The DAΦNE operations during the last year have been devoted to deliver a statistically significant data sample to perform the first-ever measurement of kaonic deuterium X-ray transitions to the fundamental level. Operations for the SIDDHARTA-2 detector using a deuterium gas target started officially on the second half of May 2023, and have been organized in several runs here described.
Figure 20.1 was not correct in the published article. The original article has been corrected. The published apologizes for the inconvenience.
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.
This report presents the conceptual design of a new European research infrastructure EuPRAXIA. The concept has been established over the last four years in a unique collaboration of 41 laboratories within a Horizon 2020 design study funded by the European Union. EuPRAXIA is the first European project that develops a dedicated particle accelerator research infrastructure based on novel plasma acceleration concepts and laser technology. It focuses on the development of electron accelerators and underlying technologies, their user communities, and the exploitation of existing accelerator infrastructures in Europe. EuPRAXIA has involved, amongst others, the international laser community and industry to build links and bridges with accelerator science - through realising synergies, identifying disruptive ideas, innovating, and fostering knowledge exchange. The Eu-PRAXIA project aims at the construction of an innovative electron accelerator using laser- and electron-beam-driven plasma wakefield acceleration that offers a significant reduction in size and possible savings in cost over current state-of-the-art radiofrequency-based accelerators. The foreseen electron energy range of one to five gigaelectronvolts (GeV) and its performance goals will enable versatile applications in various domains, e.g. as a compact free-electron laser (FEL), compact sources for medical imaging and positron generation, table-top test beams for particle detectors, as well as deeply penetrating X-ray and gamma-ray sources for material testing. EuPRAXIA is designed to be the required stepping stone to possible future plasma-based facilities, such as linear colliders at the high-energy physics (HEP) energy frontier. Consistent with a high-confidence approach, the project includes measures to retire risk by establishing scaled technology demonstrators. This report includes preliminary models for project implementation, cost and schedule that would allow operation of the full Eu-PRAXIA facility within 8-10 years.
The PADME experiment [1] aims at searching for the dark photon (A') in the e+ > Ay' process in a positron -on-target experiment, exploiting the positron beam of the DADNE Linac at the INFN Frascati National Laboratory (Italy). The Linac can provide a number of positrons in excess of 1010 in a 200 ns long pulse but, in order to keep the pile-up probability in the calorimeter at an acceptable level, the number of positrons for PADME has to be below 105/pulse, in particular by using the attenuating target in the BTF beam-line. The experiment is then essentially limited by the low duty factor (10-5=200 ns/20 ms). In this paper, an alternative proposal to use the DADNE positron ring as a Linac pulse stretcher, by injecting each pulse into the ring and extracting it by a slow resonant extraction using the m/3 resonance, is presented. This would allow for distributing the positrons of a single Linac pulse over a much longer time interval (0.2-0.5 ms), increasing the duty factor up to 1%. The required modifications of the DADNE positron transfer line and ring are described. A dedicated lattice for the positron ring has been designed and tracking of the positrons injected in the ring has been performed in order to optimize the extraction parameters and to give a preliminary estimate of the extracted beam characteristics.
DAΦNE, the Italian lepton collider, is running since more than a decade thanks to a radical revision of the approach used to deal with the beam-beam interaction: the Crab-Waist Collision Scheme. In this context, the collider has recently completed a long term activity program aimed at providing an unprecedented sample of data to the KLOE-2 detector, a large experimental apparatus including a high intensity axial field strongly perturbing ring optics and beam dynamics. The KLOE-2 run has been undertaken with the twofold intent of collecting data for rare decay and flavor physics studies, and testing the effectiveness of the new collision scheme in presence of a strongly perturbing experimental apparatus. The performances of the collider are reviewed and the limiting factors discussed along with the preparatory phase activities planned to secure a new collider run to the SIDDHARTA-2 experiment.
On the wake of the results obtained so far at the SPARC_LAB test-facility at the Laboratori Nazionali di Frascati (Italy), we are currently investigating the possibility to design and build a new multi-disciplinary user-facility, equipped with a soft X-ray Free Electron Laser (FEL) driven by a ∼1 GeV high brightness linac based on plasma accelerator modules. This design study is performed in synergy with the EuPRAXIA design study. In this paper we report about the recent progresses in the on going design study of the new facility.
The ELI-NP GBS is a high intensity and monochromatic gamma source under construction in Magurele (Romania). The design and construction of the Gamma Beam System complex as well as the integration of the technical plants and the commissioning of the overall facility, was awarded to the Eurogammas Consortium in March 2014. The delivery of the facility has been planned in for 4 stages and the first one was fulfilled in October 31st 2015. The engineering aspects related to the delivery stage 1 are presented.
After a long preparatory phase, including a wide hardware consolidation program, the Italian lepton collider DAFNE, is now systematically delivering data to the KLOE-2 experiment. In approximately 200 days of operation 1 fb-1 has been given to the detector limiting the background to a level compatible with an efficient data acquisition. Instantaneous and maximum daily integrated luminosity measured, so far, are considerably higher with respect to the previous KLOE runs, and are: L(inst) ~ 2.0 1032 cm-2s-1, and L(day) ~ 12.5 pb-1 respectively. A general review concerning refurbishing activities, machine optimization efforts and data taking performances is presented and discussed.
In the first six months of 2013 the KLOE detector has been upgraded inserting new layers in the inner part of the apparatus, around the interaction region. The long shutdown has been used to implement a general consolidation program aimed at improving the Φ-Factory operation stability and reliability and, in turn, the collider uptime. In this context several systems have been revised and upgraded, new diagnostic elements have been installed, some critical components have been modified and the interaction region mechanical support structure has been redesigned to improve its mechanical stability and to deal with the weight added by the new detector layers.
The transfer lines of the DAΦNE accelerator complex have been revised and optimized in view of the forthcoming KLOE-2 physics run. The transfer lines consolidation activities involved low level systems, diagnostics tools and control system procedures dealing with polarity switch of the magnetic element during the injection. The work done determined a substantial improvement in the transfer lines stability and reproducibility, speeding up the polarity switch and increasing the injection efficiency thus achieving a considerable reduction of the background hitting the experimental detector during the process.
A new era of laser based plasma accelerators is emerging following the commissioning of many high power laser facilities around the world. Extremely short (tens of fs) laser pulses with energy of multi-joules level are available at these newly built facilities. Here we describe the new 220 TW FLAME facility. In particular we discuss the laser system general layout, the main measurements on the laser pulse parameters, the underground target area. Finally we give an overview of the first results of the Self-Injection Test Experiment (SITE), obtained at a low laser energy. This initial low laser energy experimental campaign was necessary for the validation of the radio-protection shielding (Esposito, 2011 [1]) we discuss here. With respect to our preliminary configuration, with a pulse duration of 30 fs and a focusing optic of F/15, we discuss here the minimum laser energy requirements for electron acceleration and the forward transmitted optical radiation.
The SuperB collider project has been recently approved by the Italian Government as part of the National Research Plan. SuperB is a high luminosity (10{sup 36} cm{sup -2} s{sup -1}) asymmetric e{sup +}e{sup -} collider at the {Upsilon}(4S) energy. The design is based on a 'large Piwinski angle and Crab Waist' scheme already successfully tested at the DAPHNE {Phi}-Factory in Frascati, Italy. The project combines the challenges of high luminosity colliders and state-of-the-art synchrotron light sources, such as two beams (e{sup +} at 6.7, HER, and e{sup -} at 4.2 GeV, LER) with extremely low emittances and small beam sizes at the Interaction Point. As unique features, the electron beam will be longitudinally polarized at the IP and the rings will be able to ramp down to collide at the {tau}/charm energy threshold with a luminosity of 10{sup 35} cm{sup -2} s{sup -1}. The relatively low beam currents (about 2 A) will allow for low running (power) costs compared to similar machines. The insertion of beam lines for synchrotron radiation (SR) users is the latest feature included in the design. The lattice has been recently modified to accommodate insertion devices for X-rays production.
In its continuous evolution DANE, the Frascati lepton collider, is starting a new run for the KLOE-2 detector, an upgraded version of the KLOE one. A new interaction region, based on the high luminosity Crab-Waist collision scheme, has been designed, built and installed. Several machine subsystems have been revised according innovative design concepts in order to improve beam dynamics. Collimators and detector shields have been upgraded in order to minimize the background hitting the experimental apparatus during coasting as well as injection operation. A wide measurement campaign has been undertaken to verify and quantify the effect of the modifications and to tune-up the collider in view of the 3 years long data-taking that should deliver ~ 5 fb -1 to the KLOE-2 experiment.
In the second half of 2007 a major upgrade has been implemented on the Frascati DA{Phi}NE collider in order to test the novel idea of Crab-Waist collisions. New vacuum chambers and permanent quadrupole magnets have been designed, built and installed to realize the new configuration. At the same time the performances of relevant hardware components, such as fast injection kickers and shielded bellows have been improved relying on new design concepts. The collider has been successfully commissioned in this new configuration. The paper describes several experimental results about linear and non-linear optics setup and optimization, damping of beam-beam instabilities and discusses the obtained luminosity performances. DA{Phi}NE [1] is the Frascati lepton collider working at the c m. energy of the {Phi} meson resonance (1020). It came in operation in 2001 and till summer 2007 provided luminosity, in sequence, to three different experiments which logged a total integrated luminosity of {approx} 4.4 fb{sup -1}. During these years the collider reached its best performances in terms of luminosity and background (L{sub peak} = 1.6 x 10{sup 32} cm{sup -2}s{sup -1} L{sub day} {approx} 10 pb{sup -1}) by means of several successive upgrades, relying on the experience gathered during the collider operations andmore » implemented exploiting the shutdowns required for the experiment change over [2, 3, 4].« less
In 2007 DA NE was upgraded to operate in a regime of large Piwinski angle, with a novel interaction region optics, reduced vertical beta at the interaction point, and additional sextupoles providing for Crab-Waist collisions. The specific luminosity has been boosted by more than a factor of four at low currents, and the present peak luminosity is by about a factor of 3 higher than the maximum value obtained with the original collider configuration. The DA NE commissioning as well as the first experience with large Piwinski angle and Crab-Waist collisions scheme will be reported.
Recently the peak luminosity achieved on the DA{\Phi}NE collider has been improved by almost a factor three by implementing a novel collision scheme based on large Piwinski angle and Crab-Waist. This encouraging result opened new perspectives for physics research and a new run with the KLOE-2 detector has been scheduled to start by spring 2010. The KLOE-2 installation is a complex operation requiring a careful design effort and a several months long shutdown. The high luminosity interaction region has been deeply revised in order to take into account the effect on the beam caused by the solenoidal field of the experimental detector and to ensure background rejection. The shutdown has been also used to implement several other modifications aimed at improving beam dynamics: the wiggler poles have been displaced from the magnet axis in order to cancel high order terms in the field, the feedback systems have been equipped with stronger power supplies and more efficient kickers and electrodes have been inserted inside the wiggler and the dipole vacuum chambers, in the positron ring, to avoid the e-cloud formation. A low level RF feedback has been added to the cavity control in both rings.