Figure 10

Figure 10: Dependence of the dimensionless strain amplitude for a WD + WD detached system with initial masses of the components of 0.6M ⊙ + 0.6 M ⊙ (red line), a WD + WD system with 0.6M ⊙ + 0.2M ⊙ (blue line) and a WD + NS system with 1.4M ⊙ + 0.2 M ⊙ (green line). All systems have an initial separation of components 1 R ⊙ and are assumed to be at a distance of 1 kpc (i.e. the actual strength of the signal has to be scaled with factor 1 ∕d, with d in kpc). For the DD system the line shows an evolution into contact, while for the two other systems the upper branches show pre-contact evolution and lower branches – a post-contact evolution with mass exchange. The total time-span of evolution covered by the tracks is 13.5 Gyr. Red dots mark the positions of systems with mass-ratio of components q = 0.02 below which the conventional picture of evolution with a mass exchange may be not valid. The red dashed line marks the position of the confusion limit as determined in [287].