Phenomenological study of J/ψ→Ξ0(Λπ0)Ξˉ0(Λˉγ)J/\psi\to\Xi^0(\Lambda \pi^0) \bar{\Xi}^0(\bar{\Lambda} \gamma) decays

The measurement of decay parameters is one of the important goals of particle physics experiments, and the measurement serves as a probe to search for evidence of CP violation in baryonic decays. The experimental results will help advance existing theoretical research and establish new experimental objectives. In this paper, we formulate the asymmetric parameters that characterize parity violation, and then derive formulas for the measurement of CP violation. The formulae for the joint angular distribution of the full decay chain as well as the polarization observable of $\Xi ^ 0$, $\bar { \Xi } ^ 0$, $\Lambda$ and $\bar { \Lambda }$ are also provided for experiments. Lastly, we evaluated the sensitivity of two asymmetric parameters: $\alpha _ { \Xi ^ 0 \to \Lambda \pi ^ 0 }$ (abbreviated as $\alpha _ { \Xi ^ 0 }$) and $\alpha _ { \bar { \Xi } ^ 0 \to \bar { \Lambda } \gamma }$ (abbreviated as $\alpha_ {\bar{\Xi}^0 }$) for future experimental measurement.Comment: 8 pages, 5 figure

Identification and association of the single nucleotide polymorphisms in calpain3 (CAPN3) gene with carcass traits in chickens

<p>Abstract</p> <p>Background</p> <p>The aim of this study is to screen single nucleotide polymorphisms (SNP) of chicken <it>Calpain3 </it>(<it>CAPN3</it>) gene and to analyze the potential association between <it>CAPN3 </it>gene polymorphisms and carcass traits in chickens. We screened <it>CAPN3 </it>single nucleotide polymorphisms (SNP) in 307 meat-type quality chicken from 5 commercial pure lines (S01, S02, S03, S05, and D99) and 4 native breeds from Guangdong Province (Huiyang Huxu chicken and Qingyuan Ma chicken) and Sichuan Province (Caoke chicken and Shandi Black-bone chicken), China.</p> <p>Results</p> <p>Two SNPs (11818T>A and 12814T>G) were detected by single strand conformation polymorphism (SSCP) method and were verified by DNA sequencing. Association analysis showed that the 12814T>G genotypes were significantly associated with body weight (BW), carcass weight (CW), breast muscle weight (BMW), and leg muscle weight (LMW). Haplotypes constructed on the two SNPs (H1, TG; H2, TT; H3, AG; and H4, AT) were associated with BW, CW (<it>P </it>< 0.05), eviscerated percentage (EP), semi-eviscerated percentage (SEP), breast muscle percentage (BMP), and leg muscle percentage (LMP) (<it>P </it>< 0.01). Diplotype H1H2 was dominant for BW, CW, and LMP, and H2H2 was dominant for EP, SEP, and BMP.</p> <p>Conclusion</p> <p>We speculated that the <it>CAPN3 </it>gene was a major gene affecting chicken muscle growth and carcass traits or it was linked with the major gene(s). Diplotypes H1H2 and H2H2 might be advantageous for carcass traits.</p

Productions of X(1835) as baryonium with sizable gluon content

The X(1835) has been treated as a baryonium with sizable gluon content, and to be almost flavor singlet. This picture allows us to rationally understand X(1835) production in $J/\psi$ radiative decays, and its large couplings with $p\bar{p}$, $\eta^{\prime}\pi\pi$. The processes $\Upsilon(1S)\to \gamma X(1835)$ and $J/\psi\to \omega X(1835)$ have been examined. It has been found that $Br(\Upsilon(1S)\to\gamma X(1835))Br(X(1835)\to p\bar{p})<6.45\times10^{-7}$, which is compatible with CLEO's recently experimental result (Phys.Rev.$\mathbf{D73}$ (2006) 032001;hep-ex/0510015). The branching fractions of $Br(J/\psi\to\omega X(1835))$, $Br(J/\psi\to\rho X(1835))$ with $X(1835)\to p\bar{p}$ and $X(1835)\to\eta^{\prime}\pi^{+}\pi^{-}$ have been estimated by the quark-pair creation model. We show that they are heavily suppressed, so the signal of X(1835) is very difficult, if not impossible, to be observed in these processes. The experimental checks for these estimations are expected. The existence of the baryonium nonet is conjectured, and a model independent derivation of their production branching fractions is presented.Comment: 21 pages, 4 figure