RATES OF TRANSITIONS BETWEEN THE HYPERFINE-SPLITTING COMPONENTS OF THE GROUND-STATE AND THE 3.5 EV ISOMER IN TH-229(89+)

For the hydrogenlike Th-229(89+) ion, the rates of electromagnetic M1 transitions between hyperfine structure levels, originating from the n uclear 5/2(+) ground state and the first excited 3.5+/-1.0 eV 3/2(+) i someric state, are calculated. As a result of the mixing of the F = 2 components, these transitions turn out to be faster than the nuclear i someric gamma transition in a bare nucleus by several orders of magnit ude. The possibility of experimental observation of these transitions is discussed.