Constraining Muon Internal Bremsstrahlung as a Contribution to the MiniBooNE Low Energy Excess

Abstract

Using a cleanly tagged data sample of $\hat{I}{½}_{\hat{I}}¼$ charged current events, it is demonstrated that the rate at which such events are mis-identified as $\hat{I}{½}_e$'s is accurately simulated in the MiniBooNE $\hat{I}{½}_{\hat{I}}¼\to \hat{I}{½}_e$ analysis. Such mis-identification, which could arise from muon internal bremsstrahlung, is decisively ruled out as a source of the low energy electron-like events reported in the MiniBooNE search for $\hat{I}{½}_{\hat{I}}¼\to \hat{I}{½}_e$ oscillations. This refutes the conclusions of a recent paper which postulates that hard bremsstrahlung could form a substantial background to the MiniBooNE $\hat{I}{½}_e$ sample.

3 pages, 3 figures. Response to arXiv:0709.4004 [hep-ex]. Submitted to Phys. Rev. D (Brief Reports)