  Ab initio theory describes nuclei from a fully microscopic formulation, with
no presupposition of collective degrees of freedom, yet signatures of
clustering and rotation nonetheless arise. We can therefore look to ab initio
theory for an understanding of the nature of these emergent phenomena. To probe
the nature of rotation in 10Be, we examine the predicted rotational
spectroscopy from no-core configuration interaction (NCCI) calculations with
the Daejeon16 internucleon interaction, and find spectra suggestive of
coexisting rotational structures having qualitatively different intrinsic
deformations: one triaxial and the other with large axial deformation arising
primarily from the neutrons.
