ترغب بنشر مسار تعليمي؟ اضغط هنا

Study of Jpsi decaying into omega p bar p

160   0   0.0 ( 0 )
 نشر من قبل Beijiang Liu
 تاريخ النشر 2007
  مجال البحث
والبحث باللغة English
 تأليف BES Collaboration




اسأل ChatGPT حول البحث

The decay $J/psi to omega p bar p$ is studied using a $5.8 times 10^7$ $J/psi$ event sample accumulated with the BES II detector at the Beijing electron-positron collider. The decay branching fraction is measured to be $B(J/psi to omega p bar p)=(9.8pm 0.3pm 1.4)times 10^{-4}$. No significant enhancement near the $pbar p$ mass threshold is observed, and an upper limit of $B(J/psi to omega X(1860))B(X(1860)to pbar p)$$ $$< 1.5 times 10^{-5}$ is determined at the 95% confidence level, where X(1860) designates the near-threshold enhancement seen in the $pbar p$ mass spectrum in $J/psi to gamma p bar p$ decays.



قيم البحث

اقرأ أيضاً

The decay $J/psi rightarrow omega p bar{p}$ has been studied, using $225.3times 10^{6}$ $J/psi$ events accumulated at BESIII. No significant enhancement near the $pbar{p}$ invariant-mass threshold (denoted as $X(pbar{p})$) is observed. The upper limi t of the branching fraction $mathcal{B}(J/psi rightarrow omega X(pbar{p}) rightarrow omega p bar{p})$ is determined to be $3.9times10^{-6}$ at the 95% confidence level. The branching fraction of $J/psi rightarrow omega p bar{p}$ is measured to be $mathcal{B}(J/psi rightarrow omega p bar{p}) =(9.0 pm 0.2 (text{stat.})pm 0.9 (text{syst.})) times 10^{-4}$.
We search for high-mass resonances decaying into Z boson pairs using data corresponding to 6 fb^-1 collected by the CDF experiment in pbar{p} collisions at sqrt{s}=1.96 TeV. The search is performed in three distinct final states: ZZ --> l^+l^-l^+l^-, ZZ --> l^+l^- u u, and ZZ --> l^+l^-jj. For a Randall-Sundrum graviton G*, the 95% CL upper limits on the production cross section times branching ratio to ZZ, sigma(pbar{p} --> G^* --> ZZ), vary between 0.26 pb and 0.045 pb in the mass range 300 < M_{G*} < 1000 GeV/c^2.
The spin density matrix of the $omega$ has been determined for the reaction $bar{p} p , rightarrow , omega pi^0$ with unpolarized in-flight data measured by the Crystal Barrel LEAR experiment at CERN. The two main decay modes of the $omega$ into $pi^ 0 gamma $ and $pi^+ pi^- pi^0$ have been separately analyzed for various $bar{p}$ momenta between 600 and 1940 MeV/c. The results obtained with the usual method by extracting the matrix elements via the $omega$ decay angular distributions and with the more sophisticated method via a full partial wave analysis are in good agreement. A strong spin alignment of the $omega$ is clearly visible in this energy regime and all individual spin density matrix elements exhibit an oscillatory dependence on the production angle. In addition, the largest contributing orbital angular momentum of the $bar{p}p$ system has been identified for the different beam momenta. It increases from $L^{max}_{bar{p}p}$ = 2 at 600 MeV/c to $L^{max}_{bar{p}p}$ = 5 at 1940 MeV/c.
96 - K. Chu , M.-Z. Wang , I. Adachi 2019
Using a data sample of $772 times 10^6$ BB pairs collected on the ${Upsilon}(4S)$ resonance with the Belle detector at the KEKB asymmetric-energy $e^+e^-$ collider, we report the observations of $B^0to p{bar p}pi^+pi^-$ and $B^+ to p{bar p}pi^+pi^0$. We measure a decay branching fraction of $(0.83 pm 0.17 pm 0.17) times 10^-6$ in $B^0to p{bar p}pi^+pi^-$ for $M_{pi^+pi^-} < 1.22 GeV/c^2$ with a significance of 5.5 standard deviations. The contribution from $B0 to p{bar p}K^0$ is excluded. We measure a decay branching fraction of $(4.58 pm 1.17 pm 0.67) times 10^-6$ for $B^+ to p{bar p}pi^+pi^0$ with $M_{pi^+pi^0} < 1.3 GeV/c^2$ with a significance of 5.4 standard deviations. We study the difference of the $M_{p{bar p}}$ distributions in $B^0to p{bar p}pi^+pi^-$ and $B^+ to p{bar p}pi^+pi^0$.
Using a data sample of 106 million $psi(3686)$ events collected with the BESIII detector operated at the BEPCII storage ring, we study for the first time the decay $chi_{cJ}tophi K^{0}_S K^{pm}pi^{mp}$ and $chi_{cJ}tophi K^{+} K^{-}pi^{0}$ in the E1 radiative transition $psi(3686)togammachi_{cJ}$. The decays are dominated by the three-body decay $chi_{cJ}to phi K^*(892)bar{K}$. We measure branching fractions for this reaction via the neutral and charged $K^*(892)$ and find them consistent with each other within the expectation of isospin symmetry. In the $Kbar{K}pi$ invariant mass distribution a structure near the $K^*(892)bar{K}$ mass threshold is observed, and the corresponding mass and width are measured to be $1412pm4(mathrm{stat.})pm8(mathrm{sys.}) mathrm{MeV}/c^2$ and $Gamma$ = $84pm12(mathrm{stat.})pm40(mathrm{sys.}) mathrm{MeV}$, respectively. The observed state favors an assignment to the $h_1(1380)$, considering its possible $J^{PC}$ and comparing its mass, width and decay mode to those reported in the Particle Data Group.
التعليقات
جاري جلب التعليقات جاري جلب التعليقات
سجل دخول لتتمكن من متابعة معايير البحث التي قمت باختيارها
mircosoft-partner

هل ترغب بارسال اشعارات عن اخر التحديثات في شمرا-اكاديميا