# Presentation: 408857

## On the Way to ILC

- Shekhar Mishra
- Fermilab
- Talk presented on behalf of ILC-GDE
- 2/16/06

- Talk Presented at the 2006 Aspen Winter Conference: "Particle Physics at the Verge of Discovery"

## International Linear Collider: Performance Specification (White Paper)

- Initial maximum energy of **500 GeV**, operable over the range 200-500 GeV for physics running.
- Equivalent (scaled by 500 GeV/s) integrated luminosity for the first four years after commissioning of **500 fb****-1**.
- Ability to perform energy scans with minimal changeover times.
- Beam energy stability and precision of 0.1%.
- Capability of **80%** electron beam **polarization** over the range 200-500 GeV.
**Two interaction regions**, at least one of which allows for a crossing angle *enabling **** collisions*.
- Ability to operate at **90 GeV** for calibration running.
- Machine upgradeable to approximately **1 TeV**.

## Road to: Reference Design Report 

- 1st ILC Workshop at KEK (11/2004)
- working groups (WG) formed to begin identifying contentious design issues
- 2nd ILC Workshop Snowmass (8/2005)
- modified WG continue identifying _baseline_ design and _alternatives_
- newly formed ‘Global Groups’ begin to discuss and catalogue global design issues
- 2nd Snowmass week: concentrate on the list of ‘Top 40’ critical design questions
- 1st Meeting of the ILC-GDE (12/2005)
- Acceptance of the Baseline Configuration Document (BCD)
- Start work towards the Reference Design Report (12/2006, with Cost)
- Formation of Accelerator System, Technology and Global systems
- Formation of
- Design and Cost Board, Change Control Board and R&D Board

- ITRP Recommendation (Aug 2004) : Superconducting RF is accelerating technology for ILC

## GDE

- ICFA

- FALC

- FALC
- Resource Board

- ILCSC

- Directorate

- Executive Committee

- Global
- R&D Program

- RDR
- Design Matrix

- R & D Board

- Change Control Board

- Design Cost Board

- GDE RDR / R&D Organization

**GDE**

## GDE RDR / R&D Organization

- ICFA

- FALC

- FALC
- Resource Board

- ILCSC

- GDE
- Directorate

- GDE
- Executive Committee

- Global
- R&D Program

- RDR
- Design Matrix

- GDE
- R & D Board

- GDE
- Change Control Board

- GDE
- Design Cost Board

**ILC**
**Design**
**Effort**

**ILC**
**R&D**
**Program**

## Mission of Global Design Effort

- Produce a design for the ILC that includes
- A detailed design concept
- Performance assessments
- Reliable international costing
- An industrialization plan
- Siting analysis
- Detector concepts and scope
- Coordinate worldwide prioritized proposal driven R & D efforts
- To demonstrate and improve the performance
- Reduce the costs
- Attain the required reliability, etc.

## Slide 7

## The Baseline Machine (500GeV)

- not to scale

- ~30 km

- e+ undulator @ 150 GeV (~1.2km)

- x2

- R = 955m
- E = 5 GeV

- RTML ~1.6km

- ML ~10km (G = 31.5MV/m)

- 20mr

- 2mr

- BDS 5km

## Luminosity Table

-  						min	nom	max
- Bunch charge       	N	1 	2	2	x10^10
- Number of bunches	nb	1330	2820	**5640**
- Linac bunch interval	tb	**154**	308	461	ns
- Bunch length       	z	**150**	300 	500	m
- Vertical emittance        y	**0.03**	0.04	0.08 mm.mrad
- IP beta (500GeV)   	x	**10**	21	21	mm
-                    		y	**0.2**	0.4	0.4	mm
- IP beta (1TeV)     	x	**10**	30	30	mm
-                   			y	**0.2**	0.3	0.6	mm

## Baseline Electron Source 

-  DC Guns incorporating photocathode illuminated by a Ti: Sapphire drive laser.
-  Long electron microbunches (~2 ns) are bunched in a bunching section
-  Accelerated in a room temperature linac to about 100 MeV and SRF linac to 5 GeV.

## Baseline Positron Source

- Helical Undulator Based Positron Source with Keep Alive System
- The undulator source will be placed at the 150 GeV point in main electron linac.
- This will allow constant charge operation across the foreseen centre-of-mass energy operating range.

## ILC Damping Ring: Baseline Design

** ****Positrons:** Two rings of ~ 6 km circumference in a single tunnel.
-  Two rings are needed to reduce e-cloud effects unless significant progress can be made with mitigation techniques.
-  Preferred to 17 km due to:
- Space-charge effects
- Acceptance
- Tunnel layout (commissioning time, stray fields)
** ****Electrons:** one 6 km ring.
-  Preferred to 3 km due to:
- Larger gaps between mini-trains for clearing ions.
- Injection and extraction kickers ‘low risk’

## Main Linac: Baseline RF Unit

## SRF Cavity Gradient

|  | Cavity type | Qualifiedgradient | Operational gradient | Length* | energy |
| --- | --- | --- | --- | --- | --- |
|  |  | MV/m | MV/m | Km | GeV |
| initial | TESLA | 35 | 31.5 | 10.6 | 250 |
| upgrade | LL | 40 | 36.0 | +9.3 | 500 |

- * assuming 75% fill factor

- Total length of one 500 GeV linac  20km

## Baseline ILC Cryomodule

-  The baseline ILC Cryomodule will have 8 9-Cell cavities per cryomodule. The quadrupole will be at the center in the baseline design.
-  Every 4th cryomodule in the linac would include a quadrupole with a corrector and BPM package.

## Modulator

- Baseline

- Alternate

- The Bouncer Compensated Pulse Transformer Style Modulator

- Operation: an array of capacitors is charged in parallel, discharged in series. (~2m)Will test full prototype in 2006

## RF Power: Baseline Klystrons

- Thales

- CPI

- Toshiba

- Specification:
- 10MW MBK
- 1.5ms pulse
- 65% efficiency

- ILC (XFEL @ DESY) has a very limited experience with these Klystrons. Production and operation of these Klystron are issues that needs to be addressed.

## Beam Delivery System: Baseline & Alternatives

- Baseline (supported, at the moment, by GDE exec)
- two BDSs, 20/2mrad, 2 detectors, 2 longitudinally separated IR halls
- Alternative 1
- two BDSs, 20/2mrad, 2 detectors in single IR hall @ Z=0
- Alternative 2
- single IR/BDS, collider hall long enough for two push-pull detectors

## From Baseline to a RDR 

**Jan**

**July**

**Dec**

**2006**

**Freeze Configuration**
**Organize for RDR**

**Bangalore**

**Review **
**Design/Cost **
**Methodology**

**Review Initial**
**Design / Cost**

**Review Final**
**Design / Cost**
**RDR Document**

**Design and Costing**

**Release**
**RDR**

**Frascati**

**Vancouver**

**Valencia**

**Notes:**
Redo!!!

## ILC R&D 

- Major laboratories around the world are working on the ILC Accelerator R&D.
- Europe
- DESY (TESLA) (55 Institutions)
- European XFEL
- CARE (11 Institutions)
- EuroTeV (27 Institutions)
- UK-LCABD (15 Institutions)
- Americas (9 Laboratories and Universities)
- Fermilab
- SLAC
- Asia (6 Institution in 5 countries)
- KEK

- Some Highlights of R&D Activities

## Key Issues: ILC Main Linac Accelerator Technology

- The feasibility demonstration for the ILC requires that a cryomodule be assembled and tested at the design gradient of 35 MV/m.
- Cavity technology development to routinely achieve _>_ 35 MV/m and Q ~0.5-1e10,
- Finalize the design of an RF Unit and evaluate the reliability issues. It is important to fully test the basic building block of the Linac.
- High Power Coupler, HOM, Tuner etc.
- 10 MWatt Multi-Beam Klystron, Fabrication, Operation and reliability
- RF Distribution, Controls and LLRF
- Instrumentation and Feedback
- Quadrupole, Corrector and Instrumentation package
- Cryogenic Distribution

## Europe: ILC R&D

- DESY is leading the ILC R&D in Europe. The XFEL at DESY uses ILC Technology and have common R&D goals.
- Cavity Gradient
- Industrial studies and development of Main Linac Components.
- Coupler
- RF Power
- Cryogenics (LHC)
- Instrumentation
- Beam Delivery System

## DESY: ILC Accelerator Modules in Operation

**At present DESY is operating modules **
**2*****	****ACC1****	****Febr 04**
**1*****	****ACC2 ****	****June 02**
**3*****	****ACC3****	****April 03 **
**4 ****	****ACC4****	****April 03**
**5****	****ACC5****	****April 03**

**In ****single cavity measurements   **** **
** ****6 out of 8 cavities reach 30 MV/m!****  **

**ACC5**

## ILC R&D at Fermilab

- ILC R&D effort at Fermilab is focused on key design & technical issues in support of the RDR, cost estimate and eventually the CDR for the ILC.
- We also have the goal of positioning the Americas to host the ILC at Fermilab
- Our efforts are focused on two main areas of the ILC
- Main Linac Design
- Civil and Site Development
- Main Linac R&D:
- The goals are to demonstrate the feasibility of all Main Linac technical components, develop engineering designs, estimate costs, explore cost reduction, and engage US industry
- Civil and Site Development
- Fermilab is working with the GDE and international partners to develop a matrix for comparing possible ILC sites
- We also work to develop U.S. sites on or near Fermilab

## ILC 1.3 GHz Cavities @ FNAL

- Industrial fabrication of cavities.
- BCP and vertical testing at Cornell (25 MV/m)
- EP and vertical testing at TJNL. ( 35 MV/m)
- Joint BCP/EP facility being developed ANL  (late 06)
- High Power Horizontal test facility @ FNAL (ILCTA-MDB)
- Vertical test facility under development @ FNAL ( IB1)
- Single/large Crystal cavity development with TJNL

**4 cavities received from ACCEL**
**4 cavities on order at AES**
**4 cavities expected from KEK**

**Bead pull RF **
**Testing @ FNAL**

**Joint ANL/FNAL**
**BCP/EP **
**Facility**

## Jlab: Large Grain/Single Crystal Niobium

- Nb Discs

- LL cavity 2.3GHz

- Epeak/Eacc = 2.072
- Hpeak/Eacc = 3.56 mT/MV/m

## SLAC: Accelerator Design (RDR)

- Strong efforts throughout the design effort
- Electron and positron sources
- Contributions to the damping rings and RMTL
- Main linac design and instrumentation
- Rf sources
- Beam Delivery System
- Civil construction and conventional facilities
- Able to provide leadership for some RDR Area Sub-systems

## SLAC: ILC R&D Program

- Broad R&D Program (cont.)
- Linac rf sources
- Marx generator modulator
- Electron and Positron sources
- NC structure, E-166, electron laser, and cathode
- Damping rings
- SEY studies in PEP-II

**SEY Test Chamber for PEP-II**

**Positron capture****structures**

**12 KV Marx Cell**

## KEK: ILC Activities Highlights

## KEK ATF Facility for DR and FF

## KEK: Main Linac RF Unit R&D

- Goal: Achieve Higher Gradient >40 MV/m in a new Cavity Design

## Summary

-  After the technology selection the ILC Collaboration has made considerable progress towards the design of the ILC.
-  The Baseline and Alternate design for each major Accelerator subsystems were defined at Snowmass 2005.
-  The ILC-GDE has a approved the Baseline Configuration Document.
-  The ILC-GDE is developing the ILC Reference Design Report, with cost estimate. It is expected to be done by the end of CY06
-   The ILC R&D around the world is moving fast with focus on key Accelerator Issues.