... It is reasonable to expect a priori that the evolution of events is strongly time dependent, so the star formation history in a galaxy is another important parameter. Therefore, by calculating the evolution of events after a -function like star formation burst,   one gets a Green function for any arbitrary star formation history. ... The source evolution in a galaxy with given star formation rate is thus calculated as . ...

One possible way for spiral galaxies to internally evolve would be for gas to flow to the center and form stars in a central disk (pseudo-bulge). ... In this paper we present radial profiles of stellar and 8 ЮМm emission from polycyclic aromatic hydrocarbons (PAHs) for 11 spiral galaxies to investigate whether the interstellar medium in these galaxies contains a central concentration above that expected from the exponential disk. ...

Next: Spectral observations and data Up: The Hamburg/SAO Survey for Previous: The Hamburg/SAO Survey for . ... The basic outline of the HSS and first results are described in Paper I (Ugryumov et al. [ 1999 ]), while additional results from follow-up spectroscopy are given in papers II, III and IV (Pustilnik et al. ... Next: Spectral observations and data Up: The Hamburg/SAO Survey for Previous: The Hamburg/SAO Survey for Laboratory "Structure" . ...

... FTP access the basic models is here . ... Below, we put short descriptions of the used SED models for the photometric redshifts providing by the current server . ... The uniqueness of this model consists in expanding to the near IR (NIR) of Rocca-Volmerange and Guiderdoni's (1988) atlas of synthetic spectra with a revised stellar library, which includes parameters of cool stars. ... Homepage of the GISSEL model). ... Another model used earlier is the model of synthetic spectra of Poggianti (1997). ...

There are still many open questions on galaxy formation and evolution, such as e.g. the predominance of hierarchical or monolithic processes in the galaxy formation or the temporal evolution of disk metallicity gradients. ... Chemical abundances of stellar populations of different ages are essential to constrain the past history of nearby galaxies, both in terms of their past metal contents and of SFHs. ...

... 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...

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 ...

Scale-heights of the Galactic disk subsytems with different ages and metallicities . V.Marsakov & Yu. ... It is based on the fact, that all stars cross the disk plane several times during their Galactic orbital period. ... We have used our representative sample of nearby disk F2-G2 stars Marsakov & Shevelev (1995) in which fundamental stellar parameters was determined on the basis of published date on uvby-photometry, proper motion and radial velocities. ... Marsakov V.A., Shevelev Yu.G. Bull. ...

... It is reasonable to expect that UV part of the irradiating spectrum is most influenced by the grain evolution (growth and sedimentation ) which marks the very initial stage of planet formation. 2 log J [erg s­1 cm­2] 1 0 -1 -2 -3 1000 BB 40 0 0 (A5 ) BB 20 0 00 (A5) Drai ne (A5 ) BP Ta u (A5) BB 40 0 0 (GS) BB 20 0 00 (GS) Drai ne (GS) BP Ta u (GS) Disk Model Density distribution is based on a 1+1D disk ... Green lines are used for a model with dust growth and sedimentation. ...

... 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. ...

... 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. ...

... 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" . ...

... The Network Time Protocol (NTP) is used to synchronize the time of a computer client or server to another server or reference time source, such as a radio or satellite receiver or modem. ... Information on the NTP architecture, protocol and algorithms can be found in the Further Information and Bibliography page. The Building and Installing the Distribution page presents an overview of the procedures for compiling the distribution and installing it on a typical client or server. ...

... Programme . ... Abstract: Globular clusters can probe the formation history of galaxies by providing evidence for the chemical evolution and major episodes of star formation in their host galaxies, by examining their kinematic signatures, as well as their structural parameters. ... The giant elliptical NGC 5128 (Centaurus A), at a mere 4 Mpc away, gives us the only opportunity to study in extensive detail the globular cluster system of a recent merger galaxy. ...

... 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. ...

... In brief: the frequency-dependent radiative transfer equation is solved for a dust under assumption of spherically-symmetric geometry for its distribution taking into account particle size distribution and quantum heating effects for the very small dust particles. ... Table: Model parameters for IRAS04296+3429. ... parameter . ... hot dust shell) . ... The best fit to the spectral energy distribution of IRAS04296 is shown by heavy solid line (see Table2 for details concerning parameters of the model...

spaceweb@oulu.fi - last update: 28 May 1995, 0800 UT . Advanced plasma theories are extremely important when one tries to explain, for example, the various waves and instabilities found in the plasma environment. ... In the kinetic theory it is necessary to know only the distribution function for the system of particles. ... The dependence of the distribution function on the independent variables r , v , and t is governed by an equation known as the Boltzmann equation . ... Hot plasma theory . ...

... Gomez, J. C., Athanassoula, L., Fuentes, O., & Bosma, A. 2003, in ASP Conf. ... In this work we present Evolution Strategies (ES) as an efficient method to approximate the initial conditions of the main interacting group of three galaxies in M81. ... In this first attempt we use non-self-gravitating simulations to approximate the initial conditions; even with that restriction our method reproduces the density distribution of the three galaxies with great precision. ...

XMM-Newton CCF Release Note XMM-CCF-REL-183 EPIC-pn spectral response R. D. Saxton 11 November 2004 1 CCF components Name of CCF VALDATE Blocks changed XSCS ag EPN QUANTUMEF 0015.CCF 2000-01-01 FRACTION CHANNEL, FRACTION ENERGY QE TOTAL, EBINS FRACTION NO EPN REDIST 0009.CCF 2000-01-01 NOISE PARAMS, PARTEVENT PARAMS THRESH LOSS NO 2 Changes Recent calibration work has shown that the Epic-pn redistribution function is in practice narrower than that represented in the current matrices. ...

It is a matter of common knowledge that in processes of genesis and evolution of many solar phenomena participate magnetic fields of sunspots. ... As a basis for formation of the database we take data on magnetic fields, collected by set of observatories during many years of observations. ... Section "Magnetic field data" contains data of magnetic field observation for separate sunspots, presented in standard text format (ASCII). ... Description of structure of these files is presented here . ...