Marco Di Giacomo - Academia.edu (original) (raw)
Papers by Marco Di Giacomo
Nukleonika, 2003
In December 2001, a 5 kW beam was accelerated for the first time at GANIL. This performance was a... more In December 2001, a 5 kW beam was accelerated for the first time at GANIL. This performance was achieved after the increase of SSC2 dee voltage from 170 kV to 200 kV. Moreover, several technical developments have been done, to improve the operation with high intensity beams, and a new electrostatic deflector is under construction in order to reduce losses and activation at the exit of SSC2. This paper presents an overview of these works and the main results on the last accelerated beams.
HAL (Le Centre pour la Communication Scientifique Directe), Aug 28, 2022
The commissioning of SPIRAL2 was carried out in different steps and slots from 2014 to end 2021. ... more The commissioning of SPIRAL2 was carried out in different steps and slots from 2014 to end 2021. In a first phase, the proton-deuteron and heavy ion sources, LEBT lines and RFQ were commissioned and validated with A/Q=1 up to 3 particles. The validation of the MEBT (between the RFQ and the linac, including the Single Bunch Selector), linac and HEBT lines (up to the beam dump and to the NFS experimental room) started on July 2019, when GANIL received the authorization to operate SPIRAL2. The linac tuning is now validated with H + , 4 He 2+ and D + and nominal H + and D + beams were sent to NFS for physics experiments. The main results obtained during the commissioning stages and the strategy used by the commissioning team are presented.
HAL (Le Centre pour la Communication Scientifique Directe), Aug 28, 2022
Physical Review Accelerators and Beams
The SPIRAL2 injector includes a 5 mA proton-deuteron ECR source, a 1 mA ECR heavy ion source (up ... more The SPIRAL2 injector includes a 5 mA proton-deuteron ECR source, a 1 mA ECR heavy ion source (up to A/Q =3) and a CW 0.73 MeV/u RFQ. It has been successfully commissioned using a diagnostic-plate in parallel with the superconducting linac installation. The green light has been obtained for the LINAC commissioning in July of 2019, starting with the Medium Energy Beam Transport (MEBT) commissioning with protons then with helium in 2020. The MEBT line and tuning process are described. The main experimental results are given, including the emittance and profile measurements which are compared with TraceWin simulations. RFQ output energy variation has been found due to an input energy error, its correction optimizing the source platform voltage is presented.
The SPIRAL2 injector, made up of a 5 mA p-d ion source, a 1 mA heavy ion source (up to A/Q = 3) a... more The SPIRAL2 injector, made up of a 5 mA p-d ion source, a 1 mA heavy ion source (up to A/Q = 3) and a CW 0.75 MeV/u RFQ, has been commissioned in parallel with the superconducting linac installation. This com-missioning is successfully completed now and the Diag-nostic plate (D-plate) used to characterize the injector beams is removed. This paper presents the results ob-tained with the reference particles (H⁺, 4He2+, 18O6+ and 40Ar14+) and a comparison with the simulations. The connexion to the SC linac and the future linac beam commissioning is briefly described.
The SPIRAL2 project at GANIL is based on a superconducting ion continuous wave LINAC with two ass... more The SPIRAL2 project at GANIL is based on a superconducting ion continuous wave LINAC with two associated experimental areas named S3 (Super Separator Spectrometer) and NFS (Neutron For Science). This paper will report the main contributions of Mechanical Design Group at GANIL to the project. Mechanical engineers have been highly involved since 2005 from the pre-design of the accelerator and its development until present to finalize the installation. During the development phase, design and numerical simulation were used throughout the complete process: from the ion sources, to the LINAC accelerator, then through beam transport lines to experimental halls equipped with detectors. The entire installation (process, buildings and systems) is integrated in 3D CAD models. The paper focuses on three equipments designed in collaboration with electronics engineers and physicists : the Rebuncher in Mean Energy Beam Transport line; the Instrumentation Profiler SEM and the Target Chamber in S3....
SNRC and CEA collaborate to the upgrade of the SARAF Accelerator to 5 mA CW 40 MeV deuteron and p... more SNRC and CEA collaborate to the upgrade of the SARAF Accelerator to 5 mA CW 40 MeV deuteron and proton beams (Phase 2). This paper presents the reference design of the SARAF-LINAC Project including a four-vane 176 MHz RFQ, a MEBT and a superconducting linac made of four five-meter cryomodules housing 26 superconducting HWR cavities and 20 superconducting solenoids. The first two identical cryomodules house low-beta (βopt = 0.091), 280 mm long (flange to flange), 176 MHz HWR cavities, the two identical last cryomodules house high-beta (βopt = 0.181), 410 mm long, 176 MHz, HWR cavities. The beam is focused with superconducting solenoids located between cavities housing steering coils. A BPM is placed upstream each solenoid.
The SPIRAL2 RFQ was recently successfully commissioned at nominal voltage of 114 kV, correspondin... more The SPIRAL2 RFQ was recently successfully commissioned at nominal voltage of 114 kV, corresponding to 1.65 Kilpatrick factor. The paper describes limitations of the RFQ main subsystems, cavity conditioning difficulties, as well as changes implemented in the LLRF and automatic procedures to simplify turn on and operation of the whole system. INTRODUCTION The SPIRAL2 RFQ [1] is driven with four independent RF chains directly combined into the cavity. Cavity loss was estimated around 160-180 kW at highest operating voltage (~114 kV) and four 60 kW RF power chains were chosen to preserve the quadrant symmetry and to lead to realistic specifications for the circulators and amplifiers. Figure 1: RFQ RF system. The RFQ RF system is shown in Fig. 1. The LLRF defines the master/slave configuration chosen to synchronise the four chains. Master LLRF controls the amplitude and phase stability, while slave LLRF follow the incident power of the master chain. Master LLRF also measures the cavity d...
Three normal conducting rebunchers will be installed at the Medium Energy Beam Transport (MEBT) o... more Three normal conducting rebunchers will be installed at the Medium Energy Beam Transport (MEBT) of the SARAF-LINAC phase II [saraf]. The MEBT line is designed to follow a 1.3 MeV/u RFQ, is about 5 m long, and contains three 176 MHz rebunchers providing a field integral of 10⁵ kV. CEA is in charge of the design and fabrication of the Cu plated stainless steel, 3-gap rebuncher. The high power tests and RF conditioning have been successfully performed at the CEA Saclay on the first cavity. A solid state power amplifier, which has been developed by SNRC and has been used for the RF tests. The cavity has shown a good performance according to calculations, regarding the dissipated power, peak temperatures and coupling factor. RF conditioning was started with a duty cycle of 1\% and increased gradually until continuous wave (CW), which is the nominal working mode in SARAF-LINAC.
SNRC and CEA collaborate to the upgrade of the SARAF accelerator to 5 mA CW 40 MeV deuteron and p... more SNRC and CEA collaborate to the upgrade of the SARAF accelerator to 5 mA CW 40 MeV deuteron and proton beams (Phase 2). CEA is in charge of the design, construction and commissioning of the MEBT line and the superconducting linac (SARAF-LINAC Project). The prototypes of the 176 MHz NC rebuncher, SC cavities, RF coupler and SC Solenoid-Package are under construction and their test stands construction or adaptation is in progress at Saclay. Meanwhile, the cryomodules and the global system just passed their Critical Design Reviews. This paper presents the status of the SARAF-LINAC Project at April 2018. INTRODUCTION The SARAF-LINAC project, managed by CEA (France), integrated to the SARAF-Phase 2 project managed by SNRC (Israel) has been introduced in [1]. In 2014, a first System Design Report was presented and served of basis on an agreement between CEA and SNRC. The < 8 year project can be simplified in 3 overlapping phases (Fig. 1): ~3 years of detailed design, including protot...
The SPIRAL2 beam commissioning has started and the superconducting linac installation is being fi... more The SPIRAL2 beam commissioning has started and the superconducting linac installation is being finalized. The conditioning of the Radio Frequency Quadrupole (RFQ) [1] begun in 2015, and the beam commissioning soon after. Among the beam parameters checked at the RFQ output, the energy, bunch length and longitudinal emittance have been measured for the 3 referenced particles.
The SPIRAL2 88 MHz CW RFQ is designed to accelerate light and heavy ions with A/Q from 1 to 3 at ... more The SPIRAL2 88 MHz CW RFQ is designed to accelerate light and heavy ions with A/Q from 1 to 3 at 0.73 MeV/A. The nominal beam intensities are up to 5 mA CW for both proton and deuteron beams and up to 1 mA CW for heavier ions. The design foresees almost 100% transmission for all ions at nominal beam current and emittance. Beam commissioning of the RFQ and linac cool down started already. The specifications have been achieved within the measurement precision for the different ions accelerated yet. This paper describes the beam commissioning strategy, the measurement results in both transverse and longitudinal planes and the success-fully first cryogenic tests of the linac.
The Spiral2 SC linac uses solid state amplifiers ranging from 2.5 to 19 kW and external circulato... more The Spiral2 SC linac uses solid state amplifiers ranging from 2.5 to 19 kW and external circulators to drive normal and superconducting cavities working at 88.0525 MHz. The project has no manpower for in house development and all power devices are ordered to commercial companies. Robust acceptance tests have then been defined to check reliability with respect to our application. The papers describes the tests procedure and results on our first units.
The conceptual design of a linear SC accelerator, LINAG, was started a few months ago to satisfy ... more The conceptual design of a linear SC accelerator, LINAG, was started a few months ago to satisfy a request for high intensity deuteron and ion beams for the shortand long-term developments in the study of nuclei far from stability at GANIL. LINAGs first step, LINAG 1, will accelerate ions with m/q = 3 up to 14.5 MeV/u (1 mA max.) and D up to 20 MeV/u, 5 mA max., which corresponds to a beam power of 200 kW. With the use of the D beam on a uranium target, our second-generation facility for Rare Ion Beams (RIB), SPIRAL II, will add medium-mass nuclei to those available at present. In the longer term, the machine should evolve towards a heavy ion driver, in the energy domain of 100 MeV/u, able to accelerate m/q = 3 to 6 (low to medium-mass nuclei) with a maximum beam power of 300 kW, in order to upgrade the GANIL facility for the production of secondary beams. The paper presents the preliminary choices and the points still under discussion of the LINAG 1 design.
SNRC and CEA collaborate to the upgrade of the SARAF accelerator to 5 mA CW 40 MeV deuteron and p... more SNRC and CEA collaborate to the upgrade of the SARAF accelerator to 5 mA CW 40 MeV deuteron and proton beams (Phase 2). CEA is in charge of the design, construction and commissioning of the superconducting linac (SARAF-LINAC Project). This paper presents to the accelerator community the status at March 2016 of the SARAF-LINAC Project. INTRODUCTION The SARAF-LINAC project, managed by CEA (France), integrated to the SARAF-Phase 2 project managed by SNRC (Israel) has been introduced in [1]. In 2014, a first System Design Report (on the base of which [1] was written) was presented and served of basis on an agreement between CEA and SNRC. The < 8 year project can be simplified in 3 overlapping phases (Fig. 1): ~3 years of detailed design, including prototyping, ~4 years of construction, assembly and test at Saclay, ~2 years of installation and commissioning at Soreq. January 2016: for system. In this paper, the status of these developments after the first year of detailed desi...
The SPIRAL2 RFQ is designed to accelerate light and heavy ions with A/Q from 1 to 3 at 0.73 MeV/A... more The SPIRAL2 RFQ is designed to accelerate light and heavy ions with A/Q from 1 to 3 at 0.73 MeV/A. The nominal beam intensities are up to 5 mA CW for both proton and deuteron beams and up to 1 mA CW for heavier ions. The four-vane cavity is made with 5 1-meter long sections mechanically assembled, it works at 88 MHz and is powered up to 180 kW CW to achieve the nominal vane voltage of 113.7 kV for A/Q = 3 ions. This paper describes the RF conditioning of the RFQ at GANIL with the setting of its RF systems and cooling system used to tune the cavity resonance frequency.
The SPIRAL2 project beam commissioning is started and the superconducting linac installation is b... more The SPIRAL2 project beam commissioning is started and the superconducting linac installation is being finalized. In parallel with the installations, the first proton beam was extracted in 2014 and the expected beam performances were achieved from both light and heavy ion sources. The conditioning of the RFQ started in October 2015, and the beam commissioning soon after that. After having briefly recalled the project scope and parameters, the present situation of the RFQ beam commissioning is presented.
Nukleonika, 2003
In December 2001, a 5 kW beam was accelerated for the first time at GANIL. This performance was a... more In December 2001, a 5 kW beam was accelerated for the first time at GANIL. This performance was achieved after the increase of SSC2 dee voltage from 170 kV to 200 kV. Moreover, several technical developments have been done, to improve the operation with high intensity beams, and a new electrostatic deflector is under construction in order to reduce losses and activation at the exit of SSC2. This paper presents an overview of these works and the main results on the last accelerated beams.
HAL (Le Centre pour la Communication Scientifique Directe), Aug 28, 2022
The commissioning of SPIRAL2 was carried out in different steps and slots from 2014 to end 2021. ... more The commissioning of SPIRAL2 was carried out in different steps and slots from 2014 to end 2021. In a first phase, the proton-deuteron and heavy ion sources, LEBT lines and RFQ were commissioned and validated with A/Q=1 up to 3 particles. The validation of the MEBT (between the RFQ and the linac, including the Single Bunch Selector), linac and HEBT lines (up to the beam dump and to the NFS experimental room) started on July 2019, when GANIL received the authorization to operate SPIRAL2. The linac tuning is now validated with H + , 4 He 2+ and D + and nominal H + and D + beams were sent to NFS for physics experiments. The main results obtained during the commissioning stages and the strategy used by the commissioning team are presented.
HAL (Le Centre pour la Communication Scientifique Directe), Aug 28, 2022
Physical Review Accelerators and Beams
The SPIRAL2 injector includes a 5 mA proton-deuteron ECR source, a 1 mA ECR heavy ion source (up ... more The SPIRAL2 injector includes a 5 mA proton-deuteron ECR source, a 1 mA ECR heavy ion source (up to A/Q =3) and a CW 0.73 MeV/u RFQ. It has been successfully commissioned using a diagnostic-plate in parallel with the superconducting linac installation. The green light has been obtained for the LINAC commissioning in July of 2019, starting with the Medium Energy Beam Transport (MEBT) commissioning with protons then with helium in 2020. The MEBT line and tuning process are described. The main experimental results are given, including the emittance and profile measurements which are compared with TraceWin simulations. RFQ output energy variation has been found due to an input energy error, its correction optimizing the source platform voltage is presented.
The SPIRAL2 injector, made up of a 5 mA p-d ion source, a 1 mA heavy ion source (up to A/Q = 3) a... more The SPIRAL2 injector, made up of a 5 mA p-d ion source, a 1 mA heavy ion source (up to A/Q = 3) and a CW 0.75 MeV/u RFQ, has been commissioned in parallel with the superconducting linac installation. This com-missioning is successfully completed now and the Diag-nostic plate (D-plate) used to characterize the injector beams is removed. This paper presents the results ob-tained with the reference particles (H⁺, 4He2+, 18O6+ and 40Ar14+) and a comparison with the simulations. The connexion to the SC linac and the future linac beam commissioning is briefly described.
The SPIRAL2 project at GANIL is based on a superconducting ion continuous wave LINAC with two ass... more The SPIRAL2 project at GANIL is based on a superconducting ion continuous wave LINAC with two associated experimental areas named S3 (Super Separator Spectrometer) and NFS (Neutron For Science). This paper will report the main contributions of Mechanical Design Group at GANIL to the project. Mechanical engineers have been highly involved since 2005 from the pre-design of the accelerator and its development until present to finalize the installation. During the development phase, design and numerical simulation were used throughout the complete process: from the ion sources, to the LINAC accelerator, then through beam transport lines to experimental halls equipped with detectors. The entire installation (process, buildings and systems) is integrated in 3D CAD models. The paper focuses on three equipments designed in collaboration with electronics engineers and physicists : the Rebuncher in Mean Energy Beam Transport line; the Instrumentation Profiler SEM and the Target Chamber in S3....
SNRC and CEA collaborate to the upgrade of the SARAF Accelerator to 5 mA CW 40 MeV deuteron and p... more SNRC and CEA collaborate to the upgrade of the SARAF Accelerator to 5 mA CW 40 MeV deuteron and proton beams (Phase 2). This paper presents the reference design of the SARAF-LINAC Project including a four-vane 176 MHz RFQ, a MEBT and a superconducting linac made of four five-meter cryomodules housing 26 superconducting HWR cavities and 20 superconducting solenoids. The first two identical cryomodules house low-beta (βopt = 0.091), 280 mm long (flange to flange), 176 MHz HWR cavities, the two identical last cryomodules house high-beta (βopt = 0.181), 410 mm long, 176 MHz, HWR cavities. The beam is focused with superconducting solenoids located between cavities housing steering coils. A BPM is placed upstream each solenoid.
The SPIRAL2 RFQ was recently successfully commissioned at nominal voltage of 114 kV, correspondin... more The SPIRAL2 RFQ was recently successfully commissioned at nominal voltage of 114 kV, corresponding to 1.65 Kilpatrick factor. The paper describes limitations of the RFQ main subsystems, cavity conditioning difficulties, as well as changes implemented in the LLRF and automatic procedures to simplify turn on and operation of the whole system. INTRODUCTION The SPIRAL2 RFQ [1] is driven with four independent RF chains directly combined into the cavity. Cavity loss was estimated around 160-180 kW at highest operating voltage (~114 kV) and four 60 kW RF power chains were chosen to preserve the quadrant symmetry and to lead to realistic specifications for the circulators and amplifiers. Figure 1: RFQ RF system. The RFQ RF system is shown in Fig. 1. The LLRF defines the master/slave configuration chosen to synchronise the four chains. Master LLRF controls the amplitude and phase stability, while slave LLRF follow the incident power of the master chain. Master LLRF also measures the cavity d...
Three normal conducting rebunchers will be installed at the Medium Energy Beam Transport (MEBT) o... more Three normal conducting rebunchers will be installed at the Medium Energy Beam Transport (MEBT) of the SARAF-LINAC phase II [saraf]. The MEBT line is designed to follow a 1.3 MeV/u RFQ, is about 5 m long, and contains three 176 MHz rebunchers providing a field integral of 10⁵ kV. CEA is in charge of the design and fabrication of the Cu plated stainless steel, 3-gap rebuncher. The high power tests and RF conditioning have been successfully performed at the CEA Saclay on the first cavity. A solid state power amplifier, which has been developed by SNRC and has been used for the RF tests. The cavity has shown a good performance according to calculations, regarding the dissipated power, peak temperatures and coupling factor. RF conditioning was started with a duty cycle of 1\% and increased gradually until continuous wave (CW), which is the nominal working mode in SARAF-LINAC.
SNRC and CEA collaborate to the upgrade of the SARAF accelerator to 5 mA CW 40 MeV deuteron and p... more SNRC and CEA collaborate to the upgrade of the SARAF accelerator to 5 mA CW 40 MeV deuteron and proton beams (Phase 2). CEA is in charge of the design, construction and commissioning of the MEBT line and the superconducting linac (SARAF-LINAC Project). The prototypes of the 176 MHz NC rebuncher, SC cavities, RF coupler and SC Solenoid-Package are under construction and their test stands construction or adaptation is in progress at Saclay. Meanwhile, the cryomodules and the global system just passed their Critical Design Reviews. This paper presents the status of the SARAF-LINAC Project at April 2018. INTRODUCTION The SARAF-LINAC project, managed by CEA (France), integrated to the SARAF-Phase 2 project managed by SNRC (Israel) has been introduced in [1]. In 2014, a first System Design Report was presented and served of basis on an agreement between CEA and SNRC. The < 8 year project can be simplified in 3 overlapping phases (Fig. 1): ~3 years of detailed design, including protot...
The SPIRAL2 beam commissioning has started and the superconducting linac installation is being fi... more The SPIRAL2 beam commissioning has started and the superconducting linac installation is being finalized. The conditioning of the Radio Frequency Quadrupole (RFQ) [1] begun in 2015, and the beam commissioning soon after. Among the beam parameters checked at the RFQ output, the energy, bunch length and longitudinal emittance have been measured for the 3 referenced particles.
The SPIRAL2 88 MHz CW RFQ is designed to accelerate light and heavy ions with A/Q from 1 to 3 at ... more The SPIRAL2 88 MHz CW RFQ is designed to accelerate light and heavy ions with A/Q from 1 to 3 at 0.73 MeV/A. The nominal beam intensities are up to 5 mA CW for both proton and deuteron beams and up to 1 mA CW for heavier ions. The design foresees almost 100% transmission for all ions at nominal beam current and emittance. Beam commissioning of the RFQ and linac cool down started already. The specifications have been achieved within the measurement precision for the different ions accelerated yet. This paper describes the beam commissioning strategy, the measurement results in both transverse and longitudinal planes and the success-fully first cryogenic tests of the linac.
The Spiral2 SC linac uses solid state amplifiers ranging from 2.5 to 19 kW and external circulato... more The Spiral2 SC linac uses solid state amplifiers ranging from 2.5 to 19 kW and external circulators to drive normal and superconducting cavities working at 88.0525 MHz. The project has no manpower for in house development and all power devices are ordered to commercial companies. Robust acceptance tests have then been defined to check reliability with respect to our application. The papers describes the tests procedure and results on our first units.
The conceptual design of a linear SC accelerator, LINAG, was started a few months ago to satisfy ... more The conceptual design of a linear SC accelerator, LINAG, was started a few months ago to satisfy a request for high intensity deuteron and ion beams for the shortand long-term developments in the study of nuclei far from stability at GANIL. LINAGs first step, LINAG 1, will accelerate ions with m/q = 3 up to 14.5 MeV/u (1 mA max.) and D up to 20 MeV/u, 5 mA max., which corresponds to a beam power of 200 kW. With the use of the D beam on a uranium target, our second-generation facility for Rare Ion Beams (RIB), SPIRAL II, will add medium-mass nuclei to those available at present. In the longer term, the machine should evolve towards a heavy ion driver, in the energy domain of 100 MeV/u, able to accelerate m/q = 3 to 6 (low to medium-mass nuclei) with a maximum beam power of 300 kW, in order to upgrade the GANIL facility for the production of secondary beams. The paper presents the preliminary choices and the points still under discussion of the LINAG 1 design.
SNRC and CEA collaborate to the upgrade of the SARAF accelerator to 5 mA CW 40 MeV deuteron and p... more SNRC and CEA collaborate to the upgrade of the SARAF accelerator to 5 mA CW 40 MeV deuteron and proton beams (Phase 2). CEA is in charge of the design, construction and commissioning of the superconducting linac (SARAF-LINAC Project). This paper presents to the accelerator community the status at March 2016 of the SARAF-LINAC Project. INTRODUCTION The SARAF-LINAC project, managed by CEA (France), integrated to the SARAF-Phase 2 project managed by SNRC (Israel) has been introduced in [1]. In 2014, a first System Design Report (on the base of which [1] was written) was presented and served of basis on an agreement between CEA and SNRC. The < 8 year project can be simplified in 3 overlapping phases (Fig. 1): ~3 years of detailed design, including prototyping, ~4 years of construction, assembly and test at Saclay, ~2 years of installation and commissioning at Soreq. January 2016: for system. In this paper, the status of these developments after the first year of detailed desi...
The SPIRAL2 RFQ is designed to accelerate light and heavy ions with A/Q from 1 to 3 at 0.73 MeV/A... more The SPIRAL2 RFQ is designed to accelerate light and heavy ions with A/Q from 1 to 3 at 0.73 MeV/A. The nominal beam intensities are up to 5 mA CW for both proton and deuteron beams and up to 1 mA CW for heavier ions. The four-vane cavity is made with 5 1-meter long sections mechanically assembled, it works at 88 MHz and is powered up to 180 kW CW to achieve the nominal vane voltage of 113.7 kV for A/Q = 3 ions. This paper describes the RF conditioning of the RFQ at GANIL with the setting of its RF systems and cooling system used to tune the cavity resonance frequency.
The SPIRAL2 project beam commissioning is started and the superconducting linac installation is b... more The SPIRAL2 project beam commissioning is started and the superconducting linac installation is being finalized. In parallel with the installations, the first proton beam was extracted in 2014 and the expected beam performances were achieved from both light and heavy ion sources. The conditioning of the RFQ started in October 2015, and the beam commissioning soon after that. After having briefly recalled the project scope and parameters, the present situation of the RFQ beam commissioning is presented.