304 research outputs found
Search for charmonium and XYZ states in at BESIII
Within the framework of nonrelativistic quantum chromodynamics, we study the
production of charmonium states in at BESIII
with (n=1, 2, 3, and 4), (n=1, 2, and 3), and
(n=1 and 2). The radiative and relativistic corrections are
calculated to next-to-leading order for and wave states. We then argue
that the search for states such as , , ,
and in at BESIII may help clarify the nature
of these states. BESIII can search states through two body process
, where decay to , , or
. This result may be useful in identifying the nature of
states. For completeness, the production of charmonium in at B factories is also discussed.Comment: Comments and suggestions are welcome. References are update
Understanding the processes observed by Belle
We calculate the production cross sections for ,
and in annihilation through one virtual photon in the
framework of perturbative QCD with constituent quarks. The calculated cross
sections for and production are roughly in agreement
with the recent Belle data. The helicity decomposition for meson
production is also calculated. The fraction of the final
state in process is found to be 65%. The fraction of
production is 100% and is forbidden in annihilation
through one virtual photon. We further consider annihilation through
two virtual photons, and then find the fraction of in process to be about 91%.Comment: 8 pages, 2 figure
A hidden markov model for haplotype inference for present-absent data of clustered genes using identified haplotypes and haplotype patterns
The majority of killer cell immunoglobin-like receptor (KIR) genes are detected as either present or absent using locus-specific genotyping technology. Ambiguity arises from the presence of a specific KIR gene since the exact copy number (one or two) of that gene is unknown. Therefore, haplotype inference for these genes is becoming more challenging due to such large portion of missing information. Meantime, many haplotypes and partial haplotype patterns have been previously identified due to tight linkage disequilibrium (LD) among these clustered genes thus can be incorporated to facilitate haplotype inference. In this paper, we developed a hidden Markov model (HMM) based method that can incorporate identified haplotypes or partial haplotype patterns for haplotype inference from present-absent data of clustered genes (e.g., KIR genes). We compared its performance with an expectation maximization (EM) based method previously developed in terms of haplotype assignments and haplotype frequency estimation through extensive simulations for KIR genes. The simulation results showed that the new HMM based method outperformed the previous method when some incorrect haplotypes were included as identified haplotypes and/or the standard deviation of haplotype frequencies were small. We also compared the performance of our method with two methods that do not use previously identified haplotypes and haplotype patterns, including an EM based method, HPALORE, and a HMM based method, MaCH. Our simulation results showed that the incorporation of identified haplotypes and partial haplotype patterns can improve accuracy for haplotype inference. The new software package HaploHMM is available and can be downloaded at http://www.soph.uab.edu/ssg/files/People/KZhang/HaploHMM/haplohmm-index.html
Low expression of PTK6/Brk predicts poor prognosis in patients with laryngeal squamous cell carcinoma
Search for excited charmonium states in Annihilation at GeV
We suggest searching for excited charmonium states in annihilation
via double charmonium production at GeV with factories,
based on a more complete leading order calculation including both QCD and QED
contributions for various processes. In particular, for the C=+ states, the
(n=2,3) and (m=3,4) may have appreciable
potentials to be observed; while for the C=- states, the production
and especially the production might provide opportunities for
observing the with higher statistics in the future. A brief discussion
for the X(3940) observed in the double charmonium production is included.Comment: 13 pages and 8 figures in PRD version; QED contribution added;
experimental and theoretical developments since 2004 summarized; references
adde
Research Article
Pseudo almost automorphic and weighted pseudo almost automorphic mild solutions to a partial functional differential equation in Banach space
Problems of Double Charm Production in Annihilation at GeV
Using the nonrelativistic QCD(NRQCD) factorization formalism, we calculate
the color-singlet cross sections for exclusive production processes
~ and ~~
at the center-of-mass energy =10.6 GeV. The cross sections are
estimated to be 5.5fb, 6.7fb, 1.1fb, and 1.6fb for and , respectively. The calculated
production rate is smaller than the recent Belle data by about an order of
magnitude, which might indicate the failure of perturbative QCD calculation to
explain the double-charmonium production data. The complete
color-singlet cross section for is calculated. In addition, we also evaluate the ratio
of exclusive to inclusive production cross sections. The ratio of
production to production could be consistent
with the experimental data.Comment: 10 pages, 4 figures. A few references added, errors and typoes
correcte
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