Introducing the top partner is a common way to cancel the largest quadratically divergent contribution to the Higgs mass induced by the top quark. In this work, we study single top partner production in the tZ channel...Introducing the top partner is a common way to cancel the largest quadratically divergent contribution to the Higgs mass induced by the top quark. In this work, we study single top partner production in the tZ channel at eγ collision in the littlest Higgs model with T-parity(LHT). Since it is well known that polarized beams can enhance the cross section, we analyze the signal via polarized electron beams,and photon beams. we have selected two decay modes for comparison, based on the leptonic or the hadronic decays of the W and Z from the top partner. We then construct a detailed detector simulation, and choose a set of cuts to enhance signal significance. For mode A(B), the capacity for exclusion in this process at s1/2=3TeV is comparable to the current experimental limits with L=1000(500) fb-1. If the integrated luminosity can be increased to 3000 fb-1, the top partner mass+mTcan be excluded up to 1350(1440) GeV at 2σ level. We also considered the initial state radiation effect, and find that this effect reduces the excluding ability of the eγ collision on the the top partner mass by approximately 10 GeV. Moreover, the ability to exclude the LHT parameter space at eγ collision complements the existing research.展开更多
In a simplified model including an SU(2)singlet vector-like top quark T(VLT)with charge 2/3,we investigate the associated production of Wb with VLT at a Compact Linear Collider(CLIC).Focusing on the T→Wb decay channe...In a simplified model including an SU(2)singlet vector-like top quark T(VLT)with charge 2/3,we investigate the associated production of Wb with VLT at a Compact Linear Collider(CLIC).Focusing on the T→Wb decay channel,we discuss two decay models:e+e-→TW+b→(l-vb)(jjb)and e+e-→TW+b→(jjb)(l+νb).In this paper,we consider recent experimental limits including the electroweak precision observables,the width of the top quark,and the direct LHC searches.Through a detailed detector simulation,we show the exclusion and discovery capability on the T at 3 TeV CLIC,where the initial state radiation effect has also been considered.The results show that it is promising to detect the VLT at future high-energy e+e-colliders.展开更多
Based on a simplified model including a singlet vector-like top quark T with charge|Q|=2/3,we analyze the prospects of observing T via the single T production in the tZ channel with Z decaying to neutrinos at the hadr...Based on a simplified model including a singlet vector-like top quark T with charge|Q|=2/3,we analyze the prospects of observing T via the single T production in the tZ channel with Z decaying to neutrinos at the hadronhadron colliders.This simplified model only includes two free parameters,the coupling constant g^(*)and the T quark mass m_(T).To investigate the observability of the single T production,we perform a detailed background analysis and detector simulation for the collision energies 14 TeV,27 TeV,and 100 TeV.We scan the g^(*)-m_(T)parameter space and show the exclusion and discovery capabilities on the T quark with the highest integrated luminosity designed at these colliders.Moreover,the limits from the narrow-width approximation and electro weak precision observables are considered.展开更多
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 （AH）. Considering the current cons...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 （AH）. Considering the current constraints, we investigate the observability of the T-odd top partner pair production through the process pp→T_T_ →ttAHAH 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 2or 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.展开更多
基金supported by the National Natural Science Foundation of China(NNSFC)under grant No.11405047。
文摘Introducing the top partner is a common way to cancel the largest quadratically divergent contribution to the Higgs mass induced by the top quark. In this work, we study single top partner production in the tZ channel at eγ collision in the littlest Higgs model with T-parity(LHT). Since it is well known that polarized beams can enhance the cross section, we analyze the signal via polarized electron beams,and photon beams. we have selected two decay modes for comparison, based on the leptonic or the hadronic decays of the W and Z from the top partner. We then construct a detailed detector simulation, and choose a set of cuts to enhance signal significance. For mode A(B), the capacity for exclusion in this process at s1/2=3TeV is comparable to the current experimental limits with L=1000(500) fb-1. If the integrated luminosity can be increased to 3000 fb-1, the top partner mass+mTcan be excluded up to 1350(1440) GeV at 2σ level. We also considered the initial state radiation effect, and find that this effect reduces the excluding ability of the eγ collision on the the top partner mass by approximately 10 GeV. Moreover, the ability to exclude the LHT parameter space at eγ collision complements the existing research.
基金supported by the National Natural Science Foundation of China(NNSFC)under Grants No.11705048the National Research Project Cultivation Foundation of Henan Normal University under Grant Nos.2020PL16,2021PL10powered by the High Performance Computing Center of Henan Normal University。
文摘In a simplified model including an SU(2)singlet vector-like top quark T(VLT)with charge 2/3,we investigate the associated production of Wb with VLT at a Compact Linear Collider(CLIC).Focusing on the T→Wb decay channel,we discuss two decay models:e+e-→TW+b→(l-vb)(jjb)and e+e-→TW+b→(jjb)(l+νb).In this paper,we consider recent experimental limits including the electroweak precision observables,the width of the top quark,and the direct LHC searches.Through a detailed detector simulation,we show the exclusion and discovery capability on the T at 3 TeV CLIC,where the initial state radiation effect has also been considered.The results show that it is promising to detect the VLT at future high-energy e+e-colliders.
基金Supported by the National Natural Science Foundation of China(NNSFC)(11705048)the National Research Project Cultivation Foundation of Henan Normal University(2020PL16,2021PL10)+1 种基金the Startup Foundation for Doctors of Henan Normal University(qd18115)powered by the High Performance Computing Center of Henan Normal University。
文摘Based on a simplified model including a singlet vector-like top quark T with charge|Q|=2/3,we analyze the prospects of observing T via the single T production in the tZ channel with Z decaying to neutrinos at the hadronhadron colliders.This simplified model only includes two free parameters,the coupling constant g^(*)and the T quark mass m_(T).To investigate the observability of the single T production,we perform a detailed background analysis and detector simulation for the collision energies 14 TeV,27 TeV,and 100 TeV.We scan the g^(*)-m_(T)parameter space and show the exclusion and discovery capabilities on the T quark with the highest integrated luminosity designed at these colliders.Moreover,the limits from the narrow-width approximation and electro weak precision observables are considered.
基金Supported by National Natural Science Foundation of China(NNSFC)(11405047,11305049)the Startup Foundation for Doctors of Henan Normal University(qd15207)
文摘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 （AH）. Considering the current constraints, we investigate the observability of the T-odd top partner pair production through the process pp→T_T_ →ttAHAH 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 2or 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.
