ترغب بنشر مسار تعليمي؟ اضغط هنا

Lattice QCD study of the heavy-heavy-light quark potential

171   0   0.0 ( 0 )
 نشر من قبل Arata Yamamoto
 تاريخ النشر 2008
  مجال البحث
والبحث باللغة English




اسأل ChatGPT حول البحث

We study the heavy-heavy-light quark ($QQq$) potential in SU(3) quenched lattice QCD, and discuss one of the roles of the finite-mass valence quark in the inter-quark potential. Monte Carlo simulations are performed with the standard gauge action on the $16^4$ lattice at $beta =6.0$ and the $O(a)$-improved Wilson fermion action at four hopping parameters. For statistical improvement, the gauge configuration is fixed with the Coulomb gauge. We calculate the potential energy of $QQq$ systems as a function of the inter-heavy-quark distance $R$ in the range of $R le$ 0.8 fm. The $QQq$ potential is well described with a Coulomb plus linear potential, and the effective string tension between the two heavy quarks is significantly smaller than the string tension $sigma simeq 0.89$ GeV/fm. It would generally hold that the effect of the finite-mass valence quark reduces the inter-two-quark confinement force in baryons.



قيم البحث

اقرأ أيضاً

We report progress towards computing the heavy quark momentum diffusion coefficient from the correlator of two chromo-electric fields attached to a Polyakov loop in pure SU(3) gauge theory. Using a multilevel algorithm and tree-level improvement, we study the behavior of the diffusion coefficient as a function of temperature in the wide range $1.1 < T / T_c < 10^4$ in order to compare it to perturbative expansions at high temperature. We find that within errors the lattice results are remarkably compatible with the next-to-leading order perturbative result.
We perform the first study about the heavy-heavy-light quark potential in lattice QCD and a potential model. We find that the inter-two-quark confining force is reduced by valence quark motional effects compared to the string tension.
We compute charm and bottom quark masses in the quenched approximation and in the continuum limit of lattice QCD. We make use of a step scaling method, previously introduced to deal with two scale problems, that allows to take the continuum limit of the lattice data. We determine the RGI quark masses and make the connection to the MSbar scheme. The continuum extrapolation gives us a value m_b^{RGI} = 6.73(16) GeV for the b-quark and m_c^{RGI} = 1.681(36) GeV for the c-quark, corresponding respectively to m_b^{MSbar}(m_b^{MSbar}) = 4.33(10) GeV and m_c^{MSbar}(m_c^{MSbar}) = 1.319(28) GeV. The latter result, in agreement with current estimates, is for us a check of the method. Using our results on the heavy quark masses we compute the mass of the Bc meson, M_{Bc} = 6.46(15) GeV.
In previous works we predicted the existence of a $bar b bar b u d$ tetraquark with quantum numbers $I(J^P) = 0(1^+)$ using the static approximation for the $bar b$ quarks and neglecting heavy spin effects. Since the binding energy is of the same ord er as expected for these heavy spin effects, it is essential to include them in the computation. Here we present a corresponding method and show evidence that binding is only slightly weakened and that the $bar b bar b u d$ tetraquark persists.
313 - Y. Namekawa 2009
Heavy-light meson system is investigated using the relativistic heavy quark action on the 2+1 dynamical flavor PACS-CS configurations at the lattice spacing $a^{-1}=2.2$ GeV and the spatial extent L=3 fm. Dynamical up-down and strange quark masses as well as the valence charm quark mass are set around their physical values. We measure the charm-$ud$ and charm-strange meson masses and decay constants. Our results are consistent with the experimental values except the hyperfine splitting of the charm-strange meson. We also estimate the CKM matrix elements in the second row.
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