be stars. Stellar parameters, such as age and mass, have been derived for all of them in a consistent way. The images have been used to identify stellar groups or clusters associated with the Herbig Ae/Be star. ... Mantained by: Leonardo Testi . ...

The velocity corrected for infall of the Local Group towards Virgo is noted vvir . It is calculated as: vvir = vlg + 208 cos(theta) Where vlg is the velocity relative to the Local Group, 208 km/s is the infall velocity of the Local Group according to Theureau et al. 1998 and Terry et al. 2002 and where theta is the angular distance between the observed direction and the direction of the center of the Virgo cluster (SG 104 -2). ...

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