806 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
Ratios of and Meson Decay Constants in Relativistic Quark Model
We calculate the ratios of and meson decay constants by applying the
variational method to the relativistic hamiltonian of the heavy meson. We adopt
the Gaussian and hydrogen-type trial wave functions, and use six different
potentials of the potential model. We obtain reliable results for the ratios,
which are similar for different trial wave functions and different potentials.
The obtained ratios show the deviation from the nonrelativistic scaling law,
and they are in a pretty good agreement with the results of the Lattice
calculations.Comment: 13 pages, 1 Postscript figur
Narratives of Industry Responses to Cyberbullying: Perspectives on Self-regulation From and About the Industry
In this chapter, we provide an overview of narratives about online inter- mediaries’ responses to cyberbullying from the perspectives of policy makers and the companies, as well as children and parents. Relevant self-regulatory and self- organisational efforts are discussed aswell as the rationales for their adoption; includ- ing how the effectiveness of these efforts is seen from the perspectives of various stakeholders. We draw attention to the relative paucity of data on effectiveness of companies’ mechanisms, particularly from the perspective of any benefits received by children as a result of these interventions and support
Effect of integrated care for sick listed patients with chronic low back pain: economic evaluation alongside a randomised controlled trial
Objective To evaluate the cost effectiveness, cost utility, and cost-benefit of an integrated care programme compared with usual care for sick listed patients with chronic low back pain
Identifying the quark content of the isoscalar scalar mesons f_0(980), f_0(1370), and f_0(1500) from weak and electromagnetic processes
The assignments of the isoscalar scalar mesons f0(980), f0(1370), and
f0(1500) in terms of their qqbar substructure is still a matter of heated
dispute. Here we employ the weak and electromagnetic decays D(s)(+) to f0+pi(+)
and f0 two-photon decays, respectively, to identify the f0(980) and f0(1500) as
mostly ssbar, and the f0(1370) as dominantly nonstrange, in agreement with
previous work. The two-photon decays can be satisfactorily described with quark
as well as with meson loops, though the latter ones provide a less
model-dependent and more quantitative description.Comment: v1, 15 pages, plain LaTeX, 1 eps figure. v2, 18 pages, plain LaTeX
(figure included). More discussion, especially on the f0(1370) and its
empirical two-photon widt
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
A Brief Etymology of the Collateral Circulation
It is well known that the protective capacity of the collateral circulation falls short in many individuals with ischemic disease of the heart, brain and lower extremities. In the past fifteen years, opportunities created by molecular and genetic tools, together with disappointing outcomes in many “angiogenic” trials, has led to a significant increase in the number of studies that focus on: 1) understanding the basic biology of the collateral circulation; 2) identifying the mechanisms that limit the collateral circulation’s capacity in many individuals; 3) devising methods to measure collateral extent, which has been found to vary widely among individuals; and 4) developing treatments to increase collateral blood flow in obstructive disease. Unfortunately, accompanying this increase in reports has been a proliferation of vague terms used to describe the disposition and behavior of this unique circulation, as well as the increasing miss-use of well-ensconced ones by new (and old) students of the collateral circulation. With this in mind, we provide a brief glossary of readily understandable terms to denote the formation, adaptive growth, and mal-adaptive rarefaction of the collateral circulation. We also propose terminology for several newly discovered processes that occur in the collateral circulation. Finally, we include terms used to describe vessels that are sometimes confused with collaterals, as well as terms describing processes active in the general arterial-venous circulation when ischemic conditions engage the collateral circulation. We hope this brief review will help unify the terminology used in collateral research
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
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