450968
Studying the scalar bound states of KK system in Bethe-Salpeter formalism
We study the possible bound states of the KK system in the Bethe-Salpeter formalism in the ladder and instantaneous approximations. We find that the bound states exist. However, these bound states have very small decay widths. Therefore, besides the possible KK component, there may be some other structures in the observed f{sub 0}(980) and a{sub 0}(980)
119271994
$CP$ violation for $B^{0}\rightarrow \rho^{0}(\omega)\rho^{0}(\omega) \rightarrow \pi^+\pi^-\pi^+\pi^-$ in QCD factorization
In the QCD factorization (QCDF) approach we study the direct $CP$ violation in $\bar{B}^{0}\rightarrow\rho^0(\omega)\rho^0(\omega)\rightarrow\pi^+\pi^-\pi^+\pi^-$ via the $\rho-\omega$ mixing mechanism. We find that the $CP$ violation can be enhanced by double $\rho-\omega$ mixing when the masses of the $\pi^+\pi^-$ pairs are in the vicinity of the $\omega$ resonance, and the maximum $CP$ violation can reach 28{\%}. We also compare the results from the naive factorization and the QCD factorization.
119299313
CP violation in $B^{\pm} \rightarrow \pi^{\pm}\pi^{+}\pi^{-}$ in the region with low invariant mass of one $\pi^{+}\pi^{-}$ pair
Recently, the large CP asymmetries in B → πππ decays were found by the LHCb Collaboration to localize in the region m π+π− < 0.4 GeV. We find such large localized CP asymmetries may be due to the interference between a light scalar and ρ(770) intermediate resonances. Consequently, we argue that the distribution of CP asymmetries in the Dalitz plots of three-body B decays could be very helpful for identifying the presence of the scalar resonance.
15163914
Supernova Neutrinos Detection On Earth
In this paper, we first discuss the detection of supernova neutrino on Earth. Then we propose a possible method to acquire information about θ13 smaller than 1.5 ◦ by detecting the ratio of the event numbers of different flavor supernova neutrinos. Such an sensitivity cannot yet be achieved by the Daya Bay reactor neutrino experiment.
13937852
Strong decays of heavy baryons in the Bethe-Salpeter formalism
In this paper we study the properties of diquarks (composed of u and/or d quarks) in the Bethe-Salpeter (BS) formalism under the covariant instantaneous approximation. We calculate their BS wave functions and study their effective interaction with the pion. Using the effective coupling constant among the diquarks and the pion, in the heavy quark limit m{sub Q}{yields}{infinity}, we calculate the decay widths of {sigma}{sub Q}{sup (*)} (Q=c, b) in the BS formalism under the covariant instantaneous approximation and then give predictions of the decay widths {gamma}({sigma}{sub b}{sup (*)}{yields}{lambda}{sub b}+{pi})
119535783
A dynamical mechanism for the hairpin diagram
SummaryBased on the nonvalence quark-antiquark and gluon constituent structure of mesons we give a reasonable dynamical mechanism which can induce the hairpin diagram without violating the well-observed OZI rule. We calculate the hairpin amplitudes of
$$D^0 \to \overline K ^0 \eta $$
 and
$$\overline K ^0 \eta '$$
 normalized by
$$D^0 \to \overline K ^0 \pi ^0 $$
 and have found that the hairpin diagram can give rise to substantial contributions to the decays where a meson with aSU(3) flavor singlet component is involved in the final state. In this scenario, we also obtain the branching ratio of
$$D^0 \to \overline K ^0 \phi $$
 as 0.55% in comparison with the experimental data of 0.83%.
118914273
Direct photon production in a nuclear environment
17569178
Nuclear enhanced power corrections to DIS structure functions
Abstract We calculate nuclear enhanced power corrections to structure functions measured in deeply inelastic lepton–nucleus scattering in Quantum Chromodynamics (QCD). We find that the nuclear medium enhanced power corrections at order of O ( α s / Q 2 ) enhance the longitudinal structure function  F L , and suppress the transverse structure function  F 1 . We demonstrate that strong nuclear effects in σ A / σ D and R A / R D , recently observed by HERMES Collaboration, can be explained in terms of the nuclear enhanced power corrections.
17743185
Nuclear dependence in transverse momentum distribution for Drell-Yan pair
Abstract In terms of multiple scattering picture, I compute the nuclear dependence in Drell-Yan transverse momentum distribution, dσ / dQ 2 dq T 2 , in hadron-nucleus collisions. I present the results for large q T region and discuss the possible suppression in small q T region.
19032960
Transverse momentum broadening due to the multiple scattering
Using the Drell-Yan process in hadron-nucleus collisions and deeply inelastic lepton-nucleus scattering (DIS) as examples, I show that the transverse momentum broadening can be expressed in terms of four-parton correlation functions. I argue that jet broadening in DIS provide an excellent measurement of the four-parton correlation functions and a test of QCD treatment of the multiple scattering.
14220177
Leading Soft Gluon Production in High Energy Nuclear Collisions
The leading soft gluon pT distribution in heavy ion collisions was ob-tained by Kovner, McLerran, and Weigert after solving classical Yang-Mills equations. I show explicitly this result can be understood in terms of conventional QCD perturbation theory. I also demonstrate that the key logarithm in their result represents the logarithm in DGLAP evolution equations.