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The use of protons and heavy ions for the treatment of tumors is increasing since it provides a better relative biological effectiveness (RBE) than traditional radiotherapy. Accurate knowledge of the energy deposition at submicrometric scales is paramount for RBE characterization. This paper shows the latest version of the silicon cylindrical microdosimeter array developed by the Instituto de Microelectrónica de Barcelona, Centro Nacional de Microelectrónica (IMB-CNM, Spain). The detector consists of a matrix of $11 \times 11$ cylindrical sensitive unit cells with individual readout etched within the silicon substrate available in different diameters and pitches between detectors. The detector employed in this paper had a diameter of $15~\mu \text{m}$ , a pitch of $200~\mu \text{m}$ , and a thickness of $5.5~\mu \text{m}$. The detectors were tested in the clinical facilities of Fondazione Centro Nazionale di Adronterapia Oncologica (CNAO) (Pavia, Italy) employing a 12C pencil beam at a therapeutic beam fluence rate. Microdosimetric spectra of lineal energy were measured in different depths of polymethyl methacrylate (PMMA) up to the Bragg peak. Results were then compared with Monte Carlo simulations using the FLUKA particle transport code, showing an excellent agreement between experimental and simulated microdosimetric distributions even at the high fluence rates associated with clinical beams. [ABSTRACT FROM AUTHOR]

The article presents information on the 2004 Workshop on Radiation and its Effects on Components and Systems (RADECS), which was held from September 22-24, 2005 in Madrid, Spain. The special issue of the journal "IEEE Transactions on Nuclear Science" contains selected papers from the Workshop. At least three reviewers scrutinized these manuscripts to ensure that all manuscripts were original and represented significant contributions to the literature. A separate proceedings of this RADECS 2004 Workshop contains a complete record of all manuscripts presented orally or via poster.

The papers in this special issue were presented at the 2011 RADECS (Radiation Effects on Component and Systems) Conference that was held September 19-23, 2011, in Sevilla, Spain. [ABSTRACT FROM AUTHOR]

The article presents an overview of the 8th European Workshop on Radiation and its Effects on Components and Systems, which was held from September 19-23, 2004, at the CIEMAT facilities in Madrid, Spain. More than 210 participants from 26 countries all over the world attended this workshop. A total of 58 papers were presented in this workshop. The attendees also had the possibility to use the breaks to visit the industrial exhibition, composed of nine booths with a good representation of the different sectors, which involved component manufacturers, service providers, etc.

In this work, we compare two commercial positron emission tomography (PET) scanners installed at CIEMAT (Madrid, Spain): the ClearPET and the rPET-1. These systems have significant geometrical differences, such as the axial field of view (110 mm on ClearPET versus 45.6 mm on rPET-1), the configuration of the detectors (whole ring on ClearPET versus one pair of planar blocks on rPET-1) and the use of an axial shift between ClearPET detector modules. We used an assessment procedure that fulfilled the recommendations of the National Electrical Manufacturers Association (NEMA) NU 4-2008 standard. The methodology includes studies of spatial resolution, sensitivity, scatter fraction, count losses and image quality. Our experiments showed a central spatial resolution of 1.5 mm (transaxial), 3.2 mm (axial) for the ClearPET and 1.5 mm (transaxial), 1.6 mm (axial) for the rPET-1, with a small variation across the transverse axis on both scanners (\sim1 mm). The absolute sensitivity at the centre of the field of view was 4.7% for the ClearPET and 1.0% for the rPET-1. The peak noise equivalent counting rate for the mouse-sized phantom was 73.4 kcps reached at 0.51 MBq/mL on the ClearPET and 29.2 kcps at 1.35 MBq/mL on the rPET-1. The recovery coefficients measured using the image quality phantom ranged from 0.11 to 0.89 on the ClearPET and from 0.14 to 0.81 on the rPET-1. The overall performance shows that both the ClearPET and the rPET-1 systems are very suitable for preclinical research and imaging of small animals. [ABSTRACT FROM AUTHOR]