The ADIGE (Acceleratore Di Ioni a Grande carica Esotici) injector consists of an electrostatic 1+ beam line, equipped with ion sources able to produce a wide variety of beams, coupled to a magnetic beam line, where charge multiplication is accomplished by implementing an Electron Cyclotron Resonance (ECR) based charge breeder. The injector is totally integrated in the SPES (Selective Production of Exotic Species) beam line, to allow the post-acceleration of radioactive ions and is now in an advanced phase of installation. The electrostatic 1+beam line has been put into operation and is now producing beams from alkali metals. This contribution concerns the first results of the beam commissioning of this part of the injector, with the description of the initial debug phase and the solutions adopted to ensure a reliable and continuous operation. Preliminary results of the 1+ beam line characterization will be shown, with a comparison between simulated and measured emittances.
The ADIGE (Acceleratore Di Ioni a Grande carica Esotici) injector of the SPES (Selective Production of Exotic Species) project is now in an advanced phase of installation. Its main components have been designed following particular needs of the project: first, an Electron Cyclotron Resonance (ECR)-based Charge Breeder (SPES-CB), to boost the charge states of the radioactive ions produced at SPES and allow their post-acceleration. Then, a stable 1+ source and a complete electrostatic beam line to characterize the SPES-CB. Finally, a unique Medium Resolution Mass Spectrometer (MRMS, R=1/1000), mounted on a high voltage platform downstream the SPES-CB, to clean the radioactive beam from the contaminants induced by the breeding stage. This contribution describes the status of the injector, in particular the installation of the platform housing the MRMS, the access and safety system adopted and the first beams to be extracted from the stable 1+ source.
During 2018, the PIAVE superconducting linac injector at INFN-LNL, based on superconducting RFQs and two cryomodules with quarter wave resonators, underwent a renovation plan. This operation was strictly related to the one carried out on ALPI [1], which will become a post-accelerator for both stable and exotic beams in a near future. PIAVE Quarter Wave Resonator (QWR) cryomodules, in operation since 2006, were moved to ALPI to be used for the acceleration of both stable beams and future exotic beams delivered from the cyclotron target-ion-source station, after appropriate purification, charge breeding and pre-acceleration stages. In order to cope with the removal of the two QWR cryomodules in PIAVE, a newly designed 80 MHz room temperature buncher was designed, built and tested: the buncher is required so as to match the longitudinal phase space between PIAVE superconducting RFQs (SRFQ1 and SRFQ2) and ALPI. In the same period, substantial refurbishments on the ECR ion source platform were carried out, in particular on its infrastructure and safety equipment. A problem on an electronic component on SRFQ2, though quickly fixed, delayed beam commissioning of the PIAVE injector, which will start at the end of May 2019.
The ALPI linac at INFN-LNL was substantially refurbished in 2018, especially in view of its use as secondary accelerator for exotic species in the framework of the SPES project. In particular: 10 magnetic triplets were replaced with higher gradient ones; two cryomodules with quarter wave resonator were moved from the PIAVE injector to ALPI, so as to make them available both for exotic and stable beams; the cryogenic plant was renovated; the whole linac, its injector and its beam lines were eventually realigned via LASER tracking (LT). The expected outcome of the refurbishment project is a larger beam transmission (crucial for the efficient transport of the unavoidably low current exotic beams) and improved overall reliability so as to further extend the lifetime of an already 25 years old machine. The hardware commissioning of this new configuration will be reported.
Superconducting RFQs (SRFQs), the first SC RFQs ever made operational for users, have been operated on the PIAVE SC heavy ion linac injector at INFN-Legnaro since 2006. The structure is split into two resonators and is limited to the accelerating RFQ sections. The resonators had never exceeded 80% of the design accelerating fields. In 2015, an upgrade plan started, aimed at increasing the accelerating fields, while improving their slow and fast tuning systems, repairing degraded components, implementing a LASER alignment method. The upgrade plan was successfully concluded in summer 2017. The resonators were kept stably locked for days at a field larger than the nominal one. Eventually, a test beam was accelerated successfully for 72 hours, with negligible locking issues. SRFQs entered once again routine operation in December 2017. The new features will allow to accelerate heavy ions with an A/q value as high as 8.5 (versus a former maximum A/q=7.5), allowing operation of the very first accelerated uranium beams at INFN-LNL, after the related authorizations shall have been issued.
Since fall 2017, the ADIGE (Acceleratore Di Ioni a Grande carica Esotici) injector of the SPES (Selective Production of Exotic Species) project entered the installation phase. The injector includes an Electron Cyclotron Resonance (ECR)-based Charge Breeder (SPES-CB) and its complete beam line, as well as a newly designed RFQ, to allow the post-acceleration of the radioactive ions produced in the so-called target-ion source-system. The injector has different peculiarities, deriving from particular needs of SPES: a complete electrostatic beam line equipped with a 1+ source for test purposes, and a unique Medium Resolution Mass Spectrometer (MRMS, R similar to 1/1000), mounted downstream the SPES-CB, to clean the radioactive beam from the contaminants induced by the breeding stage. This contribution reports about the status of the installation of the injector, describing the various technical solution adopted, and giving a realistic planning for the commission and following operation of its main parts.
For the SPES project at Legnaro National Laboratories (LNL), a Low-Level Radio Frequency (LLRF) has been designed to have flexibility, reusability and an high precision. It is an FPGA-based digital feedback control systemusing RF ADCs for the direct undersampling and it can control at the same time eight different cavities. The LLRF system was tested on the field with an accelerated beam. In the last year some improvements on the firmware, software and hardware of the control system have been done. In this paper the results carried out in the more recent tests, the future works and the upgrades of the system will be detailed.