Observation of cold, long-lived antiprotonic helium ions.
نویسندگان
چکیده
Cold, two-body antiprotonic helium ions p 4He2+ and p 3He2+ with 100-ns-scale lifetimes, occupying circular states with the quantum numbers ni=28-32 and li=ni-1 have been observed. They were produced by cooling three-body antiprotonic helium atoms in an ultra-low-density helium target at temperature T approximately 10 K by atomic collisions, and then removing their electrons by inducing a laser transition to an autoionizing state. The lifetimes of p 3He2+ against annihilation induced by collisions were shorter than those of p 4He2+, and decreased for larger-ni states.
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ورودعنوان ژورنال:
- Physical review letters
دوره 94 6 شماره
صفحات -
تاریخ انتشار 2005