We compute sea quark Sivers distribution within color glass condensate(CGC) framework. It has been found that up to the leading logarithm accuracy, the collinear twist-3 approach and the CGC calculation yield the same result for sea quark Sivers distribution in the dilute limit. We further verify that transverse momentum dependent factorization is consistent with CGC treatment at small x for the case of transverse spin asymmetry in open charm quark production in semi-inclusive deeply inelastic scattering process in an overlap kinematical region.PACS numbers: I. INTRODUCTIONPolarization dependent phenomenology at small x has attracted a lot of attentions in recent years, as it plays an important role in studying gluon tomography of nucleon/nuclei. Employing powerful color glass condensate(CGC) effective theory [1] and transverse momentum dependent(TMD) factorization [2,3] to polarization effects at small x has produced fruitful results. Among various topical issues in small x spin physics, small x parton helicity distributions [4,5], linearly polarization of small x gluons [6][7][8][9][10][11][12][13][14], (for a recent review covering this topic, see [15]), spin independent odderon [16][17][18] and spin dependent odderon [19][20][21], and elliptical gluon distribution [22][23][24][25][26] were most extensively investigated recently. In this paper, we further explore the phenomenological consequence of spin dependent odderon.In perturbative QCD, odderon is a color-singlet exchange and can be formed by three gluons in a symmetric color state. In the saturation regime, the expectation value of odderon that incorporates multiple gluon exchange effect has been computed in the MV model [1] with a cubic term [27]. The energy dependence of the odderon exchange is described by the BKP equation [28], which also can be formulated in the dipole model [29] and CGC framework [30,31]. It was found in Ref.[19] that a spin dependent odderon can be induced by an asymmetric color source distribution (i.e. valence quark distribution in the context of the MV model) in the transverse plane of a transversely polarized nucleon [32][33][34]. To be more precise, transverse momentum transferred through spin dependent odderon is correlated with transverse spin of target. In a more recent work [20], three T-odd gluon TMDs are shown to be identical and related to the spin dependent odderon. It turns out that the spin dependent odderon is the only possible source contributing to transverse single spin asymmetries(SSAs) at small x in the context of TMD factorization and CGC framework.During the past few decades, transverse single spin asymmetries in high energy scattering is one of the major focus in hadron physics studies. It not only poses the great theoretical challenge to account for the observed large SSAs, but also offers us opportunities to address some central aspects of hadron physics, such as the universality issue associated with QCD factorization theorem, and parton orbital angular momentum inside nucleon. Depending on kinematical r...

No abstract

To sum high-energy leading logarithms in a consistent way, one has to impose the strong ordering in both projectile rapidity and dense target rapidity simultaneously, which results in a kinematically improved Balitsky-Kovchegov(BK) equation. We find that beyond this strong ordering region, the important sub-leading double logarithms arise at high order due to the incomplete cancellation between real corrections and virtual corrections in a t-channel calculation. Based on this observation, we further argue that these double logarithms are the Sudakov type ones, and thus can be resummed into an exponential leading to a Sudakov suppressed BK equation.

We investigate the double-charm and hidden-charm hexaquarks as molecules in the framework of the one-boson-exchange potential model. The multichannel coupling and S − D wave mixing are taken into account carefully. We adopt the complex scaling method to investigate the possible quasibound states, whose widths are from the three-body decay channel ΛcΛcπ or Λc Λcπ. For the double-charm system of I(J P ) = 1(1 + ), we obtain a quasibound state, whose width is 0.50 MeV if the binding energy is -14.27 MeV. And the S-wave ΛcΣc and ΛcΣ * c components give the dominant contributions. For the 1(0 + ) double-charm hexaquark system, we do not find any pole. We find more poles in the hidden-charm hexaquark system. We obtain one pole as a quasibound state in the I G (J P C ) = 1 + (0 −− ) system, which only has one channel (Λc Σc + Σc Λc)/ √ 2. Its width is 1.72 MeV with a binding energy of -5.37 MeV. But, we do not find any pole for the scalar 1 − (0 −+ ) system. For the vector 1 − (1 −+ ) system, we find a quasibound state. Its energies, widths and constituents are very similar to those of the 1(1 + ) double-charm case. In the vector 1 + (1 −− ) system, we get two poles-a quasibound state and a resonance. The quasibound state has a width of 0.6 MeV with a binding energy of -15.37 MeV. For the resonance, its width is 2.72 MeV with an energy of 63.55 MeV relative to the Λc Σc threshold. And its partial width from the two-body decay channel (Λc Σc − Σc Λc)/ √ 2 is apparently larger than the partial width from the three-body decay channel Λc Λcπ. Especially, the 1 + (0 −− ) and 1 − (1 −+ ) hidden-charm hexaquark molecular states are very interesting. These isovector mesons have exotic J P C quantum numbers which are not accessible to the conventional q q mesons. ( * ) c and Λ c Σ( * ) c channels in the molecule picture. As pointed out in our previous work [61], the cross diagram DD * ↔ D * D of the one-pion-exchange will provide a complex potential, which is from the three-body decay effect. This behavior

No abstract

No abstract

We introduce a modified Balitskii-Fadin-Kuraev-Lipatov (BFKL) equation with the rapidity veto that originates from external kinematic constraint. Though it is a formally sub-leading power contribution, such kinematic effect becomes very important especially in the threshold region, where there is no sufficient phase space for the small x evolution to be fully developed. We also investigate the phenomenological consequences of the kinematic constraint BFKL equation in the forward particle production processes in pp and eA collisions. It is shown that particle yield at large transverse momentum is significantly suppressed in the threshold region.