• C. Jahnke, A.A. Malafronte, M.N. Martins, T.F. Silva, V.R. Vanin
  USP/LAL, Sao Paulo

Funding: FAPESP, CNPq

The IFUSP Microtron transport line guides the 5 MeV electron beam from the booster to the main microtron, where it can be accelerated up to 38 MeV in steps of 0.9 MeV. A few meters after leaving the main microtron, the beam is guided to the experimental hall, which is located 2.7 m below the accelerator room. The beam leveling is made by two 90° bending magnets. In the experimental hall there is a switching magnet to drive the beam to two different experimental lines. Each of these lines has another 90° bending magnet. These magnets were designed, constructed and characterized. In this work we present the analysis of the field distribution of these 90° bending magnets. Comparison between field simulation and data from field mapping is presented. We also present a reproducibility analysis where the field distributions of two twin magnets are presented.

• T.F. Silva, R. Lima, A.A. Malafronte, M.N. Martins, A.J. Silva, V.R. Vanin
  USP/LAL, Sao Paulo

Funding: FAPESP, CNPq

In this work we describe the design of the OTR monitors that will be used to measure beam parameters of the IFUSP Microtron electron beam. The OTR monitor design must allow for efficiency in the entire energy range (from 5 MeV up to 38 MeV in steps of 0.9 MeV), and the devices are planed to monitor charge distribution, beam energy and divergence. An exception is made for the OTR monitor to the 1.7 MeV beam line, which is to be used to monitor only the beam charge distribution at the exit of the linac injector. The image acquisition system is also presented.

• T.F. Silva, Z.O. Guimarães-Filho, C. Jahnke, M.N. Martins
  USP/LAL, Sao Paulo

Funding: FAPESP, CNPq

In this work we describe a model to study the effect of charge saturation in phosphor screens in the determination of electron beam profiles. It is shown that the charge saturation introduces systematic errors in the beam diameter determination, since it tends to increase the observed beam diameter. The study is made supposing a Gaussian beam profile and a saturation model to the charge response of the phosphor material. The induced errors increase for higher currents and/or narrow beams. A possible correction algorithm that can be applied to some measurements is presented, together with a brief discussion about the consequences of these systematic errors in emittance measurements.

• T.F. Silva, A.L. Bonini, C. Jahnke, R. Lima, M. Lucena, A.A. Malafronte, M.N. Martins, L. Portante, A.J. Silva, V.R. Vanin
  USP/LAL, Sao Paulo

Funding: FAPESP, CNPq

The Instituto de Física da Universidade de São Paulo (IFUSP) is building a two-stage 38 MeV continuous wave racetrack microtron. This accelerator consists of a linac injector that delivers a 1.7 MeV beam to a microtron (booster) with 5 MeV exit energy. A transport line guides the beam to the main microtron to be accelerated to energies up to 38 MeV in steps of 0.9 MeV. This work describes the commissioning of the linac injector that comprises the first two accelerating structures of the IFUSP Microtron. A provisional beam line was built at the end of the linac to provide energy and current measurements. We also present results concerning RF power, RF phase, and temperature control of the accelerating structures. The first results of the chopper and buncher systems are also presented.