寻找希格斯介子，或者说……原力？

大多数物理学家认为，必定有一个希格斯场（Higgs field）贯穿于所有空间，希格斯场由许多被叫做希格斯玻色子（Higgs boson）的粒子组成，它们会与其他粒子互相作用，赋予其他粒子特有的质量。希格斯玻色子也可称为希格斯介子，它是量子物理学标准模型中一个关键的环节，遗憾的是至今没有人发现这种传说中的粒子，所以它目前仍存在于假设中。

Muon g - 2 in the Littlest Higgs Model

在这糊亩的异常磁性的偶极子时刻在上在 littlestHiggs (LH ) ，模型在一个环被学习水平。我们在打破规模 f 的全球对称上讨论贡献的依赖，混合角度 c 和 c' ，和 Higgs 三位字节真空期望在电镀物品珍视 v 弱精确数据比较喜欢范围。我们发现 LH 模型能在异常磁性的时刻把相对小，却非可以忽略的额外的弱贡献给亩并且能为 LH 模型为 SM 从 2.6 σ把Δ a _ μ的偏差归结为 2.5 σ。

Littlest Higgs Model and Higgs Boson Associated Production with Top Quark Pair at High Energy Linear e^＋e^- Collider

在参数，空格由电镀物品允许弱精确测量数据，我们考虑最小的 Higgs 模型预言到 theHiggs 波色子的新粒子的贡献高在未来把生产与最高的夸克对联系了精力线性 e~+e~ 碰撞(ILC ) 。我们发现贡献主要来自新计量器波色子 Z_H 和免费参数的 B_H.For 合理价值，相对修正参数δσ/σ~( SM )的绝对值能 signiScanly 大，它可能与S~( 1/2 )=在未来 ILCexperiment 被观察 800 GeV 。

Probing the Lightest New Gauge Boson BH in the Littlest Higgs Model via Processes γγ→f■B_H at ILC

中立计量器波色子 B 有 GeV 是的百的团的 H 如果它确实存在，最小的 Higgs (LH ) 模型预言的最轻的粒子，和如此的粒子应该是在 planed ILC 的 LH 模型的第一个信号。在这篇论文，我们学习 B 在 ILC 与费米子对联系的 H 生产，即， γγ→ fB H 。研究证明最答应处理检测 B 在 γγ→ 之中的 H fB H 是 γγ→ l'+l'- B H l'= e， μ ) ，并且他们能在电镀物品比较喜欢的大多数参数空格生产足够的信号在 ILC 的弱精确数据。在另一方面，信号经由某些 B H 腐烂模式是典型的，如此的信号能容易从 SM 背景被识别。因此， B H , 在 LH 模型的最轻的计量器波色子，将在在 ILC 认识到的光子 collider 可检测。

Tau Leptonic Decay τ→lVlVτ in Littlest Higgs Model＊

We consider the T leptonic decay τ→lVlVτ in the framework of the littlest Higgs (LH) model and calculate the corrections of new particles to this decay. We find that the contributions of the charged scalars can be safely ignored and the LH model is in perfect agreement with the universality of the couplings of the SU gauge bosons to the leptonic charged currents. The corrections of the LH model to the T leptonic decay τ→lVlVτ are not sensitive to the parameter c, but depend strongly on the parameters f and x. The precision measured data about the T leptonic decay demand that the parameter f approximately equal 3.5 TeV and x > 0.1, while agree with the general expectation based on other phenomenological explorations.

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

Using the form factors from light-cone sum rules,we study the branching ratios and forward-backwardasymmetries (FBAs) of the exclusive decays B_u^+→π^+■^+■^-, ρ^+■^+■-(= e,μ) in the standard model (SM) andthe top quark two-Higgs-doublet model (T2HDM).From the numerical results,we find that the new physics contributionscannot provide very large enhancement to the branching ratios and the theoretical predictions are in good agreementwith the SM ones.The T2HDM effects on FBAs of these decays are small.Precision measurements of the dileptoninvariant mass distributions,especially in the lower dilepton mass region,and the FBAs in the decays B_u^+→π^++(ρ^+)■^+■^-will greatly help in discriminating among the SM and the new physics models.

Top Quark Flavor Changing Decay t→ cH^0 in Little Higgs Model

We study theoretically the quantum effects of the littlest Higgs model (LH) mediated by flavor changing one-loop Feynman diagrams on the rare decay process t → cH0. The comparison of the decay width in the LH model with that in the standard model (SM) is made. We find that the decay branch ratio of t → cH0 in the LH model is at most of the order ～ 10-12, which is two order larger than in the SM. The numerical results show that the difference between the branch ratios in the LH model and the SM is generally sensitive to the LH model parameters, such as symmetry breaking scale f, Higgs boson mass mH0, and x = v'4f /v2 in our chosen parameter space, but relatively insensitive to the value choice of the cosine of the mixing angle c and the ratio λ1/λ2.

Top—Higgs ht^0 and the Process γγ→ZZ

In the context of topcolor-assisted technicolor(TC2) models,we calculate the s-channel contributions of the top-Higgs ht^0 to the process γγ→ZZ.We find that,for reasonable ranges of the paramters,ht^0 can give significant contributions to this process,when the top-Higgs mass approximately equals to the center-of-mass energy s and the free parameter ε=0.01,the cross section can reach 161 fb.which may be detected in the γγ collisions based on the future e+e- colliders.Thus,the process γγ→ZZ may be used to probe the top-Higgs and further test TC2 models in γγ collisions.

Neutral Higgs Boson Pair Production in Standard Model with the Fourth GenerationQuarks at LHC

We investigated the neutral Higgs boson pair production at the CERN Large Hadron Collider (LHC) inthe SM with four families. We found that the gluon-gluon fusion mode is the most dominant one in producing neutralHiggs boson pair at the LHC, and it can be used to probe the trilinear Higgs coupling. If the heavy quarks of the fourthgeneration really exist within the SM, they can manifest their effect on the cross section of the Higgs pair productionprocess at the LHC. Our numerical results show that there will be 2 x 10^4 neutral Higgs boson pair production eventsper year if the next generation heavy quarks really exist, while there will be only 2 x 10^3 events produced per year ifthere are only three families in the SM.

Single Production of gauge boson Z' at TeV Energy e^-γ colliders

In the context of the SU(3) simple group model and the Left-Right twin Higgs(LRTH) model,we study the single production of the new gauge boson Z' via e-γ collision and discuss the possibility to detect this new particle in the TeV energy e+e-collider(LC).The results show that the production cross section of the new heavy gauge boson Z' is in the range of 10.08fb～84.5fb,and the cross section in the LRTH model is bigger than that in the SU(3) simple group model.The sufficient typical events could be assumed in future high energy LC experiments.

揭示物质之谜的一场竞赛

揭示物质之谜的一场竞赛刘家伟，陈敏全世界的物理学家正在为下一个高能物理前沿领域建造加速器。三大洲的高能物理学家正在一项了解为什么宇宙主要由物质组成的竞赛中你追我赶，奋力争先。虽然一度假定物质与反物质数量相等的理论已被修正以适应这一不对称现象，但物理学...