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A new RF photo-injector has been designed, realized and successfully installed at the SPARC_LAB facility (INFN-LNF, Frascati, Rome). It is based on a 1.6 cell RF gun fabricated with the new brazing free technology recently developed at the National Laboratories of Frascati. The electromagnetic design has been optimized to have a full compensation of the dipole and quadrupole field components introduced by the coupling hole with an improvement of the effective pumping speed with two added pumping ports. The gun is overcoupled (\beta=2) to reduce the filling time and to allow the operation with short RF pulses. The overall injector integrates a new solenoid with a remote control of the transverse position and a variable skew quadrupole for the compensation of residual quadrupole field components. It also allows an on axis laser injection system with the last mirror in air, and the possibility of a future integration of an X/C band cavity linearizer. In the paper we report the main characteristics of the electromagnetic and mechanical design and the low and high power test results that shows the extremely good perfomances of the new device., Proceedings of the 13th International Particle Accelerator Conference, IPAC2022, Bangkok, Thailand

In 2021 started the commissioning of the TEX (Test stand for X-band) facility at the Frascati National laboratories of INFN. This facility has been founded in the framework of the LATINO (Laboratory in Advanced Technologies for INnOvation) project. The current facility layout includes an high power X-band (11.994 GHz) RF source, realized in collaboration with CERN, which will be used for validation and development of the X-band RF high gradient technology in view of the EuPRAXIA@SPARC_LAB project. The RF source is based on a CPI VKX8311 Klystron and a solid state ScandiNova k400 modulator to generate a maximum RF output power of 50 MW at 50 Hz, that will be mainly used for accelerating structure conditioning and waveguide components testing. In this paper the layout, the installation, commissioning and stability measurements of this source are described in detail. The test stand will be soon operative and ready to test the first X-band accelerating structure prototype., Proceedings of the 13th International Particle Accelerator Conference, IPAC2022, Bangkok, Thailand

In the framework of LATINO project (Laboratory in Advanced Technologies for INnOvation) funded by Lazio regional government, the commissioning of the TEst stand for X-band (TEX) facility has started in 2021 at Frascati National Laboratories of INFN. Born as a collaboration with CERN to test high gradient accelerating structures, during 2022 TEX aims at feeding the first EuPRAXIA@SPARC_LAB X-band structure prototype. During 2021 the commissioning has been successfully carried out up to 48 MW. The power unit is driven by an X-band low level RF system, that employs a commercial S-band (2.856 GHz) Libera digital LLRF (manufactured by Instrumentation Technologies), with an up/down conversion stage and a reference generation and distribution system able to produce coherent frequencies for the American S-band and European X-band (11.994 GHz), both designed and realized at LNF. The performance of the system, with a particular focus on amplitude and phase resolution, together with klystron and driver amplifier jitter measurements, will be reviewed in this paper. Moreover, considerations on its suitability and main limitations in view of EuPRAXIA@SPARC_LAB project will be discussed., Proceedings of the 13th International Particle Accelerator Conference, IPAC2022, Bangkok, Thailand

DAΦNE, the Frascati lepton collider, has completed the preparatory phase in order to deliver luminosity to the SIDDHARTA-2 detector. DAΦNE colliding rings rely on a new interaction region, which implements the well-established Crab-Waist collision scheme, and includes a low-beta section equipped with newly designed permanent magnet quadrupoles, and vacuum components. Diagnostics tools have been improved, especially the ones used to keep under control the beam-beam interaction. The horizontal feedback in the positron ring has been potentiated in order to achieve a higher positron current. Luminosity diagnostics have been also updated so to be compatible with the new detector design. The commissioning was initially focused on recovering the optimal dynamical vacuum conditions, outlining alignment errors, and optimizing ring optics. For this reason, a detuned optics, featured by relaxed low-b condition at the interaction point and Crab-Waist Sestupoles off, has been applied. In a second stage a low-b optics has been implemented to test collisions with a preliminary setup of the experiment detector. Machine preparation and the first luminosity results are presented and discussed., Proceedings of the 12th International Particle Accelerator Conference, IPAC2021, Campinas, SP, Brazil

We report the status of the development of an High Power RF Laboratory in X-Band called TEX (TEst-stand for X-Band). TEX is part of the LATINO (Laboratory in Advanced Technologies for INnOvation) initiative that is ongoing at the Frascati National Laboratories (LNF) of the Italian Institute for Nuclear Physics (INFN) that covers many different areas focused on particle accelerator technologies. TEX is a RF test facility based on solid-state K400 modulator from ScandiNova with a 50MW class X-band (11.996 GHz) klystron tube model vkx 8311a operating at 50 Hz. This RF source will operate as resource for test and research programs such as the RF breakdown on RF waveguide components as well as high power testing of accelerating structures for future high gradient linear accelerator such as EuPRAXIA and CLIC. The high power testing will be performed in a dedicated brand-new bunker that has been recently built. RF system, vacuum controls and safety equipments are currently being installed. The first accelerating structure testing is scheduled by beginning 2022. In this document design and tests for all the sub-systems of the facility will be presented and discussed., Proceedings of the 12th International Particle Accelerator Conference, IPAC2021, Campinas, SP, Brazil

In the framework of LATINO project (Laboratory in Advanced Technologies for INnOvation) funded by Lazio regional government, a TEst stand for X-band (TEX) is being commissioned at Frascati National Laboratories (LNF) of INFN. TEX is born as a collaboration with CERN, aimed at carrying out high power tests of X-band accelerating structure prototypes and waveguide components, and it is of paramount importance in view of the construction of EuPRAXIA@SPARC_LAB facility at LNF. In order to generate, manipulate and measure the RF pulses needed to feed the RF power unit (solid state ScandiNova K400 modulator, CPI 50 MW 50 Hz klystron) an X-band low level RF system has been developed, making use of a commercial S-band (2.856 GHz) Libera digital LLRF (manufactured by Instrumentation Technologies) with a newly designed up/down conversion stage and a reference generation/distribution system, which is able to produce coherent reference frequencies for the American S-band (2.856 GHz) and European X-band (11.994 GHz). In this paper the main features of such systems will be reviewed together with preliminary laboratory measurement results., Proceedings of the 12th International Particle Accelerator Conference, IPAC2021, Campinas, SP, Brazil

Optical Transition Radiation (OTR) screens are widely used for beam profile measurements. The radiation is emitted when a charged particle beam crosses the boundary between two media with different optical properties. The main advantages of OTR are the instantaneous emission process allowing fast single shot measurements (i.e. bunch by bunch measurements in a multi bunch machine), and the good linearity with the beam charge (if coherent effects can be neglected). Furthermore, OTR angular distribution strongly depends on beam energy. Since OTR screens are typically placed in several positions along the Linac to monitor beam envelope, one may perform a distributed energy measurement along the machine: this will be useful, for instance, during the commissioning phase of a machine. This paper deals with the studies of an algorithm to optimize the generation and the transport of the transition radiation through an optic system using the simulation tool Zemax. The algorithm, in combination with a particle tracking code (i.e. Elegant), will allow to simulate the radiation generated by a beam and, so, to take into account beam divergence and energy spread or chromatic effects in the optic system., Proceedings of the 10th Int. Particle Accelerator Conf., IPAC2019, Melbourne, Australia

The Extreme Light Infrastructure - Nuclear Physics Gamma Beam Source (ELI-NP GBS) will be installed and commissioned starting within the next year in Magurele, Romania. It will generate gamma beam through Compton back-scattering of a recirculated laser and a multi-bunch electron beam, produced by a 720 MeV LINAC. In order to obtain bunch by bunch position measurements, four cavity beam position monitors (cBPM) near the two interaction points are foreseen. Extensive tests on the cBPM read-out electronics, recently developed by Instrumentation Technologies and acquired for ELI-NP GBS, were performed in laboratory at INFN-LNF and at FLASH in DESY, during the user operation. In the latter case, three cBPMs installed along the LINAC, with similar features as the ones of ELI-NP GBS, were used as measuring devices and signal sources for the read-out electronics under test. We present here the measurements collected and the related analysis, with a particular focus on the beam position measurement resolution., Proceedings of the 9th Int. Particle Accelerator Conf., IPAC2018, Vancouver, BC, Canada

The R&D of high gradient radiofrequency (RF) devices is aimed to develop innovative accelerating structures based on new manufacturing techniques and materials in order to construct devices operating with the highest accelerating gradient. Recent studies have shown a large increase in the maximum sustained RF surface electric fields in copper structures operating at cryogenic temperatures. These novel approaches allow significant performance improvements of RF photoinjectors. Indeed the operation at high surface fields results in considerable increase of electron beam brilliance. This increased brilliance requires high field quality in the RF photoinjector and specifically in its power coupler. In this work we present a novel power coupler for the RF photoinjector. The coupler is a compact X-band TM01 mode launcher with a fourfold symmetry which minimized both the dipole and the quadrupole RF components., Proceedings of the 9th Int. Particle Accelerator Conf., IPAC2018, Vancouver, BC, Canada

A high brightness electron Linac is being built in the Compton Gamma Source at the ELI Nuclear Physics facility in Romania. To achieve the design luminosity, a train of 32 bunches, 16 ns spaced, with a nominal charge of 250 pC will collide with the laser beam in the interaction point. Electron beam spot size is measured with optical transition radiation (OTR) profile monitors. Furthermore, OTR angular distribution strongly depends on beam energy. Since OTR screens are typically placed in several positions along the Linac to monitor beam envelope, one may perform a distributed energy measurement along the machine. This will be useful, for instance, during the commissioning phase of the GBS in order to verify the correct functionality of the C-Band accelerating structures, due to the fact that there are OTR screens after each accelerating module. This paper deals with the studies of different optic configurations to achieve the field of view, resolution and accuracy in order to measure the energy of the beam. Several configurations of the optical detection line will be studied with simulation tools (e.g. Zemax)., Proceedings of the 9th Int. Particle Accelerator Conf., IPAC2018, Vancouver, BC, Canada

The Extreme Light Infrastructure ' Nuclear Physics Gamma Beam Source (ELI-NP GBS) facility will provide an high intensity laser and a very intense gamma beam for verious experiments. The gamma beam is generated through incoherent Compton back-scattering of a laser light off a high brightness electron beam provided by a 720MeV warm LINAC. The electrons are organized in compact trains with up to 32 bunches, each separated by 16ns. To optimize the laser-electron interaction and therefore the generation of the gamma rays, one big challenge is to precisely monitor the trajectory of each electron bunch. To match this requirement, at the interaction point two S-band cavity beam position monitors will be used, and the related readout system should perform bunch-by-bunch position measurements with sub-μm resolution. Using 500MS/s ADC converters and dedicated data processing, the readout system proposes an alternative measurement concept. In this paper the architecture of the system, the implemented signal processing and the results of the first laboratory tests will be presented., Proceedings of the 6th Int. Beam Instrumentation Conf., IBIC2017, Grand Rapids, MI, USA

Strip line Beam Positions Monitors (BPMs) are the main devices used for non-intercepting position measurement for the electron LINAC of ELI-NP (Extreme Light Infrastructure - Nuclear Physics). All the 29 BPMs have the same design, with the exception of the one installed in one of the dump line, which has a much larger acceptance than the others. BPMs will also be used to measure the charge of the beam, by measuring the sum of the pickups signals and calibrating it with beam charge monitors installed along the LINAC. An analytical model has been developed for the proposed BPMs. This model has been checked by means of PIC/wakefield simulations, in order to obtain the pickups signals at the passage of the beam and to study the effects of BPMs non-linearities, particularly on charge measurements. Details of the analytical model, results of the numerical simulations and the correction algorithm proposed for charge measurements are described in this paper., Proceedings of the 6th Int. Beam Instrumentation Conf., IBIC2017, Grand Rapids, MI, USA

A high brightness electron Linac is being built in the Compton Gamma Source at the ELI Nuclear Physics facility in Romania. To achieve the design luminosity, a train of 32, 16 ns spaced, bunches with a nominal charge of 250 pC will collide with the laser beam in the interaction point. Electron beam spot size is measured with an OTR (optical transition radiation) profile monitors. In order to measure the beam properties, the optical radiation detecting system must have the necessary accuracy and resolution. This paper deals with the studies of different optic configurations to achieve the magnification, resolution and accuracy desired considering design and technological constraints; we will compare several configurations of the optical detection line to justify the one chosen for the implementation in the Linac., Proceedings of the 5th Int. Beam Instrumentation Conf., IBIC2016, Barcelona, Spain

The advanced source of Gamma-ray photons will be soon built near Bucharest (Romania) by an European consortium (EurogammaS) led by INFN, as part of the ELI-NP (Extreme Light Infrastructure-Nuclear Physics). It will generate photons by Compton back-scattering in the collision between a multi-bunch electron beam, at a maximum energy of 720 MeV, and a high intensity recirculated laser pulse. An S-Band photo-injector and the following C-band Linac, which are under construction, will operate at 100Hz repetition rate with macro pulses of 32 electron bunches, separated by 16ns and with 250pC nominal charge. Stripline and cavity BPMs will be installed along the linac, in order to measure both the position and charge of the electron beam. Stripline BPM response can be considered linear within a limited area around the BPM origin. In order to use the full BPM acceptance area, without accuracy losses due to non-linearities, we plan to use correction algorithms, developed on the basis of simulations and measurements of BPMs response. In particular, suitable high-order surface polynomials will be used., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark

A high brightness electron Linac is being built in the Compton Gamma Source at the ELI Nuclear Physics facility in Romania. To achieve the design luminosity, a train of 32 bunches, 16 ns spaced, with a nominal charge of 250 pC will collide with the laser beam in the interaction point. Electron beam spot size is measured with optical transition radiation (OTR) profile monitors. In order to measure the beam properties, the optical radiation detecting system must have the necessary accuracy and resolution. This paper deals with the studies of different optic configurations to achieve the magnification, resolution and accuracy in order to measure very small beam (below 30 um) or to study the angular distribution of the OTR and therefore the energy of the beam. Several configurations of the optical detection line will be studied both with simulation tools (e.g. Zemax) and experimentally. The paper will deal also with the sensibility of optic system (in terms of depth of field, magnification and resolution) to systematic errors., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark

A high brightness electron LINAC is being built in the Compton Gamma Source at the ELI Nuclear Physics facility in Romania. To achieve the design luminosity, a train of 32 bunches, 16 ns spaced, with a nominal charge of 250 pC will collide with the laser beam in the interaction point at two electron beam energies, namely 280 MeV and 720 MeV. Electron beam spot size is measured with optical transition radiation (OTR) profile monitors. The paper deals with the possibility of using the OTR monitors to measure also beam energy along the machine; such measurements may help monitoring the accelerating sections performances, especially when the whole bunch train is being accelerated. We discuss the measurement principle, the expected accuracy and the main characteristic of the optical line to retrieve the angular distribution of the emitted radiation., Proceedings of the 6th Int. Beam Instrumentation Conf., IBIC2017, Grand Rapids, MI, USA

The advanced source of Gamma-ray photons to be built in Bucharest (Romania), as part of the ELI-NP European Research Infrastructure, will generate photons by Compton back-scattering in the collision between a multi-bunch electron beam and a high intensity recirculated laser pulse. An S-Band photoinjector and the following C-band Linac at a maximum energy of 720MeV, under construction by an European consortium (EurogammaS) led by INFN, will operate at 100Hz repetition rate with trains of 32 electron bunches, separated by 16ns and a 250pC nominal charge. The different BPMs and current transformers used to measure transverse beam position and charge along the LINAC are described. Design criteria, production status and bench test results of the charge and position pickups are reported in the paper, together with the related data acquisition systems., Proceedings of the 5th Int. Beam Instrumentation Conf., IBIC2016, Barcelona, Spain

CNAO, the Italian Centre of Oncological Hadrontherapy located in Pavia, is under commissioning and will be soon fully operational. It is based on a synchrotron that can accelerate carbon ions up to 400 MeV/u and protons up to 250 MeV for the treatment of patients. In this paper we present the subsystem, called B-Train, which has the purpose of measuring the magnetic field in a dedicated dipole connected in series with the sixteen dipoles of the synchrotron and to provide instantaneous values of the synchrotron field to the dipole power supply, to the RF, diagnostics and dump bumpers control systems, via optical lines, using a custom communication protocol. In order to measure the magnetic field with the specified precision (0.1G over 1.5T @ 3 T/s), a different approach has been taken with respect to previous versions of the system. The field is obtained by digitizing the voltage induced on a pick-up coil inserted in the gap of the dedicated dipole through a 18 bit, 1.25 Msamples/s ADC and integrating it by numerical methods. This paper describes the final design and features of the B-Train system, as well as the results obtained on the magnetic field readings precision., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

Colofón Sign.: [cruz latina]8, A-2F8 Port. a dos tintas, con grab. xil. Grabados xil. de edificios y esculturas de Roma