The TESLA Status and the World Situation - LCUK Meeting Oxford, 29 January 2004 Technology World Situation Albrecht Wagner DESY and Hamburg ...
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The TESLA Status and the World Situation
LCUK Meeting
Oxford, 29 January 2004
• Technology
• World Situation
Albrecht Wagner
DESY and Hamburg University
Albrecht Wagner, Oxford 290104 1
The Scientific Case
for a LC
A world-wide consensus has formed for a baseline LC project in
which positrons collide with electrons at energies up to 500 GeV,
with luminosity above 1034 cm-2s-1.
The energy should be upgradable to about 1 TeV.
Above this firm baseline, several options are envisioned whose
priority will depend upon the nature of the discoveries made at
the LHC and in the initial LC operation.
The consensus document has been signed by > 2030 scientists
from all around the world.
http://www-flc.desy.de/lcsurvey/
Substantial overlap in running with LHC recommended
Albrecht Wagner, Oxford 290104 2
Relation of Hadron Collider and Linear Collider
1. Since the LC will start after the start of LHC, it must add
significant amount of information. This is the case!
2. Neither LC nor HC’s can draw the whole picture alone. A LC will
• add new discoveries and
• precision of LC will be essential for a better understanding of the
underlying physics.
3. There are probably pieces which can only be explored by the LHC
due to the higher mass reach. Joint interpretation of the results
will improve the overall picture
4. Overlapping running of both machines will further increase the
potential of both machines and might be mandatory, depending on
the physics scenario realized
Albrecht Wagner, Oxford 290104 3
SUSY ‘discovery’ could be simple
at LHC
…for squark masses < ~2 TeV
q DISCOVERY
q
χ02
Z
χ01
SUSY
SPECTROSCOPY?
require e.g. ETmiss>300 GeV and
four jets for m(squark) = 900 GeV
Albrecht Wagner, Oxford 290104 © Klaus Desch 4
Exclusive Reconstruction really difficult
typical SUSY diagram
at LHC
Albrecht Wagner, Oxford 290104 © Klaus Desch 5
Summary LHC/LC Study
First round of LHC/LC studies almost completed
• SUSY (as an example for a scenario with very rich new
phenomena) greatly benefits from synergy of LHC and LC analyses
• The studies show in a quantitative manner that joint analyses will
improve the knowledge about SUSY (mass measurements,
extraction of couplings/mixing angles, extrapolation to higher
scales)
• Some very clear advantages of simultaneous running became clear
(hopefully more to come): LC prediction of (possibly marginal) LHC
signals (call for higher LHC lumi, improved experimental techniques
etc)
Albrecht Wagner, Oxford 290104 © Klaus Desch 6
J. Ellis at al., hep-ph/0306219 Discovery vs Energy
Numbers of MSSM
particles detectable at
various accelerators in
benchmark scenarios:
Capabilities of the LHC
and of LCs are largely
complementary.
Mass and coupling
measurements at LC
usually much cleaner,
more precise than at
HC, where it is not
How many of the lower lying mass states known how to
does one need to discover in order to distinguish the light
establish the SUSY breaking mechanism? squark flavours.”
Albrecht Wagner, Oxford 290104 7
An Analogy: What precision does for you ... Albrecht Wagner, Oxford 290104 8
LC conceptual scheme
Final Focus
Demagnify and collide
beams Main Linac
Accelerate beam
Bunch Compressor to IP energy
without spoiling
Reduce s z to eliminate
DR emittance
hourglass effect at IP
Damping Ring
Reduce transverse phase space
(emittance) so smaller
transverse IP size achievable
Positron Target
Electron Gun Use electrons or photons to
pair-produce positrons
Deliver stable beam
current
Albrecht Wagner, Oxford 290104 9
Proof of principle: SLC
IP Beam Size vs Time
10 10
9 9
8 8
σX ∗ σy
7 7
Beam Size (microns)
σ x ∗σ y (microns )
2
6 6
New Territory in Accelerator Design and 5 5
Operation
4
SLC Design 4
• Sophisticated on-line modeling of non-linear (σx ∗ σy)
σX
physics. 3 3
σY
• Techniques expanded from trajectory to 2 2
emittance corrections, and from hands-on to 1 1
fully automated control.
0 0
1985 1990 1991 1992 1993 1994 1996 1998
Year
Albrecht Wagner, Oxford 290104 10The Challenges
Luminosity:
• high charge density (1010), > 10,000
bunches/s
• very small vertical emittance (damping
rings, linac)
• tiny beam size (5*500 nm) (final foc.)
Energy:
• high accelerating gradient
© R. Palmer SLC TESLA
Energy Ecm 100 500 (→ ~1000) GeV
Beam Power 0.04 ~10 MW
Spot size IP 500 (~50§) ~5 nm
Luminosity 3⋅10-4 3 1034 cm-2 s-1
Albrecht Wagner, Oxford 290104 11Key Challenges for High Gradient
L-band Superconducting Cavities
M. Tigner LC2003
Albrecht Wagner, Oxford 290104 12The TESLA Collaboration
• The TESLA Collaboration:
-at present 55 Institutes in 12
countries
These institutes have contributed
through hardware, manpower, and
ideas to the facility and share the
know-how concerning the
construction and operation of the
Sc linac
Albrecht Wagner, Oxford 290104 131 Hz measurement:
• individual cavity measurements Recent results in module # 5
• detuning of cavities at limit (#8 and #6)
• limitation for cavities #1-#5,#7: no time for detailed test, power limited, quench limit of
next cavity close
5 Hz measurement:
• full module test
• all cavities supplied with the same power
• limitation: quench in cavity #8
Albrecht Wagner, Oxford 290104 14TESLA 800 Performances with EP
EP (Electro-Polishing) developed at KEK by Kenji Saito (originally by Siemens)
Coordinated R&D effort: DESY, KEK, CERN and Saclay
1011
1E+11
9-cell EP cavities from
3rd Production 3rd production Cavities
- electro-polished
EP at Nomura Plating (Japan) by KEK AC72 ep
AC73 ep
1400 °C heat treatment AC76 ep
AC78 ep
10
Q1E+10
0 10
AC76: just 800 °C annealing
TESLA 800 specs:
35 MV/m @ Q0 = 5 × 109
Vertical CW tests of naked cavitis
109
1E+09
0 10 20 30 40
Eacc [MV/m]
Albrecht Wagner, Oxford 290104 15Calib.Measurement HERA plant
High Power Test of a
complete EP nine-cell cavity
Power/kW
• 1/8th of a TESLA cryomodule
Eacc/MV/m
• 5 Hz, 500 ms fill, 800 ms flat-top
• 33-> >35 MV/m
with no interruption related to
cavity-coupler-klystron for more
than 1000 hours
• No field emission
Albrecht Wagner, Oxford 290104 16High Gradients
Very important for choice of technology
5 cavities successfully
tested
Albrecht Wagner, Oxford 290104 17Recent results on AC70
EP at the new DESY plan 800°C annealing 120°C Backing
• Few nΩ residual resistance
• Negligible Field Emission
TESLA 800 specs:
35 MV/m @ Q0 = 5 × 109
Albrecht Wagner, Oxford 290104 18Important results for
TESLA LC
EP & 120°C backing are the key steps of the recipe
Field Emission and Q-drop cured
• Maximum field is still slowly improving
• Negligible Field Emission detected, that is
negligible dark current expected at this field level
• Cavity can be operated close to its quench limit
• Induced quenches are not affecting cavity performances
Albrecht Wagner, Oxford 290104 19Beam Sizes © M. Tigner Albrecht Wagner, Oxford 290104 20
Damping Ring
Low emittance
ATF Damping
Ring at KEK
“Laser Wire”
Albrecht Wagner, Oxford 290104 21TESLA RF Unit
1 klystron for 3 accelerating modules, 12 nine-cell cavities each
vector
modulator MBK Klystron
circulator
DAC
DAC
Mechanical tuner
(frequency adj.)
stub tuner (phase & Qext)
Low and piezo-electric tuner
(Lorentz force compensation)
Level coaxial coupler
RF
System
cavity #1 cavity #12
pickup signal
vector sum
ADC
ADC
accelerator module 1 of 3
vector
demodulator
Albrecht Wagner, Oxford 290104 22TESLA Multi Beam
Klystrons
1) Three Thales TH1801 Multi Beam 2) Indipendent beam design proposed
Klystrons produced and tested and built by CPI. Tests from February.
Achieved efficiency 65%
RF pulse width 1.5 ms
Repetition rate 5 Hz
Operation experience > 5000 h
10% of operation time at full spec‘s
3) A new design proposed by Toshiba looks robust and should reach 75% efficiency
First prototype tests expected on April this year
Albrecht Wagner, Oxford 290104 23Albrecht Wagner, Oxford 290104 24
Status of TTF and the VUV-FEL
RF gun M2 M3 M4 M5 M6 M7
M1
undulator
s
bunch bunch collimator FEL
Laser compressor compressor bypass
experimenta
4 MeV 150 MeV 450 MeV 1000 MeV l area
250 m
Albrecht Wagner, Oxford 290104 25Status
Major task during last 4 months:
• installation into tunnel of 260 m beam line, (almost) all new
• many different and advanced components (90 % completed )
Entire vacuum will be closed mid Febr. 04
Next steps:
1. Injector tests during first half of 2004
2. full commissioning during second half of 2004
Albrecht Wagner, Oxford 290104 26The VUV-FEL: A Test-bed for XFEL Issues
A major emphasis in the up-grade from 250 MeV to 1 GeV has
been put on beam diagnostics to learn as much as possible about
all critical parameters of the electron and photon beams:
- Standard beam position monitors
- Optical Transition radiation monitors
(beam profile)
- Wire scanner stations
- Longitudinal bunch shape measurement
- Interferometer measurements (bunch length)
- Electro-optical sampling
- Emittance and phase measurement
Many other issues, such as operation stability and
experimentation can also be studied at the VUV-FEL
It will also be a test-bed for new concepts
Albrecht Wagner, Oxford 290104 27Transverse Emittance Measurement @ PITZ
-
1.7
1.5
Design goal reached
Albrecht Wagner, Oxford 290104 28planned LC XFEL Site at DESY Site chosen to make maximum use of DESY infrastructure to avoid interference XFEL/LC Albrecht Wagner, Oxford 290104 29
XFEL Project Group: 38 work packages
Note synergy!
accelerator modules
module test /
magnets / cryogenics
linac components
(injector, bunch
compressors,
diagnostics, dumps)
Photons
FEL concepts
Controls / Operability
Infrastructure
(site, civil
construction, survey,
tunnel layout,
utilities)
Safety
Organisation
Albrecht Wagner, Oxford 290104 30Strategy : What has Happened since 2001?
• ACFA, ECFA, HEPAP scientific recommendations (2001)
• TESLA TDR in March 2001
• OECD Global Science Forum (2002 and continuing)
• German Science Council recommendations (Nov 2002)
• JLC Road Map in February 2003
• German Government decision
• International Technical Review (2003)
• ILCSC and regional steering groups
• Discussion among funding agencies
• Discussion in CERN Council about CERNs role in a LC
• WGs on organisational matters
• GAN workshops
• US 20 year outlook….
Albrecht Wagner, Oxford 290104 31LC Organisation Albrecht Wagner, Oxford 290104 32
Technology Choice
The International Linear Collider Steering Committee (ILCSC)
has selected twelve members of the International Technology
Recommendation Panel (ITRP):
Asia: Europe: North America:
G.S. Lee J-E Augustin J. Bagger
A. Masaike G. Bellettini B. Barish (Chair)
K. Oide G. Kalmus P. Grannis
H. Sugawara V. Soergel N. Holtkamp
First meeting end of January at RAL
Recommendation of one technology (NLC or TESLA)
before end of 2004
Albrecht Wagner, Oxford 290104 33ITRP Charge 1
http://www.fnal.gov/directorate/
icfa/International_ILCSC.html
Albrecht Wagner, Oxford 290104 34ITRP Charge 2 Albrecht Wagner, Oxford 290104 35
ITRP Charge 3
visit of ITRP to DESY is 5/6 April 2004
Albrecht Wagner, Oxford 290104 36R1: R&D Needed for a
Feasibility Demonstration
Review defines and ranks R&D
needed for choosing technology
Is a feasibility demonstration required?
Score Card
Albrecht Wagner, Oxford 290104 37R2 Comparison
TESLA NLC/JLC
• Test of complete main linac RF • Test of complete X-band main
sub-unit (as in TDR) with beam linac RF sub-unit (as described in
• Tests of several cryomodules baseline design) with beam
running at gradient 23.4 MV/m
for a prolonged period of time • Full test of KEK 75 MW 1.6µs
– quench rates, breakdowns, PPM klystron at 150/120 Hz
dark current
• Full test of SLAC induction
• One versus two tunnels
(reliability) modulator
• DR dynamic aperture
– wiggler end fields
– minimise injection losses
(Pinj=220kW)
• DR kicker development
• Head-on versus crossing angle
– extraction lines issues
Albrecht Wagner, Oxford 290104 38Common R2 Items
• Damping Rings
– Electron cloud effects
– fast ion instabilities
– Extraction kicker stability
– Tuning simulations
Common items • LET: Low Emittance Transport
related to all – Static tuning studies
designs – girder/cryomodule prototypes
to study stability (vibration)
– Critical beam instrumentation
• Reliability
– Detailed evaluation of critical
sub-systems reliability
Albrecht Wagner, Oxford 290104 39Political Situation
US
Mid Term Readiness for
construction
Germany: „The government is the first one to have announced to
be principally committed to participating in the project. “
UK: Substantial increase in R&D sending for LCs
Albrecht Wagner, Oxford 290104 40Draft Ministerial Statement Regarding the Importance of
International Co-operation on Large Accelerator-based
Projects in High-Energy Physics
Ministers expressed their appreciation for the work of the OECD
Global Science Forum Consultative Group on High-Energy
Physics. They welcomed the report from the Group and
commended the clarity and world-wide consensus they found
amongst the high-energy physics community in developing the
Roadmap for future large accelerator-based facilities.
In particular, the Ministers note several important points that
were articulated in the report:
• A roadmap that identifies four interdependent priorities for
global HEP facilities i) the exploitation of current frontier
facilities until contribution of these machines is surpassed, ii)
completion and full exploitation of the Large Hadron Collider at
CERN, iii) preparing for the development of a next-generation
electron-positron collider, and iv) the continued support for
appropriate R&D into novel accelerator designs. …….
Albrecht Wagner, Oxford 290104 41Draft Ministerial Statement Regarding the Importance of
International Co-operation on Large Accelerator-based
Projects in High-Energy Physics
• The need to have large, next-generation facilities funded,
designed, built, and operated as global-scale collaborations
with contribution from all countries that wish to participate.
• The need for strong international R&D collaboration and
studies of the organisational, legal, financial, and
administrative issues required to realize the next major
accelerator facility on the Consultative Group's Roadmap, a
next generation electron-positron collider with a significant
period of concurrent running with the LHC.
• The need to continue to educate, attract and train young
people in the fields of high-energy physics, astrophysics and
cosmology in the face of the increasingly competitive
environment where all areas of science, industry and
commerce are seeking to capture the imagination of the most
creative minds.
Albrecht Wagner, Oxford 290104 42Draft Ministerial Statement Regarding the Importance of
International Co-operation on Large Accelerator-based
Projects in High-Energy Physics
Ministers agreed that, given the complexity and long lead times
for decision making of major international projects, it is
important that consultations continue within the scientific
communities and, when it becomes appropriate, within
interested governmental communities in order to maximise the
advantages offered by global collaboration.
OECD Ministers will meet 29/30 January
Albrecht Wagner, Oxford 290104 43Meeting of Funding Agencies Meeting of Funding Agencies to discuss the status and funding prospects for a linear collider of 0.5 – 1TeV. 30 July 2003, London, UK Representatives from Canada (NSERC), CERN (President of Council and DG), France (CNRS), Germany (BMBF), Italy (INFN), UK (PPARC), and the US (DOE, NSF, OSTP). Recognised that scientific committees have established a need for future facilities of such a scale that an international forum of potential funding agencies/sponsors was needed. The group discussed the status of current funding for a linear collider (LC) and their perceptions of the prospects for the future. Next meeting in March 2004 Albrecht Wagner, Oxford 290104 44
2002: Worldwide Concensus on Next
Major HEP Facility
Statement by ICFAS chair, Jonathan Dorfan, to ITRP
on 27 January 2004
• In 2002, planning exercises in Europe (ECFA), Asia (ACFA) and the
US (HEPAP) resulted in an unanimous alignment of each region’s
highest priority goal, namely the construction of a 500 GeV
electron positron linear collider as a necessary physics companion
for the LHC
– ECFA, ACFA & HEPAP all endorsed this as an urgent need. All
regions strongly urged that the project be fully international
from the outset
Albrecht Wagner, Oxford 290104 45In 2004, The Community’s Worldwide
Commitment Remains Unchanged
The Chairs of ECFA, HEPAP and ACFA have this past week,
reasserted their regional support for the LC. In their words:
“I can confirm that all the conclusions of the Lorenzo Foa panel,
including that the next priority for a new machine for particle physics
should be a linear electron-positron collider with an initial energy of
at least 400 GeV, extendible up to about 1 TeV, remain the basis for
the policy currently being pursued by ECFA.” (Brian Foster)
“With the upcoming first meeting of the ITRP, I want to make it clear
that the highest priority in the U.S. HEP program is a high-energy,
high-luminosity electron-positron Linear Collider. Not only was this the
conclusion of the Long-Range Planning Subpanel that was unanimously
endorsed by HEPAP in 2002, but it subsequently was restated in the
2003 recommendations from HEPAP of the high-energy facilties to be
a part of the Department of Energy Office of Science twenty-year
facilities plan. “ (Fred Gilman)
Albrecht Wagner, Oxford 290104 46In 2004, The Community’s Worldwide
Commitment Remains Unchanged
“ACFA made two ACFA statements in the past on the International
Linear Collider Project, which should be a world-wide collaboration
in construction and operation.
At the Plenary ACFA meeting in October 2002 in Melbourne, ACFA
established ALCSC for promotion of the GLC project in Asia and
for close collaboration with other region's activities, especially with
ILCSC.
ACFA put the Linear Collider Project at the highest priority in
high-energy physics research for concurrent running with LHC.
Even though the concurrent LC operation is important for the
interaction of LHC/LC physics, we would also like to stress the
absolute importance of LC irrespective of LHC.” (Won Namkung)
• Any person or group that states their region’s priorities wrt LC as
otherwise, is out of synch with their community’s desires
Albrecht Wagner, Oxford 290104 47An exercise….. Possible Spending Profile for TESLA
TESLA material cost vs construction year
600
Injection
500 Beam Delivery
Million Euro
400 Auxiliary
Damping Rings
300
Infrastructure
200
RF System
100
Main LINAC Module
0 Civil Construction
1 2 3 4 5 6 7 8
Injection 2008
2 09
3 10
5 119 12
15 13
23 14
20 15
20
Beam Delivery 5 5 5 10 15 15 15 30
This is assuming
Auxiliary 5 5 a construction
10 10 10 time
20 of408 years.
24
Damping Rings 5 10 15 20 50 50 50 14
By parallel 5manufacturing
Infrastructure 10 30 30of components
60 70 65 this
65 construction time
can be shortend
RF System 15
10
30
40
to ~
40
80
6 years
100
100
100
200
100
250
100
250
100
200
Main LINAC Module
-> matches45turn
Civil Construction 100
on 180
and first
180
results
40 0
of0LHC0 before major
spending starts
Albrecht Wagner, Oxford 290104 48Next Milestones towards a
Global Linear Collider
2004 Selection of Collider Technology (warm or cold) and setting
up of an international project team with branches in
America, Asia and Europe
Continuation of discussion between funding agencies
Further studies of organisation structures
2005 Start of work of project teams (‚Pre GLC‘)
2006 Completion of the project layout including costing
2007 Decision in principle by governments to go ahead with LC
2015 Start of commissioning
Albrecht Wagner, Oxford 290104 49Global Design Organisation
WG of ILCSC, chaired by S. Ozaki, is preparing a design organisation
to move the global project forward as soon as the technology choice
has been made.
Discussion about structure and tasks are well advanced
Central Team
Team Region 1 Team Region 2 Team Region 3
Task:
Establish internationally agreed design, defining the basic layout of
facility and subsystems.
Complete technical design document incl. costing etc.
First presentation to ILCSC in February
Albrecht Wagner, Oxford 290104 50The Airbus Example Albrecht Wagner, Oxford 290104 51
Summary • The scientific case is as strong as ever. The complementarity with LHC is strong, so is the discovery potential of the LC • Broad support and enthusiasm in community (consensus paper, YPPs, ..) • Need to continue to impress politicians by steady progress (technical decision, joint global design, self-organisation,..) • Strength of field lies in ability to form consensus. We should be careful to maintain it. • We need to keep cost of the project within meaningful boundaries, e.g. LHC, ITER. This can be done. • We need to present a time line which allows politicians to react and us to keep the momentum going. • 2015 is a realistic target date for commissioning. To reach this we have to keep going at full speed. Albrecht Wagner, Oxford 290104 52
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