title: Low-energy beam transport studies supporting the spallation neutron source 1-MW beam operation.
abstract: The H(-) injector consisting of a cesium enhanced RF-driven ion source and a 2-lens electrostatic low-energy beam transport (LEBT) system supports the spallation neutron source 1 MW beam operation with ∼38 mA beam current in the linac at 60 Hz with a pulse length of up to ∼1.0 ms. In this work, two important issues associated with the low-energy beam transport are discussed: (1) inconsistent dependence of the post-radio frequency quadrupole accelerator beam current on the ion source tilt angle and (2) high power beam losses on the LEBT electrodes under some off-nominal conditions compromising their reliability.
authors.affiliation: Spallation Neutron Source, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA. hanb@ornl.gov
authors.forename: B X
authors.initials: BX
authors.lastname: Han
authors.forename: T
authors.initials: T
authors.lastname: Kalvas
authors.forename: O
authors.initials: O
authors.lastname: Tarvainen
authors.forename: R F
authors.initials: RF
authors.lastname: Welton
authors.forename: S N
authors.initials: SN
authors.lastname: Murray
authors.forename: T R
authors.initials: TR
authors.lastname: Pennisi
authors.forename: M
authors.initials: M
authors.lastname: Santana
authors.forename: M P
authors.initials: MP
authors.lastname: Stockli