# Presentation: 651113

## Project X RD&D Plan325 MHz Linac including             High Intensity Neutrino Source (HINS) Program

- Bob Webber
- AAC Meeting
- February 3, 2009

## Outline

- Scope of the 325 MHz Linac section
- Requirements of the 325 MHz Linac section
- Current Configuration of the 325 MHz Linac
- Primary technical issues
- Description of the role and scope of the HINS program
- Strategy to address technical issues
- Goals of the RD&D plan by year
- Possible collaborators
- Summary

## 325 MHz Linac Scope

- To be clear, there is just one Project X Linac based on an integrated and comprehensive accelerator physics design to meet Project X beam requirements
- Project X Initial Configuration Document (ICD) specifies two major Linac subsystems:
- A front end linac operating at 325 MHz
- An 8 GeV linac operating at 1300MHz
- The differentiation is for project management convenience
- The 325 MHz Linac subsystem:
- Comprises the low-energy end of the  Project X Linac
- Includes the ion source and the entire accelerator upstream of the 1.3 GHz cavity section

## 325 MHz Linac Requirements

- Serve as the low-energy front-end to the 1.3 GHz Linac section
- Deliver 1.25 msec pulses of 1.6E14 H- ions at 420 MeV at pulse rates up to 5 Hz
- Provide transverse and longitudinal beam emittance and bunch parameters required to:
- Match into the 1.3 GHz Linac
- Avoid unacceptable beam losses at high energies
- Incorporate, into the 1.25 msec beam pulse, a 53 MHz structure to facilitate pseudo bunch-to-bucket transfer into the Recycler Ring and an 89 kHz structure to facilitate a 700 microsecond abort/extraction gap in the Recycler ring

## 325 MHz Linac Configuration per ICD

- Configuration is based on Proton Driver/HINS design and technologies
- 50 keV H- ion source
- 2.5 MeV RFQ
- 2.5 MeV Medium Energy Beam Transport (MEBT) including two re-buncher RF cavities and a 325 MHz beam chopper
- Sixteen copper crossbar-H cavities in room temperature section to 10 MeV
- Eighteen β=0.22 SC single-spoke resonator (SSR1) cavities to 30 MeV
- Thirty-three β =0.4 SC single-spoke resonator (SSR2) cavities to 120 MeV
- Forty-two β =0.6 SC triple-spoke resonator (TSR) cavities to 420 MeV
- SC solenoids provide transverse focusing from the RFQ through the SSR2 section
- SC quadrupoles provide transverse focusing starting in the TSR section.
- Seven (eight)Toshiba E3740A(Fermi) 2.5 MW klystrons driven by Fermilab bouncer-type pulse modulators provide the necessary RF power
- RF distribution system with fast ferrite vector modulators for amplitude and phase control of each individual

## 325 MHz Linac        Technical Issues

- The RD&D Document identifies 325 MHz Linac issues as:
- Physics Design
- Ion Source
- Accelerating structure design
- RF power, distribution and control systems
- Magnets, magnet power supplies, and other DC/pulsed power supply systems
- Cryogenics
- Controls
- Beam Instrumentation

## 325 MHz Linac        Technical Tasks

- First task is to re-assess and validate or modify the ICD configuration
- Within the context of the comprehensive Project X design, with realistic upgrade paths considered, and based on a performance/cost/risk assessment
- Establish the physics design of the 325 MHz Linac
- Establish the transition energy between 325 and 1300 MHz Linac sections
- Identify the “technology of choice” for accelerating structures and focusing elements, e.g. HINS or more conventional technologies
- Identify “technology of choice” for RF power generation, distribution, and control
- Technical development tasks assuming the ICD configuration
- Issues being addressed by HINS Program
- Room Temperature Linac section design
- SSR1 cavity and cryostat development
- High Power RF vector modulator development
- Solenoidal focusing system development
- Development of SSR2 and Triple-spoke SC cavities and spoke cavity cryomodules
- Incorporation of beam instrumentation into the physics and mechanical design
- Generation of CD-1 and CD-2 level engineering design and documentation for all 325 MHz Linac systems

## Goals of HINS Program

- Stated Mission - To address accelerator physics and technology questions for a new concept, low-energy, high intensity, long-pulse H- superconducting Linac; in particular, to demonstrate:
- beam acceleration using superconducting spoke-type cavity structures starting at a beam energy of 10 MeV
- multiple high power RF vector modulators controlling RF cavities driven by a single high power klystron for acceleration of a non-relativistic beam
- beam halo and emittance growth control by the use of solenoid focusing optics
- a fast, 325 MHz bunch-by-bunch, beam chopper
- The recent scope of HINS included two CM of β = 0.2 SSR1 and one CM of β = 0.4 SSR2 spoke cavities to achieve 60 MeV
- The SSR2 CM effort was recently dropped from the program

## HINS vis a vis Project X

- Management and funding of HINS currently remains independent of, but not oblivious to, Project X
- HINS managers participate intimately in Project X developments
- HINS efforts are expected to continue in support of Project X technology choices and upgrade options
- Integration of HINS management and funding with Project X will be considered subsequent to Project X CD-0
- Whether/when the integration actually occurs will be strongly coupled to whether or not HINS is expected to serve as the Project X front end
- If yes, the answer is obviously quick and complete integration
- If no, the intent would be to keep HINS as a separate program aimed at a Project X upgrade developments
- HINS is the path to achieve technology demonstrations that are important to Project X in the 2009-2012 time frame
- HINS future scope
- Currently includes two SSR1 CM taking beam to 30 MeV
- the original HINS goals could be substantially achieved with 20 MeV beam provided by just one SSR1 CM

## RFQ Installed in             HINS Facility

## Recent SC Spoke Cavity VTS Q vs E Results

- Blue - Q vs. E first (lower) and second (upper) power sweep
- Red – measured radiation

- Orange- Q vs. E at 2 K
- Blue (small) – Q vs. E at 4 K
- Green – Q vs. E at 4 K after second, slow cool down holding at  ~100 K for ~ 7 hrs to ‘invite’ Q disease
- Blue (large) –radiation at 4 K
- Red –radiation at 2 K

**RF power limited**

## Technical Strategy

- Global Linac Physics and Engineering Design
- Establish a performance/cost/risk assessment basis for judging alternative designs
- Identify credible technical alternatives within the requirements of the comprehensive Linac physics design
- Flesh out the performance and engineering aspects of alternative technologies to the point of being able to assign performance, cost, and risk weights
- Make decisions
- Continue HINS R&D Program
- Integrate with Project X as suitable
- Develop, test and demonstrate with beam
- SSR1 cavities and cryomodule
- High power RF vector modulator
- Solenoidal focusing elements
- Establish collaborative commitments as soon as possible
- Following decision on comprehensive design and technology decision
- Begin SSR2 and TSR cavity and cryomodule or alternative accelerating structure developments with the efforts of collaborators

## 325 MHz Linac RD&DGoals and Timeline

- FY09
- Continue work on comprehensive accelerator physics design
- Investigate and document alternative technologies
- Produce all documentation, based on current ICD document, required for positive CD-0 decision
- Continue HINS program emphasizing goals important to Project X, especially first pulsed power test of SSR1
- FY10
- Establish collaboration commitments
- Continue HINS program
- Complete the basic 325 MHz Linac design and technology decisions
- Begin
- Ion source development,
- SSR2 and TSR cavity electromagnetic and mechanical design (or alternate technology) and procure material for prototypes
- Low level RF development
- Systems integration efforts for other 325 MHz Linac systems
- Produce CDR documentation required for  positive CD-1 decision in early FY11

## 325 MHz Linac RD&DGoals and Timeline

- FY11
- Continue
- Ion Source prototyping and testing
- SSR2 and TSR (or alternate) prototype fabrication
- Vector modulator and RF distribution system development
- Beam instrumentation prototype design and fabrication
- Begin documentation and cost baselines required for CD-2 in FY12
- FY12
- Complete fabrication and processing of prototype accelerating structures; begin testing with RF power
- Complete
- Ion source development
- RF power distribution system design development
- Beam instrumentation prototyping
- Complete all documentation required for positive CD-2 decision in FY12

## 325 MHz Collaborators

- Some expressions of interest from the November 2008 Project X Collaborators Meeting
- ANL
- Physics design and tracking simulations
- Spoke cavity and cryomodule development, esp. triple spokes
- CERN
- Chopper development
- High power RF vector modulator development
- Indian institutions
- All aspects of superconducting cavity, power coupler and cryomodule design, fabrication, and testing
- JLAB
- SC cavity processing and dressing
- Cryogenics systems design
- LBNL
- Low level RF
- Low energy (RFQ/MEBT) section design and components
- Beam Instrumentation
- SNS
- Ion Source

## Summary

- The Project X ICD describes the 325 MHz low-energy section of the Project X Linac extending to 420 MeV and based on HINS technologies
- First priority post-CD-0 effort is to confirm or modify this configuration based on alternative design, performance, cost, and risk studies
- The HINS program actively pursues and is accomplishing technological developments important to Project X  and its upgrade paths
-  Integration of HINS management and funding with Project X will be considered after Project X CD-0 in a manner and at a time likely influenced by Project X alternative technology assessments
- The January 2008 RD&D document identifies the issues important to the  325 MHz Linac and lays out a timeline for addressing those
- With the addition of SSR2 design, the issues remain otherwise unchanged
- Schedule needs to be shifted by one year
- Potential collaborators for major 325 MHz Linac systems and components have made their interests known