Next: Rotation Periods of PMS Stars Previous: Direct Monitoring of PMS Stars . Studies using direct detection of periods via rotational modulation have been carried out on stars in several young clusters which are near the zero--age main sequence (ZAMS), including the Hyades, the Pleiades and Persei (see Radick 1988, Schaller et al . ... Rotation in ZAMS clusters has a strong mass dependence. High--mass stars tend to rotate much more quickly than the low--mass stars. ...

... The Hydra Cluster of Galaxies . ... 16.04.2001 . ... Most of a cluster's mass , however, appears to be in a form too dark to see , as analyses of the distribution of X-ray light , gravitational lensing , and internal motions indicate. Abell 1060, as the above cluster is also known, appears to have an even higher fraction of dark matter than seen in a similar cluster, a situation astronomers cannot easily reconcile with both clusters forming solely from gravitational attraction. ... April 2001 . ...

... ESO, the European Southern Observatory . ... ESO's Governing Bodies . ... Green ESO . ... This artistтАЩs impression shows the Milky Way galaxy. The blue halo of material surrounding the galaxy indicates the expected distribution of the mysterious dark matter, which was first introduced by astronomers to explain the rotation properties of the galaxy and is now also an essential ingredient in current theories of the formation and evolution of galaxies. ... Dark Matter , Milky Way . ... Milky Way . ...

... 2004 January 20 . Unexpected Galaxy String in the Early Universe . ... Explanation: How could such a long string of galaxies form so early in the universe? Several new measurements of galaxies and clusters in the early universe are reporting structures involving galaxies and clusters that are larger than expected with the new standard "dark-energy" cosmology . The controversy centers on the inability of a dark-energy dominated universe to create such large structures. ... About APOD | ...

Tidal Triggering of Star Formation and the Butcher­Oemler Effect Mark J. Henriksen (University of Alabama and UCLA) Gene Byrd (University of Alabama) We have calculated the expected level of star formation which would be induced in a disk galaxy falling into the potential well of a cluster of galaxies due to: drag force from the ICM, the radial tidal force from the cluster potential, and the lateral tidal force from the cluster potential. ... Table 4 contains the downstream post­ shock critical mass. ...

. F igure . 7. Distributions of height above the Galactic plane for (a) thick-disk, (b) old-halo, and (c) young-halo clusters. The curves are exponential least-squares approximations of the corresponding distributions. discussion in the text | privious figure | next figure .

... The (very) slow rotation of magnetic Ap stars. ... Magnetic stars in young clusters and associations. ... Magnetic fields in low-mass stars from high-resolution infrared spectroscopy. ... Magnetic field measurements of late B-type starss. ... Measurement of magnetic field of FK Com. ... Magnetic field of white dwarfs. ... The magnetic star evolution project (teleconference). ... Conference-2014 . Program . ... Laboratory for the Stellar Magnetism Study of SAO of RAS . ...

... Bisnovatyi-Kogan, Gennady S.; Merafina , Marco; Vaccarelli , Maria Rosaria; Spherically Symmetric Stellar Clusters with Anisotropy and Cutoff Energy in Momentum Distribution. ... We construct numerical models of spherically symmetric Newtonian stellar clusters with anisotropic distribution functions. ... Models of spherically symmetric relativistic stellar clusters with anisotropic distribution functions in relativistic regime are described by using Maxwellian distribution function with energy...

The radial distribution of metallicity of star-forming galaxies in a galaxy cluster can inform us about the mass assembly and enrichment history of the galaxy cluster. ... Both galaxy clusters are cool-core clusters at redshift z т?? ... The gas-phase metallicity of star- forming galaxies in MACS1115+01 exhibit anti-correlation with projected distance т??0.15 ТБ 0.08 dex/Mpc, whereas the radial metallicity distribution of RXJ1532+30 is statistically flat (т??0.09 ТБ 0.12 dex/Mpc). ...

... 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", . ...

... Subject and Problems of Stellar Astronomy. ... Plane of Galaxy, Methods of Its Location Determination. ... Stars Distances. ... Other Methods of Stars Distances Determination. ... Tangential Velocities, Their Determination by Self-Motions. ... Determination of Solar Apex and Spatial Velocity by Radial and Spatial Velocities of Stars. ... Features of Orientation and Parameters of Peculiar Stellar Velocities Ellipsoid. ... General and Selective Light Absorption in Galaxy. ... Darc Clouds in Galaxy. ...

... Over the first 4 years, its X-ray telescopes eROSITA and ART-XC will survey the whole sky with a record sensitivity in the 0.5-10 keV energy band. ... The goal of the second international Spectrum-RG conference is to discuss the different scientific topics addressed by the mission, synergies with surveys at other wavelengths, and requirements to follow-up observations.Contributed talks and poster presentations are invited on the topics related to the SRG science goals. ... Active galactic nuclei . ...

Next: SMUDGES Up: Minutes of the 1st Previous: Pilot Survey . ... The Jodrell Virgo survey is part of HIJASS and encompasses 4 X 8 degrees, fully sampled. ... This indicates that we should perhaps survey the outskirts of the cluster to look for low mass clouds. In the survey, objects were detected using a combination of by-eye method and automated routine. 28 detections of well known galaxies . ... Velocity distribution suggests infall or extension along the line of sight. ... Jon . ...

... Compact Binaries . ... Globular Clusters . ... Ultra-Compact binaries in globular clusters . ... It is known that UC X-ray binaries are more abundant in globular clusters compared to that found in Galactic fields (eg van der Sluys, Verbunt \ Pols 2005 and references therein). On the other hand no AM CVn systems have been found in globular clusters, while 20 are known in the Galactic field (for a review of AM CVn systems see Nelemans 2005). ...

... 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 ...

XMM-Newton CCF Release Note XMM-CCF-REL-192 EPIC MOS response S.F. Sembay, R.D. Saxton 19 August 2005 1 CCF components Name of CCF VALDATE EVALDATE Blocks changed XSCS ag EMOS1 REDIST 0057.CCF 2001-11-25 2002-05-01 CCD REDISTRIBUTION-n NO EMOS1 REDIST 0058.CCF 2002-05-01 2002-11-07 CCD REDISTRIBUTION-n NO EMOS1 REDIST 0059.CCF 2002-11-07 2004-01-01 CCD REDISTRIBUTION-n NO EMOS1 ... A core region centred on a point between the two boresights where EPIC-pn and RGS are prime. ...

... In 1930, Trumpler noticed that linear diameters (LD) of open clusters increase with distance (D) from the Sun. ... Since that time, the interstellar absorption has become one of the best studied factor in astrophysics, and we may hope that current OCL distance scales are free from this LD-D correlation. To verify if this is the case we have chosen several modern OCL distance scales and test them with the same clusters and the same angular diameters that Trumpler had used back in 1930. ...

... 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. ...

Next: Star Formation Rate and Up: No Title Previous: Calculation of Evolutionary Tracks . To start calculations, we choose the distributions of the initial binary parameters: the mass of the primary ZAMS component, , binary mass ratio, , orbital separation a . ... whereas the mass ratio distribution is not. ... The zero assumption often made is that the mass ratio distribution has a flat shape, that is binaries with a high mass ratio occur as frequently as those with equal masses. ...

... 145Slee,Roy Savage We present detailed radio and optical parameters for the stronger radio sources in 58 Abell cluster fields observed with the Very Large Array (VLA) using scaled arrays at 1.5 and 4.9 GHz. ... The cluster fields were distributed over 24 h of RA and between declinations +35 deg and -30 deg. ... Optical identifications Cluster Source Radio Centroid Optical Position EF Ang. ...