SNS Linac Upgrade Plans for the Second Target Station

The Second Target Station (STS) upgrade proposal for the Spallation Neutron Source (SNS) [1] adds a short pulse, long wavelength neutron scattering station. In order to provide world-class neutron intensity at the additional station, the SNS linac beam power capability is doubled, to 2.8 MW. This will be accommodated by a 38% increase in the operational beam energy to 1.3 GeV and a 42% increase in beam current. The beam energy increase will be provided with the addition of 7 additional cyromodules and supporting RF equipment in space provided during the original SNS construction. Improving the ion source and reducing the chopping fraction will provide the beam current increase. Increases in the RF and high voltage modulator systems are needed to accommodate the additional beam loading. Initial plans are presented.