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Abstract. Numerous domains, in fundamental research as well as in applications, require the study of reactions induced by neutrons with energies from few MeV up to few tens of MeV. Reliable measurements also are necessary to improve the evaluated databases used by nuclear transport codes. This energy range covers a large number of topics like transmutation of nuclear waste, design of future fission and fusion reactors, nuclear medicine or test and development of new detectors. A new facility called Neutrons For Science (NFS) is being built for this purpose on the GANIL site at Caen (France). NFS is composed of a pulsed neutron beam for time-of-flight facility as well as irradiation stations for cross-section measurements. Neutrons will be produced by the interaction of deuteron and proton beams, delivered by the SPIRAL-2 linear accelerator, with thick or thin converters made of beryllium or lithium. Continuous and quasi-mono-energetic spectra will be available at NFS up to 40 MeV. In this fast energy region, the neutron flux is expected to be up to 2 orders of magnitude higher than at other existing time-of-flight facilities. In addition, irradiation stations for neutron-, proton-and deuteron-induced reactions will allow performing cross-section measurements by the activation technique. After a description of the facility and its characteristics, the experiments to be performed in the short and medium term will be presented.

In this work, we measure the hole mobility in the model polymer system poly(3-hexylthiophene-2,5-diyl) by using different measurement techniques. Our main purpose is to determine how the recently developed charge extraction by a linearly increasing voltage technique for metal–insulator–metal devices (MIM-CELIV) compares to other commonly used methods, such as space charge limited currents and time-of-flight. Our findings suggest that the MIM-CELIV technique gives a slightly lower mobility than the other techniques, which is understandable given that the method measures the mobility of relaxed charge carriers in the dark unlike, for example, time-of-flight where charge carriers are photogenerated. In addition, we scrutinize the accuracy and reliability of the techniques used, showing that differences in mobility smaller than a factor of two are not detectable unless statistics from many devices are available.