Beam Dump g. mornacchi

Beam Dump Temporary Beam Dump

Why ? RP report attached to agenda Assume 5E5 pbar/sec (potentially 3E7 pbar/60 sec) from ELENA If (much) less than the nominal, we can probably argue 100% annihilate on last vacuum pipe flange Need about 6- 7 m to remain below the limit of supervised area (<3 uSv/h) While the experimental area is a “low occupancy area” (15 uSv/h), the platforms are “permanent workplaces” (< 3uSv/h) The platform is less than 7m in both (final, temporary) cases What counts (in addition to the intensity of the source) : type of particles, their energy, distance In this case the equivalent dose rate is dominated by “high energy” pions No need for a beam dump when taking H- from ELENA

How 100% pbars annihilate on the last flange of the beam pipe (either the end of the decelerator, or the pipe from the switchyard). The flange is the “beam stopper” Surround the last 20 cm of the beam pipe with concrete blocks Temporary location : 40x40x40 cm3 A “wide” geometry (e.g. 40 cm opening to feed the beam pipe) may be acceptable (see additional slide for the geometry) Final location (closer to platform) 80 (height)x60 (depth) x 40 (wide) cm3

when Can be built and installed by EN/EA (Francois Butin) At a “relatively” small cost, for the concrete blocks (~< 1kCHF) Francois will need about 2-3 weeks to get organized In final position needs the switchyard at the earliest ~ spring 2018 (anyhow before 2018 pbars) Will we need it in the temporary location (i.e. in 2017)? We ought to define what we want in 2017 When we get pbars from ELENA? What we do with the pbars (detectors at end of decelerator?) Maybe we can avoid the temporary beam dump given the expected low intensity not necessary with H- To argue we have to have a well defined plan (see above)

Additional slides

Geometries (temporary dump) F. Cerutti, A Ciccotelli, C. Theis Stainless-steel beam pipe (rint=5 cm; rext=5.3 cm) Stainless-steel cylindrical beam dump (r=5.3 cm and 1 cm thick) Shielding geometry 1 40x40x40 cm3 concrete Cylindrical opening (r=7cm; L=20cm) Shielding geometry 2 90x90x40 cm3 concrete Wide opening of 50x50x20 cm3