The SPES (Selective Production of Exotic Species) facility purposes are the production of radioactive beams (RIBs) by ISOL technique, the production and the research on innovative radioisotopes and experiments with high intensity neutron beams. For these reasons, the 70p cyclotron, designed by BEST Cyclotron Systems Inc. (BCSI), has been installed at Laboratori Nazionali di Legnaro (LNL): it is a machine able to produce a beam current up to 700 μA shared into two extraction channels. Beams at the energy values of 35 MeV, 50 MeV and 70 MeV have to be transported to the experimental areas with specific properties and minimizing the beam losses. Here, the main features of the needed beamlines are described. BEAMLINES OF THE SPES PROJECT The core of the SPES project is the 70p cyclotron, a 4 sectors machine with room temperature coils, designed to accelerate H ions. The extraction by stripping method allows the beam current sharing into two extraction channels: it is possible to carry out simultaneously the production of radioactive ions and other applications [1]. Figure 1 shows the layout of the underground floor of the SPES building. The central vault (A1) houses the 70p cyclotron and it is surrounded by different experimental areas: in particular, there are three bunkers shielded for receiving high power beam (up to 50 kW). Figure 1 reports the beamline for the beam transport to the ISOL target (L1), which was designed by BCSI [2], and the beamlines L3b-L3c and L2, dedicated to the SPES applications. The beamline L1 is actually operational and, with the second extraction channel, it is included in the commissioning of the 70p cyclotron. As concern the other beamlines, the main properties of the achieved solutions are here described: these beamlines have the same initial elements of the beamline L1, from the combo magnet at the cyclotron extraction to the first switching magnet; the new designs have to take into account this fixed part and the preliminary results related to the first machine operations. The main requirement for each configuration is the minimization of the beam losses along the beam path: the allowable limit is 1%. BEAM TRANSPORT TO ISOL AREA The beamline to the ISOL area was installed in the vault in May 2015. The beamline design was completed to satisfy all the requirements needed for the ISOL facility, that is, a final RMS spot size around 4 mm. For the cyclotron commissioning by using the beam dumper designed by LNL SPES target team [3], new tunes of the 4 couples of quadrupoles were required, in order to increase the RMS spot size in the range 8 – 12 mm and, then, to optimize the power distribution in the inner surfaces of the device. A summary of the simulation results is reported in Table 1, for the minimum and the maximum values of the RMS spot size: the beam losses are less than the required limit. Table 1: Simulation Results of the L1 Beamline Tunes Up to now, the L1 beamline has been fully tested only by using 70 MeV beam and the 4-jaw collimators placed just after the combo magnet have been used to reduce the beam halo. Furthermore, the wobbler system placed just before the A6 bunker entrance has been activated in order to get a uniform beam distribution and to avoid thermal stresses of the beam dumper. These effects have to be included in the complete study of the performance of the L1 beamline and are useful data for the improvement of the design of the new beamlines. RADIOISOTOPE PRODUCTION LARAMED (LAboratorio per la Produzione di RAdionuclidi per la MEDicina) is the proposal of LNL for the production of innovative radiopharmaceutical and conventional radionuclides [4]. The beamlines L3b and L3c, which satisfy the requirements described in table 2, share all the elements in A1 hall, then a 45 deg switching magnet is used to bend the beam in the low current experimental area. Table 2: Main Features of the LARAMED Beamlines L3b L3c Energy range 35 – 70 MeV 35 -70 MeV Average current 300 μA < 1 μA Beam spot size (RMS sigma) 3 mm 3 – 4 mm Optic layout 3 quad doublets 1 switching magnet, 2 quad doublets Energy [MeV] 35 50 70 RMS spot [mm] 8 11 8 11 8 11 Q1 [T/m] 4.99 4.99 6.31 6.31 5.06 4.91 Q2 [T/m] -5.41 -5.41 -6.69 -6.69 -6.68 -7.66 Q3 [T/m] -4.35 -4.30 -5.25 -5.15 -5.45 -5.56 Q4 [T/m] 3.05 3.19 3.81 3.81 3.20 3.72 Q5 [T/m] 3.60 3.87 4.51 4.98 5.82 6.84 Q6 [T/m] -5.06 -5.01 -6.24 -6.52 -7.25 -8.41 Q7 [T/m] -4.04 -3.81 -4.64 -4.31 -5.90 -4.99 Q8 [T/m] 3.13 2.65 3.34 2.97 4.38 3.35 Losses [%] 0.12 0.22 0 0.19 0.02 0.1 Proceedings of Cyclotrons2016, Zurich, Switzerland MOP04 Theory, Models and Simulations ISBN 978-3-95450-167-0 53 C op yr ig ht © 20 16 C C -B Y3. 0 an d by th e re sp ec tiv e au th or s Figure 1: Layout of the SPES facility beamlines. The beamline L1 to transport the beam to the ISOL bunker A6 is under commissioning. The first 45 deg switching magnet along the L1 beamline allows the sharing of the proton beam between the three experimental areas dedicated to experiments with high intensity neutron beams (A9) and the radioisotope production (RI3 bunker and the space aside). In particular, the L3b beamline follows a straight path from the first 45 deg switching magnet in the A1 vault up to the RI3 bunker: the beam transport is completed by using three couples of quadrupoles; the total line length is 20.8 m. The additional elements needed to complete the L3b beamline have the same properties of the existing L1 beamline elements, which have a maximum gradient value of 10 T/m and an aperture of 102 mm for each quadrupoles. The proposed solutions for the quadrupole tunes and the related envelopes are reported in Table 3 and Fig. 2 respectively: the beam losses for each configuration are less than 0.1%. Table 3: Quadrupole Tune of the L3b Beamline The L3c beamline has the same elements of L3b beamline in A1 hall, while in A9 hall it needs a 45 deg switching magnet and a quadrupole couple; the total length is about 14.85 m. By using suitable tunes it is possible to produce at the target beam spot with RMS size in the range 3 – 5 mm. In table 4, only the solutions able to obtain a beam spot with a RMS sigma of 3 mm are shown. The beam losses along these configurations are less than 0.1% (see Fig. 3) and occur mainly in the vacuum chamber of the two switching magnets. Energy [MeV] 35 50 70 Q1 [T/m] 4.682 5.740 8.175 Q2 [T/m] -5.615 -6.639 -8.680 Q3 [T/m] -4.422 -4.732 -5.144 Q4 [T/m] 3.831 3.444 3.590 Q5 [T/m] 2.556 2.445 2.562 Q6 [T/m] -2.113 -2.314 -2.301 Q7 [T/m] -2.993 -3.112 -3.722 Q8 [T/m] 3.944 4.003 3.968 50 MeV 35 MeV