690 research outputs found
Canonical Charmonium Interpretation for Y(4360) and Y(4660)
In this work, we consider the canonical charmonium assignments for Y(4360)
and Y(4660). Y(4660) is good candidate of state, the
possibility of Y(4360) as a state is studied, and the
charmonium hybrid interpretation of Y(4360) can not be excluded completely. We
evaluate the leptonic widths, E1 transitions, M1 transitions and
the open flavor strong decays of Y(4360) and Y(4660). Experimental tests for
the charmonium assignments are suggested.Comment: 32 pages, 4 figure
Strange-Beauty Meson Production at Colliders
The production rates and transverse momentum distributions of the
strange-beauty mesons and at colliders are calculated
assuming fragmentation is the dominant process. Results are given for the
Tevatron in the large transverse momentum region, where fragmentation is
expected to be most important.Comment: Minor changes in the discussion section. Also available at
http://www.ph.utexas.edu/~cheung/paper.htm
On the and as Bound States and Approximate Nambu-Goldstone Bosons
We reconsider the two different facets of and mesons as
bound states and approximate Nambu-Goldstone bosons. We address several topics,
including masses, mass splittings between and and between and
, meson wavefunctions, charge radii, and the wavefunction overlap.Comment: 15 pages, late
Adapting group schema therapy for older adults with personality disorders:Lessons learnt
A first empirical study into group schema therapy in older adults with mood disorders and personality disorder (PD) features has shown that brief group schema therapy has potential to decrease psychological distress and to change early maladaptive schemas (EMS). Effect sizes however were smaller than those found in similar studies in younger adults. Therefore, we set out to adapt the treatment protocol for older adults in order to enhance its feasibility and outcome in this age group. We examined this adapted protocol in 29 older adults (mean age 66 years) with PDs from four Dutch mental health institutes. The primary outcome was symptomatic distress, measured by the Brief Symptom Inventory. Secondary outcomes were measured by the Young Schema Questionnaire, the Schema Mode Inventory, and the short version of the Severity Indices of Personality Problems. Contrary to our expectations, the adapted treatment protocol yielded only a small effect size in our primary outcome, and no significant improvement in EMS, modes and personality functioning. Patients pointed out that they were more aware of their dysfunctional patterns, but maybe they had not been able yet to work on behavioural change due to this schema therapy treatment being too brief. We recommend more intensive treatment for older patients with PDs, as they might benefit from more schema therapy sessions, similar to the treatment dosage in younger PD patients. They might also benefit from a combination of group therapy and individual treatment sessions
Decay Constants and Semileptonic Decays of Heavy Mesons in Relativistic Quark Model
We investigate the and mesons in the relativistic quark model by
applying the variational method with the Gaussian wave function. We calculate
the Fermi momentum parameter , and obtain
GeV, which is almost independent of the input parameters, , ,
and . We then calculate the ratio /, and obtain the
result which is larger, by the factor of about 1.3, than
given by the naive nonrelativistic analogy. This result is in a good agreement
with the recent Lattice calculations. We also calculate the ratio
/. In these calculations the wave function at
origin is essential. We also determine by comparing the
theoretical prediction of the ACCMM model with the lepton energy spectrum of from the recent ARGUS analysis, and find that
GeV, when we use GeV. However, this
experimentally determined value of is strongly dependent on the value
of input parameter .Comment: 15 pages (Latex) (uses epsfig.sty, 1 figure appended as a uuencoded
compressed ps-file
Leptonic widths of high excitations in heavy quarkonia
Agreement with the measured electronic widths of the ,
, and resonances is shown to be reached if two
effects are taken into account: a flattening of the confining potential at
large distances and a total screening of the gluon-exchange interaction at
r\ga 1.2 fm. The leptonic widths of the unobserved and
resonances: keV and
keV are predicted.Comment: 11 pages revtex
The decay constants of pseudoscalar mesons in a relativistic quark model
The decay constants of pseudoscalar mesons are calculated in a relativistic
quark model which assumes that mesons are made of a valence quark antiquark
pair and of an effective vacuum like component. The results are given in terms
of quark masses and of some free parameters entering the expression of the
internal wave functions of the mesons. By using the pion and kaon decay
constants to fix the parameters of the
model one gets for the light quark masses
and the heavy quark masses in the
range: . In the case of
light neutral mesons one obtains with the same set of parameters
. The
values are in agreement with the experimental data and other theoretical
results.Comment: 11 pages, LaTe
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