ar X iv : a st ro - p h / 03 11 44 5 v 1 1 9 N ov 2 00 3 Multiscale self - organized criticality and powerful X - ray flares

ar X iv : a st ro - p h / 01 11 13 6 v 1 7 N ov 2 00 1 1 Active Optics in Modern , Large Optical Telescopes

ar X iv : a st ro - p h / 06 11 09 9 v 1 2 N ov 2 00 6 Nuclear Activity in UZC Compact Groups of Galaxies

ar X iv : a st ro - p h / 03 11 60 3 v 1 2 7 N ov 2 00 3 A search for emission line galaxies at z = 6 . 5

We are carrying out a search for Lyα emitting galaxies at z = 6.5 employing slitless spectroscopy at the VLT. In our 43 arcmin field we find three isolated single emission lines with SEDs consistent with line emitting galaxies at z = 6.5.

ar X iv : a st ro - p h / 01 03 44 4 v 1 2 7 M ar 2 00 1 From Centimeter to Millimeter Wavelengths : A High Angular Resolution Study of 3 C 273

We monitored 3C 273 with VLBI at 15–86 GHz since 1990. We discuss component trajectories, opacity effects, a rotating jet, and outburst-ejection relations from Gamma-ray to radio bands.

ar X iv : a st ro - p h / 05 11 15 9 v 1 6 N ov 2 00 5 1 EMISSION MEASURE DISTRIBUTION AND ABUNDANCES MEASUREMENTS DURING HIGH - T FLARES

The RSCVn system σ Geminorum was observed by XMM-Newton on April 2001 during a large flare. We model the emission measure distribution (EMD) during the flare and during a quiescence period. In the flare, a two phase behaviour is found in which the cool plasma (kT < 2 keV) is not disturbed while a large hot component , at temperatues of kT > 3 keV emerges. Fundamental limitations on EMD modeling...