High-resolution study of the18Neexcited states relevant to the hot CNO cycle

The {sup 20}Ne(p,t)h{sup 18}Ne reaction has been studied in order to investigate the properties of {sup 18}Ne excited states. A missing 3{sup +} state of {sup 18}Ne, which could have a great influence on the {sup 17}F(p,{gamma})h{sup 18}Ne reaction rate, was searched for, but the existence of this state was not clearly verified. The spins and parities of the 5.11- and 5.15-MeV states were assigned tentatively by angular distribution measurements, as 2{sup +} and 3{sup {minus}}, respectively. We were able to resolve the doublets at 4.5, 5.1, and 6.3 MeV clearly for the first time due to our high precision system, which allowed us to determine the widths of some critical states above the proton threshold of {sup 18}Ne more precisely. {copyright} {ital 1999} {ital The American Physical Society}