U [kV]		E* [GV/m]	v [km/s]	error of v [km/s]
16		1.28		25,7		2,3
18		1.44		27		2,4
20		1.60		29,2		2,8
22		1.76		33,5		3,2

*calculated from U by E = U / (5*r) with r=5e-6 m