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Figure 1: Four shots from the time evolution of a gaussian wavepacket monitored by a gaussian detector placed at the center of the plane. The efficiency of the detector is in this case ca.

  
Figure 2: Probability density of time of arrival for a Dirac's delta counter placed at x=0, coupling constant alpha. The incoming wave packet starts at t=0, x=-4, with velocity v=4

  
Figure 3: Rescaled probability densities of Fig.1

  
Figure 4: Optimal coupling constant as a function of velocity of the incoming wave packet. The dependence pretty soon saturates to a linear one. At the saturation value

  
Figure 5: as a function of for a static wave packet centered over the counter. The maximum, of is reached for

  
Figure 6: as a function of velocity v and coupling constant for a static wave packet centered over the detector.