118695285
Detection of supernova neutrinos on the Earth for large theta13
Supernova (SN) neutrinos detected on the Earth are subject to the shock wave effects, the Mikheyev-Smirnov-Wolfenstein (MSW) effects, the neutrino collective effects and the Earth matter effects. Considering the recent experimental result about the large mixing angle θ13 (⋍ 8.8 ) provided by the Daya Bay Collaboration and applying the available knowledge for the neutrino conversion probability in the high resonance of SN, PH , which is in the form of hypergeometric function in the case of large θ13, we deduce the expression of PH taking into account the shock wave effects. It is found that PH is not zero in a certain range of time due to the shock wave effects. After considering all the four physical effects and scanning relevant parameters, we calculate the event numbers of SN neutrinos detected at the Daya Bay experiment. From the numerical results, it is found that the behaviors of neutrino event numbers detected on the Earth depend on the neutrino mass hierarchy and neutrino spectrum parameters including the temperature Tα, the dimensionless pinching parameter ηα or βα (where α refers to neutrino flavor), the average energy 〈Eα〉, and the SN neutrino luminosities Lα. We also compare the results of two parametrization methods for the neutrino energy distributions and give the ranges of SN neutrino event numbers that will be detected at the Daya Bay experiment.
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.
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%.
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})
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.
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.
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.
118936305
Multiple scattering and energy loss in semi-inclusive deeply inelastic eA scattering
We calculate the multiple scattering effect on single hadron production in semi-inclusive lepton-nucleus deeply inelastic scattering. We show that the quantum interference of multiple scattering amplitudes leads to suppression in hadron productions. At the leading power in medium length, the suppression can be approximately expressed in terms of a shift in $z$ of the fragmentation function $D(z)$, and could be therefore interpreted as the collisional energy loss. We compare our calculation with existing experimental data. We also discuss the effect of quark mass on the suppression. Our approach can be extended to other observables in hadronic collisions.
13900650
Nuclear dependence in the Drell-Yan transverse momentum distribution
We calculate the nuclear enhancement in the Drell-Yan transverse momentum distribution in hadron-nucleus collisions. In terms of the multiple scattering picture, we compute the contributions from double scattering. Applying the generalized factorization theorem, we express the nuclear enhancement in terms of twist-4 nuclear parton correlation functions. Using the known information on these twist-4 parton correlation functions, we estimate the nuclear enhancement for Drell-Yan pairs in the large q{sub T} region. We also discuss the source of nuclear suppression in the small q{sub T} region. {copyright} {ital 1998} {ital The American Physical Society}