IPAC2011 - List of Authors (Thomsen, H.D.)

Paper	Title	Page
THPS031	The Beam Expander System for the European Spallation Source	3487
	H.D. Thomsen, A.I.S. Holm, S.P. Møller ISA, Aarhus, Denmark
	At the European Spallation Source (ESS), neutrons are produced by high energy (2.5 GeV) protons impinging on a target. The lifetime of the target is highly dependent on the beam footprint. In general, the lower the average current density, the longer the lifetime of the target will be. A detailed study of two different expander systems suggested to be used to obtain the desired beam footprint has been undertaken. For reference, a system of quadrupole defocusing is used. The two systems under study are expansion of the beam by magnetic multipoles and raster scanning (painting) of the narrow linac beam over the target area. The designs, specifications, and comparative risks of the three systems will be described.

THPS050	The High Energy Beam Transport System for the European Spallation Source	3538
	A.I.S. Holm, S.P. Møller, H.D. Thomsen ISA, Aarhus, Denmark
	As part of the accelerator design update for the European Spallation Source (ESS), we present results from a detailed study of the High Energy Beam Transport (HEBT) line. The HEBT is a transport line around 100 m long, which connects the 2.5-GeV linac to the target. The linac will deliver a current of 50 mA, a pulse length of 2 ms and a repetition rate of 20 Hz, and losses are of utmost importance. Presumably, the HEBT will continue the 10 m period focusing structure of the linac. Two bends – overall, achromatic – will be needed to connect the different vertical levels between the linac and the target. A number of design aspects will be discussed here: space for future linac cryostats, the need and location for collimation, the location of the tuning beam dump and the associated beam optics, and the beam expander system, which provide the desired beam footprint on the target (see also separate contribution). A proposed design including options will be described together with hardware specifications.

Paper

Title

Page

The Beam Expander System for the European Spallation Source

3487

H.D. Thomsen, A.I.S. Holm, S.P. Møller
ISA, Aarhus, Denmark

At the European Spallation Source (ESS), neutrons are produced by high energy (2.5 GeV) protons impinging on a target. The lifetime of the target is highly dependent on the beam footprint. In general, the lower the average current density, the longer the lifetime of the target will be. A detailed study of two different expander systems suggested to be used to obtain the desired beam footprint has been undertaken. For reference, a system of quadrupole defocusing is used. The two systems under study are expansion of the beam by magnetic multipoles and raster scanning (painting) of the narrow linac beam over the target area. The designs, specifications, and comparative risks of the three systems will be described.

THPS050

The High Energy Beam Transport System for the European Spallation Source

3538

A.I.S. Holm, S.P. Møller, H.D. Thomsen
ISA, Aarhus, Denmark

As part of the accelerator design update for the European Spallation Source (ESS), we present results from a detailed study of the High Energy Beam Transport (HEBT) line. The HEBT is a transport line around 100 m long, which connects the 2.5-GeV linac to the target. The linac will deliver a current of 50 mA, a pulse length of 2 ms and a repetition rate of 20 Hz, and losses are of utmost importance. Presumably, the HEBT will continue the 10 m period focusing structure of the linac. Two bends – overall, achromatic – will be needed to connect the different vertical levels between the linac and the target. A number of design aspects will be discussed here: space for future linac cryostats, the need and location for collimation, the location of the tuning beam dump and the associated beam optics, and the beam expander system, which provide the desired beam footprint on the target (see also separate contribution). A proposed design including options will be described together with hardware specifications.