... Bruce MacA Thomas 11 February 1999 Introduction In this discussion document, the antenna principles underpinning some of the concepts discussed in Ref 1 for the LF-SKA are extended to illustrate the potential difficulty of achieving constant collecting area, and hence the practical realisation of the "magic-carpet" concept. Applications to the "randomised" antenna-element approach to array-station design, and the trade-offs that need to be considered, are briefly discussed. ...

Participant 3 (P3) ================== Prof. N.V . Voshchinnikov - Astronomy Department and Sobolev Astronomical Institute, St. Petersburg University, RU Dr. V.B. Il'in - Sobolev Astronomical Institute, St. Petersburg University, RU M.S. Prokop'eva - 24 years old; Astronomy Department, St. Petersburg University, RU D.A. Semenov - 22 years old; Astronomy Department, St. Petersburg University, RU The head of the team, Prof ... Astrophys. ... Transfer, v. 63, 205, 1999). ...

... scattered light in flats less than 0.5% across 5' field of view . scattered light in flats less than 0.5% across entire field . ... no greater than 10% across field, and calibrateable to better than 1%. no greater than 5% across field, and calibrateable to better than 0.5%. ... provide unvignetted illumination across detector with new SDSS filter set . ... throughput stable to better than 0.5% over course of a night. throughput stable to better than 5% over thermal cycling and seasonal variation . ...

... 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...

... spectrum . ... The photons we detect originate in the outermost layers, or atmosphere, of the star. In order to interpret stellar spectra, it is necessary to construct models which accurately represent the structure of a stellar atmosphere and the transfer of radiation from the stellar interior into interstellar space. For the study of helium stars and other stellar remnants, we in Armagh use several computer programs, of which sterne and spectrum are the most important. sterne . ...

The fact charged particles circle around field lines was well known to J.J. Thomson when he experimented with electron and ion beams in a magnetic field. ... The notion of adiabatic invariance is tied with the early years of quantum theory. ... By the rules of conventional physics, atoms were expected to continually lose energy, yet the absorption and emission of light suggested that they could exist in certain stable states where their energy was fixed. ...

... As part of our effort to enhance the calibration of STIS (a spectrograph on-board the Hubble Space Telescope), we have developed a model of the readout process for CCD detectors suffering from degraded charge transfer efficiency. ... Nevertheless the empirical corrections for STIS provide an ideal means of testing and calibrating the physical model, as the empirical corrections are essentially a distillation of what is to be learnt from the calibration data with respect to CTI. ...

At the undergraduate level, I teach mostly engineering science courses in the areas of thermodynamics and fluid mechanics. ... In conjunction with heat transfer, they constitute the basis for such applications as heat exchangers, air conditioning, aerodynamics, turbomachinery, pipe flows, energy conversion, and others. ... Have the students use and develop fundamental analytical skills in the specific context of the course. ... o MEE 341 : Fluid Mechanics I . o MEE 342 : Fluid Mechanics II . ...

The Archeops experiment aimed at measuring the cosmic background emitted just after the Big Bang. The study of this radiation is essential to obtain precise information on the evolution of the Universe: density, Hubble constant, age of the Universe.. To achieve this goal, measurements have been done with devices cooled down at 100mK temperature placed at the focus of a warm telescope. ... 28960 visitors . ...