... 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. ...

... The large body of near infrared observations presented in Testi et al. (1997; 1998) are analysed with the aim of characterizing the young stellar clusters surrounding Herbig Ae/Be stars. The results confirm the tendency of early Be stars to be surrounded by dense clusters of lower mass "companions", while Ae stars are never found to be associated with conspicuous groups. ... Only the most massive stars (10-20Msun) are found to be associated with dense (10^3 pc^-3) stellar clusters. ...

Mikhail Medvedev (University of Kansas) HEA- 2007 , IKI, Moscow Missing baryons in inter-cluster gas Afshordi, et al, 2007 , astro-ph/0612700 35% +/- 8% Sample of 260 clusters WMAP SZ 3yr data Compared with 11 simulated clusters Assumed: Universal NFW profile Self-similarity Isothermal gas Possible explanations Observed stellar mass in galaxies: ~ 10% (Lin, et al, ... Simulations indicate that the effect is small (Dolag, et al, 2004) Can account for ~1-2% missing mass at most ...

... The overall globular cluster population is divided by gap in the metallicity function at [Fe/H]=-1.0 into two discrete groups with well-defined maxima at [Fe/H]=-1.60?0.03 dex, and -0.60?0.04 dex. ... Clusters with extremely blue horizontal branches occupy a spherical volume of radius ~ 9 kpc, have high rotational velocities ( V rot =77?33 km/s), have substantial and equal negative radial and vertical metallicity gradients, and are, on average, the oldest group (the old-halo subsystem). ...

... For this paper: postscript PPEUC CMB index 1 Introduction.. ... We present a new model for the formation of spherically symmetric clusters in an expanding Universe. Both the Universe and the collapsing cluster are governed by the same pressure less fluid equations for which a uniform initial density profile is assumed. ... The computation of photon paths allows us to evaluate the gravitational effects imprinted on a Cosmic Microwave Background (CMB) photon passing through such an evolving mass. ...

... XX, 2000 F. Combes, G. A. Mamon and V. Charmandaris, eds. Mass and Age of the Nuclear Star Cluster in IC 342 Roeland P. van der Marel, Torsten B˜oker 1 Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, U.S.A. William D. Vacca Institute for Astronomy, Honolulu, HI 96822, U.S.A. Abstract. ... Here we summarize the results of a study of the mass and age of the nuclear cluster in the nearby Scd spiral IC 342, based on 12 CO (2­0) bandhead spectroscopy. ... 1999). ...

... Science . ... The goal is to bring together two communitities: the one working on star formation (mostly galactic) and the one working on the formation of young massive clusters (mostly extra-galactic). We will link galactic with extra-galactic work, optical/NIR techniques with sub-mm/mm/radio ones, the formation of stars with the one of massive star clusters - observations and theory. ... Coordinated by Marina Rejkuba (abstract) . ... How did star formation proceed in Globular Clusters? ...

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. ...

... Gravitational wave search provides insights into galaxy evolution and mergers . ... galaxies . ... Globular cluster NGC 2808, elliptical galaxy NGC 2986, and the Sextans Dwarf . ... Open cluster NGC 2818, spiral galaxy NGC 2964, and spiral galaxy NGC 2976 . ... What are typical star-to-star distances in globular clusters compared to stellar distances in our region of the galaxy? ... RELATED TOPICS: GLOBULAR CLUSTERS . ... Get instant access to subscriber content on Astronomy.com! ...

... Editor's choices for the most educational Astronomy Pictures of the Day about clusters of galaxies: . APOD: 2006 March 21 - The Coma Cluster of Galaxies . ... APOD: 2005 November 22 - A Galactic Collision in Cluster Abell 1185 . ... A prominent example occurs on the left of the above image of the rich cluster of galaxies Abell 1185. ... Recent observations of Abell 1185 have found unusual globular clusters of stars that appear to belong only to the galaxy cluster and not to any individual galaxy. ...

... Australia Telescope Compact Array . ... Compact Stellar Systems in the Fornax Cluster: Super-massive Star Clusters or Extremely Compact Dwarf Galaxies? ... We suggest that these objects are either super-massive star clusters (intra-cluster globular clusters or tidally stripped nuclei of dwarf galaxies) or a new type of low-luminosity compact elliptical dwarf (``M32-type'') galaxy. ... Keywords: galaxies: star clusters -- galaxies: dwarf -- galaxies: formation . ... Properties of the compact objects ...

... BIG BANG COSMOLOGY, GALACTIC CLUSTERS, SPACE DENSITY, UNIVERSE, FRAGMENTATION, HYDROGEN CLOUDS, INTERSTELLAR GAS, SPATIAL DISTRIBUTION, VOIDS . ... The fragmentation theory of the formation of the large scale structure of the universe is explained and contrasted with the continuous clustering theory. ... Use: Authors Title Abstract Text Text Query with Keywords Return: Query Results Query Form Database: Astronomy Instrumentation Physics and Geophysics ABSTRACT QUERY USER FEEDBACK HELP ...

... 633Slee+ Fifty-eight fields near rich clusters of galaxies were surveyed with the Very Large Array using scaled arrays in the B/C and/or C/D configurations at 1.5 GHz and 4.9 GHz. The fields were centered on steep spectrum sources in or near clusters that were earlier surveyed with lower resolution telescopes. ... The columns are : . Column 1 Cluster Field (Z1518 = Zw1518.8+0747) . Column 2 distance of source from cluster centre in Abell radii . ... Column 5 1.5 GHz flux (mJy) . ...

... Chandra Observation of DEEP2 Galaxy Groups and Clusters . ... Monday: 'Normal' Galaxies, Tuesday: Cluster Formation and Evolution . ... Statistics of galaxy groups in ultradeep XMM surveys. ... What can multiwavelength observations tell about cluster/group formation as well as galaxy evolution? ... I will present results from a Chandra study of eight low-redshift clusters that has systematically measured the AGN fraction in clusters and describe their spatial, kinematic, and host galaxy...

Astronomy Picture of the Day . The Coma Cluster of Galaxies . ... The Coma Cluster of Galaxies pictured is one of the densest clusters known - it contains thousands of galaxies . ... Most galaxies in Coma and other clusters are ellipticals , while most galaxies outside of clusters are spirals . ... Publications with keywords: cluster of galaxies - Coma Cluster - cluster . Publications with words: cluster of galaxies - Coma Cluster - cluster . ... Inside the Coma Cluster of Galaxies . ...

... Next: Unsupervised Catalog Classification Up: Object Detection and Previous: Classification of Objects . ... Multi-resolution allows for image analysis in terms of different scales. ... This approach is used for the detection (and subsequent analysis) of globular cluster systems around elliptical galaxies, and for image characterization and object trawling in large image databases. ... The applicability of this approach to object detection in large image collections has been investigated. ...

... 1st Announcement IAU Symposium 312 Star Clusters and Black Holes Across Cosmic Time, Beijing, China, Aug. 25-29, 2014 . ... SUBJECT: 1st Announcement IAU Symposium 312 Star Clusters and Black Holes Across Cosmic Time, Beijing, China, Aug. 25-29, 2014 . ... which will be held in Beijing, P.R. China, from August 25-29, 2014, hosted by Chinese Academy of Sciences . ... China), . ... 1st Announcement IAU Symposium 312 Star Clusters and Black Holes Across Cosmic Time, Beijing, China, Aug. ...

Title: A New Model of the Gravitational Lens 0957+561 and a Limit on the Hubble Constant . Authors: Norman A. Grogin , Ramesh Narayan (Harvard Univ.) ... Title: ROSAT/PSPC observation of the distant cluster CL0939+472 . ... Title: Interaction in the Bimodal Galaxy Cluster A3528 . ... Title: Cosmological Implications of Galaxy Cluster Evolution . ... Title: Galaxy Cluster Virial Masses and Omega . ... Matches 201 to 222 from a total of 222 matches for the search pattern galaxy cluster . ...

... A2642 Date Received: 2011-Jun-02 17:40:47 Technical Page Proposal Type: General Category: Sub-Category: Observation Category: Total Time Requested: Minimum Useful Time: Prop osal Title: ABSTRACT: Regular Astronomy Spectroscopy Extragalactic 6.0 Hours 45 min 21 cm HI Observations of intermediate-z Clusters of Galaxies We propose to detect and study the global neutral atomic gas properties of a sample of 4 intermediate-redshifts (0.15 <z <0.2) clusters of galaxies with the Arecibo telescope. ...

J/AstL/vol/page SAI Open Clusters Catalog (Glushkova+, 2009) ================================================================================ Automated search for star clusters in large multiband surveys. ... Color excesses E(B-V), distance moduli and ages were determined for 141 new and 27 known, but poorly studied clusters. We present the Sternberg Astronomical Institute Open Clusters Catalog (SAI OCL Catalog) of coordinates, diameters and main physical parameters of these clusters. ...