Pulsed EPR study of low-dose irradiation effects in L-alanine crystals irradiated with γγ-rays, Ne and Si ion beams

Low-dose irradiation effects in l-alanine single crystals irradiated with γγ-rays, Ne and Si ion beams have been investigated by means of a two-pulse electron spin echo (ESE) technique. An effective phase memory time, TMTM, was measured from the first stable l-alanine radical, SAR1, and its complex relaxation mechanism is discussed. Both spectral and instantaneous diffusion contributions to the total effective relaxation rate have been extrapolated through the detection of the two-pulse ESE signal as a function of turning angle. The local microscopic concentration of paramagnetic centers C  (ions)/C(γC(γ-ray) for low-dose heavy-ion irradiation has been deduced from the corresponding spin–spin interaction.