Chair of solid state physics . ... The Physics of Phonons . ... In the first part of the course “The Physics of Phonons” the dynamics of atoms in one- and three- dimensional crystalline lattices is considered in detail. The quasiparticle conception in solids, taking phonons as an example, is discussed; creation and annihilation operators of phonons, main properties of acoustic and optical phonons dispersion laws, density of phonon states. ... Crystalline state. ... Acoustic and optical phonons. ...

... Table 32.2 summarizes the nominal initial accuracies for different kinds of acquisitions. ... FOS Target Acquisition Calibration Accuracies . ... ACQ . ... Blind Pointing . ... In summary, the pointing accuracy limitations of FOS target acquisition methods are: . ... ACQ/PEAK: . ... This was the value achieved by all FOS externally pointed calibration observations obtained after July 1, 1992 and was the ultimate limiting positional accuracy of FOS photocathode granularity and sensitivity calibration...

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... Using the central limit theorem, the total noise can be approximated by a Gaussian or normal distribution which has the frequency function : . ... where is the mean intensity of the source. ... In the statistical analysis of the probability distribution of data several estimators based on moments are used. ... For a normal distribution, these moments are and while for a Poisson distribution are and . Besides these moments other estimators are used to describe a distribution e.g. median and mode . ...

Spectrum Management and RFI activity at AO ------------------------------------------ With the recent explosion in global communication systems, and the ever-increasing usage of the radio spectrum in Puerto Rico, spectrum management activities at Arecibo Observatory are becoming both complex and multidimensional. ... In these bands, observations can only be carried out either by utilizing RFI-excision techniques or in a coordinated manner with other users (D). ...

... It is notoriously difficult to identify weak cosmic ray events in long exposure observations. ... The method is to compare the probability distribution function (PDF) of cosmic ray events between an observation and a dark frame matched in exposure time. We illustrate the basic idea using dark exposures from a Tek 1024 1024 CCD with varying exposure lengths and read-out times. ... Figure: Histogram of cosmic ray events in a two hour dark frame. ... Original PostScript figure (78 kB) . ...

... Status of the numerical solutions and validation 2. ... Coupling of "solid" Earth components, e.g. core ­ mantle (Dehant et al.) ... Consistent relativistic formulation of Earth rotation (Gerlach, Klioner, Soffel) Status of the numerical solutions - 2 · The results from numerical solutions suffer from ­ Simplified solid Earth models ­ Incomplete Earth system models or neglecting of certain parts or neglecting of certain coupling mechanisms ­ Methodological limitations of computations...

Next: SAS processing Up: Maintenance procedures Previous: Maintenance procedures Contents . Suitable observations should be longer than about 20 ksec, cover all the considered time period, and have different background levels, in particular the highest ones, so the sample should include observations taken at the beginning and end of the science window. It is helpful to consider objects for which no RGS spectrum is expected or to look at the RGS monitor pages. ... Michael Smith 2011-09-20 ...

... The most precisely determined characteristic for accreting neutron stars (NS's) is their period. ... Period changes show fluctuations. ... Some applications of stochastic processes in astrophysics especially in accreting systems were discussed in Lipunov (1987),Hoshino Takeshima (1993) and Lipunov (1992).In Hoshino Takeshima (1993) the authors, using simple models of MHD turbulence, try to explain aperiodic changes in X-ray luminosity of X-ray pulsars. ... Here, -constant angular momentum. ...

Next: Some theory Up: userhtml Previous: Calibration . By many measures, the ATCA 3-mm observing band is a completely different domain to the other ATCA bands. ... Not surprisingly many aspects of the data reduction are also different. This chapter reviews the theory behind some of the differences, and then considers a practical approach to calibration. ... Antenna gain considerations and flux calibration . Instrumental phase . Atmospheric phase and phase calibration considerations . ...

... The dayside auroral precipitation consist of magnetosheath related boundary layer precipitation, and plasma sheet related BPS/CPS precipitation (extensions of the nightside precipitation regions). ... For example, the much lower fluxes from the LLBL region when compared to the cusp are compensated by the bidirectional electron beams found in the LLBL: the precipitating energy fluxes in the LLBL and the cusp are not that different. ... directly through the cusp and plasma mantle . ...

A very important stage in a story of formation of any new science is the shift from discussion of situation which are possible but do not occur in practice due to some reason to recognition of real phenomena of interest. ... We suggest to consider computer viruses as this new specific form of life which is coming in the contact with our form of life. ... Computer life has been created by human being, the role of independent evolution of computer viruses seems to be still negligible. ...

... Archives . ... Speaking of XAtlas from my previous post I tried another visualization tool called Parallel Coordinates on these Capella observations and two stars with multiple observations (AL Lac and IM Peg). ... Algorithms arXiv Astro Bad AstroStat Bayesian CHASC Cross-Cultural Data Processing Fitting Frequentist Galaxies gamma-ray High-Energy Imaging Jargon Job Languages MC MCMC Meta Methods Misc News Nuggets Objects Optical Physics Quotes Spectral Stars Stat Timing Uncertainty X-ray . ...

Teaching courses . for student of the Department of Astrophysics and Stellar Astronomy . ... Geophysics and physics of the planets (Kurt, Panteleev) . ... Close Binary Stars . ... Solar Physics . ... This is introductory course for students of the third year of education which are familiar with elementary astronomy and general physics. ... The one-year course includes theory of radiation transfer, theory of internal stellar structure with account of binary systems with compact comapnions. ...

Next: The Chemical Evolution of Up: Stellar Astrophysics Previous: Stellar Astrophysics . Simon Jeffery has used a novel camera attached to the William Herschel Telescope (WHT) to obtain the best light curves ever obtained for pulsating subdwarf B stars. These stars pulsate non-radially in several modes with different frequencies and enable astronomers to establish their overall properties and internal structure with unusual precision. ...

... In Samara State Aerospace University will establish development and manufacture of electronic and optoelectronic components for the space industry. ... SSAU held a meeting on the development of the centre of microelectronics for the aerospace industry. It was attended by the representatives of the University, the Ministry of Economic Development, Investments and Trade of Samara Region, Russian engineering company ELTEKH and the Swiss Centre for Electronics and Microtechnology CSEM 1 . ...

Atmospheric influence on the different radio-engineering system functioning . ESTIMATION OF ATMOSPHERIC OPTICAL CHARACTERISTICS AND REMOTELY SANSED IMAGE CORRECTION . ... Direct transmittance estimation results for 12 channels of the spectrometer CHRIS. ... We have managed to develop a direct method of estimating the discrete Normalized Atmospheric Point Spread Function (NAPSF) from available images alone, not using any external sources of information about the atmosphere. ... IRE RAS 1996-20 11 ...

... The department was founded in late sixties by Prof. D.Ya.Martynov, who for many years was also the director of Sternberg Astronomical Institute. At present time, the head of the department is Prof. A.M.Cherepashchuk, a pupil of D.Ya.Martynov and his successor as the director of SAI. Since Prof. Martynov, the scientific activity of the department was primarily related to binary stars. ... The department consists of 15 members most of which have Ph.D. in Astrophysics. ...

The efficiency of interaction of radiation with a particle and hence its optical properties depend on the particle chemical composition, size, shape, structure, etc. ... Particle size expressed in units of the wavelength of incident radiation, together with chemical composition, most strongly affects the optical properties of a scatterer. ... There are many methods to solve the light-scattering problem for a homogeneous spheroid (our survey of the light-scattering methods see here ). ...

Nowadays at the Department the experimental and theoretical investigations, including astronomical and ionospheric observations, active experiments with space vehicles are taking place. ... Solar Corona physics and erruptive phenomenae. ... Stellar astronomy. ... The Department has organized and put into practice more then 50 expeditions for observation of Solar ecllipces, aurorae polaris, comets, meteor streams, controlled space experiments, and also for investigations of geophysical characteristics. ...