# Presentation: 804760

## US LHC Accelerator Research Program

- Jim Strait, Fermilab
- For BNL-FNAL-LBNL Collaboration
- 1st LAPAC Meeting
- 17-18 June 2002

***brookhaven - fermilab - berkeley***

_**US LHC Accelerator Research Program**__**                              **_

## Slide 2

## Slide 3

## The US Hadron Accelerator Community and CERN plan to continue the collaboration established for the construction of LHC.  
The goals of this program are to 
Extend and improve the performance of the LHC, so as to maximize its scientific output.
Maintain and develop the US labs’ capabilities, so that the US can be the leader in the next generation of hadron colliders. 
Serve as a vehicle for US accelerator specialists to pursue their research.
Train future generations of accelerator physicists.
Continue to advance international cooperation on large accelerators. 
Fermilab has been appointed the “Host Laboratory” to lead this program. 
CERN management strongly supports our continued collaboration.

- The goals of this program are to
- Extend and improve the performance of the LHC, so as to maximize its scientific output.
- Maintain and develop *the US labs’ capabilities*, so that the *US can be the leader* in the next generation of hadron colliders.
- Serve as a vehicle for US accelerator specialists *to pursue their research.*
*Train future generations* of accelerator physicists.
- Continue to advance *international cooperation* on large accelerators.
- Fermilab has been appointed the “Host Laboratory” to lead this program.
- CERN management strongly supports our continued collaboration.

**US LHC Accelerator Research Program**

## US LHC Accelerator Research Program

- US collaboration on the LHC accelerator is an essential component of
- the US HEP program.
- It supports the LHC experiments by helping to maximize the LHC’s scientific output.
- It builds on the domestic hadron accelerator programs.
- It involves us with the state-of-the-art in hadron machines, balancing the growing domestic emphasis on linear e+e– colliders.
- It is a cost-effective means to:
- Protect our intellectual and physical investment in advanced hadron colliders and the technologies that make them possible.
- Continue to advance our capabilities, with an eye to the next generation very large hadron collider.

## Our program is organized in four areas of research:
Accelerator physics experiments and calculations.
Understanding performance limitations of current IRs and developing new designs.
Participation in the sector test and machine start-up.
Beam dynamics calculations and experiments.
Developing high performance magnets for new higher luminosity IRs.
Large-aperture, high gradient quadrupoles using Nb3Sn.
High-field beam separation dipoles and strong correctors.
Developing advanced beam diagnostics and instrumentation.
Commissioning our hardware for the LHC.

- Accelerator physics experiments and calculations.
- Understanding performance limitations of current IRs and developing new designs.
- Participation in the sector test and machine start-up.
- Beam dynamics calculations and experiments.
- Developing high performance magnets for new higher luminosity IRs.
- Large-aperture, high gradient quadrupoles using Nb3Sn.
- High-field beam separation dipoles and strong correctors.
- Developing advanced beam diagnostics and instrumentation.
- Commissioning our hardware for the LHC.

- US LHC Accelerator Research Program**Planned Activities**

## Interaction Region Development

- The IRs will be among the limiting systems. Replacement of the existing quads is a necessary route to higher luminosity.
- The existing quadrupoles have a radiation lifetime of 6-7 years at design luminosity, and we must be prepared to replace them by about 2014.
- US-CERN-KEK collaboration meeting on IR upgrade options was held 11-12 March 2002.
- Presentations available at *http://cern.ch/lhc-proj-IR-upgrade*
- Second meeting is planned for November 2002.
- Several designs for new IRs have been proposed.
- Maintain the existing optical layout, but with larger aperture quadrupoles made of Nb3Sn superconductor.
- Re-arrange the IR to place a beam separation dipole before the quads, which then become smaller aperture, twin-bore magnets.

## LHC Upgrade Study at CERN

- Presentation by L. Tavian, CERN

## US-CERN-KEK Meeting on IR Upgrades

- Session Summary by JBS, Fermilab

- Presentation by T. Sen, Fermilab

- “10” beam envelope for * = 25 cm

- Presentation by O. Brüning, CERN

## US-CERN-KEK Meeting on IR Upgrades

- Session Summary by JBS, Fermilab

## US Program on IR Upgrade Magnets

- Goal: Development of technologies and prototypes of superconducting magnets for high-luminosity inner triplets, as part of an upgrade program to raise LHC luminosity 1034  1035 cm-2s-1.
- Program focus is on Nb3Sn, large-aperture quadrupoles.
- Builds on “generic” Nb3Sn dipole R&D programs.
- Initial program is to develop technologies, not specific designs.
- Specific design choices will be made after several years of magnet R&D and related accelerator design studies.
- Not currently part of our program, but necessary for upgraded IR:
- High-field beam-separation dipoles, required in all IR upgrades scenarios under consideration.
- Large-aperture linear and non-linear correction magnets will have substantially higher pole-tip fields than in the baseline IRs and may become quite challenging.
*Nature of collaboration with CERN and KEK still being established.*

## US Program on IR Upgrade Magnets

- Program concentrates on quadrupoles for 2nd generation IR, *but*2nd generation IR design is not known now.
- AP studies will evaluate various proposed IR optics and layouts.
- Magnet R&D will develop and evaluate magnet designs and technologies.
- Preliminary choices for development of specific magnet design(s) will be made ~2005.
- Final choice of IR design and magnet design will most likely be made after initial LHC operation => ~2008.
- Main approach is development of large aperture cos 2 quad of “conventional” design, made with Nb3Sn Rutherford cable (W&R).
- Alternates to be studied include:
- Block-type and race-track coils.
- React-and-wind coils made with small wires and cables.
- Cable and conductor R&D
- “Generic” R&D continues under DOE Nb3Sn program with industry.
- Specific topics relevant to LHC designs are part of this program.

## US Program on IR Upgrade Magnets

- FY 2002-2004 – Conceptual Design Studies
- 	-	Establish magnet target parameters (with US and CERN AP groups).	  Aperture, field strength, single vs. twin aperture, coil geometry, ...
- 	-	Develop and compare different design and technological approaches	for quads, dipoles and correctors.
- 	-	Selection of conceptual magnet designs and basic technologies.
- FY 2003-2009 – Short model R&D
- 	-	70 mm Nb3Sn using existing tooling for baseline IR quadrupoles.-	Development and coil tests of wide, fully keystoned Nb3Sn cable.
- 	-	Investigation of react-and-wind and wind-and-react technologies.
- 	-	Relies on continued Nb3Sn development program with industry.
- 	-	Models of quad design selected by conceptual design studies.
- 	-	Development of large aperture, high-field dipoles or correctors ...	depending on collaborative interest by CERN and KEK.

## US Program on IR Upgrade Magnets

- FY 2009-2011 – Full-scale prototypes.
- 	-	Final design decisions follow initial LHC operational experience.
- 	-	Large-aperture single or twin-aperture quads – full length in prototype	cryostat.-	Large-aperture dipoles or correctors (depending on collaborative 	interest by CERN and KEK).
- FY 2011 – Final design report.
- 	-	Deliverable: complete design package, ready to manufacture.
- 	-	Decide who (US, CERN, KEK, industry) builds which IR upgrade	magnets.
- Cost estimate for this program is being developed, based on extensive experience of 3 US labs with LHC IR magnets, Nb3Sn R&D programs, etc.

## Accelerator Physics

- A broad range of accelerator physics activities are planned.
- Interaction Region studies.
- Performance studies for baseline IR.
- 2nd generation IR designs.
- AP calculations and experiments.
- Beam-beam interaction studies.
- Electron cloud studies.
- Non-linear dynamics.
- Synchrotron radiation in cryo environment.
- Studies of feasibility/applicability of new instrumentation methods.
- Phase locked loops.
- Wire compensator for long-range beam-beam interaction.
- Electron lens.
- Bunch-by-bunch closed orbit correction.

## Accelerator Physics

- Machine development.
- Injection test from IR8 to IR6  -  2006.
- Machine start-up and commissioning  -  2007-2008.
- Ongoing beam studies and machine development  -  2008...
- LHC-relevant machine studies with RHIC and Tevatron, in collaboration with CERN.
- Remote data acquisition and (eventually) control room.
- Cost is mainly salaries and travel.

## Instrumentation and Diagnostics

- Development and possible implementation of “2nd generation” beam
- diagnostics:
- Luminosity instrumentation to be installed in IR absorbers.
- Allows fast, bunch-by-bunch measurement of luminosity, crossing angle, and collision point.
- Provides feedback signal for keeping beams in collision.
- R&D on fast, high-pressure ionization chamber started under construction project.
- Alternate technology also under consideration by CERN - decision next year.
- Longitudinal profile monitor.
- Conceptual design studies have begun, in collaboration with CERN instrumentation group.
- Phase-locked loops for tune and chromaticity control.
- Based on systems currently being developed for RHIC.

## Instrumentation and Diagnostics

- Longer-term ideas, whose feasibility or necessity must be demonstrated.
- Electron lens for bunch-by-bunch tune control, currently being developed for the Tevatron.
- Bunch-by-bunch closed orbit control and feedback system. Necessity for this must be experimentally investigated with LHC beam.
- Other advanced feedback systems, to be developed as ideas emerge or limitations of LHC become known.
- Cost estimates for earlier items can be confidently made based on
- specific designs and actual hardware experience.
- Activity on longer-term ideas will not become significant until LHC begins
- to operate.

## Hardware Commissioning

- US responsibility for systems delivered under the present construction project ends when CERN accepts them (2002-2004).
- We plan, as part of the research program, to participate in the commissioning of our equipment in the LHC tunnel.
- Serve as ‘consultants’ to CERN during installation of our equipment (2004-2006).
- Full participation in 1st operation of our systems - quads, dipoles, feedboxes, absorbers (2005-2007).
- Cooldown and powering of magnets.
- Operation of cryogenic control systems.
- Quench protection.
- Vacuum and alignment.
- First beam operation.
- Cost is entirely salaries (physicists and engineers) and travel.

## Cost Estimates and Funding

- We are developing cost estimates for all program elements, with a ~5 year time horizon, which we will update yearly.
- The Program is defined by the science and technology to meet the Program goals, and will becarried out based on optimal use of resources at the three labs.
- We lack specific guidance on funding, but have made a reasonable estimate, for planning purposes, based on informal discussions with DOE.

*Preliminary*

## Draft Organization Chart

## US collaboration on the LHC accelerator is an essential component of the US HEP program.
Supports CMS and ATLAS by improving LHC performance.
Advances our capabilities in accelerator physics and technology.
The participants at all 3 labs have agreed on the scientific program
Accelerator Physics
High performance magnets
Advanced beam instrumentation and diagnostics
Commissioning of our hardware
	and agreed on the management approach.
Advice from LAPAC will help refine the scientific and technical program.
Lehman Review is planned for later this summer.

- Supports CMS and ATLAS by improving LHC performance.
- Advances our capabilities in accelerator physics and technology.
- The participants at all 3 labs have agreed on the scientific program
- Accelerator Physics
- High performance magnets
- Advanced beam instrumentation and diagnostics
- Commissioning of our hardware
- 	and agreed on the management approach.
- Advice from LAPAC will help refine the scientific and technical program.
- Lehman Review is planned for later this summer.

**Conclusions**

## Charge to LAPAC

- The initial charge to the Committee will be to
- consider the scientific and technical quality of the proposed program
- 	and
- offer advice as to the relevance, relative priorities and appropriate schedules for the proposed activities.
- The program will be evaluated with respect to the degree to which they support the objectives of
- maximizing the scientific output of the LHC
- 	and
- contributing to the advancement of the domestic US high energy physics and accelerator programs.

## Magnet Program:
Is the range of options for technologies and designs too large; that is, should we focus more strongly on a more limited set of problems?  
If so, which paths look most promising to lead to practical quadrupoles for LHC by about 2014?
Is the time scale for converging on the specific design of an IR quad appropriate?

Accelerator Physics:
Which topics have the potential to make the strongest impact on LHC performance.
Given that many subjects are closely related to problems currently being addressed for the Tevatron and RHIC, which topics are most important to be supported under the LHC research program?

- Is the range of options for technologies and designs too large; that is, should we focus more strongly on a more limited set of problems?
- If so, which paths look most promising to lead to practical quadrupoles for LHC by about 2014?
- Is the time scale for converging on the specific design of an IR quad appropriate?
- Accelerator Physics:
- Which topics have the potential to make the strongest impact on LHC performance.
- Given that many subjects are closely related to problems currently being addressed for the Tevatron and RHIC, which topics are most important to be supported under the _LHC_ research program?

- Charge to LAPAC

## Instrumentation:
Evaluate the program presented with respect to the objectives stated as part of the “generic” charge.
Hardware Commissioning:
Is the proposed level of involvement with hardware commissioning about right?
Should we consider involvement in hardware commissioning of LHC systems that we did not build?
To help bring the LHC up as quickly as possible.
To learn as much as possible from LHC experience.
	If so, what areas are most likely to be important to explore?

Any other observations or comments on any aspect of the program 
presented would be welcome.

- Evaluate the program presented with respect to the objectives stated as part of the “generic” charge.
- Hardware Commissioning:
- Is the proposed level of involvement with hardware commissioning about right?
- Should we consider involvement in hardware commissioning of LHC systems that we did not build?
- To help bring the LHC up as quickly as possible.
- To learn as much as possible from LHC experience.
- 	If so, what areas are most likely to be important to explore?
- Any other observations or comments on any aspect of the program
- presented would be welcome.

- Charge to LAPAC