130 research outputs found
Beam commissioning of the 35Â MeV section in an intensity modulated proton linear accelerator for proton therapy
This paper presents the experimental results on the Terapia Oncologica con Protoni-Intensity Modulated Proton Linear Accelerator (TOP-IMPLART) beam that is currently accelerated up to 35 MeV, with a final target of 150 MeV. The TOP-IMPLART project, funded by the Innovation Department of Regione Lazio (Italy), is led by Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA) in collaboration with the Italian Institute of Health and the Oncological Hospital Regina Elena-IFO. The accelerator, under construction and test at ENEA-Frascati laboratories, employs a commercial 425 MHz, 7 MeV injector followed by a sequence of 3 GHz accelerating modules consisting of side coupled drift tube linac (SCDTL) structures up to 71 MeV and coupled cavity linac structures for higher energies. The section from 7 to 35 MeV, consisting on four SCDTL modules, is powered by a single 10 MW klystron and has been successfully commissioned. This result demonstrates the feasibility of a “fully linear” proton therapy accelerator operating at a high frequency and paves the way to a new class of machines in the field of cancer treatment
The Top-Implart Proton Linear Accelerator: Interim Characteristics of the 35 Mev Beam
In the framework of the Italian TOP-IMPLART project (Regione Lazio), ENEA-Frascati, ISS and IFO are developing and constructing the first proton linear accelerator based on an actively scanned beam for tumor radiotherapy with final energy of 150 MeV. An important feature of this accelerator is modularity: an exploitable beam can be delivered at any stage of its construction, which allows for immediate characterization and virtually continuous improvement of its performance. Currently, a sequence of 3 GHz accelerating modules combined with a commercial injector operating at 425 MHz delivers protons up to 35 MeV. Several dosimetry systems were used to obtain preliminary characteristics of the 35-MeV beam in terms of stability and homogeneity. Short-term stability and homogeneity better than 3% and 2.6%, respectively, were demonstrated; for stability an improvement with respect to the respective value obtained for the previous 27 MeV beam
Self-amplified spontaneous emission for a single pass free-electron laser
SPARC (acronym of "Sorgente Pulsata ed Amplificata di Radiazione Coerente", i.e. Pulsed and Amplified Source of Coherent Radiation) is a single pass free-electron laser designed to obtain high gain amplification at a radiation wavelength of 500 nm. Self-amplified spontaneous emission has been observed driving the amplifier with the high-brightness beam of the SPARC linac. We report measurements of energy, spectra, and exponential gain. Experimental results are compared with simulations from several numerical codes
High-gain harmonic-generation free-electron laser seeded by harmonics generated in gas
The injection of a seed in a free-electron laser (FEL) amplifier reduces the saturation length and improves the longitudinal coherence. A cascaded FEL, operating in the high-gain harmonic-generation regime, allows us to extend the beneficial effects of the seed to shorter wavelengths. We report on the first operation of a high-gain harmonic-generation free-electron laser, seeded with harmonics generated in gas. The third harmonics of a Ti:sapphire laser, generated in a gas cell, has been amplified and up-converted to its second harmonic (\u3bbrad=133\u2009\u2009nm) in a FEL cascaded configuration based on a variable number of modulators and radiators. We studied the transition between coherent harmonic generation and superradiant regime, optimizing the laser performances with respect to the number of modulators and radiators
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