ar X iv : a st ro - p h / 02 08 44 0 v 2 2 8 A ug 2 00 2 A convolution integral representation of the thermal Sunyaev - Zel ’ dovich effect

ar X iv : a st ro - p h / 02 08 44 0 v 3 2 7 Fe b 20 03 A convolution integral representation of the thermal Sunyaev - Zel ’ dovich effect

Analytical expressions for the non-relativistic and relativistic Sunyaev-Zel'dovich effect (SZE) are derived by means of suitable convolution in-tegrals. The establishment of these expressions is based on the fact that the SZE disturbed spectrum, at high frequencies, possesses the form of a Laplace transform of the single line distortion profile (structure factor). Implications of this descript...

ar X iv : a st ro - p h / 03 05 46 5 v 1 2 3 M ay 2 00 3 Sunyaev - Zel ’ dovich cluster surveys using a large beam

Sunyaev Zel’dovich cluster surveys can be used to constrain cosmological parameters. Extracting clusters from the primary anisotropies and the unresolved background from very faint clusters is simple when the telescope beam size is small (∼ 1′), but could be difficult if the beam is larger (∼ 8′). By reference to examples, we show that this is possible by carefully designing the depth of the su...

ar X iv : a st ro - p h / 97 11 13 5 v 1 1 2 N ov 1 99 7 HOT ELECTRONS AND COLD PHOTONS : GALAXY CLUSTERS AND THE SUNYAEV - ZEL ’ DOVICH EFFECT

ar X iv : a st ro - p h / 00 08 44 8 v 1 2 9 A ug 2 00 0 The Impact of Adaptive Optics on Star Formation Research

In this paper, we discuss the benefits of ground-based, adaptive optics (AO) aided observations for star formation research. After outlining the general advantages, we present results obtained during the ALFA science demonstration programme in 1999. These results underline the absolute necessity of AO assistance for almost any kind of observations regarding star formation regions.

ar X iv : a st ro - p h / 00 08 42 3 v 1 2 8 A ug 2 00 0 s - and r - process elements in two very metal - poor stars

New measurements of neutron-capture elements are presented for two very metal-poor stars ([Fe/H] ∼ −3). One (LP 625-44) has an s-process signature believed to be due to mass transfer from a now-extinct metal-poor AGB companion, and the second (CS 22897-008) is one of a number of very metal-poor stars having high [Sr/Ba] ratios which is not expected from the r-process. In the sprocess star, many...