Although by 1938 some scientists, including Niels Bohr, were still reluctant to accept that Fermi had actually produced a new element, he was nevertheless awarded the Nobel Prize in Physics in November 1938 " " for his demonstrations of the existence of new radioactive elements produced by neutron irradiation, and for his related discovery of nuclear reactions brought about by slow neutrons " ".
42.
Its alpha radiation is rather weak ( 1.45 % with respect to ?-radiation ), but is sometimes used to detect this isotope . 247 Bk is an alpha-emitter with a long half-life of 1, 380 years, but it is hard to obtain in appreciable quantities; it is not formed upon neutron irradiation of plutonium because of the ?-stability of isotopes of curium isotopes with mass number below 248.
