Development of a Tandem-Electrostatic-Quadrupole facility for Accelerator-Based Boron Neutron Capture Therapy

A.J. KREINER; J. BERGUEIRO; A.A. BURLON; H. DI PAOLO; W. CASTELL; V. THATAR VENTO; D. CARTELLI; P. LEVINAS; J.M. KESQUE; A.A. VALDA; J.C. ILARDO; M. BALDO; J. ERHARDT; M.E. DEBRAY; H.R. SOMACAL; L. ESTRADA; J.C. SUAREZ SANDIN; M. IGARZABAL; H. HUCK; M. REPETTO; M. OBLIGADO; J. LELL; J. PADULO; D.M. MINSKY; M. HERRERA; S.R. GONZALEZ; M.E. CAPOULAT

Buenos Aires

Congreso; 14th International Congress on Neutron Capture Therapy; 2010

International Society for NeutronCapture Therapy

Presentación Oral (A.J. Kreiner)Introduction: We shall highlight in this paper the present status of an ongoing project to develop a folded Tandem-Electrostatic-Quadrupole (TESQ) accelerator facility for Accelerator-Based Boron Neutron Capture Therapy (AB-BNCT) based on the 7Li(p,n)7Be reaction at 2.4MeV. The machine being currently constructed is a folded TESQ with a terminal at 0.6MV and 30mA capability as a smaller scale prototype, due to building limitations. Since the concept is modular the same structure will be used for the 1.2MV final accelerator. We report here on the progress achieved in a number of different areas, more closely linked to the hardware of the facility. Additionally aspects related to the electrostatic field assessment, beam transport, tubes, ion sources, beam shaping assembly and patient treatment room, treatment planning, on-line dose determination system and alternative neutron producing reactions will be presented in detail in other contributions to this conference. Materials and Methods: The TESQ’s accelerating column consists of a series of stacked cylindrical boxes which are separated by 200kV and 40cm air gaps (a total of 4 to reach 0.6MV, the first one being at ground potential). This column houses the up- and down-going acceleration tubes with the quadrupoles inside. The implicated working areas include mechanical and electromechanical components such as alternators and high-voltage power supplies, electrostatic simulations, acceleration and beam transport modules (tubes) simulated using 3D finite element selfconsistent codes, construction of tubes, ion sources, neutron production target and cooling devices, control systems, strippers, etc. Results and Discussion: The mechanical and electromechanical structure is completed, including support structure, insulating posts and rotating shafts, alternators and electrostatic shields for the 600kV prototype. The machine has been built as a right cylinder of 2.5m diameter crowned at its upper ending by a high voltage dome at 0.6MV. The column consists of a series of stacked cylindrical boxes (35cm in height), surrounded by semi-toroidal surfaces, which are separated by 200kV in voltage and 40cm air gaps. The boxes house 12kVA alternators, driven by vertical insulating rotating shafts which are attached to electric motors placed at ground potential, that provide the necessary power to feed the high-voltage supplies (100kV and 60mA units also housed within the boxes) which will build up the high-voltage for the installation. These boxes are traversed vertically by the up- and down-going acceleration tubes, which are made of slices of borosilicate glass and stainless steel electrodes. All of the supporting elements, like base structures, insulating posts and rotating shafts have already been constructed and tested, and the mechanical structure has been assembled and stability and vibration tests have been run. Different other developments will be highlighted like high current ion sources, tubes, vacuum and control systems and high power neutron production targets.