Subject, Problems and Objects of Theoretical Astrophysics. ... Stellar Photospheres, Their Features. ... Physics of Continuous Radiation Absorption in Stellar Photospheres. ... Continuous Radiation Absorption in Stellar Photospheres of Various Spectral Classes. Solar Type Photospheres. ... Characterisics of Absorption Lines. ... Interstellar Absorption Lines, Their Features. ... Physical and Dynamic Features of Interstellar Medium, Which Follows from Observations of Interstellar Absorption Lines. ...

... In the first page of this chapter, Eddington computes an effective temperature of 3.18 K, but this has nothing to do with the 2.725 K blackbody spectrum of the Cosmic Microwave Background (CMB) . Here is a quote of what Eddington actually said: . ... We shall first calculate the energy density of this radiation. ... It is clear that Eddington's model fits the optical data, but that Eddington did not anticipate either the CMB (red curve) or the interstellar dust (ISD, green curve). ...

... Luminosity (L) · · · · A source's luminosity is the power that it emits in radiation. ... NB Astronomers often say `flux' when they mean `flux density' · SI units are Wm-2Hz -1 -26 filter · Also used are Jy 10 Wm-2Hz -1 E= РРРF d dA dt Specific Intensity, Surface Brightness (I) · Specific intensity (or surface brightness) is the power received (or emitted) per unit area per unit frequency per unit solid angle. ч F at surface of a spherical source = I · · Specific intensity is independent of distance...

... About ATNF overview . ... Parkes radio telescope . ... Saxton & Wu (1999) presented calculations of the stability of the accretion shock which forms on the surface of an accreting magnetic white dwarf in AM Herculis type systems in an attempt to explain the observed properties of the quasi periodic oscillations sometimes seen in these systems. He showed that radiative cooling may cause thermal instability in the post-shock structure of the accretion flow settling onto a magnetic white dwarf. ...

A Tunable 350-780 GHz CW Solid State Oscillator of Intrinsic Josephson Junctions in a high-Tc Superconductor H. B. Wang#,*, M. Y. Li#,*, J. Yuan#, N. Kinevy, J. Li#, B. Grossz, S. Guenonz, A. Ishii# ... Quantum Phenomena in LISA+, Universitaet Tuebingen, D-72076 Tuebingen, Germany Email: hbwang1000@gmail.com Abstract--We report on THz emission measurements and low temperature scanning laser imaging of Bi2Sr2CaCu2O8 intrinsic ...

... We present a computer program for modelling energy flux distribution and light curves of eclipsing binaries from far ultraviolet to infrared regions. The Roche model is assumed. Proximity effects of components (reflection of radiation and surface gravity darkening) are taken into account. ... Figure 1: The surface temperature distribution for Algol A-B system before (upper plot) and after (lower plot) correction for temperature due to the irradiation effect. ...

The sband wide receiver has resonances in the OMT. ... A simplified model of the system temperature including these resonances is: Tsys= Tomt*alpha + (1-alpha)*Tsky + Tamp. ... Rewriting the equation: Tsys= Tsky + Tamp + alpha*(Tomt-Tsky) Shows that the spectral density at the resonance will increase or decrease (relative to the adjacent frequencies) depending on whether or not (Tomt-Tsky) is positive or negative. ... black - spectral density on the absorber . red - spectral density on the sky . ...

... The basic principles of incoherent scatter: . ... Because of the electron movement, spectrum of the observed signal is broad and it has shape which depends, e.g., on the temperature. ... ion temperature . ... According to the theory, Ti should be replaced by (2Ti,perp + Ti,par)/3 (Williams and Jain,1986; Glatthor and Hernandez, 1990; Winser et al., 1990). ... Glatthor, N., and R. Hernandez, Temperature anisotropy of drifting ions in the auroral F-region, observed by EISCAT, J. atmos. terr. ...

Microsymposium 38, MS080, 2003 (A4 format) PHYSICAL AND MINERALOGY CHARACTERISTICS OF THE LUNAR REGOLITH IN THE AREAS OF THE THERMAL ANOMALIES. ... Comparison of the local cumulative number of particles N per 104 m2 and photometric roughness parameter I. In this report we research data of the IR thermal radiation, the rough structure of the lunar regolith and mineralogy characteristics upper layer of the surface. ... The spatial graphical function of the lunar-surface thermal radiation. ... Figure 3. ...

Physical conditions of the interstellar medium in galaxies are closely linked to the ambient radiation field and the heating of dust grains. ... The KINGFISH profiles are well suited to examining trends of dust temperature Tdust and нІ because they span a factor of ~200 in the ISRF intensity heating the bulk of the dust mass, Umin. Results from fitting the profile SEDs suggest that, on average, Tdust, dust optical depth о„dust, and Umin decrease with radius. ...

... Yu.A.Nefyodov, M.R.Trunin, A.F.Shevchun, D.V.Shovkun, N.N.Kolesnikov, M.P.Kulakov, A.Agliolo Gallitto, and S.Fricano, Europhysics Letters 58 (3), 422 (2002) . ... M.R. Trunin, Yu.A. Nefyodov, A.F. Shevchun Phys. Rev. Lett. 92 , 067006 (2004) . ... M.R. Trunin, Yu.A. Nefyodov, A.F. Shevchun, Supercond.Sci. ... V.N. Egorov, V.L. Masalov, Yu.A. Nefyodov, A.F. Shevchun, M.R. Trunin, V.E. Zhitomirsky, and M. McLean. ... Yu.A. Nefyodov, A.F. Shevchun, A.M. Shuvaev, M.R. Trunin . ... Publications . ...

... Solar flare activity is produced by the processes of accumulation and release of energy in an active region. ... In the framework of study of solar active regions, producing powerful flares the researchers from the RATAN-600 radio telescope have detected sources with features in the form of a sharp drop in the intensity of polarized radiation in various parts of the recorded frequency range (2-16GHz), sometimes changing the sign of polarization. ...

... In this section, we develop a physical model of the secondary as a disk that is centrifugally supported in the radial direction and hydrostatically supported in the vertical direction. We assume that the disk is vertically isothermal and well mixed. ... where is the mean molecular mass of the gas, is the orbital period at the outer edge of the disk in years, and all of the mass of the secondary has been assumed to be concentrated near its center, so the Keplerian approximation is valid. ...

XMM-Newton Science Analysis System . ... These subroutines calculate the power (in watts) radiated per unit surface area (m2) per unit solid angle (sr) by a black body at temperature='kelvin'. The power can be calculated either per unit frequency, at a given frequency (both in hertz), or per unit wavelength (in metres) at a given supplied wavelength (in angstroms). ... Per unit frequency . Per unit wavelength . XMM-Newton SOC/SSC -- 2005-08-15 ...

... 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...

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... Spectrosc., 90 , 574-579. [ abstract (in English; ASCII file); paper (in Russian; PS file)] . ... Astronomy Letters, 26 , N 10, 679-690. [ abstract (ASCII file); paper (PDF file)] . ... 2001) . ... 72 , N 5, 607-612. [ abstract (ASCII file); paper (PS file)] . ... Scattering and polarization properties of the non-spherical particles. in: Smith W.L., Timofeyev Y.M. (eds.) IRS 2000: Current Problems in Atmospheric Radiation, A.Deepak Publ. (in press) [ abstract (ASCII file); paper (PS file)] . ...

... Calibration and sensitivity measurements for tests of microwave radiometers. ... The instrument consists of two waveguide matched loads operating at ambient temperature and two matched loads, cooled at variable temperatures. The temperatures are microprocessor-controlled. The test version of instrument is available. ... Dimensions                                          450 350 550 mm . ... Output temperature                                            100–350 й . ...

home education > activities . ... Quick math activity that asks students to calculate scale models of a binary star system with a black hole in it. [h] . ... Students use a radiometer and a light bulb with a dimmer switch to make connections between the temperature, color, and radiation output of a star. ... This demonstration, similar to the above, from the Exploratorium Snack-book of science activities, lets students demonstrate how molecules scatter light and change the colors of the beam. [m,h] . ...

Next: Anatomy of a decline Up: PHYSICAL CHARACTERISTICS Previous: Pulsations . The most obvious and spectacular properties of RCB stars are their dramatic fading events. ... Initial decline is sudden and steep, the star can fade by up to 8 magnitudes in a few weeks. ... This aspect of RCB behaviour represents an area where amateur astronomers consistently make a major contribution - particularly by alerting the research community to the onset of a fading event. ...