Double di ffential fragmentation cross sections measurements of 95 MeV/u 12C on thin targets for hadrontherapy

During therapeutic treatment with heavy ions like carbon, the beam undergoes nuclear fragmentation and secondary light charged particles, in particular protons and alpha particles, are produced. To estimate the dose deposited into the tumors and the surrounding healthy tissues, an accurate prediction on the fluences of these secondary fragments is necessary. Nowadays, a very limited set of double di ffential carbon fragmentation cross sections are being measured in the energy range used in hadrontherapy (40 to 400 MeV/u). Therefore, new measurements are performed to determine the double di ffential cross section of carbon on di erent thin targets. This work describes the experimental results of an experiment performed on May 2011 at GANIL. The double di ffential cross sections and the angular distributions of secondary fragments produced in the 12C fragmentation at 95 MeV/u on thin targets (C, CH2, Al, Al2O3, Ti and PMMA) have been measured. The experimental setup will be precisely described, the systematic error study will be explained and all the experimental data will be presented.Comment: Submitted to PR

Interaction vertex imaging (IVI) for carbon ion therapy monitoring: a feasibility study

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Real time monitoring of the Bragg-peak position in ion therapy by means of single photon detection

For real-time monitoring of the longitudinal position of the Bragg-peak during an ion therapy treatment, a novel non-invasive technique has been recently proposed that exploits the detection of prompt -rays issued from nuclear fragmentation. Two series of experiments have been performed at the GANIL and GSI facilities with 95 MeV/u and 305 MeV/u 12C6+ ion beams stopped in PMMA and water phantoms. In both experiments a clear correlation was obtained between the carbon ion range and the prompt photon profile. Additionally, an extensive study has been performed to investigate whether a prompt neutron component may be correlated with the carbon ion range. No such correlation was found. The present paper demonstrates that a collimated set-up can be used to detect single photons by means of time-of-flight measurements, at those high energies typical for ion therapy. Moreover, the applicability of the technique both at cyclotron and synchrotron facilities is shown. It is concluded that the detected photon count rates provide sufficiently high statistics to allow real-time control of the longitudinal position of the Bragg-peak under clinical conditions

Comparison of two analysis methods for nuclear reaction measurements of 12C +12C interactions at 95 MeV/u for hadrontherapy

During therapeutic treatment with heavier ions like carbon, the beam undergoes nuclear fragmentation and secondary light charged particles, in particular protons and alpha particles, are produced. To estimate the dose deposited into the tumors and the surrounding healthy tissues, the accuracy must be higher than ($\pm$3% and$\pm$1 mm). Therefore, measurements are performed to determine the double differential cross section for different reactions. In this paper, the analysis of data from 12C +12C reactions at 95 MeV/u are presented. The emitted particles are detected with \DeltaEthin-\DeltaEthick-E telescopes made of a stack of two silicon detectors and a CsI crystal. Two different methods are used to identify the particles. One is based on graphical cuts onto the \DeltaE-E maps, the second is based on the so-called KaliVeda method using a functional description of \DeltaE versus E. The results of the two methods will be presented in this paper as well as the comparison between both

Nouvelles méthodes d'imagerie en ligne pour le contrôle de l'irradiation en hadronthérapie

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Sample environment and experimental set-up for inelastic x-ray scattering measurements of liquid hydrogen fluoride and HFx H2O1-x solutions.

In order to study the dynamic structure factor of hydrogen fluoride and its water solutions, we have realized a sample container able to resist these highly reacting hydrogen-bonded liquids and suitable for near-forward x-ray scattering experiments. The design and development of each part of the apparatus together with a discussion on the choice of the materials is reported. Two cells have been built for pure HF and for (HF)x(H2O)1–x solutions based on similar schemes but developed with different materials and some structural variations. Their contribution to the total scattered intensity has been measured. An example of inelastic x-ray scattering spectra at fixed temperature (T = 283 K) and momentum transfer (Q = 4 nm–1) is reported as a function of the concentration of hydrogen fluoride [(HF)x(H2O)1–x,with x = 0,0.2,0.4,0.73,1]

Bulk electronic properties of V2O3 probed by hard X-ray photoelectron spectroscopy

We have measured bulk sensitive photoemission spectra of pure vanadium sesquioxide (V2O3) in its metallic phase as a function of different surface preparations. We observe the presence of a clear coherent peak in the vicinity of the Fermi level and of satellites intensities at the V 2p core level. After scraping, the coherent intensities are almost completely suppressed in both core level and valence band. Our results suggest a remarkable change of the screening properties in strongly correlated systems when going from the surface to the volume

Genetic diversity in connected reintroduced population: long term data on Griffon vulture (Gyps fulvus) in Europe.

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