21,433 research outputs found
Bosonic Super Liouville System: Lax Pair and Solution
We study the bosonic super Liouville system which is a statistical
transmutation of super Liouville system. Lax pair for the bosonic super
Liouville system is constructed using prolongation method, ensuring the Lax
integrability, and the solution to the equations of motion is also considered
via Leznov-Saveliev analysis.Comment: LaTeX, no figures, 11 page
Radiative decays of charmonium into light mesons
We apply perturbative QCD to the radiative decays of charmonia and into light mesons. We perform a complete numerical calculation for the quark-gluon loop diagrams involved in these processes. The calculated decay branching ratios to P-wave mesons and fit the data well, while that of (if treated as an meson) is predicted to be , which implies that can not be the or meson. Decays of P-wave charmonia (J=0,1,2) are also studied, and the branching ratio of is predicted to be , which may be tested by CLEO-c and BESIII with future experiments
Next-to-Leading Order QCD Correction to at GeV}
One of the most challenging open problems in heavy quarkonium physics is the
double charm production in annihilation at B factories. The measured
cross section of is much larger than leading
order (LO) theoretical predictions. With the nonrelativistic QCD factorization
formalism, we calculate the next-to-leading order (NLO) QCD correction to this
process. Taking all one-loop self-energy, triangle, box, and pentagon diagrams
into account, and factoring the Coulomb-singular term into the bound
state wave function, we get an ultraviolet and infrared finite correction to
the cross section of at GeV. We
find that the NLO QCD correction can substantially enhance the cross section
with a K factor (the ratio of NLO to LO) of about 1.8-2.1; hence it greatly
reduces the large discrepancy between theory and experiment. With and , the NLO cross section is estimated to be 18.9 fb, which
reaches to the lower bound of experiment.Comment: Version appeared in PRL, Figure 3 added showing the renormalization
scale dependence of the cross section, new BaBar data adde
The first operation and results of the Chung-Li VHF radar
The Chung-Li Very High Frequency (VHF) radar is used in the dual-mode operations, applying Doppler beam-swinging as well as the spaced-antenna-drift method. The design of the VHF radar is examined. Results of performance tests are discussed
Amine-terminated nanoparticle films: pattern deposition by a simple nanostencilling technique and stability studies under X-ray irradiation
Exploring the surface chemistry of nanopatterned amine-terminated nanoparticle films.</p
On the theoretical and experimental uncertainties in the extraction of the J/psi absorption cross section in cold nuclear matter
We investigate the cold nuclear matter effects on production, whose
understanding is fundamental to study the quark-gluon plasma. Two of these
effects are of particular relevance: the shadowing of the parton distributions
and the nuclear absorption of the pair. If 's are not
produced {\it via} a process as suggested by recent theoretical
works, one has to modify accordingly the way to compute the nuclear shadowing.
This naturally induces differences in the absorption cross-section fit to the
data. A careful analysis of these differences however requires taking into
account the experimental uncertainties and their correlations, as done in this
work for Au collisions at \sqrtsNN=200\mathrm{GeV}, using several
shadowing parametrisations.Comment: 6 pages, 1 table, 3 figures, Submitted to J. Phys. G, talk given at
the International Conference on Strangeness in Quark Matter (SQM2009),
Buzios, Brasil, Sep. 27 - Oct. 2, 200
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