IPAC2011 - List of Authors (Osswald, F.R.)

Paper	Title	Page
THPS017	Simulation of Hollow Beam Formation at the Initial Part of RIB Transport Channel of SPIRAL2	3457
	N.Yu. Kazarinov JINR, Dubna, Moscow Region, Russia F.R. Osswald IPHC, Strasbourg Cedex 2, France
	The initial part of Radioactive Ion Beam (RIB) transport channel of SPIRAL2 consists of 2.45 GHz ECR Ion Source, focusing solenoid, triplet of quadrupole lenses and 90-degrees analyzing bending magnet. The supporting gas (Nitrogen) current of ECRIS used in RIB production has a value about 1 mA. The influence of the Nitrogen beam self-fields may leads to hollow beam formation in the transported ion species at the part of beam line placed after the focusing solenoid. This effect increases the RIB emittance and therefore complicates the RIB transport. In this report the numerical simulation of hollow beam formation is fulfilled. The threshold current of ECRIS supporting gas which gives a hollow beam formation of transported ions is defined. The influence of the beam neutralization is taking into account. The possible neutralization factor is found from results of simulation of GANIL Test Bench. The simulation of a variant of quadrupoles focusing system of the initial part of RIB transport channel is performed. The influence of the Nitrogen beam space charge on transport of 120+ ions with energy of 60 keV is studied.

Paper

Title

Page

Simulation of Hollow Beam Formation at the Initial Part of RIB Transport Channel of SPIRAL2

3457

N.Yu. Kazarinov
JINR, Dubna, Moscow Region, Russia
F.R. Osswald
IPHC, Strasbourg Cedex 2, France

The initial part of Radioactive Ion Beam (RIB) transport channel of SPIRAL2 consists of 2.45 GHz ECR Ion Source, focusing solenoid, triplet of quadrupole lenses and 90-degrees analyzing bending magnet. The supporting gas (Nitrogen) current of ECRIS used in RIB production has a value about 1 mA. The influence of the Nitrogen beam self-fields may leads to hollow beam formation in the transported ion species at the part of beam line placed after the focusing solenoid. This effect increases the RIB emittance and therefore complicates the RIB transport. In this report the numerical simulation of hollow beam formation is fulfilled. The threshold current of ECRIS supporting gas which gives a hollow beam formation of transported ions is defined. The influence of the beam neutralization is taking into account. The possible neutralization factor is found from results of simulation of GANIL Test Bench. The simulation of a variant of quadrupoles focusing system of the initial part of RIB transport channel is performed. The influence of the Nitrogen beam space charge on transport of 120+ ions with energy of 60 keV is studied.