Observation of a ppb mass threshoud enhancement in \psi^\prime\to\pi^+\pi^-J/\psi(J/\psi\to\gamma p\bar{p}) decay

The decay channel $\psi^\prime\to\pi^+\pi^-J/\psi(J/\psi\to\gamma p\bar{p})$ is studied using a sample of $1.06\times 10^8$ $\psi^\prime$ events collected by the BESIII experiment at BEPCII. A strong enhancement at threshold is observed in the $p\bar{p}$ invariant mass spectrum. The enhancement can be fit with an $S$-wave Breit-Wigner resonance function with a resulting peak mass of $M=1861^{+6}_{-13} {\rm (stat)}^{+7}_{-26} {\rm (syst)} {\rm MeV/}c^2$ and a narrow width that is $\Gamma<38 {\rm MeV/}c^2$ at the 90% confidence level. These results are consistent with published BESII results. These mass and width values do not match with those of any known meson resonance.Comment: 5 pages, 3 figures, submitted to Chinese Physics

Genome-Wide Association Study Identifies ALDH7A1 as a Novel Susceptibility Gene for Osteoporosis

Osteoporosis is a major public health problem. It is mainly characterized by low bone mineral density (BMD) and/or low-trauma osteoporotic fractures (OF), both of which have strong genetic determination. The specific genes influencing these phenotypic traits, however, are largely unknown. Using the Affymetrix 500K array set, we performed a case-control genome-wide association study (GWAS) in 700 elderly Chinese Han subjects (350 with hip OF and 350 healthy matched controls). A follow-up replication study was conducted to validate our major GWAS findings in an independent Chinese sample containing 390 cases with hip OF and 516 controls. We found that a SNP, rs13182402 within the ALDH7A1 gene on chromosome 5q31, was strongly associated with OF with evidence combined GWAS and replication studies (P = 2.08×10−9, odds ratio = 2.25). In order to explore the target risk factors and potential mechanism underlying hip OF risk, we further examined this candidate SNP's relevance to hip BMD both in Chinese and Caucasian populations involving 9,962 additional subjects. This SNP was confirmed as consistently associated with hip BMD even across ethnic boundaries, in both Chinese and Caucasians (combined P = 6.39×10−6), further attesting to its potential effect on osteoporosis. ALDH7A1 degrades and detoxifies acetaldehyde, which inhibits osteoblast proliferation and results in decreased bone formation. Our findings may provide new insights into the pathogenesis of osteoporosis

First observation of the decays χcJ→π0π0π0π0

We present a study of the P-wave spin-triplet charmonium χ cJ decays (J=0, 1, 2) into π0π0π0π0. The analysis is based on 106×106 ψ⊃′ decays recorded with the BESIII detector at the BEPCII electron positron collider. The decay into the π0π0π0π0 hadronic final state is observed for the first time. We measure the branching fractions B(χ c0→π0π0π0π0)=(3.34±0. 06±0.44)×10⊃-3, B(χ c1→π0π0π0π0) =(0.57±0.03±0.08)×10⊃-3, and B(χ c2→π0π0π0π0)=(1.21±0.05±0.16) ×10⊃-3, where the uncertainties are statistical and systematical, respectively. © 2011 American Physical Society.published_or_final_versio

Measurement of the matrix element for the decay η′→ηπ +π -

The Dalitz plot of η⊃′→ηπ⊃+π⊃- decay is studied using (225.2±2.8)×106 J/ψ events collected with the BESIII detector at the BEPCII e⊃+e⊃- collider. With the largest sample of η⊃′ decays to date, the parameters of the Dalitz plot are determined in a generalized and a linear representation. Also, the branching fraction of J/ψ→γη⊃′ is determined to be (4.84±0.03±0.24)×10⊃-3, where the first error is statistical and the second systematic. © 2011 American Physical Society.published_or_final_versio

Branching fraction measurements of χc0 and χc2 to π0π0 and ηη

Using a sample of 1.06×108 ψ ′ decays collected by the BESIII detector, χc0 and χc2 decays into π0π0 and ηη are studied. The branching fraction results are Br(χc0→π 0π0)=(3.23±0.03±0.23±0.14)×10 -3, Br(χc2→π0π0)=(8.8±0.2±0.6±0.4)×10 -4, Br(χc0→ηη)=(3.44±0.10±0. 24±0.2)×10 -3, and Br(χc2→ηη)=(6. 5±0.4±0.5±0.3)×10 -4, where the uncertainties are statistical, systematic due to this measurement, and systematic due to the branching fractions of ψ ′→ γχcJ. The results provide information on the decay mechanism of χc states into pseudoscalars. © 2010 The American Physical Society.published_or_final_versio

Identification of PLCL1 Gene for Hip Bone Size Variation in Females in a Genome-Wide Association Study

Osteoporosis, the most prevalent metabolic bone disease among older people, increases risk for low trauma hip fractures (HF) that are associated with high morbidity and mortality. Hip bone size (BS) has been identified as one of the key measurable risk factors for HF. Although hip BS is highly genetically determined, genetic factors underlying the trait are still poorly defined. Here, we performed the first genome-wide association study (GWAS) of hip BS interrogating ∼380,000 SNPs on the Affymetrix platform in 1,000 homogeneous unrelated Caucasian subjects, including 501 females and 499 males. We identified a gene, PLCL1 (phospholipase c-like 1), that had four SNPs associated with hip BS at, or approaching, a genome-wide significance level in our female subjects; the most significant SNP, rs7595412, achieved a p value of 3.72×10−7. The gene's importance to hip BS was replicated using the Illumina genotyping platform in an independent UK cohort containing 1,216 Caucasian females. Two SNPs of the PLCL1 gene, rs892515 and rs9789480, surrounded by the four SNPs identified in our GWAS, achieved p values of 8.62×10−3 and 2.44×10−3, respectively, for association with hip BS. Imputation analyses on our GWAS and the UK samples further confirmed the replication signals; eight SNPs of the gene achieved combined imputed p values<10−5 in the two samples. The PLCL1 gene's relevance to HF was also observed in a Chinese sample containing 403 females, including 266 with HF and 177 control subjects. A SNP of the PLCL1 gene, rs3771362 that is only ∼0.6 kb apart from the most significant SNP detected in our GWAS (rs7595412), achieved a p value of 7.66×10−3 (odds ratio = 0.26) for association with HF. Additional biological support for the role of PLCL1 in BS comes from previous demonstrations that the PLCL1 protein inhibits IP3 (inositol 1,4,5-trisphosphate)-mediated calcium signaling, an important pathway regulating mechanical sensing of bone cells. Our findings suggest that PLCL1 is a novel gene associated with variation in hip BS, and provide new insights into the pathogenesis of HF

Study of a00(980)-f0(980) mixing

Using samples of 2.25×108 J/ψ events and 1.06×108 ψ ′ events collected with the BES III detector, we study the f 0(980)→a00(980) and a00(980)→f 0(980) transitions in the processes J/ψ→φf 0(980) →φa00(980) and χ c1→π0a00(980)→π0f 0(980), respectively. Evidence for f 0(980)→a00(980) is found with a significance of 3.4σ, while in the case of a00(980)→f 0(980) transition, the significance is 1.9σ. Measurements and upper limits of both branching ratios and mixing intensities are determined. © 2011 American Physical Society.published_or_final_versio

Higher-order multipole amplitude measurement in ψ ′→γχ c2

Using 106×106 ψ ′ events collected with the BESIII detector at the BEPCII storage ring, the higher-order multipole amplitudes in the radiative transition ψ ′→γχ c2→γπ +π -/γK +K - are measured. A fit to the χ c2 production and decay angular distributions yields M2=0.046±0. 010±0.013 and E3=0.015±0.008±0.018, where the first errors are statistical and the second systematic. Here M2 denotes the normalized magnetic quadrupole amplitude and E3 the normalized electric octupole amplitude. This measurement shows evidence for the existence of the M2 signal with 4.4σ statistical significance and is consistent with the charm quark having no anomalous magnetic moment. © 2011 American Physical Society.published_or_final_versio

Observation of \chi_{cJ} decaying into the p\bar{p}K^{+}K^{-} final state

First measurements of the decays of the three $\chi_{cJ}$ states to $p\bar{p}K^{+}K^{-}$ final states are presented. Intermediate $\phi\to K^{+}K^{-}$ and $\Lambda(1520)\to pK^{-}$ resonance states are observed, and branching fractions for $\chi_{cJ}\to \bar{p}K^{+}\Lambda(1520)$, $\Lambda(1520) \bar{\Lambda}(1520)$, and $\phi p\bar{p}$ are reported. We also measure branching fractions for direct $\chi_{cJ}\to p\bar{p} K^{+}K^{-}$ decays. These are first observations of $\chi_{cJ}$ decays to unstable baryon resonances and provide useful information about the $\chi_{cJ}$ states. The experiment uses samples of $\chi_{cJ}$ mesons produced via radiative transitions from 106 million $\psi^{\prime}$ mesons collected in the BESIII detector at the BEPCII $e^+e^-$ collider.Comment: 16 pages, 5 figure