  An attractive Bose-Einstein condensate in two spatial dimensions is expected
to collapse for supercritical values of the interaction strength. Moreover, it
is known that for nonzero quanta of angular momentum and infinitesimal
attraction the gas prefers to fragment and distribute its angular momentum over
different orbitals. In this work we examine the two-dimensional Bose gas for
finite values of attraction and describe the ground state in connection to its
angular momentum by theoretical methods that go beyond the standard
Gross-Pitaevskii theory. By applying the best mean field approach, we derive
analytical relations for the energy, the fragmentation of the ground states and
the critical (for collapse) value of the attraction strength as a function of
the total angular momentum $L$.
