david j. miller @ mumbai 15/12/03 ecfa for acfa 1 physics and detector studies in europe 1. where...

1David J. Miller @ Mumbai 15/12/03

ECFA for ACFA

Physics and Detector Studiesin Europe

1. Where we’ve been

2. Goals of ECFA StudyInternational

Detector design etc.

Machine Detector Interface

Physics Case

3. Conclusions.A couple of examplesfrom Higgs studies

The BDIR Group- The MATRIX- The mask- A crossing angle for TESLA?

Kalmus report


ECFA for ACFA Where we’ve been

Began in 1990, before first LCWS in Saariselka. series of workshops led by Ron Settles and Peter Zerwas

Then the ECFA/DESY Studies – wrote the Physicsand Detectors volumes of the TESLA TDR, Spring 1991

Extended ECFA/DESY Study, until Amsterdam, Spring ’03 Ron editing proceedings

ECFA Study had first workshop at Montpellier November 2003


ECFA for ACFA

Goals of the ECFA Study

International-------------- - to contribute to the development of a Global Linear Collider programme by encouraging international collaboration on the physics case, on detector R&D and on the machine-detector interface.

- to participate in the international LCWS workshops (the Saariselka series; PARIS NEXT, April 19-23 2004).

- to explore ways of co-ordinating and perhaps integrating the regional and worldwide workshop series.


ECFA for ACFA The Global LC Lab.

The European Linear Collider Steering Group askedGeorge Kalmus to chair a high level committeeon the possible governance of a World LC Lab.

Reported summer 2003. See:-

http://committees.web.cern.ch/Committees/ECFA/Cern03Kalmus.pdf

or slides http://committees.web.cern.ch/Committees/ECFA/Cern03KalmusReport.pdf%20

Lots of suggestions on governance, management and financing. Summarised in the two following slides.

N.B. This is not “Europe’s policy” on the LC. It is a set of suggestions.An agreed policy will not exist until Governments produce one.The ECFA chair warns us not take statements from any individualsas the policy.


ECFA for ACFA

Kalmus panel


ECFA for ACFA

ALMA is a radiotelescopearray.

ITER is thefusion torus.

GLCP is theGlobal LinearCollider Project.The Kalmusrecommendationsare summarisedin the last column.

Kalmus panel


ECFA for ACFA

Detector design, R&D, Simulation------------------------------------- - to design, build and test detector prototypes (with inter-regional collaboration).

- to maintain the detector design, and critically review its performance on all important physics channels.

- to build up a modern simulation framework (both for detector and physics studies) sharing resources with the other regions whenever possible.

- to prepare all tools necessary for a "simulated data challenge“.



ECFA for ACFA

Machine-Detector Interface-------------------------------- - to study the impact of realistic beams and the associated backgrounds on the detector.

- when the linac technology and crossing angle choice are made, to update all designs to match.

- to interact with the designers of the beam delivery system, ensuring that physics goals can be achieved.

- to participate in planning and R&D for polarimetry, beam energy measurement, beam monitoring, luminosity measurement.

- to study the special requirements of the gamma-gamma, e-gamma and GigaZ options.



ECFA for ACFA

Beam Delivery and Interaction Region(new name for MDI working group)

Growing activity, with many particle physicists.

* UK putting >£7.2 million into BDS design study including laserwire, feedback, beam monitoring, survey

* DESY Zeuthen leading R&D collab’n on small angle calorimeters and masking.

* Crossing angle is urgent.

* Philip Bambade’s “jobs to do” Matrix.


ECFA for ACFA MATRIX reloaded

• Identified 30 tasks for the BDIR group, assigned priorities and some names

Great Opportunities !

Comment for Mumbai ACFA: Europe cannot do all of these jobs; they‘ll have to be shared. See MATRIX at http://www-flc.desy.de/talks-public/bdir/BDIRprojects.html


ECFA for ACFA Karsten Buesser on the

Mask

TDR version• Shielding of the detector from direct and backscatterd beam induced

backgrounds?• Provide instrumentation for luminosity measurement, fast feedback

system and hermeticity?


ECFA for ACFA

TDR Mask Problems

• Mask tips are inside the tracking system• LAT has a conical surface

– Envisaged precision in the luminosity measurement using Bhabha scattering (ΔL/L ≈ 10-4) will be extremely challenging

• Quadrupoles are inside the detector solenoid

Challenges • New optical design with l*>4m.• Crossing angle or not ?

First try (Achim Stahl)

• Try to find, for minimal l*, a mask design with a flat LAT

geometry (in the head-on collision scheme)

Karsten Buesser


ECFA for ACFA

Proposed Design for l* ≥ 4.1m

Achim Stahl (presented in Amsterdam)Achim and I (DJM) prefer

“LUMICAL”(for LAT)~30<<100mr;primarily for L measurement.

“BEAMCAL” (for LCal)~5<<30mr;primarily forbeam monitoring(+tag +veto).


ECFA for ACFA New Mask Design

Advantages

• Flat LAT geometry

• LAT is behind ECAL, no scattering of particles off the LAT edge into the ECAL

• Mask moved out of the tracking system

• Vacuum situation much better

Questions

• How to open the detector ?

• What is the background situation ?

• What is the performance of the LAT/LCAL (Lumical/Beamcal)?Karsten Buesser


ECFA for ACFA Crossing angle makes a difference

NLC masking (S detector)


ECFA for ACFA

NLC Masking


ECFA for ACFA

Extraction Line IssuesNick Walker at Montpellier

To cross, or not to cross,

That is The Question


ECFA for ACFA

Spent beam extraction

horizontal

vertical

0-120 m 100-250 mNick Walker


ECFA for ACFA

Beamstrahlung Extraction

Nick Walker


ECFA for ACFA


Nick Walker


ECFA for ACFA


Nick WalkerIndicated power loss is for perfect design beam only!


ECFA for ACFA

Beamstrahlung loss on septum increases drastically (few W several kW) under (realistically) non-perfect collision conditions (A. Seryi, SLAC)

May be partially cured by increasing separator deflection angle – impact on FFS and extraction line (length!)?

Separator issues: sparking? Bunch-to-bunch (10-6) and pulse to pulse (>10-5) stability?

Typical bunch train, fbk on

1 kW

Nick Walker


ECFA for ACFA

(Large) Crossing Angle Concerns

• 20 mrad angle will need new final doublet design– NLC currently has PM– Compact s.c. quads possible (R&D needed)

• Crab-crossing required• More complicated IR• Impact on physics capabilities

– NLC says not!

• Civil engineering (cost!) implications

Nick Walker


ECFA for ACFA

300r vertical x-angle solution

R. Brinkmann

4m×300r=1.2mm

• shines BS away from septum blade and

• away from incoming beam @ BS dump

• needs quadruplet instead of doublet to obtain spent beam bandwidth

• crab-crossing needed but not so bad as that needed for 20mr horizontal crossing angle

• much optics and tracking work to do!! Nick Walker


ECFA for ACFA

Decision needed on X-anglefor cold machine

Phone-in meeting at Zeuthen, 19 Januaryorganised by Philip Bambade, agenda athttp://www-flc.desy.de/talks-public/bdir/meeting190104.html

Input on Physics (SUSY veto etc.)and machine aspects.

SLAC people will participate.

Please stay up all night and join in!

Aim to clarify issues before LCWS in Paris.


ECFA for ACFA

Physics Case-------------- - to co-operate with LHC colleagues to develop and present the arguments for concurrent running of LC and LHC.

- to explore the connections between the LC physics programme and cosmology.

- before the linac technology choice is made, to explore any differences between the physics capabilities of the candidate technologies.

- to continue to upgrade feasibility studies on important physics channels, with more realistic beam, background and detector simulation

Goals of the ECFA Study, continued


ECFA for ACFA

I only show a few slides out of a longtalk!


ECFA for ACFA

Kuhl


ECFA for ACFA


ECFA for ACFA

Arnaud Gay


ECFA for ACFA Results

Arnaud Gay


ECFA for ACFA

Arnaud Gay

NEW


ECFA for ACFA

Physics Case - continued

- to study quantitatively the potential systematic limitations on measurements and look for ways around them.

- to quantify the physics benefits from options to upgrade or vary the LC programme: from the energy upgrade, from the e- e-, e- and options, from the Giga Z option, from e+ polarisation, from narrower beam energy spread, from better polarimetry and spectrometry.

- to continue improving the precision of Standard Model and Supersymmetric predictions, to match the expected precision of experimental measurements with the LC.

- to continue to investigate new theoretical ideas, both strategic and methodological.

- to continue development of Monte Carlo generators suitable for LC physics.



ECFA for ACFA

Conclusions

1. There’s a lot to do – and we’reall in it together, Worldwide.

2. We look forward to seeing you in Paris in the Spring.

david j. miller @ mumbai 15/12/03 ecfa for acfa 1 physics and detector studies in europe 1. where...

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