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Lithium fluoride (LiF) is a well-known dosimeter material in pure (McLaughlin et al. Nucl Instrum Methods 175:17–18, 1980) and doped (Lakshmanan et al. Phys Status Solidi (a) 153:265–273, 1996) form. Radiation detectors based on microcrystalline dispersion of LiF in a polymeric matrix have been introduced for gamma and electron high-dose dosimetry (Kovacs et al. Radiat Phys Chem 57:691–695, 2000). In recent years the area of growth and characterisation of LiF thin films has seen a considerable expansion. Polycrystalline LiF films grown by thermal evaporation were proposed and tested as nuclear sensors for neutrons (Cosset et al. Thin Solid Films 303:191–195, 1997) and for gamma dosimetry (Montecchi et al. Point defects in lithium fluoride films induced by gamma irradiation, ch. 116. In: Proceedings of the 7th international conference on advanced technology and particle physics, Como, pp 819–825, 2002). In the last years many efforts have been devoted to the development of novel imaging detectors for extreme-ultraviolet radiation and soft X-rays (Baldacchini et al. J Nanosci Nanotechnol 3:483–486, 2003), hard X-rays (Almaviva et al. Appl Phys Lett 89(5):054102, 2006), as well as low (Baldacchini et al. J Phys Condens Matter 10:857–867, 1998) and high energy electrons. Such solid-state detectors are based on the optical reading of photoluminescence (PL) from stable, visibleemitting colour centres (CCs), produced by irradiation with ionising radiations. These aggregate electronic defects are F2 and FC+ 3 CCs (two electrons bound to two and three close anion vacancies, respectively), which possess almost overlapping absorption bands, peaked at about 450 nm, called M band (Nahum, Phys Rev 157:817–830, 1967). By optical pumping in this spectral region, F2 and FC+ 3 CCs emit broad PL bands peaked at 678 and 541 nm, respectively. LiF films of different thickness were grown by thermal evaporation on different substrates, such as glass and silica, as well as plastic ones (Di Lazzaro et al. Extreme ultraviolet marking system for anti-counterfeiting tags with adjustable security level. In: Allakhverdiev KR (ed) XIX international symposium on high-power laser systems and applications, Istanbul. International Society for Optics and Photonics, p 86770T, 2013). Even in LiF thin films grown on transparent substrates, the direct use of optical absorption spectra to individuate the presence of different kinds of point defects is often precluded by the presence of interference fringes due to the refractive index difference between film and substrate (Nichelatti et al. J Non-Crystalline Solids 322:117–121, 2003). PL measurements are more sensitive and a very effective investigation method, called Combined Excitation-Emission Spectroscopy (Gill et al. Appl Phys Lett 64(19):2483, 1994), can be applied. In this work we present the basic characteristic of this technique and the first results of the investigation of polycrystalline LiF films grown by thermal evaporation on glass substrates and coloured by high-energy electrons in air. © Springer Science+Business Media Dordrecht 2015.

A variable energy (3-7 MeV) and pulsed current (0.1-100 μA) proton beam has been made available for different applications (radiobiology experiments, detectors development, material studies) in an irradiation facility at ENEA-Frascati based on the 7 MeV injector of the proton-therapy linac under realization in the framework of the TOP-IMPLART Project. It is a 425 MHz linear accelerator consisting in a 3 MeV RFQ followed by a DTL up to 7 MeV (PL-7 ACCSYSHITACHI model) followed by an horizontal and a vertical beam transport line. The latter one is particularly suitable for radiobiology in vitro studies allowing to irradiate besides cell monolayers also cell growing in suspension culture. The paper describes the facility and the recent results of the experimental activity. Copyright © 2014 CC-BY-3.0 and by the respective authors.

Point defects in insulating materials are successfully used for radiation detectors. Among them, colour centres in lithium fluoride (LiF) are well known for application in dosimeters and in light-emitting devices and lasers. LiF thin-film detectors for extreme ultraviolet radiation, soft and hard X-rays, based on photoluminescence from aggregate electronic defects, are currently under development for imaging application with laboratory radiation sources, e.g. laser-driven plasma sources and conventional X-ray tubes, as well as large-scale facilities, e.g. synchrotrons and free-electron lasers. Among the peculiarities of these detectors, noteworthy ones are the very high intrinsic spatial resolution (< 100 nm) across a large field of view (> 1 cm 2) and the wide dynamic range. Moreover, they are insensitive to ambient light and no development process is needed. The latent images stored in the LiF thin layer can be read with fluorescence optical microscopy techniques. These detectors prove to be highly versatile, as LiF is sensitive to almost any kind of radiation, including charged particles and neutrons, and can be grown in the form of polycrystalline thin films, whose photoluminescence response can be tailored trough the control of the growth conditions. © Società Italiana di Fisica.

Organic light emitting devices have been so very much improved lately that they are being widely applied for displays and lighting. Among many improving technologies, annealing processes in different atmospheres affect greatly their performance, for instance when the active material is the small molecule Alq3. In particular, a significant increase of the photoluminescence is observed in thin films of this molecule between 150 and 180 °C, before the physical destruction of the films occurs at higher temperatures. This phenomenon is attributed to a phase transition towards a novel morphological aggregation of the molecules in the film, which proved to be a much improved optical material for luminescent applications, and which seems common to other molecules as well.

The influence of Pb2+ doping on the optical properties of LiF crystals before and after irradiation with X-ray was studied by using optical absorption and photoluminescence measurements. After irradiation it was observed an increase of the absorption due to primary and aggregate electronic defects together with a higher photoluminescence signals associated with the F2 and F3+ colour centres in doped samples compared with the undoped ones.

This paper reports on the three new Single Crystal Diamond (SCD) detectors installed at JET for the 2008 Restart campaign. The yields of total neutrons produced during DD plasma pulses as well as the time dependent neutron emission have been measured. The three detectors present some main new developments as for their fabrication characteristics, embeddings and electronic chains. The first detector is 200 ?m thick and is embedded in paraffin. The second detector is 104 ?m thick and is covered by a thermally evaporated 3 ?m thick 6LiF film in order to detect the total and the 14-MeV neutrons. In addition, it is surrounded by a 2.5-cm thick polyethylene shield to enhance its thermal neutron response. The third detector is operated in an innovative way that is with a single low capacitance super-screened cable and its whole electronic chain put outside the JET Torus Hall. Furthermore it uses fast electronics, suitable to the fast diamond response pulse (