high intensity proton beam line

Beam Line: Target station E to Beam Dump Target station E

high intensity proton beam line This last section of the 590 MeV High Intensity Proton Beam Channel is 17 m long and consists of 2 quadrupoles, 1 bending magnet (switch yard for SINQ) used as vertical steering magnet, 1 horizontal steering magnet, 2 pairs of profile monitors, 1 current monitor, 4 collimators and a beam dump (see Fig.1, 57 kB). Target E adds 8.5 mrad ( 1 sigma) to the divergence of the beam. The aperture (24 cm inside the quadrupoles) is large enough to allow the beam via intermediate waists to grow to a diameter of 4sigma= 40 cm in both directions at the location of the beam dump ( Fig.2: 13 kB ) .
high intensity proton beam line As can be seen from Fig. 1 the different components are arranged as vertically removable blocks with up to 2 meters of iron shielding on top of them and their vacuum chambers connected together with a total of 24 inflatable cushion sealings ( see Fig. 3, 51 kB). (Well visible on this picture are the two concentric inflatable cushions of one side made out of steel foil with a grove in between for differential pumping.) This concept has been developed at PSI by H. Frei et al.
high intensity proton beam line The collimators 2 and 3 are elliptical (vertical half axis = 80 mm, horizontal half axis = 40 mm) and conical (vertex at the location of Target E) to bring the losses in the quadrupole duplett (QHG21/QHG22) to a reasonable value. Collimators 0 and 1 protect the mirror plates of the neighboring half quadrupoles for the secondary beam lines. All collimators are made out of copper and are water cooled.
high intensity proton beam line The sum of all proton losses along the first 10 m of this section are 43 %. (With the target E length reduced from 60 mm to 40 mm these losses are only 30 %). Collimator 1 and 2 and the 3 first sections of the beam dump have electrically insulated electrodes (MHB's, 4 thin nickel foil segments each) fastened to it to detect - position sensitive - the amount of protons dumped on them. The stopping of a large amount of protons (~ 20 %) in the collimators produces a considerable halo, which does not matter to much, if the beam is not deflected with the bending magnet (AHL) towards SINQ, because in this region all components are radiation hardened. In case one component here goes defective, it may be removed and repaired by remote handling (repair work takes place in a special hot cell in the ATEC region). For the transportation of the highly activated components like targets, collimators and beam dump segments an iron shielded bottle is available.

Urs Rohrerhigh intensity proton beam line Last updated by Urs Rohrer on 27-Mar-2006