共查询到20条相似文献,搜索用时 15 毫秒
1.
YUE Chong-Xing LI Ding 《理论物理通讯》2008,50(8):441-444
The littlest Higgs model with T-parity, which is called LHT model, predicts the existence of the new particles, such as heavy top quarks, heavy gauge bosons, and mirror fermions. We calculate the one-loop contributions of these new particles to the top quark ehromomagnetic dipole moment (CMDM) AK. We find that the contribution of the LHT model is one order of magnitude smaller than the standard model prediction value. 相似文献
2.
The littlest Higgs model with T-parity, which is called LHT model,
predicts the existence of the new particles, such as heavy top
quarks, heavy gauge bosons, and mirror fermions. We calculate the
one-loop contributions of these new particles to the top quark
chromomagnetic dipole moment (CMDM)
ΔK. We find that the
contribution of the LHT model is one order of magnitude smaller
than the standard model prediction value. 相似文献
3.
In the parameter space allowed by the electroweak precision measurement data, we consider the contributions of the new
particles predicted by the littlest Higgs model to the Higgs boson associated production with top quark pair in the future high energy linear
e+e- collider (ILC). We find that the
contributions mainly come from the new gauge bosons ZH and
BH. For reasonable values of the free parameters, the
absolute value of the relative correction parameter
δσ/σSM can be significanly large, which might
be observed in the future ILC experiment with √{S}=800 GeV. 相似文献
4.
In the littlest Higgs model with T-parity (LHT) the mirror quarks induce the special flavor structures and some new flavor-changing couplings, which could greatly enhance the production rates of the flavor-changing processes. We in this paper study some bottom and anti-strange production processes in the LHT model at the International Linear Collider (ILC), i.e.,e+e- →b\bar{s} andγγ→b\bar{s}. The results show that the production rates of these processes are sizeable for the favorable values of the parameters. Therefore, it is quite possible to test the LHT model or make some constraints on the relevant parameters of the LHT through the detection of these processes at the ILC. 相似文献
5.
6.
The T-parity in the littlest Higgs model can be broken by the anomalous Wess-Zumino-Witten term, which leads that the lightest T-odd gauge boson AH decays into the SM particles. First, we examine some lepton flavor violating decays of AH, namely AH→τ±μ干, AH→τ±e干, and AH→μ±e干. We find that the branching ratios can reach 10-7 for AH→τ±μ干, 10-8 for AH→τ±e干, and 10-8 for AH→μ±e干. Then, we study the lepton flavor violating plus jets signatures of the heavy charged gauge boson and mirror quarks at the LHC, and find that it is possible to be detected for pp→qHqH→τ±μ干+4 jets, and hardly to be detected for pp→qHqH→τ±e干(μ±e干)+4 jets and pp→ WHWH→τ±μ干(τ±e干, μ±e干)+6 jets. 相似文献
7.
8.
LIU Yao-Bei SHEN Jie-Fen CUI Xiao-Min REN Xiao-Yan 《理论物理通讯》2008,49(5):1279-1282
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^±. 相似文献
9.
Within the context of the Littlest Higgs model with T -parity, the heavy photon (AH) is supposed to be an ideal dark matter (DM) candidate. One direct proof of validity of the model is to produce the heavy photon at collider. In this paper, we investigate the associated production of a photon with heavy photon pair at the planned international e+e- linear collider (ILC),i.e., e+e-→ AHAHγ and show the distributions of the transverse momenta of the photon. The numerical results indicate that the heavy photon production rate could reach several fb at the low mass parameter space and the characteristic signal is a single high energetic photon and missing energy, carried by the heavy photons. All in all, it can be a good chance to observe the heavy photon via this process with the high yearly luminosity of the ILC. 相似文献
10.
Within the context of the Littlest Higgs model with T-parity, the heavy photon (AH) is supposed to be an ideal dark matter (DM) candidate. One direct proof of validity of the model is to produce the heavy photon at collider. In this paper, we investigate the associated production of a photon with heavy photon pair at the planned international e+e- linear collider (ILC), i.e. e+e- → AHAHγ and show the distributions of the transverse momenta of the photon. The numerical results indicate that the heavy photon production rate could reach several fb at the low mass parameter space and the characteristic signal is a single high energetic photon and missing energy, carried by the heavy photons. All in all, it can be a good chance to observe the heavy photon via this process with the high yearly luminosity of the ILC. 相似文献
11.
T-odd top partner pair production in the dilepton final states at the LHC in the littlest Higgs Model with T-parity 下载免费PDF全文
In the littlest Higgs model with T-parity, we discuss the pair production of the T-odd top partner(T_) that decays almost 100% into the top quark and the lightest T-odd particle(A_H). Considering the current constraints,we investigate the observability of the T-odd top partner pair production through the process pp→T_T_→tt A_HA_H in the final states with two leptons at 14 TeV LHC. We analyze the signal significance and found that the lower limits on the T-odd top partner mass are approximately 1.2 TeV, 1.3 TeV, and 1.4 TeV at the 2σ confidence level at 14 TeV LHC with an integrated luminosities of 30 fb~(-1), 100 fb~(-1), and 300 fb~(-1), respectively. This lower limit can be increased to approximately 1.5(1.6) TeV if we used 1000(3000) fb~(-1) of the integrated luminosity. 相似文献
12.
In this paper the anomalous magnetic
dipole moment of muon in the
littlest Higgs (LH) model is studied at one-loop level. We discuss the
dependence of the contributions on the global symmetry breaking scale f, mixing angles c and cˊ, and the Higgs triplet vacuum expectation value
vˊ in the electroweak precision data
preferring ranges. We find that the LH model can give a relatively
small, but non-negligible extra weak contribution to the muon
anomalous magnetic moment and can reduce the deviation of
Δaμ from 2.6σ for the SM to 2.5σ for the LH model. 相似文献
13.
We investigated the neutral Higgs boson pair
production at the CERN Large Hadron Collider (LHC) in the SM with
four families. We found that the gluon-gluon fusion mode is the
most dominant one in producing neutral Higgs boson pair at the
LHC, and it can be used to probe the trilinear Higgs coupling. If
the heavy quarks of the fourth generation really exist within the
SM, they can manifest their effect on the cross section of the
Higgs pair production process at the LHC. Our numerical results
show that there will be 2×104 neutral Higgs boson pair
production events per year if the next generation heavy quarks
really exist, while there will be only 2×103 events
produced per year if there are only three families in the SM. 相似文献
14.
QIAO Qing-Peng TANG Jian LI Xue-Qian 《理论物理通讯》2008,50(11):1211-1218
Following previous study, in the littlest Higgs model (LHM), the heavy photon is supposed to be a possiL dark matter candidate and its relic abundance of the heavy photon is estimated in terms of the Boltzman- Lee-Weinba time-evolution equation. The effect of the T-parity violation is also considered. Our calculations show that when Higmass MH taken to be 300 GeV and do not considering T-parity violation, only two narrow ranges 133 〈 MAH 〈 135 Ge and 167 〈 MAH〈 169 GeV are tolerable with the current astrophysical observation and if 135 〈 MAH 〈 167 GeV there must at least exist another species of heavy particle contributing to the cold dark matter. As long as the T-pari; can be violated, the heavy photon can decay into regular standard model particles and would affect the dark matt abundance in the universe, we discuss the constraint on the T-parity violation parameter based on the present dat Direct detection prospects are also discussed in some detail. 相似文献
15.
One of the future goals of the LHC is to precisely measure the properties of the Higgs boson. The associated production of a Higgs boson and top quark pair is a promising process to investigate the related Yukawa interaction and the properties of the Higgs. Compared with the pure scalar sector in the Standard Model, the Higgs sector contains both scalars and pseudoscalars in many new physics models, which makes the ttH interaction more complex and provides a variety of phenomena. To investigate the ttH interaction and the properties of the Higgs, we study the top quark spin correlation observables at the LHC. 相似文献
16.
In the framework of the littlest Higgs model with T-parity(LHT),we study the top quark spin correlation and polarization at the International Linear Collider(ILC).We find that the top quark polarization asymmetry δP t and the left-right asymmetry δA LR can respectively reach-35% and-37.5% for s~(1/2)=500 GeV and s~(1/2)=1000 GeV via e+e-collision,which can reach the observable level at the ILC.By contrast,the spin correlation δC is smaller.The correlation behaviors of these observables at the e+e-collision and the γγ collision will be helpful to distinguish different models and test the LHT model at the ILC. 相似文献
17.
We perform the precision calculations for the e+e-→q_q_(q_q_=u_u_, c_c_, d_d_,s_s_) processes up to the QCD next-to-leading order (NLO) including full weak decays for the final T-odd mirror quarks in the littlest Higgs model with T-parity (LHT) at the Compact Linear Collider (CLIC). We show the dependence of the leading order (LO) and NLO QCD corrected cross sections on the colliding energy √s, and provide the LO and QCD NLO kinematic distributions of final particles. The results show that the LO cross section can be enhanced by the NLO QCD correction and the K-factor increases obviously when the threshold of the on-shell q_q_-pair production approaches the colliding energy √s. The K-factor value varies in the range of 1.04 ~ 1.41 in our chosen parameter space. We find that a simple approximation of multiplying the LO kinematic distribution with the integrated K-factor is not appropriate for precision study of the e+e-→q_q_(q_q_=u_u_, c_c_, d_d_,s_s_) processes, since the NLO QCD corrections are phase space dependent. It is necessary to calculate the differential cross sections including full NLO QCD corrections to get reliable results. 相似文献
18.
In the framework of the littlest Higgs model with T-parity,we study the top pair production at the next generation colliders like LHC and ILC.We find that the order O(αs) corrections to the standard model top pair production cross section at LHC can be very small and the magnitude is below 1%.However,the magnitude of corrections to the standard model top pair production rate at ILC may be over 5% for reasonable values'of the parameters.Besides this,the corrections to the asymmetry ALR(tt) may be more sizable. Therefore,the top pair production at ILC may serve as a probe of the littlest Higgs model with T-parity,especially the asymmetry ALR(tt). 相似文献
19.
In this paper we investigate the effects of the large extra dimensions on the two processes
e+e-→
H0Z0Z0 and e+e-→ H0Z0Z0 at linear colliders in both unpolarized and polarized collision modes. We
find that the virtual Kaluza-Klein graviton exchange can significantly enhance the cross section from their standard model expectations for these two processes. The results show that the
LED effect on the process
e+e-→
H0Z0Z0
allows the observation limits on
the effective scale MS to be probed up to 9.75 TeV and 10.1 TeV
in the unpolarized and
+-(λe+=1/2,
λe-=-1/2) polarized beam collision modes (with
Pe+=0.6,
Pe-=0.8), respectively. For the process
e+e-→
H0Z0Z0, these limits on MS can be
probed up to 6.06 TeV and 6.38 TeV in the unpolarized and polarized
collision modes separately. We find that the λe+=1/2,
λe-=-1/2 polarization collision mode in both
process e+e-→ H0Z0Z0 and e+e-→ H0Z0Z0
may provide a possibility to improve the
sensitivity in probing the LED effects. 相似文献
20.
In the framework of the littlest Higgs model with T-parity, we study the top pair production at the next generation colliders like LHC and ILC. We find that the order O(αs) corrections to the standard model top pair production cross section at LHC can be very small and the magnitude is below 1%. However, the magnitude of corrections to the standard model top pair production rate at ILC may be over 5% for reasonable values'of the parameters. Besides this, the corrections to the asymmetry ALR(tt) may be more sizable. Therefore, the top pair production at ILC may serve as a probe of the littlest Higgs model with T-parity, especially the asymmetry ALR(tt). 相似文献