**[New Proton Driver]{.smallcaps}**

> **19.d. [Background]{.underline}**

In the Fermilab Long Range Planning Committee report, a new Proton
Driver has been identified as a possible future construction project.
The DOE's strategic plan has listed Neutrino Superbeam/Proton Driver as
one of 28 new facilities it will build in the next 20 years. These
recent developments encourage efforts on the Proton Driver.

**19.f. [Accomplishments in FY04]{.underline}**

A revised Proton Driver Study report FERMILAB-TM-2169 has been
published. This document describes two design options, one based on an 8
GeV superconducting linac, another based on an 8 GeV rapid cycling
synchrotron. It also includes a 2-MW Main Injector upgrade design.

A new charge from the Fermilab Director asks for preparation of
documentation sufficient to establish mission need for the Proton Driver
as defined by DOE's CD-0 process. To support this mission, a Proton
Driver study group has been formed in the Accelerator Division. The
group's work includes:

-   Design of the low energy section (warm part) of a new linac

-   Design of an 8 GeV H^-^ injection line

-   Main Injector upgrades

-   Target and beam line upgrades

-   Collaboration with the Technical Division on cryogenic and RF system
    design of an 8 GeV superconducting linac

-   Further improvement of the 8 GeV synchrotron option

-   Cost and schedule estimate of the above

> **19.g.1. [Accomplishments Expected in FY05]{.underline}**

Fermilab is expected to make a proposal to DOE for CD-0 approval of a
Proton Driver project in FY05. The R&D work will be the responsibility
of the Technical Division and Accelerator Division. Work in the
Accelerator Division will include:

-   Dual harmonic magnet power supply

-   Laser chopping

-   Thin metallic beam pipe prototyping

-   Warm magnet R&D

-   Superconducting AC magnet R&D

-   High brightness H^-^ source

-   RFQ

-   Alpha magnet

-   Stripping foil

-   Collimators

-   Gamma-t jump system

-   Large aperture kickers

-   Large aperture quadrupoles

-   Dual power amplifiers for the Main Injector RF cavity

This work together with the work carried out in the Technical Division
will give a solid foundation to the Fermilab proposal.

**19.g.2. [Future Accomplishments Expected in FY06 and
Beyond]{.underline}**

If CD-0 approval is granted, work will concentrate on design allowing
for the reviews of technology, cost and schedule (project stages CD-1
and CD-2).

## TECHNICAL DIVISION'S CONTRIBUTION TO

##  GENERAL ACCELERATOR DEVELOPMENT

## [Proton Driver]{.smallcaps}

> **19.d. [Background]{.underline}**

One proposal for replacement of the present Fermilab Proton Source
(Linac and Booster) is based on a superconducting 8 GeV H-minus Linac.
This Linac design is based on a combination of the 805 MHz RF system to
be used at the Spallation Neutron Source (SNS) at Oak Ridge, and the
1207.5 MHz RF system used at the TESLA Test Facility (TTF) at DESY in
Germany. The design goal is to deliver five times more protons per
second than the present Proton Source. The 10 Hz repetition rate of this
Linac will easily provide for the Main Injector's needs, as well as many
other physics missions that require high brightness proton or electron
beams. Examples of such missions could include a Neutrino Superbeams,
Neutrino Factory, Muon Collider accelerator experiments, Spallation
Neutrino Source studies, High Energy Hadron Collider accelerator
studies, and fixed-target experiments (pion, muon, neutrino and kaon
studies). Of course this Linac could also provide a solid base for
development of a high-energy Linear Collider or FEL.

The accelerating structures of the Linac contain about 400
superconducting cavities. To allow for accelerating multiple electron
pulses between proton injection pulses, all cavities would be re-phased
between pulses or even within the same pulse to compensate for frequency
shifts due to electrodynamic forces or microphonic effects. Development
of a fast ferrite phase shifter that would permit using one klystron to
feed several cavities will dramatically reduce the associated costs of
the Linac's RF power distribution system compared to the SNS. A
realistic goal for this program is the development of a prototype RF
power distribution system in 2005.

### 19.f. [Accomplishments in FY04]{.underline}

This fiscal year will mark the beginning of a major Technical and
Accelerator Division effort to develop the design for a new intense
Proton Source. Following the charge from the director the team will
focus on developing the design for an 8-GeV SCRF linac. In addition,
cost and schedule estimates will be prepared for the linac and an 8-GeV
synchrotron so that a technology choice can be made. A parallel effort
will develop the Physics case such that by early 2005 on can request
CD-0 from the DOE. FY04 will focus on conceptual design, simulation,
site issues, and cost estimates.

R&D on a fast ferrite phase shifter will begin with the goal to make an
optimal choice among competitive candidates (coaxial or
waveguide-based). Besides its good reliability, the goal parameters of
the shifter are:

-   Peak power - 500kW,

-   Average power - 6 kW;

-   Phase adjustment - 90 degree

-   rise time - 100μs;

-   Insertion loss - \< 0.2 dB (300W of average RF power dissipation),

-   VSWR - \<1.3 over range of phase adjustment.

A conceptual design of the chosen version of the shifter will be
analyzed. Fast phase shifter prototype construction and testing will
begin.

**19.g.1. [Accomplishments Expected in FY05]{.underline}**

##### A large effort will go into the final development of two Proton driver designs, the SCRF linac and the synchrotron. Both will be developed to the point that a technology choice can occur. This will require careful cost and schedule estimates using common methodology. A Technical Design Report for the chosen technology will be prepared. Documentation sufficient for CD-1 and CD-2 will be prepared and submitted to the DOE. Advanced R&D in support of the chosen design will be pursued. A full proposal will be submitted to the DOE for construction of the Proton Driver and doubtlessly heavily reviewed. 

**19.g.2. [Future Accomplishments Expected in FY06 and
Beyond]{.underline}**

##### R&D on the proton driver will increase in support of the Proton Driver Proposal and cost estimate. The focus will move to engineering design, cost optimization, risk mitigation, and development engineering prototypes. The level of effort will be substantially increased on civil and site development.