International Cooperation in High Energy Physics

International Cooperation

in

High Energy Physics

Barry BarishCaltech30-Oct-06

30-Oct-06 Hawaii DPF 2

International Collaboration a brief history

• The Beginning of Modern Particle Physics– The Discovery of the Meson (1947) by Cecil Powell of the

University of Bristol, using photographic emulsions at sites located at high altitude mountains (first at Pic du Midi de Bigorre in the Pyrenees and later at Chacaltaya in the Andes

– This led to an international collaboration searching for cosmic ray interactions using an American balloon and British emulsions.



• Then Began the Era of Large Particle Accelerators– Required significant resources– I.I. Rabi in recognized and stated, “the urgency of creating

regional centres and laboratories in order to increase and make fruitful the international collaboration of scientists in fields where the effort of any one country is insufficient for the task.”

– This soon led to accelerator projects at BNL (1947) and the setting up of CERN in Geneva in 1952

CERNSynchro-Cyclotron600 MeV

1957



• Big Bubble Chambers (1960s)

– Large (often international) teams formed to analyze millions of pictures



• Big Bubble Chambers (1960s)– Large (often international) teams formed to analyze

millions of pictures– This led to the discovery of the large number of “so-

called” elementary particles

– SU(3) and the Quark Model made sense of this jungle of particles

Discovery of

Omego-minus



• Scintillators, Spark Chambers and Triggered Experiments (the alternate approach)– Discoveries - antiprotons; CP violation; two neutrinos; etc



• Then the November Revolution (1974)– The unexpected discovery of the J/

Proton CollisionsBig Electronic Detector

Electron PositronBig Collider Detector



• The Beginning of the Era of the Collider – Large Magnetic Detectors and Large International

Collaborations– The Standard Model confirmed in detail at LEP

– ALEPH - 400 physicists from 32 institutes in 10 countries.



• Large non-Accelerator Detectors – Neutrino Oscillations

SuperKamiokande KamLAND

SNO Detector



• B factories – Belle and BaBar– CP Violation in B Physics



• Emergence of Particle Astrophysics– Highest Energy Cosmic Rays

– The Interface of Particle Physics and High Energy Cosmic Ray Physics



• Emergence of Particle Astrophysics– TeV Gamma Ray Astronomy

– The Interface of Particle Physics and Astrophysics


Pacific Region


Pacific Regionhuman resources


Pacific Regiongrowing economic power


Pacific Regiongrowing economic power


U.S. West Coast The Role of the Pacific Region

• The B-factories– SLAC

– LBNL and the West Coast Universities – Univ of California; Caltech; Stanford; Oregon etc.


U.S. – Univ of Hawaii The Role of the Pacific Region

Hawaii

Anita

Belle

SuperK

BES


U.S. – Univ of Hawaii The Role of the Pacific Region

• KamLAND …

reaches the earth’s center


JAPAN The Role of the Pacific Region

• Superkamiokande• KamLAND

• KEK – Belle (CP; B Physics)


Emerging Asia The Role of the Pacific Region

• China

• India


Emerging Asia The Role of the Pacific Region

• Korea– Long Baseline Neutrinos


International Collaboration how did we get here?

• Theorists have collaborated worldwide scientist to scientist with few barriers

• Experimentalists also developed scientist to scientist collaboration internationally, but involves resources.

• International Union for Physics and Applied Physics (IUPAP) created the International Committee for Future Accelerators (ICFA) in 1976– ICFA sponsored a resolution which was supported by all

the existing laboratories (and by implication, the sponsoring agencies) to the effect that criteria for acceptance of proposals on high energy accelerator facilities should be based only on scientific merit and ability of the proposers to carry out the research.


International Collaboration now and in the future

• Experiments in all areas are performed by large international collaborations

• Facilities – Accelerators; Underground Facilities; Space are generally supported nationally or regionally

• The next step is internationalizing the facilties for the next generation of science– Large Hadron Collider – Regional with International

Participants– International Linear Collider – International from Concept

to Proposal to Governance to the Science


International Collaboration what’s the future?

• ICFA has continued for 50 years to lead in the development of the field and the use of facilities – Accelerator R&D– Computer networking– Large Collaborations

• Recent statements and actions toward the International Linear Collider have been crucial

• CERN is our closest approximation of an international laboratory -- LHC is the next big facility in the field, involving CERN member states and many others.


Accelerators and the Energy FrontierLarge Hadron Collider

CERN – Geneva Switzerland


Electron Positron CollidersThe Energy Frontier


Why e+e- Collisions ?

• elementary particles

• well-defined – energy,

– angular momentum

• uses full COM energy

• produces particles democratically

• can mostly fully reconstruct events


Electroweak Precision Measurements

What causes mass??

0

2

4

6

10020 400

mH GeV

Excluded Preliminary

had =(5)

0.027610.00036

0.027470.00012

Without NuTeV

theory uncertainty

Winter 2003

The mechanism – Higgs or alternative appears around the corner


The linear collider will measure the spin of any Higgs it can produce by measuring the energy dependence from threshold

How do you know you have discovered the Higgs ?

Measure the quantum numbers. The Higgs must have spin zero !


International Technology Review Panel


The ITRP Recommendation

• We recommend that the linear collider be based on superconducting rf technology

– This recommendation is made with the understanding that we are recommending a technology, not a design. We expect the final design to be developed by a team drawn from the combined warm and cold linear collider communities, taking full advantage of the experience and expertise of both (from the Executive Summary).


SCRF Technology Recommendation

• The recommendation of ITRP was presented to ILCSC & ICFA on August 19, 2004 in a joint meeting in Beijing.

• ICFA unanimously endorsed the ITRP’s recommendation on August 20, 2004


2003 年 7 月

Asia

Global Effort on Design / R&D for ILC

Joint Design, Implementation, Operations, ManagementHost Country Provides Conventional Facilities

EU US


main linacbunchcompressor

dampingring

source

pre-accelerator

collimation

final focus

IP

extraction& dump

KeV

few GeV

few GeVfew GeV

250-500 GeV

Designing a Linear Collider

Superconducting RF Main Linac


International Collaboration conclusions

• International Collaboration in High Energy Physics is more important than ever.

• The Pacific Region is capable of playing a major and increasing role as we enter the coming era.

• The Mission of Particle Physics is expanding, to embrace much of the forward looking science spearheaded in the Pacific Region over the past decade

• Asia will be full partners and perhaps hosts of the next great particle accelerator – the ILC

Documents

International Cooperation in High Energy Physics