ترغب بنشر مسار تعليمي؟ اضغط هنا

Partial wave analysis of J/psi to gamma phi phi

110   0   0.0 ( 0 )
 نشر من قبل Beijiang Liu
 تاريخ النشر 2008
  مجال البحث
والبحث باللغة English
 تأليف BES Collaboration




اسأل ChatGPT حول البحث

Using $5.8 times 10^7 J/psi$ events collected in the BESII detector, the radiative decay $J/psi to gamma phi phi to gamma K^+ K^- K^0_S K^0_L$ is studied. The $phiphi$ invariant mass distribution exhibits a near-threshold enhancement that peaks around 2.24 GeV/$c^{2}$. A partial wave analysis shows that the structure is dominated by a $0^{-+}$ state ($eta(2225)$) with a mass of $2.24^{+0.03}_{-0.02}{}^{+0.03}_{-0.02}$ GeV/$c^{2}$ and a width of $0.19 pm 0.03^{+0.06}_{-0.04}$ GeV/$c^{2}$. The product branching fraction is: $Br(J/psi to gamma eta(2225))cdot Br(eta(2225)to phiphi) = (4.4 pm 0.4 pm 0.8)times 10^{-4}$.


قيم البحث

اقرأ أيضاً

Based on a sample of $2.25times 10^{8}$ $J/psi$ events collected with the BESIII detector at BEPCII, a full partial wave analysis on $J/psitogammaetaeta$ was performed using the relativistic covariant tensor amplitude method. The results show that th e dominant $0^{++}$ and $2^{++}$ components are from the $f_0(1710)$, $f_0(2100)$, $f_0(1500)$, $f_2(1525)$, $f_2(1810)$ and $f_2(2340)$. The resonance parameters and branching fractions are also presented.
The first full amplitude analysis of $B^+to J/psi phi K^+$ with $J/psitomu^+mu^-$, $phito K^+K^-$ decays is performed with a data sample of 3 fb$^{-1}$ of $pp$ collision data collected at $sqrt{s}=7$ and $8$ TeV with the LHCb detector. The data canno t be described by a model that contains only excited kaon states decaying into $phi K^+$, and four $J/psiphi$ structures are observed, each with significance over $5$ standard deviations. The quantum numbers of these structures are determined with significance of at least $4$ standard deviations. The lightest has mass consistent with, but width much larger than, previous measurements of the claimed $X(4140)$ state. The model includes significant contributions from a number of expected kaon excitations, including the first observation of the $K^{*}(1680)^+tophi K^+$ transition.
The first observation of exotic states with a new quark content $c bar{c} u bar{s}$ decaying to the $J/psi K^+$ final state is reported with high significance from an amplitude analysis of the $B^+ to J/psi phi K^+$ decay. The analysis is carried out using proton-proton collision data corresponding to a total integrated luminosity of 9 fb$^{-1}$ collected by the LHCb experiment at centre-of-mass energies of 7, 8 and 13 TeV. The most significant state, $Z_{cs}(4000)^+$, has a mass of $4003pm6,^{+,phantom{0}4}_{-,14}$ MeV, a width of $131pm15pm26$ MeV, and spin-parity $J^P=1^+$, where the quoted uncertainties are statistical and systematic, respectively. A new $1^+$ $X(4685)$ state decaying to the $J/psi phi$ final state is also observed with high significance. In addition, the four previously reported $J/psi phi$ states are confirmed and two more exotic states, $Z_{cs}(4220)^+$ and $X(4630)$, are observed with significance exceeding five standard deviations.
The $B_s^0 rightarrow J/psi phi phi$ decay is observed in $pp$ collision data corresponding to an integrated luminosity of 3 fb$^{-1}$ recorded by the LHCb detector at centre-of-mass energies of 7 TeV and 8 TeV. This is the first observation of this decay channel, with a statistical significance of 15 standard deviations. The mass of the $B_s^0$ meson is measured to be $5367.08,pm ,0.38,pm, 0.15$ MeV/c$^2$. The branching fraction ratio $mathcal{B}(B_s^0 rightarrow J/psi phi phi)/mathcal{B}(B_s^0 rightarrow J/psi phi)$ is measured to be $0.0115,pm, 0.0012, ^{+0.0005}_{-0.0009}$. In both cases, the first uncertainty is statistical and the second is systematic. No evidence for non-resonant $B_s^0 rightarrow J/psi phi K^+ K^-$ or $B_s^0 rightarrow J/psi K^+ K^- K^+ K^-$ decays is found.
Using $1.06times10^8$ $psi(3686)$ events recorded in $e^{+}e^{-}$ collisions at $sqrt{s}=$ 3.686 GeV with the BESIII at the BEPCII collider, we present searches for C-parity violation in $J/psi to gammagamma$ and $ gamma phi$ decays via $psi(3686) to J/psi pi^+pi^-$. No significant signals are observed in either channel. Upper limits on the branching fractions are set to be $mathcal{B}(J/psi to gammagamma) < 2.7 times 10^{-7}$ and $mathcal{B}(J/psi to gammaphi) < 1.4 times 10^{-6}$ at the 90% confidence level. The former is one order of magnitude more stringent than the previous upper limit, and the latter represents the first limit on this decay channel.
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