Untersuchung von 0+−0+-Übergängen in12C,24Mg,28Si,32S und40Ca durch unelastische Elektronenstreuung

Transitions from the 0⁺ ground states to 0⁺ excited states at 7.65 (¹²C), 6.44 (²⁴Mg), 4.98 and 6.69 (²⁸Si), 3.78 (³²S) and 3.35 (⁴⁰Ca) MeV have been studied with 28 to 60 MeV electrons at scattering angles from 105 to 165°. Matrix elements and transition radii have been deduced, using DWBA-calculations. The monopole excitations can be uniquely distinguished from electric quadrupole excitations by the angular dependence of the cross sections. Some results forE2- andE3-transitions in¹²C,²⁸Si,³²S and⁴⁰Ca are given, too.