Antimuoni

Antimuoni, or antimuons, are the antiparticles of muons, elementary leptons in the second generation of the Standard Model. They have the same mass as muons, about 105.7 MeV/c^2, and a spin of 1/2, but carry a positive electric charge (+e). Like muons, antimuons are unstable and decay via the weak interaction with a mean lifetime of about 2.2 microseconds. The decay channels mirror those of muons: a positive muon decays as mu+ → e+ + νe + anti-νμ, while a negative muon would decay as mu− → e− + anti-νe + νμ.

Antimuons are produced in high-energy processes such as cosmic ray interactions and particle accelerators. In charged pion decays, π− → μ− + anti-νμ yields muons, while the charge-conjugate process π+ → μ+ + νμ yields antimuons. They are also produced in high-energy collisions that generate antiparticles and in various decay chains of heavier hadrons. Because they carry opposite lepton charge to muons, antimuons participate in the same fundamental interactions (electromagnetic and weak) and obey the same kinematics, but contribute opposite lepton-number signs in analyses.

In detectors, antimuons behave similarly to muons: they traverse matter with minimal energy loss by ionization, radiate via bremsstrahlung at high energies, and can be identified through tracking systems, scintillators, Cherenkov detectors, and dedicated muon chambers. Studying antimuons helps test CPT symmetry, lepton universality, and neutrino-related phenomena, and provides essential calibration tools for accelerator and cosmic-ray experiments.