Distribution of 115 Galactic binary radio pulsars in the PṖ–diagram. The error bars are much smaller than the size of each symbol. The caption to the right explains the nature of the companion stars. Pulsars with a He WD companion marked by a circle are discussed in Sect. 7.5.1. The B-fields (dashed lines) and the spin-up lines (grey lines) were calculated following Tauris et al. (2012) and assuming M_NS = 1.4 M_⊙ and sinα = φ = ω_c = 1. Data taken from the ATNF Pulsar Catalogue in March 2013. All observed Ṗ values were corrected for kinematic effects. The grey-shaded areas mark empty regions that cannot be populated according to current recycling scenarios.