118409577
Proton Sea Quark Flavour Asymmetry and Roper Resonance
We study the proton and the Roper resonance together with the meson cloud model, by constructing a Hamiltonian matrix and solving the eigenvalue equation. The proton sea quark flavour asymmetry and some properties of the Roper resonance are thus reproduced in one scheme.
118631589
Sea quark flavor asymmetry of hadrons in statistical balance model
We suggested a Monte Carlo approach to simulate a kinetic equilibrium ensemble, and proved the equivalence to the linear equations method on equilibrium. With the convenience of the numerical method, we introduced variable splitting rates representing the details of the dynamics as model parameters which were not considered in previous works. The dependence on model parameters was studied, and it was found that the sea quark flavor asymmetry weakly depends on model parameters. It reflects the statistics principle, contributes the dominant part of the asymmetry, and the effect caused by details of the dynamics is small. We also applied the Monte Carlo approach of the statistical model to predict the theoretical sea quark asymmetries in kaons, octet baryons $\ensuremath{\Sigma}$, $\ensuremath{\Xi}$, and $\ensuremath{\Delta}$ baryons, even in exotic pentaquark states.
14130582
Multiple reference states and complete spectrum of the Zn Belavin model with open boundaries
The multiple reference state structure of the Zn Belavin model with non-diagonal boundary terms is discovered. It is found that there exist n reference states, each of them yields a set of eigenvalues and Bethe Ansatz equations of the transfer matrix. These n sets of eigenvalues together constitute the complete spectrum of the model. In the quasi-classic limit, they give the complete spectrum of the corresponding Gaudin model.
118481043
The D0 Dimuon Charge Asymmetry and Baryon Asymmetry of the Universe
The D0 collaboration has reported a 3.2 \sigma deviation from the Standard Model (SM) prediction in the like-sign dimuon charge asymmetry. New physics beyond the SM in B_s - \bar B_s mixing is needed to explain the data. In this paper, we investigate the possible extension of the SM with one generation color-triplet charged scalar as well as three generation Majorana fermions. We study the implications of the model on the D0's dimuon charge asymmetry as well as matter anti-matter asymmetry of the Universe.
119300744
TeV scale universal seesaw, vacuum stability and heavy Higgs
A bstractWe discuss the issue of vacuum stability of standard model by embedding it within the TeV scale left-right universal seesaw model (called SLRM in the text). This model has only two coupling parameters (λ1, λ2) in the Higgs potential and only two physical neutral Higgs bosons (h, H). We explore the range of values for (λ1, λ2) for which the light Higgs boson mass Mh = 126 GeV and the vacuum is stable for all values of the Higgs fields. Combining with the further requirement that the scalar self couplings remain perturbative till typical GUT scales of order 1016 GeV, we find (i) an upper and lower limit on the second Higgs (H) mass to be within the range: 0.4 ≤ $ \frac{{{M_H}}}{{{v_R}}} $ ≤ 0.7, where the vR is the parity breaking scale and (ii) that the heavy vector-like top, bottom and τ partner fermions (P3, N3, E3) mass have an upper bound $ {M_{{{P_3},}}}_{{{N_3},{E_3}}}\leq {v_R} $. We discuss some phenomenological aspects of the model pertaining to LHC.
118561664
Thermodynamics of Black Holes in Massive Gravity
We present a class of charged black hole solutions in an (n + 2)-dimensional massive gravity with a negative cosmological constant, and study thermodynamics and phase structure of the black hole solutions both in grand canonical ensemble and canonical ensemble. The black hole horizon can have a positive, zero or negative constant curvature characterized by constant k. By using Hamiltonian approach, we obtain conserved charges of the solutions and nd black hole entropy still obeys the area formula and the gravitational eld equation at the black hole horizon can be cast into the rst law form of black hole thermodynamics. In grand canonical ensemble, we nd that thermodynamics and phase structure depends on the combination k 2 =4 +c2m 2 in the four dimensional case, where is the chemical potential and c2m 2 is the coecient of the second term in the potential associated with graviton mass. When it is positive, the Hawking-Page phase transition can happen, while as it is negative, the black hole is always thermodynamically stable with a positive capacity. In canonical ensemble, the combination turns out to be k +c2m 2 in the four di
35611437
Top quark forward-backward asymmetry in the little Higgs model
A sizable difference in top quark pair forward backward asymmetry (AFB) is observed at Tevatron. The discrepancy triggers many new physics beyond the standard model (SM) and then constrains the parameter spaces in them. In this article we calculate the AFB of the top-pair production at Tevatron up to next to leading order (NLO) in the little Higgs model (LHM). We find that the contribution of ZH can be large enough to make up the gap between SM prediction and experimental data. Then, the parameter space for the couplings between ZH and quarks are constrained. Thus, this model can fulfill the experimental data, both in AFB and in cross section.