Interim Report from ad hoc committee on the Linear Collider Project

January 30, 2006
Ad hoc committee on the Linear Collider Project

The member list of this ad hoc committee is as follows:

Akihito ARIMAChairman of the Japan Science Foundation
Motoyuki ONOPresident of Japan Society for the Promotion of Science
Yoshitaka KIMURAProfessor Emeritus, High Energy Accelerator Research Organization
Takeshi KOMURAGovernor of Development Bank of Japan
Takeshi SASAKIProfessor, Gakushuin University
Hirotaka SUGAWARAExecutive Director of The Graduate University for Advanced Studies (chairman)
Seiichi TAKAYANAGITechnology Advisor of TOSHIBA Corporation
Yuichi TAKAYANAGIDirector of Tamarokuto Science Center
Muneyuki DATE President of Foundation Advanced Technology Institute

1. Preamble

The purpose of this ad hoc committee is to advise the Director General (DG) of the High Energy Accelerator Research Organization (KEK), concerning appropriate actions to take towards realization of the future "Linear Collider" (LC) Project. The LC Project is currently being pursued by members of the high energy physics community in the world, notably by those from Japan and countries in Asia, North America and Europe. This ad hoc committee was formed in 2005 in response to a request by the KEK DG, and its discussion topics include the issues associated with inviting the LC Project and hosting it in Japan. This document is an interim report by this ad hoc committee as a result of eight meetings that have been held since February, 2005 (Feb. 25, Apr. 8, May 30, Sep. 5, Oct. 31 and Dec 21 in 2005, and Jan. 30 in 2006).

2. Significance of Linear Collider and its Present Status

The Linear Collider (LC) is a particle accelerator which accelerates electron and positron beams to 250 GeV for beam collisions at a center-of-mass energy of 500 GeV. In a later stage the beam energies would be raised to 500 GeV, resulting in beam collisions at a center-of-mass energy of 1 TeV. The electron and positron beams are accelerated by microwave fields accumulated in highly efficient superconducting accelerator cavities, made of niobium. Present technical studies envisage that the total length of the accelerator facility would amount to approximately 50 km, and the entire accelerator would be installed inside underground tunnels. This is so as to minimize the environmental impact on the ground surface, as well as to reduce mechanical vibrations originating from surface activities which affect the stable operation of the accelerator.

The LC aims to conduct high-precision studies of particle interactions at high energies, and to resolve the remaining, unanswered questions in the field of High Energy Physics. One such question is the origin of mass. Another is how the four kinds of forces (the weak force, the electromagnetic force, the strong force, and gravity), which are currently well known, would be unified at a very high energy scale. In addition, the LC is expected to elucidate the identity of dark matter, which is considered to account for about 23% of all cosmic energy. The LC might reveal new phenomena which point to the possibility of the Universe having a space-time structure of more than 4 dimensions, and which would mark a breakthrough towards super unification theories that incorporate gravity.

The LC concept has been developed by the world's high energy physicists for more than ten years. In 2004, the ICFA (International Committee for Future Accelerators), on behalf of the world high energy physics community, decided to consolidate the world development efforts on the LC and to launch its first step, the "Global Design Efforts" (GDE).

The ICFA named the LC Project, as pursued under GDE, the "ILC", which stands for "International Linear Collider." In 2005, the GDE began its activity as a distributed organization with participation by scientists from the world. In December, 2005 the GDE published a Baseline Configuration Document (BCD) for ILC. Based on the BCD, by the end of 2006, the GDE plans to complete a Reference Design Report (RDR) which is augmented by substantial conceptual design and cost studies incorporating sample site conditions. The ILC is a very large-scale, high-precision facility which integrates state-of-the-art technologies from the areas of microwave generation and control, superconducting materials and cryogenics, ultra high-precision instrumentation, high-speed versatile controls, high-speed computing and communication. Development programs for these technologies are being vigorously pursued at major laboratories around the world, including KEK. The successful construction of ILC is expected to mark a profound positive impact on society both in terms of technology and sociology.

Since the 1970's, research programs in high energy physics in Japan have seen leap-frog growth through successful construction and operation of the electron-positron collider TRISTAN and its successor KEKB. Japanese excellence in detectors and accelerator technologies, including those related to superconducting cavities, is on a par with any region in the world that are active in these fields. The research programs, which have been producing top-level physics outputs at a world standard, have also produced a pool of very competent scientists and engineers who are capable of managing complex research projects in a fully international setting.

ILC will be a large project of unprecedented scale in basic science, to be executed through a global collaboration. Japan, with its highly competitive technology base and human resources, is capable of playing a leading role there, including hosting of this project. By doing so, Japan will have an excellent opportunity to make major contributions on multiple fronts within society, both domestic and international, such as advancing the progress of world high energy physics, underlining the Japanese presence in the area of basic science research in the world, stimulating incentives for technological competitiveness in industry, and attracting the younger generations in Asia and Japan to the fields of high-technologies and basic science, to name a few.

3. Recommendations

Recommendations compiled by this ad hoc committe concerning the actions to take for the KEK DG towards realization and hosting of the ILC Project are summarized as follows :

  1. With the recognition of the critical importance of the research programs at the ILC Project, the ad hoc committee recommends the KEK DG work closely with the government and research institutes abroad on matters related to advancement of this project.

    In the light of development of project promotion in the US and discussion at FALC that are intensifying on the activities of GDE, the KEK DG should maintain a very close contact with the government and relevant community leaders to exchange all critical information for optimal action planning.

    We need to value the relationships with other Asian countries. The KEK DG should keep close contacts and hold discussions with related agencies in order to establish intimate collaboration with other Asian countries, and he/she should promote the agenda of the ministerial committee for science and technology in Asia that is described in Report No. 5 "Basic Policies on Science and Technology" recommended by Council for Science and Technology Policy, dated December 27, 2005.

  2. Those scientists who wish to promote this project must make their best efforts to gain the public's understanding and support by appealing to the magnificence of Nature and the scientific dream of unraveling its mystery whenever possible. The target audience includes members of other fields of science, people in the political, bureaucratic and industrial sectors, the mass media, as well as the general public. The KEK DG should spearhead this effort while requesting the understanding and cooperation of all scientists in the relevant fields.

  3. While the GDE has issued the Baseline Configuration Document (BCD) for the ILC, it does not contain any reference to an Asian sample site to consider for modeling a realistic cost studies. The KEK DG should quickly introduce a suitable description of the Asian sample site in the BCD. The Asian region should not fall behind other regions in the area of detailed cost studies with a realistic sample site.

  4. KEK DG should lead the studies on a suitable international organizational structure for first promoting, then later executing, the ILC Project, with particular attention to its timely realization and later to hosting of the project in Japan. The KEK DG should lead the efforts to examine the role of KEK in that regard, including its possible reorganization in the future. The importance of aiming at the promotion of all scientific research in Japan must be noted.

Last modified: Fri Mar 3 19:46:08 JST 2006