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Based on the gravitational potential of an undisturbed finitely-thick disk derived by Peng et al. (1978), 3-D Monte Carlo simulations of 4 × 105 pulsars are made for the four combinations of the two parameters of gravitational potential (hz1 = 0.001 kpc , hz2 = 0.325 kpc ) and two parameters of initial velocity distribution (σv1 = 115 km/s , σv2 = 200 km/s ). The 4 × 105 pulsars are divided into 20 age-groups and the fraction of “escaped” pulsars is calculated for each group. The “not escaped” pulsars in each group, whose simulated projective positions on the Galactic plane lie in the two radial ranges 0 108yr), the Galactic disk thickness has an obvious and complex effect on the evolution of the pulsar's cumulative scale height, but for a relatively short time ( 0.325 kpc and σv2 = 200 km/s , the simulated cumulative scale height is 0.596 ± 0.005 kpc in the radial range 5

We present some interesting results from the mean pulse polarization observations of four southern pulsars made at the Australian National Radio Astronomy Observatory, Parkes, using the 64-m telescope in June and July, 1988. The 2 × 16 × 5 MHz filter system from Jodrell Bank has proved excellent in de-dispersing the pulse signals and measuring their polarization properties. We give the data for the four pulsars in some detail and discuss their spectral behaviour.

We have analysed a sample of 344 pulsars from three published catalogues. We adopt an empirical method for the correction of observational selection effects. The galactocentric distribution of pulsars displays a peak in the range 5 to 7 kpc. The total number of observable pulsars in the Galaxy is estimated to be (8.4 ± 3.7) × 104. Adopting a value of 5 for the beaming factor and an average lifetime of 9 million years, the birthrate of pulsars is found to be one in every 15 years to one in every 38 years. These results are consistent with some previous studies. The galactocentric distribution and birthrate are similar to those for supernova remnants.

We made a statistical analysis using the Cambridge 5km, 5 GHz data on double radio sources and found highly significant correlations between the following pairs of parameters; the energies in the hot spots and the extended regions, Eh and Ee; their luminosities, Lh and Le; energy density in the hot spots K and the total luminosity Lt and the ratio of energy densities K A and Lt. These correlations exemplify the role of the hot spots in the radio sources.

The estimation of some important parameters of pulsars is discussed. The results have been compared with the RS model and applied to the estimation of radio luminosity and the beaming factor.