Lepton-number-violating decays of singly-charged Higgs bosons in the type-(Ⅰ+Ⅱ) seesaw model

The lepton-number-violating decays of singly-charged Higgs bosons H± are investigated in the minimal type-(Ⅰ+Ⅱ) seesaw model with one SU(2)L Higgs triplet Δ and one heavy Majorana neutrino N1 at the TeV scale.We find that the branching ratios B(H+ → lα+ ν)(for α = e,μ,τ) depend not only on the mass and mixing parameters of three light neutrinos νi(for i=1,2,3) but also on those of N1.Assuming that the mass of N1 lies in the range of 200 GeV to 1 TeV,we figure out the generous interference bands for the contributions of νi and N1 to B(H+ →lα+ ν).We illustrate some salient features of such interference effects by considering three typical mass patterns of νi,and show that the relevant Majorana CP-violating phases can affect the magnitudes of B(H+ →l+αν) in this parameter region.     

Charged Higgs Pair Production in a General Two Higgs Doublet Model at e^＋e^- and μ^＋μ^- Linear Colliders

In this paper, charged Higgs pair production through l^＋l^- → H^＋ H^-, where l = e or μ, is studied within the framework of a general Two Higgs Doublet Model （2HDM）. The analysis is relevant to a future e^＋e^- or μ^＋ μ^- collider operating at center of mass energy of √s = 500 GeV. Two different scenarios of small and large a values are studied. Here a is the parameter, which diagonMizes the neutral CP-even Higgs boson mass matrix. Within the Minimal Supersymmetric Standard Model （MSSM）, cross section of this process is almost the same at e＋ e- and #＋#- colliders. It is shown that at e^＋e^- eolliders within a general 2HDM, cross section is not sensitive to the mass of neutral Higgs bosons, however, it can acquire large values up to several picobarn at μ^＋μ^- colliders with the presence of heavy neutral Higgs bosons. A scan over Higgs boson mass parameter space is performed to analyze the effect of large masses of neutral Higgs bosons involved in the s-channel propagator and thus in the total cross section of this process.     

Bounce-averaged Pitch-angle Diffusion by Electromagnetic Ion Cyclotron Waves in Multi-ion Plasmas

We present a study on the gyroresonant interaction particles in multi-ion （H^＋, He^＋, and O^＋） plasmas between electromagnetic ion cyclotron waves and ring current We provide a first evaluation of the bounce-averaged pitch angle diffusion coefficient 〈Dαα〉 for three typical energies of 50, 100 and 150keV at L ≈ 3.5, the heart of the symmetrical ring current. We show that in the H^＋-band and He^＋-band, 〈Dαα〉 can approach - 10^-4 s^-1 for ion H^＋, and - 5 × 10^-5 s^-1 /or ion He^＋; meanwhile, in the O^＋-band, 〈Dαα〉 can reach - 10^-5 s^-1 for ions He^＋ and O^＋. The results above show that the EMIC wave can efficiently produce precipitation loss of energetic （- 100 keV） ions （H^＋, He^＋ and even O^＋）, and such a wave tends to be a serious candidate responsible for the ring current decay.     

Single Production of Top Quark via e-γ Collision in Left-Right Twin Higgs Model

In the context of the left-right twin Higgs （LRTH） model, we fist study single production of the standard model （SM） top quark via e-γ collisions. We find that the corrections of the LRTH model to the cross section of the process e-γ→vebt might be observed only for f ≤750 GeV and the heavy top quark mass scale M ≥500 GeV in future high energy linear e^＋e^- collider （LC） experiment with the center-of-mass （CM） energy √s = 500 GeV and a yearly integrated luminosity of ￡ = 100 fb^-1. We also consider single production of the heavy top quark T via e-γ collisions. Our numerical results show that the possible signals of the heavy top quark T might be observed via the decay channel T →Ф^＋b→tbb in future LC experiment with √s = 3 TeV and ￡ = 500 fb^-1.     

Large Number, Dark Matter, Dark Energy, and Superstructures in the Universe

Since there may exist dark matter particles ν and δ with mass - 10^-1 e V in the universe, the superstructures with a scale of 10^19 solar masses （large number A - 10^19） appeared during the era near and before the hydrogen recombination. Since there are superstructures in the universe, there may be no necessity for the existence of dark energy. For checking the superstructure in the universe by CMB anisotropy, we need to measure CMB angular power spectrum especially around ten degrees across the sky- in more details, While neutrino u is related to electroweak unification, the fourth stable elementary particle 6 may be related to strong-gravity unification, which suggests p ＋ p^- → n ＋ δ^- and that some new baryons appeared in the TeV region.     

Lepton Flavor Violating Z →lIlJ in SO（3） Gauge Extension of SM

The SO（3） gauge extension of SM, which is proposed to present a successful explanation for the observed small masses of neutrino and the nearly tri-bimaximal neutrino mixing, predicted the vector-like SO（3） triplet Majorana neutrinos and SUL（2） double Higgs bosons. In this work we calculate branching ratios of the charged lepton flavor violating decays lIlJV （V = γ, Z） induced by these Majorana neutrinos and Higgs bosons. We find that under the model parameters constrained by experimental bounds on the decays Z →lIlJ, the branching ratio of decays lI→lJγ can be up to 10^-10, which may be accessible at the future experiments.     

Production of Charged Higgs Bosons from Left-Right Twin Higgs Model at TeV Energy e-γ Colliders

The left-right twin Higgs （LRTH） model predicts the existence of three additional Higgs bosons： one neutral Higgs φo and a pair of charged Higgs bosons φ±. In this paper, we study two pair production processes of these new particles at the next generation eγ colliders, i.e., e-γ → e-φ＋φ- , and e-γ→vRφ-φ0. We find that the production cross section of the process e-γ → e-φ＋φ- are at the level of several tens fb, the production cross section of the process e-γ→vRφ-φ0 can reach 0.35 fb with the reasonable parameter values. As long as the charged Higgs bosons are not too heavy, we conclude that these processes might be used to test for the left-right twin Higgs model in future high-energy linear collider experiments.     

Production of Charged Scalars from the Littlest Higgs Model Associated with Top Quark at LHC

The littlest Higgs （LH） model is the most economical one among various little Higgs models, which predicts the existence of the charged scalars Φ^±. In this paper, we study the production of the charged Higgs boson Φ^- with single top quark via the process gb →tΦ^- at the CERN Large Hadron Collider （LHC）. The numerical results show that the production cross section is sma/ler than 0.2 pb in most of the parameters space, it is very difficult to observe the signatures of the charged scalars via the process pp → gb ＋ X → tΦ^- ＋ X at the LHC experiments. However, it can open a window to distinguish the top-pions in the TC2 model or charged Higgs in the MSSM from Φ^±.     

Combined fit to BABAR and Belle Data on e^＋e^- →φπ^＋π^- and φf0（980）

A combined fit is performed to the BABAR and Belle measurements of the e^＋e^- →φπ^＋π^- and φf0（980） cross sections for center-of-mass energy between threshold and 3.0 GeV. The resonance parameters of the φ（1680） and Y（2175） are determined. The mass is （1681-12^＋10） MeV/c^2 and the width is （221-24^＋34） MeV/c^2 for the φ（1680）, and the mass is （2117-49^＋59） MeV/c^2 and the width is （164-80^＋69） MeV/c^2 for the Y（2175）. This information will shed light on the understanding of the nature of the excited φ and Y states observed in e＋e- annihilation.     

News on PHOTOS Monte Carlo： γ＊→π^＋π^-（γ） and K^±→π^＋π^-e^±υ（γ）

PHOTOS Monte Carlo is widely used for simulating QED effects in decay of intermediate particles and resonances. It can be easily connected to other main process generators. In this paper we consider decaying processes γ＊→π^＋π^-（γ） and K^±→π^＋π^-e^±υ（γ） in the framework of Scalar QED. These two processes are interesting not only for the technical aspect of PHOTOS Monte Carlo, but also for precision measurement of αED（Mz）, g--2, as well as ππ scattering lengths.     

Masses and Widths of Light Scalar Mesons in Chiral Perturbation Theory

Based on the diquark model, we assume that the light scalar mesons are q^2q^-2 states rather than qq^-. The chiral effective Lagrangian for the light scalar meson is constructed, and the mass relations are obtained： the isotriplet （a0） and the isosinglet （f0） are the heaviest and are degenerate, the isodoublets （κ） are heavier and the other isosinglet （σ） is the lightest; and 2Mκ^2 = Mα0^2＋ Mσ^2. Using experimental value for a0 and σ mass, we obtain Mκ=794 MeV, which is consistent with the experimental value. Then taking Г（a0^0 →ηπ^0） = 90 MeV and Г（f0→π^0π^0） = 20 MeV, we get the width of σ is： Г（σ0→π^＋π^-）= 150 MeV.     

B→K0^＊（1430）K Decays in Perturbative QCD Approach

In this article, we calculate the branching ratios of B→K0^＊ （1430）K decays by employing the pertur-bative QCD （pQCD） approach at leading order. We perform the evaluations in the two scenarios for the scalar meson spectrum. We find that （i） The leading order pQCD predictions for the branching ratio Br（B^＋→K^＋K0^＊（1430）^0）are in good agreement with the experimental upper limit in both scenarios, while the pQCD predictions for other considered B→K0^＊（1430）K decay modes are also presented and will be tested by the LHC experiments; （ii） The annihilation contributions play an important role in these considered decays, for B^0→K0^＊（1430）^±K^± decays,for example,which are found to be （1-4）×10^-6.     

Radiative Decays of （0^＋, 1^＋） Strange-Bottom Mesons

In this article, we assume that the （0^＋,1^＋） strange-bottom mesons are the conventional bs mesons, and calculate the electromagnetic coupling constants d, g1, g2, and g3 using the light-cone QGD sum rules. Then we study the radiative decays Bs0→Bs^＊γ, Bs1→Bsγ, Bs1→Bs^＊γ, and Bs1→Bs0γ, and observe that the widths are rather narrow. We can search for the （0^＋, 1^＋） strange-bottom mesons in the invariant Bsπ^0 and Bs^＊π^0 mass distributions in the strong decays or in the invariant Bs^＊γ, and Bsγ mass distributions in the radiative decays.     

New Physics Effects on Rare Decays Bu^＋ → π^＋e^＋e^-, ρ^＋e^＋e^- in a Top Quark Two-Higgs-Doublet Model

Using the form factors from light-cone sum rules, we study the branching ratios and forward-backward asymmetries （FBAs） of the exclusive decays Bu^＋→π^＋e^＋e^- and Bu^＋ →ρ^＋e^＋e^- （e= e,μ） in the standard model （SM） and the top quark two-Higgs-doublet model （T2HDM）. From the numerical results, we find that the new physics contributions cannot provide very large enhancement to the branching ratios and the theoretical predictions are in good agreement with the SM ones. The T2HDM effects on FBAs of these decays are small. Precision measurements of the dilepton invariant mass distributions, especially in the lower dilepton mass region, and the FBAs in the decays Bu^＋ → π^＋ （ρ^＋ ）e^＋ e^- will greatly help in discriminating among the SM and the new physics models.     

Excitation Transfer for K2 in High-Lying States by N2

A K-N2 mixture is irradiated in a glass fluorescence cell with pulses of 710hm radiation from an OPO laser, populated K2 （^1∧g） state by two-photon absorption. The cross section for ^1∧g →^3∧g transfer in K2 is determined using molecular fluorescence spectrometry. The cell temperature is kept constant at 553K. The N2 pressure is varied between 40 Pa and 400 Pa. The effects of K2-K collisions could not be neglected. These effects are subtracted out by using the results of the pure K experiment. The cross sections are （3.8 ± 1.5） ×10^-15 cm^2 for K2 （^1∧g） ＋ N2 → K2（^3∧g） ＋N2 and （8.9 ± 3.5） × 10^-15 cm^2 for K2 （^3∧g） collisions with N2.     

ηb decay into charmonium in association with cc pair

We calculate the inclusive decay rates of ηb into charmonium via double c~ pairs for S- and P-wave states ηc, J/ψ and XcJ within the framework of non-relativistic QCD （NRQCD） factorization at leading order in αs. Besides calculating the contributions of the color-singlet channels ηb → cc[2s＋1SL^（1）]＋cc, the effects of cc pair in the color-octet configurations are also considered. We find that ηb → cc[3S1^（8）] ＋cc make a small contribution to Br（ηb →J/ψ（ηc）＋cc）. While in the ηb →XcJ ＋cc case, the color octet contributions are significant, for they are of the same a 5 order as the color-singlet processes. We predict Br（ηb →J/ψ（ηc）＋cc） = 2.99（2.75） × 10^-5 Vc for S-wave states J/ψ and ηc, and Br（ηb → XcJ ＋cc） = （4.37, 3.40, 2.83） × 10^-5 （for J = 0,1, 2） for P-wave states XcJ. In the end, we also find Br（ηb → cccc） is almost saturated by ηb decay into charmonium in association with cc pair from the point of view of duality.     

Precise correction to parameter ρ in the littlest Higgs model

In this paper tree-level violation of weak isospin parameter, ρ in the frame of the littlest Higgs model is studied. The potentially large deviation from the standard model prediction for the ρ in terms of the littlest Higgs model parameters is calculated. The maximum value for ρ for f=1TeV, c=0.05,c′= 0.05 and υ′= 1.5GeV is ρ=1.2973 which means a large enhancement than the SM.     

Study of new boson W±1 in the Minimal Higgsless Model at the LHC

The Minimal Higgsless Model predicts the existence of new vector gauge boson W1^±, By the process PP →W1^±qq →W^±Z^0qq, Z^0→ 1^＋1^-, W^±→ qq （1=e,μ; q is hadronized to be jets）, we study the sensitivity of searching for this possible vector gauge boson in the level of generator events of signal and backgrounds, then give integrated luminosity required to discover 5σ signal as a function of W1^± mass. The generator for the signal PP → W1^±qq →W^±Z^0qq at tree level is developed with the Minimal Higgsless Model and then interfaced with PYTHIA for the patton showers and hadronization. The backgrounds are produced with MadGraph and PYTHIA.     

Baryon Magnetic Moment and Beta Decay Ratio in Colored Quark Cluster Model

Baryon magnetic moments of p, n, ∑^＋,∑^-,Ξ^0, Ξ^- and the beta decay ratios （G A/Gv ） of n → p, ∑^-→n and Ξ^0→∑^＋ are calculated in a colored quark cluster model. With SU（3） breaking, the model gives a good fit to the experimental values of those baryon magnetic moments and the beta decay ratios. Our results show that the orbital motion has a significant contribution to the spin and magnetic moments of those baryons and the strange component in nucleon is small.     

Studies of Bs^0 → η＇η＇ Decays in pQCD Approach

We calculate the CP averaged branching ratios and CP-violating asymmetries for Bs^0 → η＇η＇ and η＇η＇ decays in the perturbative QCD （pQCD） approach here. The pQCD predictions for the C P-averaged branching ratios are Br（Bs^0 → ηη）=（14.2-7.5^＋18.0） ×10^-6,Br（Bs^0 → ηη＇）=（12.4-7.0^＋18.2）×10^-6,and Br（Bs^0 → η＇η＇） =（9.2-4.9^＋15.3）×10^-6, which agree well with those obtained by employing the QCD factorization approach and also be consistent with available experimental upper limits. The gluonic contributions are small in size： less than 7% for Bs →ηηand ηη＇ decays, and around 18% for Bs →η＇η＇ decay. The CP-violating asymmetries for three decays are very small： less than 3% in magnitude.