Highlights - Volume 475-2 (November IV 2007)

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HIGHLIGHTS: this week in A&A

Volume 475-2 (November IV 2007)


In section 7. Structure and stellar evolution

“Hydrodynamic simulations of irradiated secondaries in dwarf novae”, by M. Viallet and J.M. Hameury, A&A 475, p. 597

This is a detailed study of the effects of illumination on a extrasolar planetary atmosphere. The technique is very close to what is now used for modeling planets in the solar system and, among those calculations published so far, probably the closest to the meteorology that is now available.  


In section 5. Galactic structure, stellar clusters, and populations

“The Geneva-Copenhagen survey of the solar neighbourhood. II. New uvby calibrations and rediscussion of stellar ages, the G dwarf problem, age-metallicity diagram, and heating mechanisms of the disk”, by J. Holmberg, B. Nordström, and J. Andersen, A&A 475, p. 519

This paper is the second in the series on the Geneva-Copenhagen (GC) survey. This is the definitive test of the statistical uncertainties and biases for the sample presented in Paper I. It explores the sources of biases and statistical uncertainties that affect the global properties, such as the age-metallicity relation and radial metallicity gradients. The estimation of the ages of stars has been reduced by the new calibrations by about 10%, but the overall conclusions remain, making this the definitive sample of dynamics and stellar properties.  
In section 12. Atomic, molecular, and nuclear data

“Electron-impact excitation of Fe II. Collision strengths and effective collision strengths for low-lying fine-structure forbidden transitions”, by C.A. Ramsbottom, C.E. Hudson, P.H. Norrington, and M.P. Scott, A&A 475, p. 765

This paper reports very extensive calculations of effective collision strengths for the electron-impact excitation of Fe II for low-lying forbidden transitions in the lowest 16 fine-structure levels. These calculations provide the most extensive and accurate set of collisional data currently available for Fe II.  


© Astronomy & Astrophysics 2007