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Flavor Asymmetry of the Nucleon Sea and the Five-Quark Components of the Nucleons  [PDF]
Wen-Chen Chang,Jen-Chieh Peng
Physics , 2011, DOI: 10.1103/PhysRevLett.106.252002
Abstract: The existence of the five-quark Fock states for the intrinsic charm quark in the nucleons was suggested some time ago, but conclusive evidence is still lacking. We generalize the previous theoretical approach to the light-quark sector and study possible experimental signatures for such five-quark states. In particular, we compare the $\bar d - \bar u$ and $\bar u + \bar d - s -\bar s$ data with the calculations based on the five-quark Fock states. The qualitative agreement between the data and the calculations is interpreted as evidence for the existence of the intrinsic light-quark sea in the nucleons. The probabilities for the $|uudu\bar{u}>$ and $|uudd\bar{d}>$ Fock states are also extracted.
Five-quark components in baryons  [PDF]
B. S. Zou
Physics , 2010, DOI: 10.1016/j.nuclphysa.2010.01.194
Abstract: Evidence has been accumulating for the existence of significant intrinsic non-perturbative five-quark components in various baryons. The inclusion of the five-quark components gives a natural explanation of the excess of $\bar d$ over $\bar u$, significant quark orbital angular momentum in the proton, the problematic mass and decay pattern of the lowest $1/2^-$ baryon nonet, etc.. A breathing mode of $qqq\leftrightarrow qqqq\bar q$ is suggested for the lowest $1/2^-$ baryon octet. Evidence of a predicted member of the new scheme, $\Sigma^*(1/2^-)$ around 1380 MeV, is introduced.
Five-quark components in $Δ(1232)\to Nπ$ decay  [PDF]
Q. B. Li,D. O. Riska
Physics , 2005, DOI: 10.1103/PhysRevC.73.035201
Abstract: Five-quark $qqqq\bar q$ components in the $\Delta(1232)$ are shown to contribute significantly to $\Delta(1232)\to N\pi$ decay through quark-antiquark annihilation transitions. These involve the overlap between the $qqq$ and $qqqq\bar q$ components and may be triggered by the confining interaction between the quarks. With a $\sim$ 10% admixture of five-quark components in the $\Delta(1232)$ the decay width can be larger by factors 2 - 3 over that calculated in the quark model with 3 valence quarks, depending on the details of the confining interaction. The effect of transitions between the $qqqq\bar q$ components themselves on the calculated decay width is however small. The large contribution of the quark-antiquark annihilation transitions thus may compensate the underprediction of the width of the $\Delta(1232)$ by the valence quark model, once the $\Delta(1232)$ contains $qqqq\bar q$ components with $\sim$ 10% probability.
Single spin asymmetry and five-quark components of the proton
Wei, F. X.;Zou, B. S.
High Energy Physics - Phenomenology , 2008,
Abstract: We examine the single-spin asymmetry (SSA) caused by the five-quark components of the proton for semi-inclusive electroproduction of charged pions in deep-inelastic scattering on a transversely polarized hydrogen target. The large SSA is considered to have close relation with quark orbital motion in the proton and suggests that the quark orbital angular momentum is nonzero. For the five-quark $qqqq\bar{q}$ components of the proton, the lowest configurations with $qqqq$ system orbitally excited and the $\bar{q}$ in the ground state would give spin-orbit correlations naturally for the quarks in a polarized proton. We show that based on the basic reaction $\gamma q \to \pi q'$, the orbital-spin coupling of the probed quarks in the five-quark configuration leads to the single-spin asymmetry consistent with recent experiment results.
Nucleon sea and the five-quark components  [PDF]
Jen-Chieh Peng,Wen-Chen Chang
Physics , 2012,
Abstract: We generalize the approach of Brodsky {\it et al.} for the intrinsic charm quark distribution in the nucleons to the light-quark sector involving intrinsic $\bar u, \bar d, s$ and $\bar s$ sea quarks. We compare the calculations with the existing $\bar d - \bar u$, $s + \bar s$, and $\bar u + \bar d - s -\bar s$ data. The good agreement between the theory and the data is interpreted as evidence for the existence of the intrinsic light-quark sea in the nucleons. The probabilities for the $|uudu\bar{u}>$, $|uudd\bar{d}>$ and $|uuds\bar{s}>$ Fock states are also extracted.
Role of five-quark components in radiative and strong decays of the Lambda(1405) resonance  [PDF]
C. S. An,B. Saghai,S. G. Yuan,Jun He
Physics , 2010, DOI: 10.1103/PhysRevC.81.045203
Abstract: Within an extended chiral constituent quark model, three- and five-quark structure of the $S_{01}$ resonance $\Lambda(1405)$ is investigated. Helicity amplitudes for the electromagnetic decays ($\Lambda(1405) \to \Lambda(1116)\gamma$, $\Sigma(1194)\gamma$), and transition amplitudes for strong decays ($\Lambda(1405)\to\Sigma(1194)\pi$, $ K^{-}p$) are drived, as well as the relevant decay widths. The experimental value for the strong decay width, $\Gamma_{\Lambda(1405)\to (\Sigma \pi)^\circ}=50\pm 2$ MeV, is well reproduced with about 50% of five-quark admixture in the $\Lambda(1405)$. Important effects due to the configuration mixings among $\Lambda^{2}_{1}P_{A}$, $\Lambda^{2}_{8}P_{M}$ and $\Lambda^{4}_{8}P_{M}$ are found. In addition, transitions between the three- and five-quark components in the baryons turn out to be significant in both radiative and strong decays of the $\Lambda(1405)$ resonance.
The Neutrosophic Entropy and its Five Components  [PDF]
Vasile Patrascu
Computer Science , 2015,
Abstract: This paper presents two variants of penta-valued representation for neutrosophic entropy. The first is an extension of Kaufmann's formula and the second is an extension of Kosko's formula. Based on the primary three-valued information represented by the degree of truth, degree of falsity and degree of neutrality there are built some penta-valued representations that better highlights some specific features of neutrosophic entropy. Thus, we highlight five features of neutrosophic uncertainty such as ambiguity, ignorance, contradiction, neutrality and saturation. These five features are supplemented until a seven partition of unity by adding two features of neutrosophic certainty such as truth and falsity. The paper also presents the particular forms of neutrosophic entropy obtained in the case of bifuzzy representations, intuitionistic fuzzy representations, paraconsistent fuzzy representations and finally the case of fuzzy representations.
Revisiting Scalar and Pseudoscalar Couplings with Nucleons  [PDF]
Hai-Yang Cheng,Cheng-Wei Chiang
Physics , 2012, DOI: 10.1007/JHEP07(2012)009
Abstract: Certain dark matter interactions with nuclei are mediated possibly by a scalar or pseudoscalar Higgs boson. The estimation of the corresponding cross sections requires a correct evaluation of the couplings between the scalar or pseudoscalar Higgs boson and the nucleons. Progress has been made in two aspects relevant to this study in the past few years. First, recent lattice calculations show that the strange-quark sigma term $\sigma_s$ and the strange-quark content in the nucleon are much smaller than what are expected previously. Second, lattice and model analyses imply sizable SU(3) breaking effects in the determination on the axial-vector coupling constant $g_A^8$ that in turn affect the extraction of the isosinglet coupling $g_A^0$ and the strange quark spin component $\Delta s$ from polarized deep inelastic scattering experiments. Based on these new developments, we re-evaluate the relevant nucleon matrix elements and compute the scalar and pseudoscalar couplings of the proton and neutron. We also find that the strange quark contribution in both types of couplings is smaller than previously thought.
Performance Analysis of HR Portal Domain Components Extraction  [PDF]
N. Md. Jubair Basha,Salman Abdul Moiz,A. A. Moiz Qyser
Computer Science , 2012,
Abstract: Extraction of components pertaining to a particular domain not only reduces the cost but also helps in delivering a quality product. However, the advantages of the Component Level Interaction's (CLI's) are not clearly presented. In the first part of the paper the design of HR Portal application is described. Later the results are simulated using the Netbeans Profiler tool which exposes and highlights the performance characteristics of component based system pertaining to HR domain.
Extraction of Unique Independent Components for Nonlinear Mixture of Sources  [cached]
Pei Gao,Li Chin Khor,Wai Lok Woo,Satnam Singh Dlay
Journal of Computers , 2007, DOI: 10.4304/jcp.2.6.9-16
Abstract: In this paper, a neural network solution to extract independent components from nonlinearly mixed signals is proposed. Firstly, a structurally constrained mixing model is introduced to extend the recently proposed mono-nonlinearity mixing model, allowing that different nonlinear distortion are applied to each source signal. Based on this nonlinear mixing model, a novel demixing system characterized by polynomial neural network is then proposed for recovering the original sources. The parameter learning algorithm is derived mathematically based on the minimum mutual information principle. It is shown that unique extraction of independent components can be achieved by optimizing the mutual information cost function under both model structure and signal constraints. In this framework, the theory of series reversion is developed with the aim to perform dual optimization on the polynomials of the proposed demixing system. Finally, simulation results are presented to verify the efficacy of the proposed approach.
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