Next: Extinction efficiencies: general behaviour Up: Optical properties of cosmic Previous: Optical properties of cosmic . It is now evident that observed interstellar extinction cannot be explain using particles of only one kind. ... The intensity of radiation after passing a dust cloud is equal to . ... The interstellar extinction is . ... Next: Extinction efficiencies: general behaviour Up: Optical properties of cosmic Previous: Optical properties of cosmic root 2003-04-09 ...

We investigate the far-infrared (IR) dust emission for 20 local star forming galaxies from the Key Insights on Nearby Galaxies: A Far-IR Survey with Herschel (KINGFISH) sample. ... Our fitting method allows us to investigate the resolved nature of temperature and emissivity variations by modeling from the galaxy centers to the outskirts (physical scales of ~15-50 kpc, depending on the size of the galaxy). ...

Next: EVOLUTION MODELS Up: EXTREME HELIUM STARS: PULSATION Previous: EXTREME HELIUM STARS . The characteristic surface properties, effective temperature , surface gravity and composition , of EHes have been summarized by Jeffery (1996). ... Helium: ( ) By definition, helium dominates the atmospheric abundances. ... This is supported by a correlation between N and Fe abundances in EHes. ... Next: EVOLUTION MODELS Up: EXTREME HELIUM STARS: PULSATION Previous: EXTREME HELIUM STARS Simon Jeffery . ...

... 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. ...

Next: Redshift Distribution Up: Sample Identification Previous: Previously Identified Sources . ... In Figure 3, we plot the redshift distribution of DXRBS FSRQs opposite that of the 1 Jy and S4 samples. In Figure 4, we plot the redshift distribution of DXRBS BL Lacs opposite the Slew and 1 Jy samples. ... The apparent deficit of objects at the very highest luminosities is a result of the smaller area of sky covered by DXRBS compared to, e.g., the Slew and 1 Jy samples. ...

... The Science Operation Department is composed of Astronomers, Telescope Instruments Operators(TIOs) and Data Handling Administrators(DHAs). ... Astronomers have proposed several methods to quantitatively measure the amount of turbulence above the telescope, which the most common ones is Differential Image Motion Monitor (DIMM). In optical testing, the Hartmann test is the common method to test the quality of optical components. ... Hartmann mask consists of 48 lenses. ...