The decay of the Higgs boson and the nature of dark matter remain fundamental challenges in particle physics.We investigate the 95 GeV diphoton excess and dark matter within the framework of the triplet-extended minim...The decay of the Higgs boson and the nature of dark matter remain fundamental challenges in particle physics.We investigate the 95 GeV diphoton excess and dark matter within the framework of the triplet-extended minimal supersymmetric standard model(TMSSM).In this model,an additional hypercharge Y=0,SU(2)_(L) triplet superfield is introduced.Mixing between the triplet and doublet Higgs states enhances the diphoton signal strength of the 95 GeV Higgs boson,resulting in μ_(γγ)^(CMMS+ATLAS)=0.224_(0.08)^(+0.09),wcicnistnitxmltions.This enhancement arises primarily from charged Higgs and chargino loop contributions,together with an LEP excess in the Zbb channel around the same mass within the 2σ range.Additionally,the model accommodates viable dark matter candidates in the form of a bino-dominated neutralino.The relic density is reduced to the observed value through resonance-enhanced annihilation via the Higgs portal or co-annihilation with the triplino or higgsino.This reduction remains consistent with constraints from direct and indirect detection experiments.A comprehensive parameter scan demonstrates that the TMSSM can simultaneously explain the 95 GeV diphoton excess,observed 125 GeV Higgs mass,and dark matter relic density,establishing a compelling and theoretically consistent framework.展开更多
Recently, both ATLAS and CMS collaborations at the CERN Large Hadron Collider （LHC） announced their observations of an excess of diphoton events around the invariant mass of 750 GeV with a local significance of 3.6a...Recently, both ATLAS and CMS collaborations at the CERN Large Hadron Collider （LHC） announced their observations of an excess of diphoton events around the invariant mass of 750 GeV with a local significance of 3.6a and 2.6a, respectively. In this paper, we interpret the diphoton excess as the on-shell production of a real singlet scalar in the pp → S →γγchannel. To accommodate the observed production rate, we further introduce a vector-like fermion F, which carries both color and electric charges. The viable regions of model parameters are explored for this simple extension of the Standard Model （SM）. Moreover, we revisit the problem of electroweak vacuum stability in the same scenario, and find that the requirement for the electroweak vacuum stability up to high energy scales imposes serious constraints on the Yukawa coupling of the vector-like fermion and the quartic couplings of the SM Higgs boson and the new singlet scalar. Consequently, a successful explanation for the diphoton excess and the absolute stability of electroweak vacuum cannot be achieved simultaneously in this economical setup.展开更多
Motivated by experimental hints and theoretical frameworks indicating the existence of an extended Higgs sector,we explore the feasibility of detecting a 95 GeV light Higgs boson decaying into a diphoton within the mi...Motivated by experimental hints and theoretical frameworks indicating the existence of an extended Higgs sector,we explore the feasibility of detecting a 95 GeV light Higgs boson decaying into a diphoton within the minimal dilaton model at the 14 TeV LHC.Initially,we identify the correlations between the production cross section,decay branching ratios,and model parameters,e.g.,the scalar mixing angle■Subsequently,we utilize Monte Carlo simulations to generate the signal of the light Higgs boson via the■process,along with the corresponding backgrounds.To effectively separate the signal from the dominant backgrounds■,we employ a meticulous cut-based selection process.Ultimately,we find that with an integrated luminosity of L=3000fb^(-1),the regions of■can be covered over the3σlevel.展开更多
By analyzing the large-angle Bhabha scattering events e^＋e^- → （γ）e^＋e^- and diphoton events e^＋^e- → （γ）γγ for the data sets collected at center-of-mass （c.m.） energies between 2.2324 and 4.5900 GeV （...By analyzing the large-angle Bhabha scattering events e^＋e^- → （γ）e^＋e^- and diphoton events e^＋^e- → （γ）γγ for the data sets collected at center-of-mass （c.m.） energies between 2.2324 and 4.5900 GeV （131 energy points in total） with the upgraded Beijing Spectrometer （BESIII） at the Beijing Electron-Positron Collider （BEPCII）, the integrated luminosities have been measured at the different c.m. energies, individually. The results are important inputs for the R value and J/ψ resonance parameter measurements.展开更多
The diphoton invariant mass distribution from the interference between gg→H→γγ and gg→γγ is almost antisymmetric around the Higgs mass MH.We propose a new observable Aint,the ratio of the sign-reversed integral...The diphoton invariant mass distribution from the interference between gg→H→γγ and gg→γγ is almost antisymmetric around the Higgs mass MH.We propose a new observable Aint,the ratio of the sign-reversed integral around MH(e.g.■)and the cross-section of the Higgs signal,to quantify this effect.We study Aint both in the Standard Model(SM)and new physics with various CP violating Hγγ couplings.Aint in SM could reach a value of 10%,while for CP violating Hyy coupling Aint could range from 10% to-10%,which could probably be detected in the HL-LHC experiments.Aint with both CP violating Hγγ and Hgg couplings is also studied,and its range of values is found to be slightly larger.展开更多
The new particle around 125 GeV observed at the LHC is almost consistent with the standard model Higgs boson, except that the diphoton decay mode may be excessive. We summarize a number of possibilities. We propose to...The new particle around 125 GeV observed at the LHC is almost consistent with the standard model Higgs boson, except that the diphoton decay mode may be excessive. We summarize a number of possibilities. We propose to use the vector-boson fusion to test the underlying model for electroweak symmetry breaking. Using the well known dijet-tagging technique to single out the vector-boson fusion mechanism, we investigate potential of vector-boson fusion to discriminate a number of models suggested to give an enhanced inclusive diphoton production rate.展开更多
基金Supported by the National Natural Science Foundation of China(NNSFC)(12275232,12335005)Bin Zhu is also supported by the Natural Science Foundation of Shandong Province(ZR2025QA20)。
文摘The decay of the Higgs boson and the nature of dark matter remain fundamental challenges in particle physics.We investigate the 95 GeV diphoton excess and dark matter within the framework of the triplet-extended minimal supersymmetric standard model(TMSSM).In this model,an additional hypercharge Y=0,SU(2)_(L) triplet superfield is introduced.Mixing between the triplet and doublet Higgs states enhances the diphoton signal strength of the 95 GeV Higgs boson,resulting in μ_(γγ)^(CMMS+ATLAS)=0.224_(0.08)^(+0.09),wcicnistnitxmltions.This enhancement arises primarily from charged Higgs and chargino loop contributions,together with an LEP excess in the Zbb channel around the same mass within the 2σ range.Additionally,the model accommodates viable dark matter candidates in the form of a bino-dominated neutralino.The relic density is reduced to the observed value through resonance-enhanced annihilation via the Higgs portal or co-annihilation with the triplino or higgsino.This reduction remains consistent with constraints from direct and indirect detection experiments.A comprehensive parameter scan demonstrates that the TMSSM can simultaneously explain the 95 GeV diphoton excess,observed 125 GeV Higgs mass,and dark matter relic density,establishing a compelling and theoretically consistent framework.
基金Supported by Innovation Program of the Institute of High Energy Physics(Y4515570U1)National Youth Thousand Talents ProgramCAS Center for Excellence in Particle Physics(CCEPP)
文摘Recently, both ATLAS and CMS collaborations at the CERN Large Hadron Collider （LHC） announced their observations of an excess of diphoton events around the invariant mass of 750 GeV with a local significance of 3.6a and 2.6a, respectively. In this paper, we interpret the diphoton excess as the on-shell production of a real singlet scalar in the pp → S →γγchannel. To accommodate the observed production rate, we further introduce a vector-like fermion F, which carries both color and electric charges. The viable regions of model parameters are explored for this simple extension of the Standard Model （SM）. Moreover, we revisit the problem of electroweak vacuum stability in the same scenario, and find that the requirement for the electroweak vacuum stability up to high energy scales imposes serious constraints on the Yukawa coupling of the vector-like fermion and the quartic couplings of the SM Higgs boson and the new singlet scalar. Consequently, a successful explanation for the diphoton excess and the absolute stability of electroweak vacuum cannot be achieved simultaneously in this economical setup.
基金Supported by the National Natural Science Foundation of China(12275066,11605123)。
文摘Motivated by experimental hints and theoretical frameworks indicating the existence of an extended Higgs sector,we explore the feasibility of detecting a 95 GeV light Higgs boson decaying into a diphoton within the minimal dilaton model at the 14 TeV LHC.Initially,we identify the correlations between the production cross section,decay branching ratios,and model parameters,e.g.,the scalar mixing angle■Subsequently,we utilize Monte Carlo simulations to generate the signal of the light Higgs boson via the■process,along with the corresponding backgrounds.To effectively separate the signal from the dominant backgrounds■,we employ a meticulous cut-based selection process.Ultimately,we find that with an integrated luminosity of L=3000fb^(-1),the regions of■can be covered over the3σlevel.
基金Supported by National Key Basic Research Program of China(2015CB856700)National Natural Science Foundation of China(NSFC)(10935007,11121092,11125525,11235011,11322544,11335008,11375170,11275189,11079030,11475164,11475169,11005109,10979095,11275211)+8 种基金Chinese Academy of Sciences(CAS)Large-Scale Scientific Facility ProgramJoint Large-Scale Scientific Facility Funds of the NSFC and CAS(11179007,U1232201,U1332201,U1532102).(KJCX2-YW-N29,KJCX2-YW-N45)100 Talents Program of CAS,INPAC and Shanghai Key Laboratory for Particle Physics and Cosmology,German Research Foundation DFG(Collaborative Research Center CRC-1044)Istituto Nazionale di Fisica Nucleare,Italy,Ministry of Development of Turkey(DPT2006K-120470)Russian Foundation for Basic Research(14-07-91152)U.S.Department of Energy(DE-FG02-04ER41291,DE-FG02-05ER41374,DEFG02-94ER40823,DESC0010118)U.S.National Science Foundation,University of Groningen(RuG)the Helmholtzzentrum fuer Schwerionenforschung Gmb H(GSI)Darmstadt,WCU Program of National Research Foundation of Korea(R32-2008-000-10155-0)
文摘By analyzing the large-angle Bhabha scattering events e^＋e^- → （γ）e^＋e^- and diphoton events e^＋^e- → （γ）γγ for the data sets collected at center-of-mass （c.m.） energies between 2.2324 and 4.5900 GeV （131 energy points in total） with the upgraded Beijing Spectrometer （BESIII） at the Beijing Electron-Positron Collider （BEPCII）, the integrated luminosities have been measured at the different c.m. energies, individually. The results are important inputs for the R value and J/ψ resonance parameter measurements.
基金Supported by the National Natural Science Foundation of China(11405102,11847168)the Fundamental Research Funds for the Central Universities of China(GK201603027,GK201803019,1301030621)the Natural Science Foundation of Shannxi Province,China(2019JM-431)
文摘The diphoton invariant mass distribution from the interference between gg→H→γγ and gg→γγ is almost antisymmetric around the Higgs mass MH.We propose a new observable Aint,the ratio of the sign-reversed integral around MH(e.g.■)and the cross-section of the Higgs signal,to quantify this effect.We study Aint both in the Standard Model(SM)and new physics with various CP violating Hγγ couplings.Aint in SM could reach a value of 10%,while for CP violating Hyy coupling Aint could range from 10% to-10%,which could probably be detected in the HL-LHC experiments.Aint with both CP violating Hγγ and Hgg couplings is also studied,and its range of values is found to be slightly larger.
文摘The new particle around 125 GeV observed at the LHC is almost consistent with the standard model Higgs boson, except that the diphoton decay mode may be excessive. We summarize a number of possibilities. We propose to use the vector-boson fusion to test the underlying model for electroweak symmetry breaking. Using the well known dijet-tagging technique to single out the vector-boson fusion mechanism, we investigate potential of vector-boson fusion to discriminate a number of models suggested to give an enhanced inclusive diphoton production rate.
