Periodic Reporting for period 2 - E-JADE (Europe-Japan Accelerator Development Exchange Programme)
Reporting period: 2017-01-01 to 2018-12-31
Scientifically, E-JADE evolved around three topics, all providing excellent training grounds for young researchers:
i) Firstly, R&D for future hadron colliders and in particular the development of magnets for these machines profited massively from the exchange of staff between Japan and Europe. European secondments provided essential support to the Japanese developments for the necessary upgrades of the LHC accelerator complex.
ii) Secondly, at the Japanese ATF2 and SuperKEKB facilities at KEK, studies towards nanometer-scale beams for future lepton accelerators were carried out. This is largely generic R&D that will benefit any future research direction in accelerator science, and E-JADE could contribute significantly.
iii) Thirdly, work was continued towards future linear colliders, in particular the International Linear Collider (ILC). With the European XFEL – technology-wise a 10% prototype for the ILC – recently completed at DESY in Hamburg, European know-how in terms of design, integration, and production as well as documentation is vital for the ILC, and European industry is well positioned to contribute to the mass-production of accelerator structures. However, the design and layout need to be adapted to the specifics of the suggested cite in Japan, and E-JADE was instrumental in this respect as well.
Work in WP 1 has in general progressed on all fronts, with numerous E-JADE-supported secondments in both directions; the maybe most important achievement being the large Japanese contributions to the operation, upgrade and other activities of the ATLAS experiment and the construction, test and re-assembly of the D1 short prototype beam separation dipole magnet for the High Luminosity LHC upgrade.
WP 2 covered work at the Accelerator Test Facility (ATF2) at KEK operating an electron damping ring with ultra-low transverse emittance. The main objective of this work package was to demonstrate solutions and methods for final focus systems for future linear colliders.
Work package 2 has made excellent progress, commanding by far the highest number of E-JADE secondments. Important achievements of WP 2 are the assessment of the role of higher-order aberrations for the beam size, better understanding of wakefield sources at the ATF2, a full proof-of-principle demonstration of an orbit feed-forward scheme based on ground motion sensors placed on top of quadrupoles, a full characterisation of the vertical beam halo distribution, including reliable theoretical modelling, as well as first time measurements of the momentum distribution with a newly developed combined YAG/OTR monitor, using a new experimental technique, first-time non-invasive beam size measurements with the newly developed ODR/OTR monitor and substantial improvements in the achieved stabilisation of the beam at the interaction point using the IP-BPM and FONT intra-train beam-feedback systems.
WP 3 “Linear collider targeted R&D” had as main objectives the development of the site-specific design for the International Linear Collider (ILC) in Japan and a project implementation plan involving European participation at an appropriate level. Concretely, a completed preparation phase with a site-specific design and the preparation of the construction were envisaged during the E-JADE project duration. However, WP 3 has suffered from the unforeseen delay of the ILC project.
WP3 achievements comprise a detailed study of the various integration issues that will be encountered at the proposed Kitakami site and a detailed assessment of the ILC baseline change from a 500 GeV to a 250 GeV machine. This together with restating the case of how important positron polarization is for the ILC physics case are a key outcome of WP3 – together with the above-mentioned European preparation plan (“EIPP”) that was submitted in June 2018.
There is also a long-standing collaboration between Europe and KEK on the development and testing of 12 GHz copper RF structures for use at a CLIC-based linear collider. During 2015-16, the two test stands at KEK and CERN had been used to characterise CLIC accelerating structures.
WPs 4 and 5 also successfully executed their programmes, with major achievements being the installation of CERN-KEK offices, the implementation and execution of the envisaged communication strategy including numerous actions at all beneficiaries and partner institutions, and the evaluation of the secondment success based on a tool implemented for the purpose.
Progress beyond state-of-the-art was achieved in all three scientific work packages of the programme, be it within WP1 and the CENR LIU project with the implementation of the first HL-LHC dipole, with the superior results on nanometer beams at the ATF2 in WP 2, and with new results on CLIC accelerating structures or the European Implementation Plan for the ILC, both in WP 3.
Given the continuing spread of accelerators in science, technology and society (i.e. for medical applications, industrial processes, material characterization, pharmaceutical research, cultural heritage studies, life sciences at broad level etc.), the students and postdocs seconded by E-JADE will be highly sought after by industry and research centers providing these services to industry and scientists.
The societal impact is therefore though openly published technical developments in the projects supported by E-JADE, and training of young accelerator scientist, most of which will have careers in accelerator physics where the main purpose of the facilities will be in the fields mentioned above.