, p.44320 , 2017-04-24 , American Physical Society (APS)
We show that correlated Gaussians with good angular momentum and parity provide flexible basis functions for specific elongated shape. As an application we study linear-chain states of four a particles in variation-after-projection calculations in which all the matrix elements are evaluated analytically. We find possible chain states for J(pi) = 0(+), 2(+), 4(+) and perhaps 6(+) with the bandhead energy being about 33 MeV from the ground state of O-16. No chain states with J >= 8 are found. The nature of the rotational sequence of the chain states is clarified in contrast to a rigid-body rotation. The quadrupole deformation parameters estimated from the chain states increase from 0.59 to 1.07 for 2(+) to 6(+). This work suggests undeveloped fields for the correlated Gaussians beyond those problems which have hitherto been solved successfully.