VWIN - Fenêtres à vide haute performance pour lignes de faisceau de particules

A VWIN vacuum window is a thin foil between beamline vacuum and air, or between vacuum sectors. It is a beam window for charged-particle extraction, not a glass UHV viewport and not a consumer window vacuum.

Kapton is the common name for the nickel-metallized polyimide options. Those foils keep energy loss and scattering low. Diffusion-bonded titanium foil windows and 304 stainless-steel foil windows give UHV helium leak rates when the foil is also the vacuum boundary. The family is specified for protons, helium ions, and carbon ions at 30 MeV and above. Negative hydrogen ions strip to protons in the foil. Average beam current is up to 250 nA, with peaks up to 100 µA shorter than 2 µs.

Features

• 25 µm and 50 µm nickel-metallized polyimide (Kapton) foils for low scatter
• 15 µm and 25 µm titanium, and 50 µm 304 stainless steel, diffusion-bonded foil windows
• CF, KF, and ISO-K flanges: DN40CF, DN63CF, KF40, DN80ISO-K, and DN100ISO-K
• Helium leak rates from 1e-6 mbar l s-1 (25 µm polyimide) to 1e-9 mbar l s-1 (steel and 25 µm titanium)
• Each window is individually helium leak-tested

Applications

• Proton therapy exit window at the nozzle vacuum boundary, where the beam leaves vacuum into atmosphere
• Accelerator beam window between vacuum sectors on beamline components
• Thin-foil alternative to beryllium windows when a Be-free catalog part is required
• Proton therapy nozzles and research beamlines that need a documented leak rate and flange

Variants

Beam Interaction

Monte Carlo energy degradation (MeV) and neutron production (per incident proton) at 70 / 150 / 230 MeV.