... Archives . ... One of the speakers from the google talk series exemplified model based clustering and mentioned the likelihood ratio test (LRT) for defining the number of clusters. ... The LRT is worthless for testing a mixture when the set of parameters is large . ... We prove in this paper that the LRT is worthless from testing a distribution against a two components mixture when the set of parameters is large. ... Category: arXiv , Bad AstroStat , CHASC , Frequentist , Stat | Comment ( RSS ) | ...

... 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. ...

... We are exploring the use of unlabeled data for supervised classification and for semi-supervised clustering. Current automated classification methods rely heavily on supervised learning algorithms that require training data sets containing large amounts of previously classified, or labeled, data. ... Some labeled data are needed to actually classify rather than cluster the data. ... One set, l , consists of the labeled data (xi ,ci) where xi is a feature vector and ci is a class label. ...

... 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]. ...

... 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. ...

... HST . ... Lensing Models . ... In order to interpret many of the properties of background lensed galaxies, reliable models of the lensing maps for each cluster are required. Preliminary models for each of the six Frontier Fields clusters have been provided by five independent groups prior to the HST Frontier Fields observing campaign in order to facilitate rapid analysis of the FF data by all members of the community. ... The various groups model the cluster mass distribution in different ways. ...

... Commission 37: Star Clusters and Associations . Home Page . Commission 37 of the International Astronomical Union deals with all aspects of Globular Cluster, Open Cluster, and Stellar Associations research. With Commission 33 it forms Division VII of the IAU. Commission Structure . ... IAU Home Page . Open Clusters Database (maintained by J.-C. Mermilliod ) . Catalogue of Milky Way Globular Cluster Parameters (maintained by W. E. Harris ) . ...

... 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. ...

. N OTE: . Only clusters with R<60 kpc were used to compute the spatial parameters and metallicity gradients for all subsystems except the corona. The numbers in parantheses give the number of clusters for which the corresponding parameter is known. The X O scale length of the old halo is strongly distorted by the observed asymmetry of the distribution of the corresponding clusters projected onto the XY plane ( Fig. 4А ) . discussion in the text | previous table .

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 . ...

... Observatory . ... The Laboratory of Astrometry . Dept. for Physics of Stars&Galaxies . ... Astronomical Calendar . ... UkrVO . ... The purpose of research: Creating a stellar catalog to study the structure and kinematics of star systems, including open star clusters and stars with large proper motions; the enhancement ICRF / Hipparcos system to stars dawn to 17 m (V); Search of binary systems of brown dwarfs and determination of their parameters; astrometry of minor bodies of the Solar System. ...

Find Similar Abstracts (with default settings below ) . ... Also-Read Articles . ... Parameters of the 41 Dra system components . ... 00/2001 . ... Stars: Binaries, Binaries: Fundamental Parameters, Binaries: Individual . ... 61B Based on spectral and speckle-interferometric observations of the system 41 Dra, model atmosphere parameters of the system components have been derived: component Aa - T eff = 6500K, lg g = 3.99, R = 1.87 R solar , component Ab - T eff = 6500K, lg g = 4.11, R = 1.61 R solar . ...

Next: CAL_getBoresightMatrix Up: Routines of the Calibration Previous: List of CCF Components Contents . ... The CAL functions CAL_getBadPixelList & CAL_getBadPixelMap use the CAL state variable temperature only to check that the current operating temperature is consistent with the CCF constituent BadPix . ... Used CAL State Variables . List of CCF Components used . ... Next: CAL_getBoresightMatrix Up: Routines of the Calibration Previous: List of CCF Components Contents Michael Smith 2011-09-20 ...

... CentralProcessor 0.11 documentation . ... An option for continuum imaging is to run self-calibration at the same time. ... Use this parset in ccalibrator to calibrate the antenna-based gains . Re-run imaging, applying the latest gains table . ... At the end, the final gains calibration table is kept in the main output directory (as this can then be used by the spectral-line imaging pipeline). ... User Parameters - Continuum imaging . User Parameters - Mosaicking Continuum images . ...

... Contacts . 2012: . ... We refined the fundamental parameters of the components, the orbital periods, and the conditions of photospheric heating of the secondary component by the ultraviolet radiation of the hot component. ... The observations of the star clusters associated with ultra-luminous x-ray sources (ULXs) in four galaxies on the 6-meter and VLT telescopes have shown that all the ULXs are located within 200pc of very young star clusters (younger than 5 million years). ... Archive . ...

The X-ray Fundamental Plane of Clusters of Galaxies Yutaka Fujita National Astronomical Observatory, Japan We analyze the relations among central gas density, core radius, and temperature of X-ray clusters by plotting the observational data in the three-dimensional (log  gas;0 , log r c , and log T gas ) space and nd that the data lie on a 'fundamental plane'. ... The two parameters describing the plane are formation redshift and temperature of clusters. ...

... The Astronomical Society of the Pacific (ASP) presented Priscilla and Bart Bok Awards to two high School Seniors at the Intel International Science and Engineering Fair held May 10 to 15 in Reno this year. ... The Bok prize is named for Bart and Priscilla Bok. ... About 10 years ago, at the suggestion of the American Astronomical Society, the activities supported by the Bok Fund were expanded to include the joint sponsorship of an astronomy award at Intel Science and Education Fair. ...

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: Mass change Up: Evolutionary Scenarios of Binary Previous: Stellar Winds From Normal . As mentioned earlier, the duration of the binary evolutionary stage (say, I+I) is determined by the faster evolving component , where is the time each component spends at the corresponding evolutionary stage. ... Next, we should calculate the mass change for the slower evolving companion, the orbital semi-major axis and the eccentricity. Mass change . Semi-major axis change . ...

The new view on the population of Galactic open clusters A.E.Piskunov1, N.V.Kharchenko2, S.RЖser3, E.Schilbach3, R.-D.Scholz4 1 2 3 4 Institute of Astronomy, Moscow, Russia Main Astronomical ... Observatory, Kiev, Ukraine Astronomisches Rechen-Institut, Heidelberg, Germany Astrophysikalisches Institut Potsdam, Germany What are open clusters and what do they teach us Groups of Population I ... Cluster complexes: OCC-1 = Gould's Belt cluster complex? ...