素粒子物理学における欧州の未来戦略
2013年のアップデート
2013年5月30日にブリュッセルで開かれたCERN理事会の欧州戦略のための特別会合で承認された*)。以下はその最重要部分の和訳である。
４つの最も高い優先項目：
多くの資源と幅広くて持続する協力が必要とされる可能な大規模科学研究を数多くかつ注意深く調査分析した結果、次の４つの研究計画が最も高い優先度を有していると結論するに至った。
c. ヒッグス粒子の発見は、この粒子の性質を可能な限り高い精度で測定して標準模型の確実性を確立し、さらにエネルギー最前線で更なる新しい物理を探索するための研究、の始まりにすぎない。欧州のトッププライオリティは、2030年頃までに設計値の10倍のデータを集めることを目指して、加速器と測定器の高輝度アップグレードを行い、LHCの可能なすべての性能を発揮して探求を行う。ここではフレーバー物理とクォーク・グルーオンプラズマ物理の新たな結果も期待される。
d. 素粒子物理学の最前線に留まるために、１４TeVでのLHC運転による物理の結果が出た後に開かれる次の欧州戦略のアップデートまでに、欧州はCERNに置く野心的なポストLHC加速器計画を提案する必要がある。CERNは陽子・陽子と電子・陽子衝突を主とした高エネルギー最前線の加速器計画の設計作業を国立研究所や大学と協力して世界規模で進める。この設計作業には、高い磁場と高い加速勾配構造他の種々の加速器技術の研究開発を含む。
e. ヒッグス粒子の性質と他の粒子をかってないほどの高精度で研究し、かつエネルギーが高くする可能性を持つ電子・陽電子衝突装置には、LHCと相補的な強い科学的な意義が存在する。多くの欧州からの協力も得て、国際リニアーコライダー(ILC)の技術設計書が完成した。日本の素粒子物理学分野が率先して日本にILCを誘致することを最も歓迎し、欧州グループの参加を強く期待している。欧州は参加の可能性を議論するために日本からの提案を期待している。
f. 多くの欧州の研究者の協力を得て、ニュートリノ振動物理は早いスピードで進展してきており、ニュートリノ関係のCP非保存と質量の階層性を探求するための長い基底距離のニュートリノ研究は重要であることがわかってきた。CERN は将来の長基底距離のニュートリノ実験において欧州が重要な役割を果たす道筋を作るべきである。欧州は米国や日本で行われる先進的な長い基底距離のニュートリノ計画に大々的に参加することを検討するべきである。
*)

原文のThe European strategy for particle physicsはhttp://cds.cern.ch/record/1551933/files/Strategy_Report_LR.pdf のページ
20-23にある。

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The European strategy for particle physics

The European Strategy for Particle Physics
Update 2013
Preamble
Prepared by the European
Strategy Group for Particle
Physics for the special
European Strategy Session ofCouncil in Brussels on 30 May
2013.

Since the adoption of the European Strategy for Particle Physics
in 2006, the field has made impressive progress in the pursuitof its core mission, elucidating the laws of nature at the mostfundamental level. A giant leap, the discovery of the Higgs boson,has been accompanied by many experimental results confirming
the Standard Model beyond the previously explored energy scales.
These results raise further questions on the origin of elementary
particle masses and on the role of the Higgs boson in the more
fundamental theory underlying the Standard Model, which may
involve additional particles to be discovered around the TeV scale.
Significant progress is being made towards solving long-standing
puzzles such as the matter-antimatter asymmetry of the Universe
and the nature of the mysterious dark matter. The observation ofa new type of neutrino oscillation has opened the way for future
investigations of matter-antimatter asymmetry in the neutrino
sector. Intriguing prospects are emerging for experiments at theoverlap with astroparticle physics and cosmology. Against thebackdrop of dramatic developments in our understanding of thescience landscape, Europe is updating its Strategy for Particle Physics
in order to define the community’s direction for the coming years
and to prepare for the long-term future of the field.

General issues
a. The success of the LHC is proof of the effectivenessof the European organizational model for particle
physics, founded on the sustained long-term
commitment of the CERN Member States and of
the national institutes, laboratories and universities
closely collaborating with CERN. Europe shouldpreserve this model in order to keep its leadingrole, sustaining the success of particle physics
and the benefits it brings to the wider society.
b. The scale of the facilities required by particle physics
is resulting in the globalisation of the field. The
European Strategy takes into account the worldwide
particle physics landscape and developments inrelated fields and should continue to do so.

High priority large-scalescientific activities
After careful analysis of many possible largescale scientific activities requiring significant
resources, sizeable collaborations and sustainedcommitment, the following four activities havebeen identified as carrying the highest priority.
c. The discovery of the Higgs boson is the start of amajor programme of work to measure this particle’s
properties with the highest possible precision
for testing the validity of the Standard Model andto search for further new physics at the energy
frontier. The LHC is in a unique position to pursue
this programme. Europe’s top priority should be
the exploitation of the full potential of the LHC,The European strategy for particle physics

including the high-luminosity upgrade of themachine and detectors with a view to collecting
ten times more data than in the initial design, byaround 2030. This upgrade programme will also
provide further exciting opportunities for the studyof flavour physics and the quark-gluon plasma.
d. To stay at the forefront of particle physics, Europe
needs to be in a position to propose an ambitious
post-LHC accelerator project at CERN by the time of
the next Strategy update, when physics results fromthe LHC running at 14 TeV will be available. CERN
should undertake design studies for accelerator
projects in a global context, with emphasis on
proton-proton and electron-positron high-energy
frontier machines. These design studies should becoupled to a vigorous accelerator R&D programme,
including high-field magnets and high-gradientaccelerating structures, in collaboration with nationalinstitutes, laboratories and universities worldwide.
e. There is a strong scientific case for an electronpositron collider, complementary to the LHC, thatcan study the properties of the Higgs boson andother particles with unprecedented precision andwhose energy can be upgraded. The Technical
Design Report of the International Linear Collider(ILC) has been completed, with large Europeanparticipation. The initiative from the Japaneseparticle physics community to host the ILC in Japanis most welcome, and European groups are eager
to participate. Europe looks forward to a proposal
from Japan to discuss a possible participation.
f.

Rapid progress in neutrino oscillation physics, withsignificant European involvement, has establisheda strong scientific case for a long-baseline neutrino
programme exploring CP violation and the mass
hierarchy in the neutrino sector. CERN should
develop a neutrino programme to pave the way fora substantial European role in future long-baseline
experiments. Europe should explore the possibilityof major participation in leading long-baseline
neutrino projects in the US and Japan.

Other scientific activities essential tothe particle physics programmeg. Theory is a strong driver of particle physics andprovides essential input to experiments, witness themajor role played by theory in the recent discoveryof the Higgs boson, from the foundations of theStandard Model to detailed calculations guiding
the experimental searches. Europe should support
a diverse, vibrant theoretical physics programme,
ranging from abstract to applied topics, in close
collaboration with experiments and extending toneighbouring fields such as astroparticle physics andcosmology. Such support should extend also to highperformance computing and software development.
h. Experiments studying quark flavour physics,investigating dipole moments, searching forcharged-lepton flavour violation and performing
other precision measurements at lower energies,
such as those with neutrons, muons and antiprotons,
may give access to higher energy scales than direct
particle production or put fundamental symmetries
to the test. They can be based in nationallaboratories, with a moderate cost and smaller
collaborations. Experiments in Europe with uniquereach should be supported, as well as participationin experiments in other regions of the world.
i.

The success of particle physics experiments, suchas those required for the high-luminosity LHC,
relies on innovative instrumentation, state-of-theart infrastructures and large-scale data-intensivecomputing. Detector R&D programmes should be
supported strongly at CERN, national institutes,laboratories and universities. Infrastructure andengineering capabilities for the R&D programmeand construction of large detectors, as well as
infrastructures for data analysis, data preservationanddistributed
data-intensive
computingshould be maintained and further developed.

j.

A range of important non-accelerator experiments
take place at the overlap of particle andastroparticle physics, such as searches for proton
decay, neutrinoless double beta decay and dark
matter, and the study of high-energy cosmic-rays.
These experiments address fundamental questions
beyond the Standard Model of particle physics. The21

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The European strategy for particle physics

exchange of information between CERN and ApPEC
has progressed since 2006. In the coming years,
CERN should seek a closer collaboration with ApPEC
on detector R&D with a view to maintaining thecommunity’s capability for unique projects in this field.
k.

A variety of research lines at the boundary
between particle and nuclear physics require
dedicated experiments. The CERN Laboratory
should maintain its capability to perform uniqueexperiments. CERN should continue to workwith NuPECC on topics of mutual interest.

Organizational issuesl.

Future major facilities in Europe and elsewhererequire collaboration on a global scale. CERN shouldbe the framework within which to organise a global
particle physics accelerator project in Europe, andshould also be the leading European partner in global
particle physics accelerator projects elsewhere.
Possible additional contributions to such projects
from CERN’s Member and Associate Member
States in Europe should be coordinated with CERN.

m. A Memorandum of Understanding has beensigned by CERN and the European Commission,and various cooperative activities are under way.
Communication with the European Strategy Forumon Research Infrastructures (ESFRI) has led toagreement on the participation of CERN in therelevant ESFRI Strategy Working Group. The particle
physics community has been actively involved inEuropean Union framework programmes. CERN andthe particle physics community should strengthen
their relations with the European Commission inorder to participate further in the development of
the European Research Area.

Wider impact of particle physics
n. Sharing the excitement of scientific discoveries
with the public is part of our duty as researchers.
Many groups work enthusiastically in publicengagement. They are assisted by a network ofcommunication professionals (EPPCN) and aninternational outreach group (IPPOG). For example,

they helped attract tremendous public attention andinterest around the world at the start of the LHC andthe discovery of the Higgs boson. Outreach andcommunication in particle physics should receive
adequate funding and be recognised as a centralcomponent of the scientific activity. EPPCN andIPPOG should both report regularly to the Council.
o. Knowledge and technology developed for particle
physics research have made a lasting impact onsociety. These technologies are also being advancedby others leading to mutual benefits. Knowledge
and technology transfer is strongly promoted inmost countries. The HEPTech network has beencreated to coordinate and promote this activity,
and to provide benefit to the European industries.
HEPTech should pursue and amplify its efforts
and continue reporting regularly to the Council.
p. Particle physics research requires a wide rangeof skills and knowledge. Many young physicists,
engineers and teachers are trained at CERN,
in national laboratories and universities. They
subsequently transfer their expertise to society andindustry. Education and training in key technologies
are also crucial for the needs of the field. CERN,
together with national funding agencies, institutes,
laboratories and universities, should continue
supporting and further develop coordinatedprogrammes for education and training.

Concluding recommendations
q. This is the first update of the European Strategy forParticle Physics. It was prepared by the European
Strategy Group based on the scientific input fromthe Preparatory Group with the participation ofrepresentatives of the Candidate for Accession toMembership, the Associate Member States, theObserver States and other organizations. Such
periodic updates at intervals of about five years areessential. Updates should continue to be undertaken
according to the principles applied on the present
occasion. The organizational framework for theCouncil Sessions dealing with European Strategymatters and the mechanism for implementation andfollow-up of the Strategy should be revisited in thelight of the experience gained since 2006.

項目d. に関する参考情報

ECFA High Luminosity LHC Experiments Workshop
2013年10月1～10月3日 at Aix-les-Bains

CERN Perspective

by Rolf Heuer (CERN) の発表*)よりコピーした図*)
http://indico.cern.ch/getFile.py/access?contribId=6&sessionId=1&resId=1&materialId=slides&confId=252045