Highlights - Volume 481-2 (April II 2008)
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- Published on 21 March 2008
| HIGHLIGHTS: this week in A&A |
Volume 481-2 (April II 2008)
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In section 1. Letters “Indications for 3 Mpc-scale large-scale structure associated with an X-ray luminous cluster of galaxies at z=0.95”, by R. Fassbender et al., A&A 481, p. 677 Cluster of galaxies are now being discovered at redshifts that are high enough (z ~ 1) to be used as cosmological probes. This paper reports the discovery and the properties of a distant (z=0.95) X-ray selected galaxy cluster and its environment. The environment includes a likely associated second galaxy cluster and a possible optical bridge between the clusters. Such a bridge might trace the cosmic large-scale structure already in place 7.5 billion years ago. In addition, this case represents one of the rare examples in which both X-ray and optical analyses can be performed at high redshift, thus allowing a solid study of the effects of the cluster's environment on the evolution of its galaxy population. |
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| In section 6. Interstellar and circumstellar matter
“Exploring interstellar titanium and deuterium abundances and other correlations”, by R. Lallement, G. Hébrard, and B.Y. Welsh, A&A 481, p. 381 Understanding the variation in the interstellar D/H abundance ratio in the Galaxy is important because of the implications for cosmology and for galactic evolution. It has become clear over the past few years that determining this ratio is complicated by how a considerable fraction of D is depleted onto dust grains, causing many measurements to underestimate D/H. The study published in this issue confirms this idea. It shows a correlation between titanium column densities measured with UVES on the VLT and deuterium column densities. This explains the spread between D/H in different lines of sight. |
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In section 7. Stellar structure and evolution
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© Astronomy & Astrophysics 2008