Renzo Parodi - Academia.edu (original) (raw)
Papers by Renzo Parodi
The main activities of the Genoa Group are endowed by INFN under the ENEA-INFN joint Project for ... more The main activities of the Genoa Group are endowed by INFN under the ENEA-INFN joint Project for the development of the prototype components for an Accelerator Driven System for Nuclear Waste Transmutation. (TRASCO project) The Genoa Group (jointly with the INFN_Milan Group) works on the development of the Prototype structure of the High-Energy section of the linac (proton beta ranging from ~0.5 to ~ 0.85). The results achieved in the 2001 on that projects are quite encouraging; a “Linac Ready”5 cell sputtered cavity (beta 0.8, built and tested at CERN in 2000) was tested in a machine ready configuration. At the side of the Trasco Project the group is working to the development of a detection system for small Displacements (10 -20 cm) using two coupled superconducting cavities. (PACO Project) The method was proven successful achieving a sensitivity 10 -20 with a prototype cavity working at 3 GHz. This new detector is now the basis for the design of a two spherical cavity resonator t...
In this paper we present the project of the Solenoid Magnet for the PANDA detector developed in G... more In this paper we present the project of the Solenoid Magnet for the PANDA detector developed in Genova. This project features a coil realized with a Rutherford--type, aluminum stabilized superconducting cable, wound inside an aluminum alloy coil former and indirectly cooled with a forced circulation of liquid helium. The concept of this magnet is based on many other working magnets, developed for different detectors, such as BaBar, Finuda, Delphi or CMS. A complete characterization of the magnetic, mechanical and thermal properties of the magnet is presented, with an ansatz on the time schedule to be followed to fulfill the detector deadlines.
Multipacting (MP) is a resonant electron discharge, often plaguing radiofrequency structures, pro... more Multipacting (MP) is a resonant electron discharge, often plaguing radiofrequency structures, produced by the synchronization of emitted electrons with the RF fields and by the electron multiplication at the impact point with the surface of the structure. The current of re-emitted electrons grows via true secondary re-emission when the secondary yield for the primary electron impact energy is greater than one. A simple example (MP in short-gap accelerating axial-symmetric cavities) allows an analytical solution of the equation of motion, giving both the synchronization (kinematics) and multiplication (impact energy) conditions as a function of the gap voltage (or accelerating field). Starting from this example a thorough discussion of MP discharges in axial-symmetric accelerating structures will be given and some poor man's rules are given to estimate the critical cavity field levels to meet the kinematic condition for resonance. The results of these poor man's rules are com...
An overview of DAFNE, the Frascati Phi-factory project is presented. The DAFNE project has been a... more An overview of DAFNE, the Frascati Phi-factory project is presented. The DAFNE project has been approved and fully funded by the INFN Board of Directors in June 1990. The end of construction is scheduledfor December 1995.The short-term luminosity goal is 1.3x10^32 cm-2sec-1, while the ultimate luminosity target is 10^33 cm-2sec-1. All critical components of the project, injector, vacuum system, RF and feedback are dimensioned to cope with the target luminosity.
The Journal of Physical Chemistry C, 2012
The DAFNE Phi-factory complex of the INFN Frascati National Laboratory consists of two 510 MeV st... more The DAFNE Phi-factory complex of the INFN Frascati National Laboratory consists of two 510 MeV storage rings and an injector for toppingup. The project has been approved by the INFN Board of Directors in June 1990 and the engineering design has started in January 1991. The construction budget is 92 GLit (no salary and conventional constructions) and the commissioningnof the main rings is scheduled at the end of 1995. The general layout of the complex, which will be housed in the existing LNF buildings, is shown in Fig. 1. In the storage rings, electrons and positrons circulate in opposite directions, intersecting at two interaction points. The first interaction region is dedicated to a large detector KLOE [1] forCP violation experiments. A letter of intent has been submitted to use the second interaction region for nuclear physics experiments, with a smaller size detector. The short term luminosity goal is 1.3 10^32 cm-2s -1 while the ultimate target is -10^33 cm-2s -1.
The main activities of the Genoa Group are endowed by INFN under the “Special project on RF Super... more The main activities of the Genoa Group are endowed by INFN under the “Special project on RF Superconductivity” grant. The main goal of the project is the development of new techniques and new materials for Superconducting RF accelerators. The research aims are mainly to give a contribution to the next generation of TeV linear collider either by reducing the production cost of the resonators or reducing the cryogenic plant‘s installation and running costs. The Genoa Group works mainly to check the effectiveness of the Niobium based Nitrides for accelerator application. As a side investigation the Group works, in collaboration with LAL Orsay, to understand the reasons for the limitations on the surface field. This investigation is performed by tacking advantage of the NEPAL installation in ORSAY. The group is starting to work to the joint R&D project of INFN and ENEA aiming to check the feasibility of a high current superconducting proton accelerator as a driver of a neutron source. N...
A superconducting cavity ready for the installation in a particle accelerator need to be equipped... more A superconducting cavity ready for the installation in a particle accelerator need to be equipped with a quite complex suite of ancillary devices often as complex and challenging as the cavity itself. Fundamental power coupler(s) (used to feed power to the accelerating beam) and HOM couplers (used to extract the idle RF power left from the circulating beam on the cavity modes different from the accelerating one) are examples of that kind of devices. Tuners (used to keep the frequency and phase of the cavity locked to the master oscillator used as a pace maker for the beam bunches) are a further category of ancillaries. All types, if not properly designed and built, will probably degrade the cavity performance beyond any possibility of easy recover. The lecture will introduce the different implementation of couplers and tuners and the related design constraints. This last part of the design accounts for about the remaining 40% of the design task and accounts for the Main Couplers, the Cavity Tuners and the High Order Mode (HOM) dampers.
Niobium surface has been studied for more than 20 years and most of these studies have been drive... more Niobium surface has been studied for more than 20 years and most of these studies have been driven by the demands of high performance SC cavities. Experience has shown that such performances depend critically on the surface treatment applied, be it mechanical, thermal, chemical or any combination of these. The aim of this work is to look whether there is a significant connection among the XPS data acquired on differently treated samples and the cavity performances. To do this, we extract the information out of the spectras using mathematical and statistical concepts rather than chemical knowledge. If this prooves successful, we could use the XPS as a very efficient and inexpensive tool to determine the most suitable surface treatment for the next generation SC cavities.
IEEE Transactions on Nuclear Science
Abstracz: This paper deals with the design of high 0 TE resonators for high efficiency RF pulse c... more Abstracz: This paper deals with the design of high 0 TE resonators for high efficiency RF pulse compression. This kind of resonator 1s used to double the energy gradient of linear accelerators. In order to study the influence of the geomet:-y of the resonator on the Q , a computer code nemed OSCAR2D was developed. By means of this code ar, optimum geometry for TE storage cavfties was found. The results of the computer simulation are shortly compared with the experimental measurements performed on a TE caiilty prototype.
IEEE Transactions on Magnetics
ABSTRACT
Journal of Applied Physics
Page 1. Study of niobium nitrides for superconducting rf cavities P. Fabbricatore, P.Fernandes,3»... more Page 1. Study of niobium nitrides for superconducting rf cavities P. Fabbricatore, P.Fernandes,3» G, С. ... The cavity from which we started, de-scribed in the section "rf measurements," has walls 0.1 cm thick with large niobium grains (0.3-0.5 cm) visible on the surface. ...
Journal of Superconductivity
ABSTRACT
The main activities of the Genoa Group are endowed by INFN under the ENEA-INFN joint Project for ... more The main activities of the Genoa Group are endowed by INFN under the ENEA-INFN joint Project for the development of the prototype components for an Accelerator Driven System for Nuclear Waste Transmutation. (TRASCO project) The Genoa Group (jointly with the INFN_Milan Group) works on the development of the Prototype structure of the High-Energy section of the linac (proton beta ranging from ~0.5 to ~ 0.85). The results achieved in the 2001 on that projects are quite encouraging; a “Linac Ready”5 cell sputtered cavity (beta 0.8, built and tested at CERN in 2000) was tested in a machine ready configuration. At the side of the Trasco Project the group is working to the development of a detection system for small Displacements (10 -20 cm) using two coupled superconducting cavities. (PACO Project) The method was proven successful achieving a sensitivity 10 -20 with a prototype cavity working at 3 GHz. This new detector is now the basis for the design of a two spherical cavity resonator t...
In this paper we present the project of the Solenoid Magnet for the PANDA detector developed in G... more In this paper we present the project of the Solenoid Magnet for the PANDA detector developed in Genova. This project features a coil realized with a Rutherford--type, aluminum stabilized superconducting cable, wound inside an aluminum alloy coil former and indirectly cooled with a forced circulation of liquid helium. The concept of this magnet is based on many other working magnets, developed for different detectors, such as BaBar, Finuda, Delphi or CMS. A complete characterization of the magnetic, mechanical and thermal properties of the magnet is presented, with an ansatz on the time schedule to be followed to fulfill the detector deadlines.
Multipacting (MP) is a resonant electron discharge, often plaguing radiofrequency structures, pro... more Multipacting (MP) is a resonant electron discharge, often plaguing radiofrequency structures, produced by the synchronization of emitted electrons with the RF fields and by the electron multiplication at the impact point with the surface of the structure. The current of re-emitted electrons grows via true secondary re-emission when the secondary yield for the primary electron impact energy is greater than one. A simple example (MP in short-gap accelerating axial-symmetric cavities) allows an analytical solution of the equation of motion, giving both the synchronization (kinematics) and multiplication (impact energy) conditions as a function of the gap voltage (or accelerating field). Starting from this example a thorough discussion of MP discharges in axial-symmetric accelerating structures will be given and some poor man's rules are given to estimate the critical cavity field levels to meet the kinematic condition for resonance. The results of these poor man's rules are com...
An overview of DAFNE, the Frascati Phi-factory project is presented. The DAFNE project has been a... more An overview of DAFNE, the Frascati Phi-factory project is presented. The DAFNE project has been approved and fully funded by the INFN Board of Directors in June 1990. The end of construction is scheduledfor December 1995.The short-term luminosity goal is 1.3x10^32 cm-2sec-1, while the ultimate luminosity target is 10^33 cm-2sec-1. All critical components of the project, injector, vacuum system, RF and feedback are dimensioned to cope with the target luminosity.
The Journal of Physical Chemistry C, 2012
The DAFNE Phi-factory complex of the INFN Frascati National Laboratory consists of two 510 MeV st... more The DAFNE Phi-factory complex of the INFN Frascati National Laboratory consists of two 510 MeV storage rings and an injector for toppingup. The project has been approved by the INFN Board of Directors in June 1990 and the engineering design has started in January 1991. The construction budget is 92 GLit (no salary and conventional constructions) and the commissioningnof the main rings is scheduled at the end of 1995. The general layout of the complex, which will be housed in the existing LNF buildings, is shown in Fig. 1. In the storage rings, electrons and positrons circulate in opposite directions, intersecting at two interaction points. The first interaction region is dedicated to a large detector KLOE [1] forCP violation experiments. A letter of intent has been submitted to use the second interaction region for nuclear physics experiments, with a smaller size detector. The short term luminosity goal is 1.3 10^32 cm-2s -1 while the ultimate target is -10^33 cm-2s -1.
The main activities of the Genoa Group are endowed by INFN under the “Special project on RF Super... more The main activities of the Genoa Group are endowed by INFN under the “Special project on RF Superconductivity” grant. The main goal of the project is the development of new techniques and new materials for Superconducting RF accelerators. The research aims are mainly to give a contribution to the next generation of TeV linear collider either by reducing the production cost of the resonators or reducing the cryogenic plant‘s installation and running costs. The Genoa Group works mainly to check the effectiveness of the Niobium based Nitrides for accelerator application. As a side investigation the Group works, in collaboration with LAL Orsay, to understand the reasons for the limitations on the surface field. This investigation is performed by tacking advantage of the NEPAL installation in ORSAY. The group is starting to work to the joint R&D project of INFN and ENEA aiming to check the feasibility of a high current superconducting proton accelerator as a driver of a neutron source. N...
A superconducting cavity ready for the installation in a particle accelerator need to be equipped... more A superconducting cavity ready for the installation in a particle accelerator need to be equipped with a quite complex suite of ancillary devices often as complex and challenging as the cavity itself. Fundamental power coupler(s) (used to feed power to the accelerating beam) and HOM couplers (used to extract the idle RF power left from the circulating beam on the cavity modes different from the accelerating one) are examples of that kind of devices. Tuners (used to keep the frequency and phase of the cavity locked to the master oscillator used as a pace maker for the beam bunches) are a further category of ancillaries. All types, if not properly designed and built, will probably degrade the cavity performance beyond any possibility of easy recover. The lecture will introduce the different implementation of couplers and tuners and the related design constraints. This last part of the design accounts for about the remaining 40% of the design task and accounts for the Main Couplers, the Cavity Tuners and the High Order Mode (HOM) dampers.
Niobium surface has been studied for more than 20 years and most of these studies have been drive... more Niobium surface has been studied for more than 20 years and most of these studies have been driven by the demands of high performance SC cavities. Experience has shown that such performances depend critically on the surface treatment applied, be it mechanical, thermal, chemical or any combination of these. The aim of this work is to look whether there is a significant connection among the XPS data acquired on differently treated samples and the cavity performances. To do this, we extract the information out of the spectras using mathematical and statistical concepts rather than chemical knowledge. If this prooves successful, we could use the XPS as a very efficient and inexpensive tool to determine the most suitable surface treatment for the next generation SC cavities.
IEEE Transactions on Nuclear Science
Abstracz: This paper deals with the design of high 0 TE resonators for high efficiency RF pulse c... more Abstracz: This paper deals with the design of high 0 TE resonators for high efficiency RF pulse compression. This kind of resonator 1s used to double the energy gradient of linear accelerators. In order to study the influence of the geomet:-y of the resonator on the Q , a computer code nemed OSCAR2D was developed. By means of this code ar, optimum geometry for TE storage cavfties was found. The results of the computer simulation are shortly compared with the experimental measurements performed on a TE caiilty prototype.
IEEE Transactions on Magnetics
ABSTRACT
Journal of Applied Physics
Page 1. Study of niobium nitrides for superconducting rf cavities P. Fabbricatore, P.Fernandes,3»... more Page 1. Study of niobium nitrides for superconducting rf cavities P. Fabbricatore, P.Fernandes,3» G, С. ... The cavity from which we started, de-scribed in the section "rf measurements," has walls 0.1 cm thick with large niobium grains (0.3-0.5 cm) visible on the surface. ...
Journal of Superconductivity
ABSTRACT