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DESY-Zeuthen

AMANDA (Antarctic Muon And Neutrino Detector Array)- observe high-energy (~ 1 TeV ) neutrinos from astro physical point sources- dark matter search- gamma ray bursts

APEmille:- APEmille is a versatile massive-parallel processor optimised for heavy duty numerical applications and scalable from 4 GigaFlops to 1 TeraFlops.- QCD calculations on the lattice → "theoretical" understanding of confinement?

... among many other activities:

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DESY’s Future: TESLA

There is unanimous agreement within the worldwide particle physics community that the next large accelerator to be built is a linear e

+

e

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collider which will complement the physics program carried out at the Large Hadron Collider (LHC at CERN)

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for example read recommendation from the U.S. HEPAP panel (Oct �01):

"We recommend that the highest priority of the U.S. program be a high-energy, high luminosity, elec-tron-positron linear collider, wherever it is built in the world. This facility is the next major step in the field and should be designed, built and operated as a fully international effort."

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DESY has a very well advanced proposal for such a machine based on superconducting cavities at DESY: TESLA (TeV Energy Superconducting Linear Accelerator)

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however there is worldwide competition from several labs around the world which are based on alternative technologies:

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U.S. NLC (Next Linear Collider)

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Japan JLC (Japanese Linear Collider)

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CERN CLIC (Compact Linear Collider, probably only the overnext step)

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there is also agreement that due to the complexity and amount of money imvolved only one such machine will be built in the world

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TESLA Physics Case

TESLA offers unique possibilities for precision studies of

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the Higgs mechanism

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Supersymmetry

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the Standard Model: electroweak precision measurements,

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W and top properties measurements, QCD, etc.

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and for the search for the unexpected.

The great experimental precision is a probe for new physics and allows predictions on an energy scale well beyond the reach of the accelerator.

Super Symmetry

Higgs Signal

Higgs Branching Ratios

Higgs-Couplings

ProductionTop-

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Project Overview

Superconducting Linear Collider with an Centre-of-Mass-Energgy Ecm=500-800 GeV with an Integrated Super Brilliant X-ray Free Electron Laser Facility

Technical Data- electron-positron collision energy 500 GeV (expandable to 800 GeV)- # of superconducting resonators: 20000- operating temperature of resonators -271 C - required alignment precision 0.5 mm- installed load 195 MVA- wavelength of X-ray radiation 5 to 0.05 nm

- luminosity 3.4 1034 cm-2s-1

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TESLA Technology

One of the key elements of TESLA are the superconducting cavities which have to have sufficient quality to reach 25 MV/m neccessary for 500 GeV.

Limitations of superconducting cavities are

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Intrinsic Limitation:

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Critical magnetic field of niobium

⇒

E

acc, max

= 50 - 55 MV/m

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Technical Limitations:

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Normalconducting defects due to inclusions

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very clean, defect-free niobium

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Field emission

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no particle contamination on the niobium surface

After many years of R&D it is already possible to reach the >40 MV/m needed for 800 GeV after very special treatment of single cell cavities. Fabrication techniques:

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electron beam welding

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hydro forming

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spinning

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XFEL and SASE

Characteristics of light:• pulse duration: 100 femto sec• wavelength: 1Å=0.1 nm• lateral coherence

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Applications for XFEL

Examples for questions from very different fields of science that will be addressed at such an XFELCan we ...

• take pictures of single macro-molecules?• see the dynamical behaviour of the electrons as they form

chemical bonds?• make a movie of a chemical reaction?• make realtime studies of the

formation of condensed matter?• make a movie of fast switching in

magnetic storage devices?• follow a viral infection in a cell at

high resolution?

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TESLA Test Facility

• TTF has already been in operation for ≈9000 h providing a very sound system- test of all essential components

• the free-electron SASE principle has been demonstrated at wavelengths of 80-180 nm.

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Outreach

DESY EXPO 2000

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