LINAC2014 - List of Authors (Scrivens, R.)

Paper	Title	Page
TUPP036	Space Charge Compensation in the Linac4 LEBT for Three Injected Gas Types	510
TUPOL012	use link to see paper's listing under its alternate paper code
SUPG028	use link to see paper's listing under its alternate paper code
	C.A. Valerio, R. Scrivens CERN, Geneva, Switzerland N. Chauvin CEA/IRFU, Gif-sur-Yvette, France
	The space charge of unbunched, high intensity beams can be compensated by the trapping of charged particles in the potential well of the beam. The source of these secondary charge particles can be the residual gas in the beam line. The effect is important in the Low energy beam transport (LEBT) regions. At CERN’s Linac4, the LEBT transports a pulsed 45keV H⁻ beam, which is compensated by the positive ions, created by collision of the beam with the neutral gas in the beam pipe. The rise time and amount of compensation may be varied by the density of neutral gas and the type of gas used (through the cross-section for ion production and the mass of the resulting ion). In this paper we present measurement results for the transport of the beam at the Linac4 LEBT with the addition of hydrogen, nitrogen and krypton gases into the line, and compare them with simulations of the beam dynamics including the effect of compensating positive ions . The H⁻ beam is provided by a cesiated 2MHz RF ion source with an external solenoidal antenna, operating with 600us pulses at 0.8Hz repetition rate.
	Slides TUPP036 [4.084 MB]
	Poster TUPP036 [1.356 MB]

Paper

Title

Page

TUPP036

Space Charge Compensation in the Linac4 LEBT for Three Injected Gas Types

510

TUPOL012

use link to see paper's listing under its alternate paper code

SUPG028

use link to see paper's listing under its alternate paper code

C.A. Valerio, R. Scrivens
CERN, Geneva, Switzerland
N. Chauvin
CEA/IRFU, Gif-sur-Yvette, France

The space charge of unbunched, high intensity beams can be compensated by the trapping of charged particles in the potential well of the beam. The source of these secondary charge particles can be the residual gas in the beam line. The effect is important in the Low energy beam transport (LEBT) regions. At CERN’s Linac4, the LEBT transports a pulsed 45keV H⁻ beam, which is compensated by the positive ions, created by collision of the beam with the neutral gas in the beam pipe. The rise time and amount of compensation may be varied by the density of neutral gas and the type of gas used (through the cross-section for ion production and the mass of the resulting ion). In this paper we present measurement results for the transport of the beam at the Linac4 LEBT with the addition of hydrogen, nitrogen and krypton gases into the line, and compare them with simulations of the beam dynamics including the effect of compensating positive ions . The H⁻ beam is provided by a cesiated 2MHz RF ion source with an external solenoidal antenna, operating with 600us pulses at 0.8Hz repetition rate.

Slides TUPP036 [4.084 MB]

Poster TUPP036 [1.356 MB]