TheInternational
Linear Collider(ILC) – Status
and Dubna Siting
Grigori ShirkovDubna, July 26, 2006
МеждународныйЛинейныйКоллайдер
• Energy – need to reach at least 500 GeV CM as a start
• Luminosity – need to reach 10^34 level
Linear Collider – two main challenges
Luminosity & Beam Size
• frep * nb tends to be low in a linear collider
• The beam-beam tune shift limit is much looser in a linear collider than a storage rings achieve luminosity with spot size and bunch charge– Small spots mean small emittances and small betas:
x = sqrt (x x)
Dyx
repb HfNn
L
2
2
L frep [Hz] nb N [1010] x [mm] y [mm]
ILC 2x1034 5 3000 2 0.5 0.005
SLC 2x1030 120 1 4 1.5 0.5
LEP2 5x1031 10,000 8 30 240 4
PEP-II 1x1034 140,000 1700 6 155 4
Beam Parameters
• Requirements:– High luminosity – set by physics needs– Low backgrounds (small IP effects)– Forced to high beam power and small vertical spots
• Details of technology determine other limitations– Rf cavities and power sources 10 mA beam current– Damping rings beam emittances and number of bunches– Bunch compressors IP bunch length– Cryogenic systems duty cycle– Extensive cost optimization is required to balance systems
• Linear collider will push many technological and beam-physics limits – Need to have operational flexibility to overcome unexpected
problems
ILC Parameters
Parameter range established to allow for operational optimization
Schematic of the ILCe-(e+) source and delivery system
Damping Ring(s)
Ring(s) To Main Linac (RTML system)
Main Linac (ML)
Beam Delivery System (BDS)
Beam Dump (BD)
2nd stage ILC : 1 TeV
- extension of main linac
- moving of SR and BC
1st stage ILC : 500 GeV
room-temperature accelerating sect.
diagnostics section
standard ILC SCRF modules
Guns
sub-harmonic bunchers + solenoids
laser
Laser requirements:pulse energy: > 5 uJpulse length: ~ 2 ns# pulses/train: 2820Intensity jitter: < 5 % (rms)pulse spacing: 337 nsrep. rate: 5 Hzwavelength: 750-850 nm
DC gun:120 keV HV
Room temperature linac:Allows external focusing by solenoidsSame as e+ capture linac
Photocathodes:GaAs/GaAsP strained super-lattice
ILC Gun Schematic View
ParameterPulse length 0.9ms
Pulse reputation 5Hz
# of electrons in a micro bunch 2.00E+10# of micro bunches in a pulse 2800(5600)
Bunch separation 308(154)ns
Bunch charge 3.2(1.6)nC
Micro bunch length at source 0.5-2ns
Peak current 12.8A(0.5ns)Electron Polarization 80%
ILC Gun Beam Specifications
• Polarized electrons are produced by injecting circularly polarized photons(sz=±1) on NEA GaAs cathode.
ILC Gun Multi Bunch Laser
Output pulse train Output pulse train of the OPCPAof the OPCPA
► OPCPA (Optical Parmetric Chirped Pulse OPCPA (Optical Parmetric Chirped Pulse Amplification) system generates trains with a Amplification) system generates trains with a wide range of pulse length, 150 fs .. 20 ps wide range of pulse length, 150 fs .. 20 ps (FWHM)(FWHM)
► Pulse energy: EPulse energy: Emicromicro = 50 ~ 100 uJ = 50 ~ 100 uJ E Etraintrain = up to 80 mJ = up to 80 mJ
► Available wavelength: = 790 ~ 830 nmAvailable wavelength: = 790 ~ 830 nm
► Pulse train: up to 0.9msPulse train: up to 0.9ms
up to 900 us
= 12 ps(FWHM)
= 523 nm
synchronizedNd:YLF Burst-Mode laser
pumping the OPA
= 150 fs (FWHM)Emicro = 50...100 mJ
@ f= 1 MHz
picosecond-pulseoutput channel:
pulse trains, 800 ms long
= 15 ps 100 fs
G > 5 000primary
synchronization loop
master clockf = 1.3 GHz
mixer1.3 GHz
photodiode
Piezo
three-crystalOPA
outputpulse trains800 ms long, = 790 ...
830 nm
gratingcompressorgrating stretcherTi:Sa oscillator
G ~ 20
I. Will, H. Redlin, MBI Berlin
Damping Rings• Damping rings have more accelerator physics than the rest of the collider• Required to:
1. Damp beam emittances and incoming transients
2. Provide a stable platform for downstream systems
3. Have excellent availability ~99% (best of 3rd generation SRS)
• Mixed experience with SLC damping rings:– Referred to as the “The source of all Evil”– Collective instabilities; Dynamic aperture; Stability
• Damping ring designs based on KEK ATF, 3rd generation SRS, and high luminosity factories– Experimental results provide confidence in design
Issues in the Damping Rings• Emittance tuning and error correction
– Orbit correction and component stabilization• Injection/extraction of individual bunches
– Kicker rise/fall time – very large rings to store 3000 bunches• Dynamic aperture
– Long wigglers needed if the ring is too big• Single-bunch intensity
– Tune shift by self-Coulomb force (space charge)• Instabilities (mainly average current)
– Electron cloud instability– Fast ion instability– Classical collective instabilities
• Rings operate in a new regime with fast damping and very small beam emittances
An aside: the damping wiggler• The damping time in a storage ring depends on the rate of energy
loss of the particles through synchrotron radiation. In the damping rings, the rate of energy loss can be enhanced by insertion of a long wiggler, consisting of short (~ 10 cm) sections of dipole field with alternating polarity.
y
xz
By = Bw sin(kzz)
The magnetic field in thewiggler can be approximated by:
Main Linac Design• Baseline Configuration Document (BCD) distilled from
Snowmass Working Group recommendations in August
2005.
• Major differences from 2001 Tesla TDR 500 GeV Design.
– Higher gradient (31.5 MV/m instead of 23.4 MV/m) for cost
savings.
– Two tunnels (service and beam) instead of one for improved
availability.
• The Linac Area Group of the Global Design Effort (GDE)
is continuing to evolve design.
Superconducting RF Acceleration technology
- Nano-meter size beam handling technology
Laser wire system
Technical Challenges at the ILC
電場
( 陽 ) 電子
Acceleration
Electric Field
Electron (positron)
OriginalCornellN = 5
High Gradient
N =7
LowLossN =7
TESLA
N=9
SNSß=0.61
N=6
SNSß=0.81
N=6
RIAß=0.47
N=6
RHIC
N=5
year 1982 2001 2002 1992 2000 2000 2003 2003
aff 1489 2592 3288 4091 3883 2924 5040 850
● Field flatness vs. N
Multi-cell Structures and Weakly Coupled Structures Cavities
cc
2
ff k
Na
i
i
cc
2
i
iff
i
i
f
f
k
N
f
fa
A
A
Field flatness factor
For the TESLA cavities: field flatness is better than 95 %
‣ Made with solid, pure niobium – it has the highest Critical
Temperature (Tc = 9.2 K) and Thermodynamic Critical Field
(Bc ~ 1800 Gauss) of all metals.
‣ Nb sheets are deep-drawn to make cups, which are e-beam
welded to form cavities.
‣ Cavity limited to ~ 9 cells (~ 1 m Long) to reduce trapped
modes, input coupler power and sensitivity to frequency
errors.
‣ Iris radius (a) of 35 mm chosen in tradeoff for low surface
fields, low rf losses (~ a), large mode spacing (~ a3 ), small
wakes (~ a-3.5 ).
1.3 GHz TESLA
Cavities
Cryomodule with four 9 cell cavities
13 m
Cryomodule DesignRelative to the TTF cryomodules
– Continue with 8 cavities per cryomodule based on experience and minimal cost savings if number increased (12 in TDR).
– Move quad / corrector / bpm package to center (from end) to improve stability.
– Increase some of cryogenic pipe sizes (similar to that proposed for the XFEL).
– Decrease cavity separation from 344 mm to 283 mm as proposed in the TDR.
Niobium:Electron Beam Melting• High Purity Niobium(RRR>250) is made by multiple electron beam
melting steps under good vacuum, resulting in elimination of volatile impurities
• There are several companies, which can produce RRR niobium in larger quantities:
Wah Chang (USA), Cabot (USA), W.C.Heraeus (Germany), Tokyo Denkai(Japan), Ningxia (China), CBMM (Brasil)
CBMM deposit in Araxa, Brasil EBM furnace at Tokyo DenkaiEBM Ingots at CBMM
Fabrication(3)
Cavity Tests on Mono-cells
- dedicated nozzle system for cavity cleaning developed [L.Lilje, CARE Meeting Nov. 2004, DESY]
Fabrication• Hydro forming (W.Singer,DESY) Spinning
(V.Palmieri,INFN Legnaro)
Beam Delivery System challenges
• Focus the beam to size of about 500 * 5 nm at IP • Provide acceptable detector backgrounds
– collimate beam halo
• Monitor the luminosity spectrum and polarization– diagnostics both upstream and downstream of IP is desired
• Measure incoming beam properties to allow tuning of the machine
• Keep the beams in collision & maintain small beam sizes – fast intra-train and slow inter-train feedback
• Protect detector and beamline components against errant beams
• Extract disrupted beams and safely transport to beam dumps• Minimize cost & ensure Conventional Facilities constructability
BDS
BDS: from end of linac to IP, to dumps
Beam Delivery System• Requirements:
– Focus beams down to very small spot sizes– Collect out-going disrupted beam and transport to the dump– Collimate the incoming beams to limit beam halo– Provide diagnostics and optimize the system and determine the
luminosity spectrum for the detector– Switch between IPs
How to get Luminosity
• To increase probability of direct e+e- collisions (luminosity) and birth of new particles, beam sizes at IP must be very small
• E.g., ILC beam sizes just before collision (500GeV CM): 500 * 5 * 300000 nanometers (x y z)
Vertical size is smallest
Dyx
brep HNnf
L
2
4
5
300000500
Modulators (115 kV, 135 A, 1.5 ms, 5 Hz)
Pulse Transformer Style
(~ 2 m Long)
To generate pulse, an array of capacitors is slowly charged in parallel and then discharged in series using IGBT switches.
Will test full prototype in 2006
KlystronsBaseline: 10 MW Multi-Beam Klystrons (MBKs) with ~ 65%
Efficiency: Being Developed by Three Tube Companies in Collaboration with DESY
Thales CPI Toshiba
Beam dump for 18MW beam• Water vortex
• Window, 1mm thin, ~30cm diameter hemisphere
• Raster beam with dipole coils to avoid water boiling
• Deal with H, O, catalytic recombination
• etc.
The Big Picture: ILC Site Power ~ 330MW
Sub-Systems 60MW
Main Linacs 140MW
Cryogenics:
50MW
RF: 90MW
65%
78%
60%
Beam 22MW
Injectors
Damping rings
Auxiliaries
BDS
DefinitionsICFA - International Committee for Future Accelerators
FALC - Funding Agencies for the Linear Collider
ILCSC - International Linear Collider Steering Committee
GDE - Global Design Effort
RDB - Research and Development Board
CCB - Change Control Board
DCB - Design Cost Board
CFS - Conventional Facilities and Siting
BCD - Baseline Configuration Document
RDR - Reference Design Report
TDR - Technical Design Report
WBS - Work Breakdown Structure
International OrganizationInternational Organization
Global Design EffortGlobal Design Effort
International Linear Collider Timeline 2005 2006 2007 2008 2009 2010
Global Design Effort Project
Baseline configuration
Reference Design
ILC R&D Program
Technical Design
Expression of Interest to Host
International Mgmt
THE 50 KM LINETHE 50 KM LINE
Longitudinal Section
EUROPEAN SAMPLE SITE - CERNEUROPEAN SAMPLE SITE - CERN
EUROPEAN SAMPLE SITE - DESYEUROPEAN SAMPLE SITE - DESY
Longitudinal Section
ASIAN SAMPLE SITEASIAN SAMPLE SITE
Longitudinal Section
AMERICAS SAMPLE SITEAMERICAS SAMPLE SITE
Longitudinal Section
For baseline, developing deep underground (~100 m) layout with 4-5 m diameter tunnels spaced by 5 m.
ILC Tunnel Layout
MAIN LINAC BEAM TUNNEL VENTILATION
Normal airflow same as Service tunnel
Smoke airflow (TBD) Assume 2X = 38,000cfm
ODH airflow (TBD).
Construction Airflow (not included)
Thermal load Airflow (Not included). Minimal load to air
MAIN LINAC SERVICE TUNNEL VENTILATION
Normal airflow for 1 mile per hour speed= 19,000 cfm dry 100% outdoor air per tunnel = 0.3 airchange per hour at 5 meter diamater tunnel. Airflow increase per CO2 sensor.
Smoke airflow (TBD) Assume 2X = 38,000cfm (placeholder)
ODH airflow (NONE). Service tunnel to be separated from Cryo cavern
Construction Airflow (not included)
Thermal load Airflow (Not included). Heat load to air will be handled by separate chilled water fancoils (see sketch)
OVERALL SCHEMATIC LAYOUTOVERALL SCHEMATIC LAYOUT
EXTENT OF CONSTRUCTIONEXTENT OF CONSTRUCTION
• Main Accelerator Enclosures - 475,000 mMain Accelerator Enclosures - 475,000 m33
• Main Accelerator Support Enclosures - 475,000 mMain Accelerator Support Enclosures - 475,000 m33
• 2 Damping Ring Enclosures - 210,000 m2 Damping Ring Enclosures - 210,000 m33
• 12 Access Shafts - 70,000 m12 Access Shafts - 70,000 m33
• Beam Delivery Enclosures - 160,000 mBeam Delivery Enclosures - 160,000 m33
• 2 Interaction Halls - 800,000 m2 Interaction Halls - 800,000 m33
• Additional Support and Transport Enclosures - 300,000 mAdditional Support and Transport Enclosures - 300,000 m33
• Surface Facilities - 85,000 mSurface Facilities - 85,000 m22
Side View of ShieldedSide View of ShieldedTunnel Boring MachineTunnel Boring Machine-W. Bialowans-W. Bialowans
Cutting Face of ModernCutting Face of ModernTunnel Boring MachinesTunnel Boring Machines-W. Bialowans-W. Bialowans
Interaction Hall SchematicsInteraction Hall Schematics
Cryogenic PlantsCryogenic Plants
Water Processing PlantsWater Processing Plants
Electrical SubstationsElectrical Substations
ILC siting and conventional facilities in Dubna region
Joint Institute for Nuclear Research
Dubna, RussiaInternational Intergovernmental Organization
18 member states; 4 associate members
- The international intergovernmental organization Joint Institute for Nuclear Research -
prototype of ILC host institution;
- Experienced personal of JINR in accelerators, cryogenics, power supplies and etc.
- Infrastructure and workshops of JINR on the first stage of ILC project realization;
- The town Dubna provides with all the necessary means of transport to deliver all kinds of
the equipment of the accelerator itself and its technological systems: highways, railways,
waterways (through Volga river to Black sea, Baltic sea, Polar ocean);
- The international airport «Sheremetyevo» is situated at the distance of 100 km from
Dubna (1.5 hours by highway);
- Developed Internet and satellite communication;
- A Special Economic Zone (industrial+scientific) in the Dubna region (Edict of Russian
Government, Dec. 2005), provides unique conditions in taxes and custom regulations;
- A good position in the European region;
- A positive reaction received in preliminary discussions with the interested
governmental persons and organizations in Russia.
Advantages of Location
Russian Satellite Communications Center
0 km
10 km
20 km
30 km
40 km
500 kV power line
Volga river
Dubna city
The area is thinly populated, the path of the accelerator traverses 2 small
settlements and a railway with light traffic between Taldom and Kimry.
Possible “line” crosses only the railway to Savelovo (of low utilization) and
the River Hotcha with a very small flow rate.
The climate is temperate-continental. The mean temperature in January
is –10.7С. The mean temperature in July is +17.8С. The mean annual
rainfall is 783 mm. The mean wind speed is 3.2 m/s. Strong winds (15
m/s) blow only 8 days/year. According to the climatic parameters, the
territory of Dubna is considered to be comfortable.
Area and Climate
Power and energetics
The northern part of Moscow region and the neighboring regions have a developed system of objects of generation and transmission of electrical energy. There are first-rate generating stations: the Konakovo EPS (electric power station, ~30 km from Dubna) and the Udomlia APP (atomic power plant, ~100 km from Dubna).
Two trunk transmission lines with the voltage 220 kV and 500 kV pass through the territory of Dubna.
The investigation of possibilities of the power supply for the accelerator and its infrastructure with the total power up to 300 MW gives the following variant:Construction of the power line-220 kV, 35÷40 km long, directly from the center of generation – the Konakovo EPS to the Central Experimental Zone of the accelerator with a head step-down substations 220/110 kV.
It will require the investment in larger amount but the cost of power obtained directly from the centers of generation will be lower for 40÷50 % (from 0.05$ per 1kWh down to 0.02-0.03 $ per 1kWh in prices of 2006).
The area of the proposed location of the accelerator is situated
within the Upper Volga lowland. The characteristic feature of this
territory is the uniformity, monolithic character of the surface. The
existing rises of the relief in the form of single hills and ridges have
smoothed shapes, soft outlines and small excesses. The territory of
the area is waterlogged. The absolute marks of the surface range
from 125 to 135 m with regard to the level of the Baltic Sea.
The difference of surface marks is in the range of 10 m only on
the base of 50 km.
Relief
The area of the proposed location of the accelerator is situated within the Russian
plate – a part of the Eastern European ancient platform – a stable, steady structural
element of the earth’s crust.
The Russian plate, like all the other plates, has a well-defined double-tier
structure. The lower tier or structural floor is formed by the ancient – lower
Proterozoic and Archaean strata of metamorphic and abyssal rocks, which are more
than 1.7 billion of years old. All these strata are welded into a single tough body –
the foundation of the platform. The area of the ILC accelerator is located in the
southern part of a very gently sloping saucer-shaped structure – the Moscovian
syneclise.
Alluvial deposits i.e. fine water-saturated sands, 1-5 m of thickness. Below one
can find semisolid drift clay of the Moscovian glaciation with exception of detritus
and igneous rocks. The thickness of moraine deposits is 30-40 m.
Geology
The ILC linear accelerator is proposed to be placed in the drift clay at the depth of 20 m (at the mark of 100.00 m) with the idea that below the tunnel there should be impermeable soil preventing from the underlying groundwater inrush. It is possible to construct tunnels of the accelerating complex using tunnel shields with a simultaneous wall timbering by tubing or falsework concreting.
Standard tunnel shields in the drift clay provide for daily speed of the drilling progress specified by the Project of the accelerator (it is needed for tunnel approximately 2.5 y’s).
BCD document (Conventional Facilities part)
Documentation and Cost Estimation
Site Assessment MatrixFirst official document from Russian State Project Institute with estimations on: Conventional facilities cost Siting (tunnel, land acquisition) cost and time schedule Energetics and power cost operational cost Labor cost
JINR prepared and filled the followingDocuments for the possible hosting ILC:
The overall value on consolidated estimated calculations in the prices of year 2006 for civil engineering work, underground and surface objects of the main construction gives the sum in order of 2,3 B$, including 1 B$ of costs of the tunnels construction for linear accelerator, all its technological systems and mines.
Cost of power supply objects which will provide electric power directly from generator sources with special (favorable) cost of energy (tariff) is of order of 170 M$.
Structure
JINR participation in ILC
Accelerator physics & techniques
Detectors Particle PhysicsDetector concepts
R&DExperiments &Tests
Program for new physics
& experiments
R&DTest facilitiesInfrastructure
SitingSafety
Scientific Council of JINR (20.01.2006):• encourages JINR to be involved in the ILC design effort and to invest appropriate resources in scientific and technological developments to support its ability to play a leading role in the ILC project;• supports the intention of JINR to participate actively in the ILC project and the possible interest of JINR to host the ILC
JINR Committee of Plenipotentiaries approved this recommendation on 25.03.2006The Committee of Plenipotentiary Representatives of the Governments of the Member States is the supreme body governing the Institute.
JINR at ILC
Plans on opening of new themeJINR participation in design, construction and testing of prototype elements of the ILC accelerator complex (2007-2009).
Studying problem and main goal of researches:Development and creation of accelerator complex elements, study of the beam dynamics in linear colliders.
Participating countries and international organizationsBelarus, Germany, Italy, Russia, USA, Japan, CERN
1. Creation of the ILC injection complex prototype. Development and study of electron sources on the base of photocathode and control laser system. Creation and launching of the electron injector prototype with RF or DC gun.
2. Development and creation of the test facility on base of the electron linear accelerator LINAK-800 for testing with high-energy electron beam of accelerating RF resonators, beam parameter diagnostics and transportation channels prototypes for ILC. Creation of the free electron laser on the base of photo-injector and linac LINAK-800. Development and testing of RF system elements of the linear accelerator.
3. Researches on possible creation of high-precise metrological laser complex with extended coordinate length up to 20 km.
4. Development and creation of cryogenic modules for the acceleration system of linac. Participation in creation of design documentation (work drawings) in ANSYS standard for manufacturing at ZANON (Milano) plant the first cryostat prototypes for ILC.
5. Preparation of design documentation on creation of hardware-software complex and facility for study of cryomodules, with the goal of further transition to production of documentation for mass cryostats fabrication and/or their element with refering to technologies and standard group of of the work performers.
6. Theoretical study of electron beam dynamics in transportation channels using software packages, calculation of electric and magnetic fields in accelerating structures, transportation systems and systems of e-/e+ beam formation.
7. Preparation of the project of hardware-software complex for studies of radiation stability of superconductive materials using powerful , e, n beams
8. Engineering studies and design works with purpose of the study and preparing the possible hosting of ILC in the region near Dubna.
9. Development of the magnetic systems of ILC. Calculation on choosing parameters of electromagnetic elements for Damping Rings (DR). Development and creation of the magnetic systems on base of superconducting and warm electromagnets, also for constant magnet variant.
LHE groundMachinery Hall # 2:
Possible place for location of the Test Bench for experiments on superconducting RF cavities.Adv: Large hall, Power supply,Water supply, very close to systems for liquid Helium and other cryogenics
LNP ground Building 118Location of constructed LINAC-800.Test of RF accelerator sections and cryo modulesLINAC with super-conducting RF cavity(power,water, ...
LINAC-800 – first electron beam on 27.04.2006
LNP ground
Building 108 (LEPTA project)2 experimental Halls(water, power, …)
Test Bench forPhoto Injector
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