ar X iv : a st ro - p h / 06 10 69 9 v 1 2 4 O ct 2 00 6 High resolution spectroscopy of halo stars within the spectral region 3550 – 5000 ÅÅ

ar X iv : a st ro - p h / 06 10 24 6 v 1 9 O ct 2 00 6 Special Features of Galactic Dynamics

ar X iv : a st ro - p h / 06 10 46 7 v 1 1 6 O ct 2 00 6 Spectroscopic Analysis of subluminous B Stars in Binaries

The masses of compact objects like white dwarfs, neutron stars and black holes are fundamental to astrophysics, but very difficult to measure. We present the results of an analysis of subluminous B (sdB) stars in close binary systems with unseen compact companions to derive their masses and clarify their nature. Radial velocity curves were obtained from time resolved spectroscopy. The atmospher...

ar X iv : a st ro - p h / 06 11 03 3 v 1 1 N ov 2 00 6 On the Progenitor of Supernova 1987 A

A previously unpublished ultralow–dispersion spectrum of Sanduleak -69 202, the stellar progenitor of SN 1987A, is presented and the uncertain presupernova evolution of Sanduleak -69 202 is discussed. Subject headings: Supernovae: individual (SN 1987A) — techniques: ultralow– dispersion spectra — Large Magellanic Cloud — supergiants — stars: Sanduleak -69 202

ar X iv : a st ro - p h / 03 10 56 2 v 1 2 0 O ct 2 00 3 First results from a Chandra survey of the ’ Bar ’ region of the SMC

We present the first results from a Chandra survey of the central region of the Small Magellanic Cloud. We detect a total of 122 sources down to a limiting luminosity of ∼ 4.3 × 10erg s(corrected for Galactic NH), which is ∼ 10 times lower than in any previous survey of the SMC. We identify 20 candidate transient sources: eighteen previously known sources in this area which are not detected in ...

ar X iv : a st ro - p h / 06 10 59 3 v 1 1 9 O ct 2 00 6 The Zoo of Neutron Stars

In these lecture notes I briefly discuss the present day situation and new discoveries in astrophysics of neutron stars focusing on isolated objects. The latter include soft gamma repeaters, anomalous X-ray pulsars, central compact objects in supernova remnants, the Magnificent seven, and rotating radio transients. In the last part of the paper I describe available tests of cooling curves of ne...