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. ...

Close binary systems of the RS CVn and Algol type are characterized by a highly variable radio emission, from typical flux densities of a few mJy during low-activity (quiescent) periods, up to 1 Jy during strong flares. The origin of this radio emission is attributed to the gyrosynchrotron mechanism. Several observations of these stars have shown an evolution of the radio spectrum during both the rising and decay phases of flares. ...

... 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. ...

... 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 . ...

Dwarf novae are a subclass of cataclysmic variable stars in which a late-type secondary fills its Roche lobe and transfers mass to a white dwarf primary via an accretion disc. ... Those spiral structures are very similar to the spiral shocks discovered by Sawada, Matsuda & Hachisu (1986) in 2D finite difference numerical simulations in accretion discs. In this poster, we want to compare 2D numerical simulations of accretion disc with the observations of SH2 . ...

Next: MASSES Up: EXTREME HELIUM STARS: PULSATION Previous: STELLAR PROPERTIES . ... Following main-sequence evolution, a red giant star in a close binary system may expand to fill its Roche lobe. ... Although Iben & Tutukov (1984) used this model to account for the EHes, the latter are not binaries (Jeffery et al. ... Final helium-shell flash in a post-AGB star. ... Accretion from the disk onto the surviving WD creates a star with a degenerate CO core and a helium envelope. ... Other models. ...

... Keywords: globular clusters,M3,photometry,HST . ... Perform the most accurate test of the ``stellar clock'' used in dating globular clusters. ... These data will provide the first complete sample of post-main sequence stars over the entire area of the cluster, and will allow the most stringent tests of stellar evolution and dynamics models. ... M3 contains the largest population of Blue Straggler Stars (BSS) detected in a globular cluster so far ( ). ...

... Australia Telescope Steering Committee . ... Parkes radio telescope . ... Late Stages of Stellar Evolution . Welcome to the home page of the Late Stages of Stellar Evolution" We are a research group which operates within the Astrophysics Group of the Australia Telescope National Facility. ... To investigate the late stages of stellar evolution and in particular the role of stellar mass-loss in the evolution of asymptotic giant branch stars, proto-planetary nebulae and extremely massive stars. ...

... Galaxy Evolution home . ... Regulating the ISM and star formation . Cosmological evolution of star-forming galaxies . The origin and evolution of radio sources . Radio sources and their environments . ... Observations of the local Universe clearly demonstrate that very active star formation phases (starbursts) are often associated with interacting and merging galaxies and that in these systems much of the short wavelength emission is absorbed by dust and re-emitted in the IR. ...

Chiaki Kobayashi, Ralph Sutherland How galaxies did form and evolution? - to answer this unsolved problem, we are simulating the formation and evolutionary history of galaxies in the Universe, including star formation, supernovae feedback, and chemical enrichment. Comparing the spacial distribution of elements within galaxies with observations, we will examine fundamental physical processes that drive galaxy formation. ... COALA : Universe Galaxy AGN Star Planet ...

... We focus on the mass loss that stars experience along the way to their final stage as white dwarfs Evolution of a Sun-like Star 1. ... 2009): M WD = 0.339 + 0.129M Fit the clusters using both sets of models and a linear IFMR ages 95% Posterior Intervals (M Sun Simulated: Yi Fit: Yi 8 Simulated: Dotter Fit: Yi Simulated: Yi Fit: Dotter ) 6 logAge 4 8.4 8.6 8.8 9.0 9.1 9.2 9.4 9.6 2 2 4 6 8 Sun 2 4 6 8 Sun 2 4 6 8 Sun True Initial Mass (M ) True Initial Mass (M ) True Initial ...

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. ...

Role in the Universe IAU Symposium 209, 2002 M. Dopita, S. Kwok and R.S. Sutherland, eds. Near-infrared monitoring of the carbon star IRC +10 216 : A high spatial-resolution time sequence of dust -shell evolution G. Weigelt , T. Blocker, K.-H. Hofmann, A. Men'shchikov, J.M. Winters Max{Planck{Institut fur Radioastronomie, 53121 Bonn, Germany Y. Balega Special Astrophysical Observatory, Nizhnij Arkhyz, 35147, Russia The carbon star IRC +10 ... 2000, Tuthill et al. 2000). ...

... We publish 16 Doppler imaging temperature maps for the years 1994-2002 of the active RS CVn star II Peg. ... Through Doppler imaging we want to study the spot evolution of the star and in particular compare this with previous results showing a cyclic spot behaviour and persistent active longitudes. ... The derived temperature maps are quite similar to the ones obtained earlier with a different methods, the main differences occurring in the spot latitudes and relative strength of the spot structures....

... Астронет | ... планета Астронет | ... An investigation of the structure of non-uniformities of interstellar absorption using photometry of globular clusters . ... L. N. Berdnikov; D. G. Turner . A search for evolutionary changes in the periods of Cepheids using archival data from the Harvard observatory plate collection I: VY, WZ and GH Carinae . ... Study of changes in the periods of population II Cepheids in globular clusters I: M2 . ... A. O. Allakhverdiev; S. O. Tagiyeva; O. H. Guseinov . ...

GRANAT is the Russian x-ray sattelite launched to the high apogee orbit (200,000 km) and operated almost for 10 years (1989 -1999) , carrying out four major instruments: French SIGMA coded-mask hard x-ray telescope (30-1000 keV), Soviet ART-P coded-mask telescope (2??-60?? keV), all-sky monitor WATCH (6-150 keV), and a gamma-burst detector PHEBUS . ... Since September 1994, GRANAT is in the survey mode. ... Explore pages devoted to individual GRANAT instruments (including main scientific results): . ...

Irregular phenomena in the Earth Pole oscillation process and temporal variations of geopotential Valery Bondarenko, Vadim Perepelkin s The observed irregular phenomena in the Earth Pole oscillation process are very variety. ... These phenomena indicated in the IERS data are the "abnormal" fluctuation of the Earth Pole coordinates which owing to changing of the geodynamical parameters gives negative result in interpolation and forecast of the first approximation mathematical model. ... Fig. ...

Proposal Identi cation No.: A1218 Date Received: 1998-Nov- 1 23:05:09 Technical Page Proposal Type: Regular General Category: Astronomy Sub-Category: Spectroscopy Observation Category: Extragalactic Total Time Requested: 36 Hours Proposal Title: HI Evolution in Intermediate Redshift Galaxy Clusters ABSTRACT: We propose to use do test observations of the HI component of 26 intermediate redshift galaxy clusters. ... Maybe Part of the observing run. ...

... LMC Project Outline . NGC 1818 Initial Results . ... The Large Magellanic Cloud (LMC) is uniquely suitable for the study of massive star clusters at all stages of evolution. By combining HST observations of these clusters with N-body models we hope to understand the origin and evolution of rich star clusters in our own Galaxy, in the LMC, and beyond. ... We aim to combine our HST observations with N-body models to understand the formation and evolution of globular clusters. ...

... 8, ``Celestial Mechanics'', 2002 Dynamic evolution of resonance orbits of exoplanets in system 47 Uma B. R. Mushailov, A. A. Kaloshin Sternberg Astronomical Institute, Moscow, Russia The orbits of the major and minor planets of the Solar system indicate that their dynamic evolution is essentially influenced by the effects of orbital reso­ nance interactions. ... One may expect that the orbital resonances can exist not only in the Solar system, but also in other star systems. ...