ABSTRACT
During commissioning of the 6.7 MeV Low-Energy Demonstration Accelerator (LEDA) radiofrequency quadrupole (RFQ), we used a four-quadrupole high energy beam transport (HEBT) line to transport the beam from the RFQ exit to the beam stop. Quadrupole scans in the HEBT were used to characterize the transverse phase space at the RFQ exit. ln this procedure, only the two quadrupoles immediately downstream of the RFQ exit were used. Quadrupole Q I focuses in the y-direction and Q2 focuses in x. For characterizing the beam in the xdirection, Q2 was varied and the beam was observed at the wire scanner, which was about 2.5 m downstream, just before the beam stop. The strength of Ql was fixed at a value that ensured that the beam was contained in both directions for all values of Q2. For characterizing the y-direction, Q I was varied with Q2 fixed.
