We discuss four recycled pulsars found in Arecibo drift-scan searches. PSR J1944+0907 has a spin period of 5.2ms and is isolated. The 5.8-ms pulsar J1453+19 may have a low-mass companion. The isolated 56-ms pulsar J0609+2130 is possibly the remnant of a disrupted double neutron star binary. The 41-ms pulsar J1829+2456 is in a relativistic orbit; its companion is most likely another neutron star.

Preliminary positions and magnitudes derived from the analysis of 12 weeks of observations from the Hipparcos star mappers are systematically compared with the various sources of ground-based data used in the Hipparcos Input Catalogue. These comparisons allow to cross-check the accuracies claimed by the various sources of ground-based data and by the analysis method of star mapper data. The par...

The observed samples of supernovae (SN) and double compact objects (DCOs) provide several critical constraints on population-synthesis models: the parameters of these models must be carefully chosen to reproduce, among other factors, (i) the formation rates of double neutron star (NS-NS) binaries and of white dwarf-neutron star (WD-NS) binaries and (ii) the type II and Ib/c supernova rates. Eve...