Hadron Production Measurements for Neutrino Physics

One of the limiting factors for the precision of neutrino oscillation experiments is the uncertainty in the composition and spectrum of the neutrino flux. Recently, dedicated hadron production experiments have been taking data and are being planned to supply measurements which can significantly reduce these uncertainties. The HARP experiment has presented results on the measurements of the double‐differential production cross‐section of charged pions in proton interactions with beryllium, carbon, aluminium, copper, tin, tantalum and lead targets. These results are relevant for a detailed understanding of neutrino flux in accelerator neutrino experiments K2K (p–Al data) and MiniBooNE/SciBooNE (p–Be data), for a better prediction of atmospheric neutrino fluxes (p–C, π + – C and π − – C data) as well as for a systematic improvement of hadron production models. The E910 experiment at BNL has recently published their p–Be data. NA49 has measured pion production spectra in p–C interactions and a new experiment, NA61, is starting to take data using essentially the same detector. NA61 plans to measure production spectra for the T2K experiment and for the calculation of extended air showers. MIPP has taken data with a copy of the NuMI target and is progressing in the analysis of these data. An upgrade of the readout of this experiment can greatly increase its potential.