Background: During intensity modulated radiation therapy (IMRT) technique, theoretically, presence of flattening filter (FF) across the beamline of clinical linear accelerator (linac) is not essential to obtain uniform lateral profiles due to intensity modulation of photon beams by multileaf collimators (MLCs). The aim of this study was to investigate the dosimetrical properties of 18 MV photon...

Introduction: In clinical electron beams, most of bremsstrahlung radiation is produced by various linac head structures. This bremsstrahlung radiation dose is influenced by the geometry and construction of every component of the linac treatment head structures. Thus, it can be expected that the amount of the contaminated photon dose due to bremsstrahlung radiation varies among different linacs,...

This planning study was performed to compare stereotactic linac based radiosurgery of Arteriovenous Malformations (AVM) with current Helical Tomotherapy (HT) and future HT techniques. For 10 patients with AVM, dose distributions and treatment times of "regular" HT delivery (Reg 2.5/1/0.6 cm field width), Running-Start-Stop Treatment (RSS 5/2.5 cm), Axial Mode (Axial 5 cm) and Dynamic Jaw/Dynami...

After extraction, the damping ring (DR) bunch length is eom@essed in the RTL (Ring-To-Linac) transport line to achieve the desired linac bunch length. For this, an energy spread is induced proportional to the DR bunch length, producing large, aperture filling, horizontal beam sizes in the dispersive regions of the RTL. There, nonlinear magnetic fields and wakefields cause higher order dispersio...

PURPOSE This study investigates the feasibility and potential benefits of radiotherapy with a 1.5T MR-Linac for locally advanced non-small cell lung cancer (LA NSCLC) patients. MATERIAL AND METHODS Ten patients with LA NSCLC were retrospectively re-planned six times: three treatment plans were created according to a protocol for conventionally fractionated radiotherapy and three treatment pla...

Dalian Coherent Light Source (DCLS) will use a 300MeV LINAC to produce fully coherent photon pulses in the wavelength range between 150-50nm by high gain harmonic generation free electron laser (FEL) scheme [1]. Beam quality requirements for the linear accelerator (linac) are critical, including not only the beam brightness, but also the stability and the reliability. In this paper, optimizatio...

Linac4 is a normal conducting H_ linac proposed at CERN to provide a higher proton flux to the CERN accelerator chain. It should replace the existing Linac2 as injector for the PS booster (PSB). The same machine can also operate in the future as the front end of the SPL, a 2.2GeV superconducting linac with 1.8 mA average current. At present Linac4 consists of a Radio Frequency Quadrupole (RFQ),...

The Radioactive Beam Experiment (REX-ISOLDE) [1,2] is a pilot experiment at ISOLDE (CERN) testing the new concept of post acceleration of radioactive ion beams by using charge breeding of the ions in a high charge state ion source and the efficient acceleration of the highly charged ions in a short LINAC using modern ion accelerator structures. In order to prepare the ions for the experiments s...

In light of the SPEAR3 upgrade project where the goal is to store up to 500 mA of beam current at 3.0 GeV beam energy, the injector RF gun and linac performance must be optimised in terms of reliability and injection rate. The basic linac system layout has not been changed for the last ten years of operation. A thermionic1.5-cell standing wave RF gun is the source of bunched beams at 10 Hz. An ...

The measurement of the transverse beam emittance is essential in any particle accelerator. This paper describes the problems of transverse emittance measurement for the new H LINAC being built at CERN as a replacement of the existing proton LINAC.