LINAC2014 - List of Authors (Pisent, A.)

Paper	Title	Page
MOPP087	Construction of the Modules of the IFMIF-EVEDA RFQ	257
	A. Pepato, E. Fagotti, F. Grespan, A. Palmieri, A. Pisent, C. R. Roncolato INFN/LNL, Legnaro (PD), Italy R. Dima, L. Ferrari, E. Udup INFN- Sez. di Padova, Padova, Italy A. Margotti INFN-Bologna, Bologna, Italy P. Mereu INFN-Torino, Torino, Italy
	The IFMIF project aims to produce an intense neutron flux to test and qualify materials suitable for the construction of fusion power plants. We are working on the engineering validation phase of the project, which consists on the construction of a linear accelerator prototype to be installed and commissioned in Rokkasho. The RFQ is composed of 18 modules flanged together for a total length of 9.8m designed to accelerate the 125mA D⁺ beam to 5MeV at a frequency of 175MHz. The mechanical specifications are very challenging, tight tolerances are required on the machining and on the brazing process. The line is subdivided into 3 Super Modules of 6 modules each. The production of the High Energy portion has been completed and delivered, while the Low Energy one is performing the acceptance test. They were commissioned to external firms. The production of the Intermediate Energy portion has been done in house (INFN) and will be commissioned soon. The 1st modules (16, 17 and 2) were produced adopting 2 brazing steps, while for all the remaining ones we adopted a single brazing step. In this paper the production status and the development of the brazing procedure will be described.

MOPP088	MUNES a Compact Neutron Source for BNCT and Radioactive Wastes Characterization	261
	A. Pisent, P. Colautti, E. Fagotti INFN/LNL, Legnaro (PD), Italy
	At INFN LNL (Legnaro Italy) it has been built a high intensity Radio Frequency Quadrupole (RFQ) structure, able to produce a 5 MeV proton beam of 30 mA. Coupled with a Be target such a beam can generate a neutron flux of 10¹⁴ n/s, with a spectrum centered in the MeV region (that has been recently characterized in detail at LNL accelerators). This neutron flux can be moderated to generate a thermal or epithermal source for BNCT with very little contamination of energetic form energetic neutron and gamma. Since the approval of MUNES project (in 2012) the high technology issues related to a compact neutron source to be installed in an Hospital environment have been faced. In particular for the powering of the accelerating structure an innovative system, completely based on solid state amplifiers, has been developed and ordered to industry. An outline of MUNES design and the status of the project will be given in the paper.

TUPP093	The Couplers for the IFMIF-EVEDA RFQ High Power Test Stand at LNL: Design, Construction and Operation	643
	E. Fagotti, L. Antoniazzi, M.G. Giacchini, F. Grespan, M. Montis, A. Palmieri, A. Pisent, C. R. Roncolato INFN/LNL, Legnaro (PD), Italy
	In order to assess the critical aspects of the IFMIF-EVEDA RFQ construction procedure and operation, it was decided to perform a High Power Test of a subset of the RFQ consisting in its last 550 mm three modules (out of 18) plus a Prototype Module, 390 mm long, used as RF plug. These modules are going to be tested at full power in CW of INFN LNL Labs, in the so-called RFQ High Power Test Stand. For such a purpose, a RF tube-based amplifier capable of 220 kW CW output power at the operational frequency of 175 MHz was purchased from an Italian company. A critical component of this test is the RF power coupler. Therefore INFN-LNL developed a design of two identical water-cooled loop antenna couplers, built with OFE copper and vacuum sealed with a commercially available 6”1/8 Alumina planar window. These couplers were tested separately on an aluminium coupling cavity. In particular one of them acts as a power feeder, while the other one, connected with a 200 kW water-cooled load, acts as a receiver. In this paper, the main aspects of the design, construction and tests performed on the couplers and coupling cavity will be described.

THPP044	ESS Normal Conducting Linac Status and Plans	948
	A. Ponton, B. Cheymol, R. De Prisco, M. Eshraqi, R. Miyamoto, E. Sargsyan ESS, Lund, Sweden G. Bourdelle, M. Desmons, A. France, O. Piquet, B. Pottin CEA/DSM/IRFU, France I. Bustinduy, P.J. González, J.L. Muñoz, I. Rueda, F. Sordo ESS Bilbao, Bilbao, Spain L. Celona, S. Gammino, L. Neri INFN/LNS, Catania, Italy M. Comunian, F. Grespan, A. Pisent, C. R. Roncolato INFN/LNL, Legnaro (PD), Italy P. Mereu INFN-Torino, Torino, Italy
	The ESS Normal Conducting (NC) linac is composed of an ion source, a Low Energy Beam Transport line, a Radio Frequency Quarupole (RFQ), a Medium Energy Beam Transport Line (MEBT) and a Drift Tube Linac (DTL). It creates, bunches and accelerates the proton beam up to 90 MeV before injecting into the superconducting linac which will deliver a 5 MW beam onto the neutron production target. The construction of the NC linac is part of a broad collaboration involving experts of various Labs in Europe. The technical chalenges and the collaboration strategy for the NC linac will be presented.

THPP086	ESS DTL Error Study	1047
	M. Comunian, F. Grespan, A. Pisent INFN/LNL, Legnaro (PD), Italy
	The Drift Tube Linac (DTL) of the European Spallation Source (ESS) is designed to operate at 352.2 MHz with a duty cycle of 4% (3 ms pulse length, 14 Hz repetition period) and will accelerate a proton beam of 62.5 mA pulse peak current from 3.62 to 90 MeV. The error study is decisive to define the DTL manufacturing tolerances and to evaluate its robustness. In this paper the DTL performances are shown.

THPP087	ESS DTL Design and Drift Tube Prototypes	1050
	F. Grespan, M. Comunian, A. Pisent, M. Poggi, C. R. Roncolato INFN/LNL, Legnaro (PD), Italy P. Mereu INFN-Torino, Torino, Italy
	The Drift Tube Linac (DTL) for the ESS accelerator will accelerate protons up to 62.5 mA average pulse current from 3.62 to 90 MeV. The 5 tanks composing the DTL are designed to operate at 352.2 MHz in pulses of 2.86 ms long with a repetition rate of 14 Hz. The accelerating field is around 3.1 MV/m, constant in each tank. Permanent magnet quadrupoles (PMQs) are used as focusing element in a FODO lattice. The empty drift tubes accommodate Electro Magnetic Dipoles (EMDs) and Beam Position Monitors (BPMs) in order to implement beam corrective schemes. A complete set of Drift Tubes is under construction that is BPM, EMD and PMQ types. These prototypes are aimed to validate the design with the involved integration issues of the various components, as well as the overall technological and assembly process. This paper presents the main mechanical choices and the status of the prototyping program of the Drift Tubes.

Paper

Title

Page

Construction of the Modules of the IFMIF-EVEDA RFQ

257

A. Pepato, E. Fagotti, F. Grespan, A. Palmieri, A. Pisent, C. R. Roncolato
INFN/LNL, Legnaro (PD), Italy
R. Dima, L. Ferrari, E. Udup
INFN- Sez. di Padova, Padova, Italy
A. Margotti
INFN-Bologna, Bologna, Italy
P. Mereu
INFN-Torino, Torino, Italy

The IFMIF project aims to produce an intense neutron flux to test and qualify materials suitable for the construction of fusion power plants. We are working on the engineering validation phase of the project, which consists on the construction of a linear accelerator prototype to be installed and commissioned in Rokkasho. The RFQ is composed of 18 modules flanged together for a total length of 9.8m designed to accelerate the 125mA D⁺ beam to 5MeV at a frequency of 175MHz. The mechanical specifications are very challenging, tight tolerances are required on the machining and on the brazing process. The line is subdivided into 3 Super Modules of 6 modules each. The production of the High Energy portion has been completed and delivered, while the Low Energy one is performing the acceptance test. They were commissioned to external firms. The production of the Intermediate Energy portion has been done in house (INFN) and will be commissioned soon. The 1st modules (16, 17 and 2) were produced adopting 2 brazing steps, while for all the remaining ones we adopted a single brazing step. In this paper the production status and the development of the brazing procedure will be described.

MOPP088

MUNES a Compact Neutron Source for BNCT and Radioactive Wastes Characterization

261

A. Pisent, P. Colautti, E. Fagotti
INFN/LNL, Legnaro (PD), Italy

At INFN LNL (Legnaro Italy) it has been built a high intensity Radio Frequency Quadrupole (RFQ) structure, able to produce a 5 MeV proton beam of 30 mA. Coupled with a Be target such a beam can generate a neutron flux of 10¹⁴ n/s, with a spectrum centered in the MeV region (that has been recently characterized in detail at LNL accelerators). This neutron flux can be moderated to generate a thermal or epithermal source for BNCT with very little contamination of energetic form energetic neutron and gamma. Since the approval of MUNES project (in 2012) the high technology issues related to a compact neutron source to be installed in an Hospital environment have been faced. In particular for the powering of the accelerating structure an innovative system, completely based on solid state amplifiers, has been developed and ordered to industry. An outline of MUNES design and the status of the project will be given in the paper.

TUPP093

The Couplers for the IFMIF-EVEDA RFQ High Power Test Stand at LNL: Design, Construction and Operation

643

E. Fagotti, L. Antoniazzi, M.G. Giacchini, F. Grespan, M. Montis, A. Palmieri, A. Pisent, C. R. Roncolato
INFN/LNL, Legnaro (PD), Italy

In order to assess the critical aspects of the IFMIF-EVEDA RFQ construction procedure and operation, it was decided to perform a High Power Test of a subset of the RFQ consisting in its last 550 mm three modules (out of 18) plus a Prototype Module, 390 mm long, used as RF plug. These modules are going to be tested at full power in CW of INFN LNL Labs, in the so-called RFQ High Power Test Stand. For such a purpose, a RF tube-based amplifier capable of 220 kW CW output power at the operational frequency of 175 MHz was purchased from an Italian company. A critical component of this test is the RF power coupler. Therefore INFN-LNL developed a design of two identical water-cooled loop antenna couplers, built with OFE copper and vacuum sealed with a commercially available 6”1/8 Alumina planar window. These couplers were tested separately on an aluminium coupling cavity. In particular one of them acts as a power feeder, while the other one, connected with a 200 kW water-cooled load, acts as a receiver. In this paper, the main aspects of the design, construction and tests performed on the couplers and coupling cavity will be described.

THPP044

ESS Normal Conducting Linac Status and Plans

948

A. Ponton, B. Cheymol, R. De Prisco, M. Eshraqi, R. Miyamoto, E. Sargsyan
ESS, Lund, Sweden
G. Bourdelle, M. Desmons, A. France, O. Piquet, B. Pottin
CEA/DSM/IRFU, France
I. Bustinduy, P.J. González, J.L. Muñoz, I. Rueda, F. Sordo
ESS Bilbao, Bilbao, Spain
L. Celona, S. Gammino, L. Neri
INFN/LNS, Catania, Italy
M. Comunian, F. Grespan, A. Pisent, C. R. Roncolato
INFN/LNL, Legnaro (PD), Italy
P. Mereu
INFN-Torino, Torino, Italy

The ESS Normal Conducting (NC) linac is composed of an ion source, a Low Energy Beam Transport line, a Radio Frequency Quarupole (RFQ), a Medium Energy Beam Transport Line (MEBT) and a Drift Tube Linac (DTL). It creates, bunches and accelerates the proton beam up to 90 MeV before injecting into the superconducting linac which will deliver a 5 MW beam onto the neutron production target. The construction of the NC linac is part of a broad collaboration involving experts of various Labs in Europe. The technical chalenges and the collaboration strategy for the NC linac will be presented.

THPP086

ESS DTL Error Study

1047

M. Comunian, F. Grespan, A. Pisent
INFN/LNL, Legnaro (PD), Italy

The Drift Tube Linac (DTL) of the European Spallation Source (ESS) is designed to operate at 352.2 MHz with a duty cycle of 4% (3 ms pulse length, 14 Hz repetition period) and will accelerate a proton beam of 62.5 mA pulse peak current from 3.62 to 90 MeV. The error study is decisive to define the DTL manufacturing tolerances and to evaluate its robustness. In this paper the DTL performances are shown.

THPP087

ESS DTL Design and Drift Tube Prototypes

1050

F. Grespan, M. Comunian, A. Pisent, M. Poggi, C. R. Roncolato
INFN/LNL, Legnaro (PD), Italy
P. Mereu
INFN-Torino, Torino, Italy

The Drift Tube Linac (DTL) for the ESS accelerator will accelerate protons up to 62.5 mA average pulse current from 3.62 to 90 MeV. The 5 tanks composing the DTL are designed to operate at 352.2 MHz in pulses of 2.86 ms long with a repetition rate of 14 Hz. The accelerating field is around 3.1 MV/m, constant in each tank. Permanent magnet quadrupoles (PMQs) are used as focusing element in a FODO lattice. The empty drift tubes accommodate Electro Magnetic Dipoles (EMDs) and Beam Position Monitors (BPMs) in order to implement beam corrective schemes. A complete set of Drift Tubes is under construction that is BPM, EMD and PMQ types. These prototypes are aimed to validate the design with the involved integration issues of the various components, as well as the overall technological and assembly process. This paper presents the main mechanical choices and the status of the prototyping program of the Drift Tubes.