ar X iv : a st ro - p h / 97 11 16 3 v 1 1 4 N ov 1 99 7 Infrared observations of cataclysmic variables

ar X iv : a st ro - p h / 97 11 24 4 v 1 2 0 N ov 1 99 7 POPULATION SYNTHESIS OF HIGH ENERGY TRANSIENTS RELATIVISTIC BINARY MERGING RATES

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 / 97 11 18 2 v 1 1 7 N ov 1 99 7 Warps and Secondary

Secondary infall in galaxies could cause the angular momentum of the outer halo to change its orientation. The generation of warps due to this effect is studied using N-body simulations.

ar X iv : a st ro - p h / 96 11 14 3 v 1 1 9 N ov 1 99 6 A high deuterium abundance in the early Universe

ar X iv : a st ro - p h / 05 11 46 1 v 1 15 N ov 2 00 5 Spectroscopy of Four Cataclysmic Variables with Periods above 7 Hours 1

We present spectroscopy of four cataclysmic variables. Using radial velocity measurements, we find orbital periods Porb for the first time. The stars and their periods are GY Hya, 0.347230(9) d; SDSS J204448-045929, 1.68(1) d; V392 Hya, 0.324952(5) d; and RX J1951.7+3716, 0.492(1) d. We also detect the spectra of the secondary stars, estimate their spectral types, and derive distances based on ...