19 research outputs found
The Hyperfine Spin Splittings In Heavy Quarkonia
The hyperfine spin splittings in heavy quarkonia are studied using the
recently developed renormalization group improved spin-spin potential which is
independent of the scale parameter . The calculated energy difference
between the and the fits the experimental data well, while
the predicted energy difference between the center of the gravity
of states and the state of charmonium has the correct
sign but is somewhat larger than the experimental data. This is not surprising
since there are several other contributions to , which we discuss,
that are of comparable size ( MeV) that should be included, before
precise agreement with the data can be expected. The mass differences of the
, , , and
are also predicted.Comment: 17 page