【摘 要】
:
The standard model (SM) of particle physics,comprised of the unified electroweak and quantum chromodynamic theories,accurately explains almost all experimental results related to the micro-word,and has made a number of predictions for previously unseen pa
【机 构】
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School of Physics,Nanjing University,Nanjing 210093,China;Nanjing Proton Source Research and Design
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The standard model (SM) of particle physics,comprised of the unified electroweak and quantum chromodynamic theories,accurately explains almost all experimental results related to the micro-word,and has made a number of predictions for previously unseen particles,most notably the Higgs scalar boson,that were subsequently discovered.As a result,the SM is currently universally accepted as the theory of the fundamental particles and their interactions.However,in spite of its numerous successes,the SM has a number of apparent shortcomings,including:many free parameters that must be supplied by experimental measurements;no mechanism to produce the dominance of matter over antimatter in the universe;and no explanations for gravity,the dark matter in the universe,neutrino masses,the number of particle generations,etc.Because of these shortcomings,there is considerable incentive to search for evidence for new,non-SM physics phenomena that might provide important clues about what a new,beyond the SM theory (BSM) might look like.Although the center-of-mass energies that BESⅢ can access are far below the energy frontier,searches for new,BSM physics are an important component of its research program.Tnis report reviews some of the highlights from BESⅢ\'s searches for signs of new,B SM physics by:measuring rates for processes that the SM predicts to be forbidden or very rare;searching for non-SM particles such as dark photons;performing precision tests of SM predictions;and looking for violations of the discrete symmetries C and CP in processes for which the SM expectations are immeasurably small.
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