Beam test results of 3D pixel detectors constructed with poly-crystalline CVD diamond

As a possible candidate for extremely radiation tolerant tracking devices we present a novel detector design - namely 3D detectors - based on poly-crystalline CVD diamond sensors with a pixel readout. The fabrication of recent 3D detectors as well their results in recent beam tests are presented. We measured the hit efficiency and signal response of two 3D diamond detectors with 50 × 50 μm cell sizes using pixel readout chip technologies currently used at CMS and ATLAS. In all runs, both devices attained efficiencies >98 % in a normal incident test beam of minimum ionising particles. The highest efficiency observed during the beam tests was 99.2 %

An experimental demonstration of a new type of proton computed tomography using a novel silicon tracking detector

Radiography and tomography using proton beams promises benefit to image-guidance and treatment planning for proton therapy. A novel proton tracking detector is described and experimental demon- strations at a therapy facility reported. A new type of proton CT reconstructing relative ‘scattering-power’ rather than ‘stopping-power’ is also demonstrated. Notably, this new type of imaging does not require the measurement of the residual energies of the protons. Successful tracking of protons through a thick target (phantom) has demonstrated that the tracker discussed in this paper can provide the precise directional information needed to perform proton radiography and tomography. When synchronized with a range telescope, this could enable the reconstruction of proton CT images of stopping power. Furthermore, by measuring the deflection of many protons through a phantom it was demonstrated that it is possible to reconstruct a new kind of CT image (scattering power) based upon this tracking information alone

[Paraneoplastic syndromes of the central nervous system]

Paraneoplastic syndromes of central nervous system are rare neurologic syndromes caused by cancer but not secondary to metastases. The physiopathologic mechanisms underlying these syndromes are still under debate. We report the biological and clinical features of the most frequent paraneoplastic syndromes involving the central nervous system. Their early clinical identification might be an useful marker of an otherwise unknown visceral malignancy. Furthermore, they might also be suggestive for the particular type of cancer present. Once, therefore, the diagnosis of these paraneoplastic syndromes has been established, an appropriate evaluation for the asymptomatic neoplasm in cancer-free individuals or investigation for the malignancy recurrences in oncologic patients might be performed

Space charge sign inversion investigation in n-type MCz silicon diodes irradiated by 24 GeV/c and 26 MeV protons and reactor neutrons

Magnetic Czochralski (MCz) silicon is currently being considered as a promising material for the development of radiation tolerant detectors for future high luminosity HEP experiments. Silicon wafers grown by the MCz method have been processed by ITC-IRST (Trento, Italy) with a layout designed by the SMART collaboration. The diodes produced with n-type MCz material have undergone various irradiation campaigns, using 24 GeV/c (SPS-CERN) protons, 26 MeV (FZK-Karlsruhe) protons and reactor neutrons (JSI-Ljubljana), with fluences up to 10(16) 1 MeV equivalent neutrons (n(eq))cm(-2). This paper investigates space charge sign inversion effects after these irradiation levels. Samples have been characterized by reverse current and capacitance measurements before and after irradiation, and by Transient Current Technique (TCT) after irradiation. Results of the Study of depletion voltage as a function of fluence and of TCT signal shapes show that Space Charge Sign Inversion has already occurred in the devices at a fluence of 4.2 x 10(14)n(eq) cm(-2) after 26 MeV proton irradiation, and at 5 x 10(14)n(eq) cm(-2) after neutron irradiation. (C)2007 Elsevier B.V. All rights reserved

Comparison of the radiation hardness of Magnetic Czochralski and Epitaxial silicon substrates after 26 MeV proton and reactor neutron irradiation

We report on the processing and characterization of microstrip sensors and pad detectors produced on n- and p-type Magnetic Czochralski (MCz), Epitaxial (EPI) and Float Zone (FZ) silicon within the SMART project to develop radiation-hard silicon position sensitive detectors for future colliders. Each wafer contains 10 microstrip sensors with different geometries, several diodes and test structures. The isolation in the strip detectors produced on p-type material has been achieved by means of a uniform p-spray implantation, with doping of 3 x 10(12)cm(-2) (low-dose p-spray) and 5 x 10(12)cm(-2) (high-dose p-spray). The samples have undergone irradiations with 26MeV protons and reactor neutrons up to similar to 10(16)cm(-2) 1 MeV equivalent neutrons (n(eq)/cm(2)), and have been completely characterized before and after irradiation in terms of leakage current, depletion voltage and breakdown voltage. The current damage parameter alpha has been determined for all substrates. MCz diodes show less pronounced dependence of effective doping concentration N-eff on the fluence when compared to standard FZ silicon, giving results comparable to diffusion oxygenated FZ devices for all irradiation sources. The observed increase of Neff with fluence can be interpreted in EPI material as a net donor introduction process, overcompensating the usual acceptor introduction process. This effect is stronger for 26MeV proton irradiation than for neutron irradiation. (c) 2007 Elsevier B.V. All rights reserved

Characterization of micro-strip detectors made with high resistivity n- and p-type Czochralski silicon

The results of the pre- and post-irradiation characterization of n- and p-type magnetic Czochralski silicon micro-strip sensors are reported. This work has been carried out within the INFN funded SMART project aimed at the development of radiation-hard semiconductor detectors for the luminosity upgrade of the large Hadron collider (LHC). The detectors have been fabricated at ITC-IRST (Trento, Italy) on 4 in wafers and the layout contains 10 mini-sensors. The devices have been irradiated with 24 GeV/c and 26 MeV protons in two different irradiation campaigns up to an equivalent fluence of 3.4 x 10(15) 1-MeV n/cm(2). The post-irradiation results show an improved radiation hardness of the magnetic Czochralski mini-sensors with respect to the reference float-zone sample. (c) 2006 Elsevier B.V. All rights reserved