Highlights - Volume 490-3 (November II 2008)

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HIGHLIGHTS: this week in A&A

Volume 490-3 (November II 2008)


In section 1. Letters

“First 450 μm dust continuum mapping of the massive star-forming region NGC 3576 with the P-ArTeMiS bolometer camera”, by P. André et al., A&A 490, p. L27

The mechanics of the formation of massive stars (more than 10 solar masses) is a matter of much debate, in part due to the distance and the complexity of the regions where massive star formation is observed. This study by André et al. of the southern high-mass star-forming region NGC3576 is an important step forward in this regard, both as a forerunner for future ALMA studies and in its own right. 


In section 6. Interstellar and circumstellar matter

“Separation of anomalous and synchrotron emissions using WMAP polarization data”, by M.-A. Miville-Deschênes et al., A&A 490, p. 1093

Understanding the cosmic background, as observed by WMAP and to be observed by PLANCK, involves understanding the diffuse emission of our own galaxy at cm and mm wavelengths. One does this by observing the spectrum, but also by using other indicators such as polarization, as discussed in this article by Miville-Deschênes et al. This allows them to separate contributions due to synchrotron emission and other processes such as rotating dust grains. 


In section 1. Letters

“Methane clathrate hydrate FTIR spectrum. Implication for its cometary and planetary detection”, by E. Dartois and D. Deboffle, A&A 490, p. L19

The identification of the infrared features associated with interstellar and cometary grains is a considerable challenge, and often it is impossible to do anything more than reach very broad conclusions. There are exceptions to this rule and one may be the methane clathrates discussed by Dartois and Deboffle in this article. They find, in fact, that one may have at low temperature somewhat akin to a gas-phase spectrum allowing a relatively precise identification of the clathrate.  
In section 8. Stellar atmospheres

“Absorption features in the spectra of X-ray bursting neutron stars”, by T. Rauch, V. Suleimanov, K. Werner, A&A 490, p. 1127

This article shows that the proper treatment of an atmosphere for a bursting neutron star can be used to determine the radius of the star, hence using a variety of equations of state the mass. In this case, a proper treatment of the line formation produces a change in the identification of the relevant lines and, through revision of the redshift, places stronger constraints on the EOS.  


© Astronomy & Astrophysics 2008