LOW-TEMPERATURE MAGNETORESONANCE LINE BRO ADENING IN SUBSTANCES OF POLARIZED NUCLEAR TARGETS

The temperature dependence of electron spin resonance linewidth in the substance of polarized nuclear target based on the stable chromium co mplex diluted in propanediol (HMBA (Cr(V))Na) is studied. Experiments were carried out at frequencies about 75 GHz in temperature range 0,3- 4,2 K. It is shown that temperature line broadening of such structure- disordered magnetic is good described by the model of magnetic two-lev el systems. It allows to assume that in such substances of polarized n uclear targets the frozed disordered system of spins, like spin-glass system in magnetics, with a strong exchange interactions is formed.