Abstract
The spallation neutron source (SNS) is a second generation pulsed neutron source and designed
to provide a 1-GeV, 1.44-MW proton beam to a mercury target for neutron production. Since the
commissioning of the accelerator complex in 2006, the SNS has started its operation for neutron
production and beam power ramp-up has been in progress toward the design goal. All subsys-
tems of the SNS were designed and developed for substantial improvements compared to existing
accelerators because the design beam power is almost an order of magnitude higher compared to
existing neutron facilities and the achievable neutron scattering performance will exceed present
sources by more than a factor of 20 to 100. In this paper, the operational experiences with the
SNS Superconducting Linac (SCL), Power Ramp-up Plan to reach the design goal and the Power
Upgrade Plan (PUP) will be presented including machine, subsystem and beam related issues.
