## Triplet states in the Be atom: bound state spectrum and hyperfine structure    [PDF]

Alexei M. Frolov, Maria Belen Ruiz
The bound state spectrum of low-lying triplet states in the Be atom is investigated. In particular, we perform accurate computations of various bound triplet $S$, $P$, $D$, $F$, and $G$ states in the four-electron Be atom. For the $2^3S(L = 0)$ state in the Be atom we determine the hyperfine structure and a number of bound states properties by using results of highly accurate computations. The energies of the hyperfine structure levels for this state are $\varepsilon(F = \frac12)$ = -13725.927(7) $MHz$, $\varepsilon(F = \frac32)$ = -5490.371(7) $MHz$ and $\varepsilon(F = \frac52)$ = 8235.556(7) $MHz$, respectively. The observed hyperfine structure splittings for the the $2^3S(L = 0)$ state in the ${}^{9}$Be atom must be $\Delta_{12}$ = 8235.556(7) $MHz$ and $\Delta_{23}$ = 13725.927(7) $MHz$, respectively.
View original: http://arxiv.org/abs/1307.7424