SIMBAD references

We performed a statistical analysis of half-power pulse-widths of the core components in average pulsar profiles. We confirmed the existence of a lower bound of the distribution of half-power pulse-width versus the pulsar period W₅₀∼ 2°.45 P^–0.5 previously found by Rankin. Using our much larger data base we found W₅₀= (2°.51±0°.08) P^{–0.50±0.02} for 21 pulsars with double-pole interpulses for which measurement of the core component width was possible. On the other hand, all single-pole interpulse cases were found to lie in the swarm of pulsars above the boundary line. Using the Monte Carlo simulations based on exact geometrical calculations, we found that Rankin's method of estimation of the inclination angle α ≈ a sin(2°.45 P^–0.5/W₅₀) in pulsars with core components is quite good an approximation, except for very small angles α in the almost aligned rotators.