IPHC, Strasbourg Cedex 2, France
IHEP, Beijing, People's Republic of China
The ESS'SB project foresees the production of a very intense neutrino beam to enable the discovery of leptonic CP violation. In addition to the neutrinos, a copious number of muons that could be used by a future Neutrino Factory and a muon collider will also be produced at the same time. This facility will use the world's most intense pulsed spallation neutron source, the European Spallation Source (ESS) in Lund. Its LINAC is expected to be operational by 2023, producing 2 GeV protons with a power of 5 MW. The primary proton beam line completing the linear accelerator will consist of one or several accumulator rings and a proton beam switchyard. The secondary beam line producing neutrinos and muons will consist of a four-horn target station, a decay tunnel and a beam dump. To detect the produced neutrinos a far megaton scale Water Cherenkov detector will be placed at a baseline of about 500 km in one of the existing active mines in Sweden. The estimation of the energy deposited and the activation within this secondary beam line are discussed in this paper.
ORNL, Oak Ridge, Tennessee, USA
To better understand the mechanical impact of the proton beam on the lifetime on Spallation Neutron Source (SNS*) mercury-filled, stainless steel targets, these targets are now instrumented with optical and metal strain sensors, temperature sensors, and accelerometers. The strain and temperature sensors are placed inside the target vessel, between the water shroud and mercury vessel, while the accelerators are placed outside on the target mount and on the mercury return line. We now have data from four targets. The first instrumented target used regular multimode optical sensors, while later targets have used radhard multimode sensors. We are also developing super-radhard single-mode optical strain sensors to get data further into the production cycle. In this paper, we describe the data-acquisition system, compare the measured strain to the simulated strain for the different targets, estimate the survivable radiation level for each type of sensor, and discuss the implications of the results on the lifetime of the target.
