Uniform beam distributions at the target of the NASA Space Radiation Laboratory’s beam line

Abstract

Errors in delivering a uniformly distributed radiation dose to biological and material samples exposed to charged particle beams are a significant problem for experimenters. In this paper, we discuss data collected on the uniform beam distributions produced for NASA's Space Radiation Laboratory (NSRL) at Brookhaven National Laboratory (BNL), using a method that was conceived theoretically and tested experimentally at BNL. This method [N. Tsoupas et al., Nucl. Sci. Eng. 126, 71 (1997)] of generating uniform beam distributions on a plane normal to the beam's direction relies only on magnetically focusing the transported beam; no collimation of the beam is required or any other type of interaction of the beam with materials other than the target material. The method compares favorably with alternative methods of producing such distributions, and it can be applied to the entire energy spectrum of charged particle beams that are delivered to the NSRL's experiments by the Booster for the Alternating Gradient Synchrotron at BNL.

The recent progress and future of oxygen reduction reaction catalysis: A review

“…A schematic representation of the transport line from the ion source to NSRL exposure room is shown in Figure 1 together with a map of the facility. Figure 1: Layout of the accelerators and user facility for NSRL: sources (EBIS, Tandem and LINAC), synchrotron (Booster), transport segment between the Booster and the exposure room (R-Line) (Tsoupas et al, 2007) and NSRL building.…”

“…The particle beams produced by any of the sources mentioned above are injected into the Booster synchrotron where they are further accelerated to reach the final energy and delivered to NSRL via a single line branching off from the Booster (R-Line). A detailed description of all R-line elements is reported in (Tsoupas et al, 2007). The beam time structure can be varied over a large range from 300 ms to over 2 s, with particles bunches (referred to as spills) delivered every 4-6 s, depending on the other Booster activities.…”

Uniformization of the transverse beam profile by means of nonlinear focusing method

“…His work was extended by Meot et al, who derived the strength up to the dodecapole component considering a realistic beam optics [8]. Recently, uniform beam formation using two octupole magnets was experimentally demonstrated [9,10]. This method can be also used for halo reduction of nanobeams colliding in the final focusing system [11].…”

Feasibility study for a biomedical experimental facility based on LEIR at CERN

“…In the long term, a beam scanning system, as in modern ion beam treatment centres, would provide maximum flexibility, allowing the simulation of complex beam deliveries for medical physics experiments while at the same time providing the possibility of delivering homogenous dose distribution across a large target area [15–16]. Good field homogeneity can also be achieved by other active (using higher order optical elements, or beam ‘wobbling’) or passive methods (using scatterers) [17–19]. …”