Speaker
Description
The Los Alamos Neutron Science Center (LANSCE) has been a cornerstone of pulsed neutron science and national security applications for over fifty years, delivering 800 MeV proton beams to multiple user facilities including the Lujan Center’s 1L neutron spallation target. The Lujan Center’s neutron spallation performance, particularly for high-resolution and high-flux experiments, places stringent demands on accelerator beam quality, timing structure, and reliability. However, much of the LANSCE front-end, including the dual 750-kV Cockcroft-Walton injectors and original low-energy beam transport (LEBT) systems, is now far beyond its design lifetime. These legacy systems limit achievable current, complicate precision bunching, and contribute to reliability risks that directly impact beam delivery to 1L and other neutron sources.
The LANSCE Accelerator Modernization Project (LAMP) addresses these challenges by redefining the front end with modern accelerator design principles to meet future neutron spallation requirements. LAMP replaces obsolete front-end components up to 100 MeV with a new suite of H⁺ and H⁻ ion sources, improved LEBT lines, a dual-species 3 MeV Radio-Frequency Quadrupole (RFQ), advanced Medium-Energy Beam Transport (MEBT), and a modern 201.25 MHz drift-tube linac. The upgraded front end enables higher beam currents (targeting ~35 mA), enhanced transverse and longitudinal matching to the Proton Storage Ring (PSR), precise pulse shaping, and improved control of satellite bunches and dark current (key factors for consistent, high-quality beam delivered to the Lujan 1L target).
Design requirements for the new front end are driven by the needs of the neutron spallation program: robust dual-species operation, retention of flexible macro-pulse structures, and reduction of tune sensitivity to source and transport variations. LAMP’s front-end architecture incorporates fast chopping with stringent rise/fall times to shape micro-bunch trains for the PSR, matching optics based on advanced beam dynamics studies, and comprehensive diagnostics to preserve beam emittance and minimize losses. Realizing these requirements will ensure that the Lujan 1L beamline continues to support neutron science with reliable, high-intensity, and high-quality beams well into the next decades of operation.