Muonic oxygen

FIGURE 11.9 Spectrum of the 5 4 transitions in pionic nitrogen and muonic oxygen. 

A. Dupays, B. Lepetit, J.A. Beswick, C. Rizzo, D. Bakalov, Nonzero total-angular-momentum three-body dynamics using hyperspherical elliptic coordinates Application to muon transfer from muonic hydrogen to atomic oxygen and neon, Phys. Rev. A 69 (2004) 062501. 

X-ray spectra from muonic atoms as measured in nitrogen, oxygen, and neon using a Si(Li) detector (Kirch et al. 1999). The spectra are dominated by circular transitions from highly excited states. The spectra show lines of muonic aluminum and carbon from muons stopping in the container wall of the gas target and in scintillators around it... 

---