JRA3 in the CARE proposal

***Version 26/09/2003***

**[Title]{.underline}: High Intensity Pulsed Proton Injectors**

**[Acronym]{.underline}: HIPPI [Coordinator]{.underline}: R. Garoby
(CERN)**

![](media/image1.png){width="3.1590277777777778in"
height="1.6354166666666667in"}

**[Participating Laboratories and Institutes]{.underline}:**

+----------------------------+-------+-----+-------+-------+--------+
| Institute                  | Ac    | C   | C     | Scien | Asso   |
|                            | ronym | oun | oordi | tific | ciated |
| (participant number)       |       | try | nator | Co    | to     |
|                            |       |     |       | ntact |        |
+----------------------------+-------+-----+-------+-------+--------+
| CCLRC Rutherford Appleton  | CCLRC | UK  | P.    | C.    |        |
| Laboratory (20)            |       |     | N     | Prior |        |
|                            |       |     | orton |       |        |
+----------------------------+-------+-----+-------+-------+--------+
| Commissariat à l'Energie   | CEA   | F   | R.    | A.    |        |
| Atomique (1)               |       |     | Al    | Mo    |        |
|                            |       |     | eksan | snier |        |
+----------------------------+-------+-----+-------+-------+--------+
| CERN (17)                  | CERN  | CH  | H.    | R.    |        |
|                            |       |     | Has   | G     |        |
|                            |       |     | eroth | aroby |        |
+----------------------------+-------+-----+-------+-------+--------+
| Forschungszentrum Jülich   | FZJ   | D   | R.    | R.    |        |
| (7)                        |       |     | Tölle | Tölle |        |
+----------------------------+-------+-----+-------+-------+--------+
| Gesellschaft für           | GSI   | D   | N.    | L.    |        |
| Schwerionenforschung,      |       |     | A     | Gro   |        |
| Darmstadt (4)              |       |     | ngert | ening |        |
+----------------------------+-------+-----+-------+-------+--------+
| Institut für Angewandte    | I     | D   | U.    | U.    |        |
| Physik - Frankfurt         | AP-FU |     | Ratz  | Ratz  |        |
| University (5)             |       |     | inger | inger |        |
+----------------------------+-------+-----+-------+-------+--------+
| INFN-Milano (10)           | IN    | I   | S.    | C.    | INFN   |
|                            | FN-Mi |     | Gui   | P     |        |
|                            |       |     | ducci | agani |        |
+----------------------------+-------+-----+-------+-------+--------+
| CNRS Institut de Physique  | C     | F   | T.    | T.    | CNRS   |
| Nucléaire d'Orsay (3)      | NRS-I |     | G     | Jun   |        |
|                            | N2P3- |     | arvey | quera |        |
|                            | Orsay |     |       |       |        |
+----------------------------+-------+-----+-------+-------+--------+
| CNRS Laboratoire de        | CNRS  | F   | T.    | J.M.  | CNRS   |
| Physique Subatomique et de | -LPSC |     | G     | De    |        |
| Cosmologie (3)             |       |     | arvey | Conto |        |
+----------------------------+-------+-----+-------+-------+--------+

**[Main Objectives]{.underline}: Research and Development of the
technology for high intensity pulsed proton linear accelerators up to an
energy of 200 MeV.**

**[Cost]{.underline}:**

+-----------------------------------+----------------------------------+
| **Total Expected Budget**         | **Requested EU Funding**         |
+-----------------------------------+----------------------------------+
| 12 M€ (FC) + 2.7 M€ (AC)          | **3.6 M€**                       |
|                                   |                                  |
| **Total 14.7 M€**                 |                                  |
+-----------------------------------+----------------------------------+

1*.* [Scientific and Technological excellence]{.smallcaps}

Requests from the various physics communities for secondary particle
beams have recently drastically increased. Therefore, a number of
European laboratories have pursued separate development programmes
concerning the high intensity proton linac that can deliver the primary
beam onto the target. In particular:

-   CEA and CNRS-IN2P3-Orsay on the low-energy section (3 MeV) (IPHI
    project),

-   Frankfurt University (Germany) on high-efficiency accelerating
    structures,

-   CERN on chopping and medium-energy accelerating structures,

-   CCLRC-RAL on the chopper design, ion source and RFQ development,

-   INFN-Mi (Italy), CEA (France), FZJ (Germany), CNRS-IN2P3-Orsay and
    CNRS-LPSC (France) on superconducting accelerating structures.

All these laboratories, together with GSI (Germany), have developed beam
dynamics tools aimed at mastering high-intensity beams in linacs.

1.  Objectives and originality of the joint research activity

    1.  Objectives

The HIPPI JRA is meant to foster the development of a common European
technology base for the construction of high intensity pulsed linear
accelerators. It will achieve this by coordinating the above-mentioned
efforts, realising a systematic study of several technological
alternatives up to an energy of 200 MeV. The proposed R&D activities are
intended to surpass the level of competence achieved outside Europe and
provide the technological background for substantial improvements of
facilities at three European Laboratories:

-   CERN :

    -   Improve the proton flux for fixed target experiments

    -   Upgrade the neutrino beams for CNGS experiment

    -   Increase the proton flux for the ISOLDE facility

    -   Improve the stability, reliability and integrated luminosity of
        the LHC

-   CCLRC-RAL :

    -   Increase the neutron flux of ISIS and the potential for neutrino
        beams

-   GSI :

    -   Increase the proton flux of the heavy ion synchrotron (SIS)

Although the detailed specifications will only be defined at the first
general meeting, in the autumn of 2004, the basic goals are as follows:

-   for normal-conducting accelerating structures: shunt impedance ZT^2^
    (power efficiency) higher than 40 M/m in the energy range 3-100 MeV,
    at a competitive cost with respect to conventional DTL.

-   for superconducting accelerating structures: gradient exceeding 7
    MV/m with Q 10^10^ in the energy range 100-200 MeV, at a
    construction cost comparable to normal-conducting structures.
    Development of efficient superconducting structures down to beam
    energies around 5 MeV

-   for beam chopping: switching time smaller than the distance between
    bunches at 352 MHz (about 2 ns). Moreover, the overall design of the
    chopper-line has to minimize emittance growth.

-   for beam dynamics: experimental validation of simulation codes, and
    rules for a design keeping the uncontrolled beam loss below 1W/m
    (threshold for hands-on maintenance) all along a high energy linac
    (\> 1 GeV) and the associated transfer lines.

    1.  State of the art and technical innovation

The last proton linac built in Europe was commissioned in 1988, and was
based on the technology of the 70's. The basic technology has evolved
considerably since, and the present demands for high intensity operation
require a vigorous R&D effort. For the last 10 years, most progress has
taken place in the USA and in Japan. A high intensity pulsed proton
linac is in an advanced construction phase for the Spallation Neutron
Source project at the Oak Ridge National Laboratory (USA), and another
one is being built in Japan (J-PARC at JAERI). The goal of the HIPPI JRA
is to surpass the level of competence achieved on the other continents
and provide the necessary knowledge to build world-class accelerators in
Europe.

A key feature of the HIPPI JRA is the integration of the R&D for
alternative technological solutions. Coordinated reporting of the
progress and results will permit well controlled comparative
assessments.

2.  Implementation plan of the joint research activity

Description of the Work Packages

Five Work Packages are outlined. Management and communication matters
are covered in the first. Each of the other four Work Packages is
focused on a specific technology/competence. **For their definition, the
participating laboratories have adapted their own work plans and
baseline choices to benefit from the collective efforts and avoid
duplication**. Different solutions will be investigated in parallel, and
their progress and achievements will be regularly communicated and
discussed. Finally, comparative assessments will be published to provide
elements for well-justified choices for the upgrades foreseen in the
three laboratories.

*[Work Package 1 : Management and Communication]{.underline}*

The following tasks are treated: oversee and coordinate the work of all
work packages, organise steering committee meetings, ensure proper
reviewing and reporting as well as dissemination of knowledge within the
JRA and the CARE project.

*[Work Package 2: Normal Conducting Accelerating
Structures]{.underline}*

Normal conducting RF structures are good candidates for beam
acceleration in a pulsed proton linac, up to an energy exceeding 100
MeV. This is especially true if this is the final energy, as in the case
of the three foreseen upgrades, because investment in cryogenic
infrastructure can be avoided. The CERN accelerator has the additional
requirement to be able, with a high duty factor (14 %), to deliver a
beam quality that is adequate for a cascaded high energy superconducting
linac (no halo). Such differences lead to different choices of RF
structures and beam dynamics, which have to be developed in parallel and
experimentally compared to help optimise the designs. In the case of
CERN, a classical beam dynamics is considered, and the types of
structures considered are DTL (Alvarez) for the energy range from 3 to
40 MeV, Coupled Cavity Drift Tube Linac (CCDTL) for 40 to 100 MeV and
probably Side Coupled Linac (SCL) above 100 MeV. Design, construction
and test of prototypes are planned, to validate the technological
choices and help select the economical optimum. For the GSI linac with a
final energy of approximately 70 MeV, the "KONUS" beam dynamics is
foreseen, with the use of H-mode structures over all the range of
energies. Low power model cavities have to be built and measured, and a
prototype 352 MHz CH cavity is proposed to be built and tested in a high
power test stand at GSI or at CERN. Simultaneous development of these
complementary structures in a single JRA will result in an optimum use
of the existing infrastructure (high power RF test places, computer
codes, etc.), an enlargement of the knowledge accessed by every
individual contributor, and finally in a better justified choice of
technological solutions in any future realisation.

*[Work Package 3: Superconducting Accelerating Structures]{.underline}*

Superconducting (SC) RF cavities have much larger efficiency,
accelerating gradient and bore aperture than normal conducting (NC)
structures. This technology is then expected to be advantageous in a
linac in terms of power consumption, construction cost and beam loss.
Although this conclusion is well accepted for the high energy part of
the accelerator, this is not the case at low energy, mostly because of
the short distance required between transverse focusing magnets, which
reduces the energy gain per real estate meter. On top of that, the
Lorentz-force-induced detuning, which modulates the accelerating field
in phase and amplitude, becomes larger as the lower energy. This effect
has to be particularly taken into account in the case of a pulsed linac,
because of the dynamic nature of the induced perturbations and of the
possibility of exciting mechanical modes. It is therefore of high
importance to improve the knowledge on the comparative performance of SC
versus NC accelerating structures to help determine the lowest energy at
which low beta superconducting cavities could safely and economically
operate.

The associated critical component, required for any high intensity
accelerating structure, is the input power coupler. The RF peak power
transferred to the beam is typically 500 kW with duty cycles of the
order of 10%, resulting also in a high average power. The peak power
limitations come mainly from multipactoring and outgassing and are very
frequency dependent. Couplers have to be tested up to 1 MW of forward
peak power for reliability issues. High power couplers are also being
developed in JRA2-WP2 for the needs TESLA but at much lower duty cycle
and higher frequency. Tight links between both JRAs will be established
to share the construction technology.

Three types of 700 MHz elliptical cavities will be tested in existing
vertical cryostats at low power, and two of them in existing horizontal
cryostats at full power. In the last test, the cavities will be fully
equipped, housed in a helium tank, with tuning system and power coupler.
There is presently no test site in Europe equipped with a 700 MHz high
power RF source in the MW range. In the frame of this JRA, we propose to
realise such a test stand at Saclay, and to make it available to the
partners in HIPPI and later to any other interested European teams.

In parallel, two alternative cavity designs at 352 MHz will be analysed.
Testing of two spoke-type cavities (two-gaps and multigap) is foreseen
at low power, and possibly at high power, depending on the availability
of a suitable infrastructure. A prototype of the tuning system for a CH
resonator will built and tested.

*[Work Package 4: Beam Chopping]{.underline}*

The next generation of high energy, high power proton accelerators must
be designed for very low uncontrolled beam loss. In many cases, the beam
from a linac is injected into a synchrotron, an accumulator or a
compressor ring, and subsequently extracted. Unless suitable measures
are taken to control the dynamics of the beam, both processes can lead
to considerable particle loss. Loss-free injection and longitudinal
capture can be achieved if the linac bunches are precisely injected
inside the synchrotron buckets and no particles end-up outside. Beam
loss at extraction may be minimised by ensuring that no circulating beam
coincides with the field rise-time of the extraction magnet. These
demands may be met by selective elimination of sets of bunches in the
low energy stages of the linac by using a fast deflector or "beam
chopper". The field should rise and fall between the beam bunch
interval, so that no partially chopped bunches remain in the machine,
and this usually has to be within a period of the order of 2 ns.

Specifications for these key components are technically challenging, and
programmes have been implemented at CERN and CCLRC-RAL based on the
development of slow wave (E-field) transmission line structures and
high-voltage, fast-transition time pulse generators. Differences in the
programmes ensure that a range of ideas will be investigated and there
will be benefits from developing each in parallel over similar
timescales. Both approaches rely on two successive sets of meander-line
structures, but differ in the functioning of the meander lines, in the
performance requirements of the driver amplifiers and in the design of
the beam dumps. Prototypes of the slow-wave structures, drivers and the
beam dumps will be designed, built and tested with beam.

*[Work Package 5: Beam Dynamics]{.underline}*

Recent studies with high intensity beams have shown that phenomena
associated with space charge and beam loss have significant impact on
the design of high power proton accelerators. In linacs, beam loss is
associated largely with the appearance of a beam halo, which needs to be
modelled theoretically and by simulation; it requires appropriate
diagnostics and must be collimated to protect the equipment and avoid
activation beyond tolerated limits. The joint activity proposed in this
work package, combines resources available at the participating
accelerator laboratories and universities for the analysis of the
following issues:

1.  Validation and Benchmarking of Simulation Codes. The development of
    adequate 3D computer codes and the proper modelling of
    self-interaction by space charge is a crucial issue. Codes must be
    fast enough to allow large ensembles of particles in order to
    resolve very small loss fractions. Including the effect of errors
    jointly with space charge requires a significant enhancement of
    simulation capabilities. Benchmarking of computer simulation codes
    against each other and against analytical models will increase the
    level of confidence in their results. Strategies to minimize halo
    formation should result from these efforts.

2.  Experiments on Beam Halo and Emittance Growth. So far, no conclusive
    experiments on beam halo in high intensity accelerators exist; hence
    this issue has highest priority. Beam experiments are proposed at
    CERN, CCLRC-RAL and GSI, where operational conditions, available
    intensities and diagnostics allow relevant measurements. Their
    interpretation by means of simulation programs should reveal the
    adequacy of theoretical and simulation approaches and the methods
    proposed to minimize beam halo and loss.

3.  Diagnostics. The acceleration and transport of high power beams also
    present new challenges for beam diagnostics. While conventional
    methods continue to be needed, operating conditions at high
    intensity require modification. New measurement techniques are
    needed to diagnose the small fractional beam losses, which could
    cause serious damage to components and produce unacceptable levels
    of activation. Monitors for direct beam halo measurements must be
    designed, constructed and tested in existing machines.

4.  Beam Collimation. Scrapers are needed to localize beam losses in
    areas designed for that purpose. Injection into rings, where much
    less aperture is available than in linacs (in particular
    superconducting linacs), requires highly effective collimators prior
    to injection. Such schemes should be designed based on simulation
    data and tested in experiments.

1.2.1 Multi-annual implementation plan

The enclosed Gantt chart presents the general planning by trimester over
the period 2005-2008 for each of the Work Packages. Milestones and
deliverables are included. The following Pert diagrams shows the
interconnections between the tasks.

![](media/image2.wmf){width="9.0in" height="6.600694444444445in"}

![](media/image3.wmf){width="9.125in" height="6.855555555555555in"}

![](media/image4.wmf){width="6.30625in" height="9.005555555555556in"}

![](media/image5.wmf){width="9.375in" height="6.023611111111111in"}1.2.2
Detailed implementation plan (Gantt chart) for the first 18 months:

![](media/image6.wmf){width="9.5in" height="5.939583333333333in"}

2\. [Quality of the management]{.smallcaps}

1.  Management and competence of the participants

    1.  Management structure

Each Work Package has a coordinator. The JRA itself is managed by a
coordinator and his deputy, who lead a steering group composed of the
Work Package coordinators (see Table 2.1.1). This steering group meets
every three months..

Table 2.1.1.: HIPPI management structure

  ------------- --------------------------------------- -------- ----------
  JRA           R. Garoby                                        
  coordinator                                                    

  Deputy        M. Vretenar                                      

                                                                 

  Work Package  Full name                               Short    Leader
                                                        name     

  WP1           Management and Communication            M&C      R. Garoby

  WP2           Normal Conducting Accelerating          NC       J.M. De
                Structures                                       Conto

  WP3           Superconducting Accelerating Structures SC       S. Chel

  WP4           Beam Chopping                           CHOP     A.
                                                                 Lombardi

  WP5           Beam Dynamics, Codes, Diagnostics and   BD       I. Hofmann
                Collimation                                      
  ------------- --------------------------------------- -------- ----------

Inside each Work Package, an annual meeting, in the form of a workshop,
is foreseen to exchange and debate information between the participants.
At the level of the JRA, a general meeting will be organised every year
in autumn, with presentations on the main research topics. The annual
report for the JRA will be published within 3 months after this event,
at the beginning of the following year.

An External Scientific Advisory Committee (ESAC) will be asked to assess
the progress of the various tasks and to help set up plans for the
future. This committee will also help establish links with similar
development programmes outside of the CARE community. Made up of 3
experts, it will participate in the annual meeting of the JRA and base
its recommendations on the presentations made at that occasion.

The total effort to be invested during 5 years in the management of
HIPPI is estimated to be of the order of 5 person-years.

The different teams involved and their relations are illustrated in the
following synoptic.

![](media/image7.wmf)

2.1.2 Role and expertise of participants

Table 2.1.2a illustrates the participation of the different institutes
in the work packages as well as the degree of integration.

Table 2.1.2a: Work Package participation

  ------------------ ---------- ---------- ---------- ---------- ----------
  Participant        WP1: M&C   WP2: NC    WP3: SC    WP4: CHOP  WP5: BD

  CCLRC-RAL                     X                     X          X

  CEA                X          X          X                     X

  CERN               X          X                     X          X

  FZJ                                      X                     X

  GSI                X                                           X

  IAP-FU                        X          X                     X

  INFN-Mi                                  X                     X

  CNRS-IN2P3-Orsay                         X                     

  CNRS-LPSC          X          X          X          X          X
  ------------------ ---------- ---------- ---------- ---------- ----------

Table 2.1.2b shows the involvement of each laboratory in the different
Work Packages and tasks, together with an estimate of their total
contribution to the activity in person-months over the 5 years. The
additional manpower support expected from the Community is included.

Table 2.1.2b : Involvement of participants

  ----------------- ------------------ -------------------------------------- ----------
  **Participant**   **WP/Topic**       **Roles**                              **Person
                                                                              month**

  CCLRC             WP2/DTL            Beam dynamics design                   72

                    WP4/Chopper B      Design and test of prototype of        96
                                       chopper structure and driver, 2 ns     
                                       rise time, 1 kV                        

                    WP5/Development    3D code development, parallelisation,  30
                                       optimisation                           

                    WP5/Benchmarking   Comparison of codes                    6

                    **TOTAL**          *Permanent staff 120, temporary staff  **204**
                                       84 persons·month*                      

  CEA               WP2/DTL            Design and construction of cold model, 80
                                       quadrupoles and alignment system. RF   
                                       measurements                           

                    WP2/CCDTL          Measurements                           2

                    WP3/Elliptical     Construction alternate cavity and      84
                                       coupler, construction and operation of 
                                       the 700 MHz test stand, tests.         

                    WP4/Chopper line   Beam measurements                      2

                    WP5/Development    Transport in 3D map, space charge      30
                                       compensation                           

                    WP5/Benchmarking   Comparison of codes                    10

                    WP5/Experiments    Participation to the measurements at   2
                                       CERN                                   

                    **TOTAL**          *Permanent staff 162, temporary staff  **210**
                                       48 persons·month*                      
  ----------------- ------------------ -------------------------------------- ----------

  ----------------- ------------------ -------------------------------------- ----------
  **Participant**   **WP/Topic**       **Roles**                              **Person
                                                                              month**

  CERN              WP2/DTL            Design of cold model, measurements     20

                    WP2/SCL            Design of model, measurements          4

                    WP2/CCDTL          Design of model, measurements          60

                    WP4/Chopper A      Design and test of pre-prototype and   36
                                       full prototype of chopper structure    
                                       and driver, 2 ns rise time, 500 V      

                    WP5/Development    Code preparation for 3 MeV test stand  18

                    WP5/Benchmarking   Comparison of codes                    18

                    WP5/Experiments    Simulations and measurements at 3 MeV  12
                                       test stand                             

                    WP5/Diagnostics    Halo measurement device                24

                    WP5/Collimation    Collimator for 3 MeV line              24

                    **TOTAL**          *Permanent staff 144, temporary staff  **216**
                                       72 persons·month*                      

  FZJ               WP3/Spoke          Evaluation of 700 MHz prototype,       117
                                       design construction and testing of a   
                                       352 MHz b 0.48 prototype               

                    WP5/Development    Codes preparation for SC linacs        60

                    WP5/Benchmarking   Comparison of codes                    

                    WP5/Diagnostics    Beam profile monitor for space charge  
                                       dominated beams                        

                    **TOTAL**          *Permanent staff 150, temporary staff  **177**
                                       27 persons·month*                      

  GSI               WP5/Development    Improvement to codes, modelling of     33
                                       high current                           

                    WP5/Benchmarking   Comparison of codes                    60

                    WP5/Experiments    Simulation and beam experiment at      93
                                       UNILAC                                 

                    WP5/Diagnostics    Profile measurement by fluorescence,   48
                                       non-interceptive bunch measurement,    
                                       online transmission control            

                    **TOTAL**          *Permanent staff 66, temporary staff   **234**
                                       168 persons·month*                     

  IAP-FU            WP2/HDTL           H-DTL prototyping                      48

                    WP3/CH             Study, design,fabrication and          54
                                       measurements of a prototype tuning     
                                       system                                 

                    WP5/Development    LORASR code                            20

                    WP5/Benchmarking   Comparison of codes                    10

                    **TOTAL**          *Permanent staff 42, temporary staff   **132**
                                       90 persons·month*                      

  INFN-Mi           WP3/Elliptical     Preparation test cavity with tuners    18
                                       (fast and slow), tests                 

                    WP5/Benchmarking   Comparison of codes                    6

                    **TOTAL**          *Permanent staff 12, temporary staff   **24**
                                       12 persons·month*                      
  ----------------- ------------------ -------------------------------------- ----------

  ------------------ ------------------ -------------------------------------- ---------
  CNRS-IN2P3-Orsay   WP3/Spoke          Evaluation of 2-gaps 352 MHz           40
                                        prototypes, design and construction of 
                                        coupler & tuner, test of multi-gaps    
                                        prototype                              

                     **TOTAL**          *Permanent staff 32, temporary staff 8 **40**
                                        persons·month*                         

  CNRS-LPSC          WP2/DTL            Design of cold model, measurements     40

                     WP2/SCL            Design of model, measurements          48

                     WP2/CCDTL          Design of model, measurements          2

                     WP3/Elliptical     Contribution to cavity and coupler     24
                                        design                                 

                     WP4/Chopper line   Beam measurements                      3

                     WP5/Benchmarking   Comparison of codes                    30

                     **TOTAL**          *Permanent staff 111, temporary staff  **147**
                                        36 persons·month*                      
  ------------------ ------------------ -------------------------------------- ---------

The total effort corresponds to 1384 person-months. The expertise and
relevant infrastructures of the participants are given in the Table
2.1.2c.

Table 2.1.2c: Expertise and relevant infrastructures of the participants

  ------------------ --------------------------------------------- ------------------
  **Institute**      **Specific Expertise (indicate the expertise  **Infrastructure
                     of the institute for that particular          relevant to the
                     project)**                                    project**

  CCLRC              Ion source, RFQ, chopper development.         ISIS Linac
                     Accelerator design, construction and          
                     operation. Beam dynamics studies..            

  CEA                Design and construction of superconducting RF IPHI test stand,
                     systems for linear accelerators and of        SC laboratory
                     high-intensity normal conducting linacs.      

  CERN               Design, construction and exploitation of      3 MeV test stand,
                     normal-conducting linear accelerators and     Linac2
                     related equipment. Beam dynamics developments 
                     and simulations. Beam experiments.            

  FZJ                Design of superconducting accelerating        SC laboratory
                     structures. Design of high-intensity and      
                     high-energy accelerators.                     

  GSI                Linear accelerator for ion beams of high      UNILAC
                     intensities, beam dynamics experiments &      
                     simulations, code development,                
                     non-destructive diagnostics for intense ion   
                     beams                                         

  IAP-FU             Linear accelerators development and           
                     construction, normal conducting and           
                     superconducting, beam optics developments and 
                     simulations.                                  

  INFN-Mi            Design and construction of superconducting RF SC laboratory
                     cavities. Beam dynamics developments and      
                     simulations.                                  

  CNRS-IN2P3-Orsay   Design of superconducting accelerating        
                     structures. Design of high-intensity and      
                     high-energy accelerators.                     

  CNRS-LPSC          Ion sources. Accelerator design, construction 
                     and operation. IPHI collaboration.            
  ------------------ --------------------------------------------- ------------------

Selected references

Major references are given below. A more complete list can be found on
the CARE web site.

CCLRC:

-   F. Gerigk: *Space Charge and Beam Halo in Proton Linacs*,
    US-CERN-JAPAN-RUSSIA Particle Accelerator School, Long Beach, CA,
    2002,
    <http://www.isis.rl.ac.uk/acceleratortheory/frank/publications/jas02.pdf>
    .

-   M.A. Clarke-Gayther: *A fast chopper for the ESS 2.5 MeV beam
    transport line*, Proceedings of the 2002 European Particle
    Accelerator Conference (EPAC 2002), Paris,
    <http://accelconf.web.cern.ch/AccelConf/e02/PAPERS/TUPDO005.pdf> .

-   C.R. Prior: *Computer Simulation of the Motion of Charged-Particle
    under Space Charge*. Proceedings of Workshop on Space Charge Physics
    in High Intensity Hadron Rings, Shelter Island, New York. May 1998.
    (CCLRC Report: RAL-TR-1998-048.)

CEA:

-   J.P. Charrier et al.: *700 MHz Superconducting Proton Cavities
    Development and first tests in the horizontal Cryostat
    \"CRYHOLAB\",* Proceedings of EPAC 2002, Paris,
    <http://accelconf.web.cern.ch/AccelConf/e02/PAPERS/THPDO036.pdf> .

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-   N. Pichoff: *Intrabeam Scattering on Halo Formation*, 18th Biennial
    Particle Accelerator Conference, New York City, NY, USA, 29 Mar - 2
    Apr 1999 - IEEE Computer Society Press, Piscataway, NJ, 1999 -
    <http://accelconf.web.cern.ch/AccelConf/p99/PAPERS/THP135.PDF>

-   G. Devanz, H. Safa, C. Travier: *Preliminary Design of a 704 MHz
    Power Coupler for a High Intensity Proton Linear Accelerator*,
    Proceedings of EPAC 2000, Vienna, Austria,
    <http://accelconf.web.cern.ch/AccelConf/e00/PAPERS/THP5B02.pdf>

CERN:

-   M. Vretenar (editor): *Conceptual Design of the SPL, a High-Power
    Superconducting H- Linac at CERN,* CERN 2000-12,
    [[http://preprints.cern.ch/yellowrep/2000/2000-012/p1.pdf]{.underline}](http://preprints.cern.ch/yellowrep/2000/2000-012/p1.pdf)

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```
-   F. Gerigk, M. Vretenar: *Design of a 120 MeV H- Linac for CERN
    High-Intensity Applications*, Proceedings of the LINAC 2002
    Conference, <http://linac2002.postech.ac.kr/db/proceeding/MO415.PDF>

-   F. Caspers, K. Hanke, A. Lombardi, A. Millich, A. Mostacci, M.
    Paoluzzi, M. Vretenar: *Design of a chopper line for the CERN SPL*,
    Proceedings of the LINAC 2002 Conference,

> <http://linac2002.postech.ac.kr/db/proceeding/MO416.PDF>

FZJ:

-   R. Maier et al.: *The Superconducting Injector LINAC for the
    Cooler-Synchrotron COSY at FZ-Juelich*, Proceedings of the LINAC
    2002 Conference,
    <http://linac2002.postech.ac.kr/db/proceeding/TU482.PDF>

```{=html}
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```
-   J. Dietrich, I. Mohos, F. Wenander, G. Riehl, J. Häuser: *High
    Sensitive Beam Emittance Analyzer*, Proceedings of EPAC 2002, Paris,
    <http://accelconf.web.cern.ch/AccelConf/e02/PAPERS/THPRI115.pdf> .

-   Y. Senichev et al.: *Some Features of Beam dynamics in
    super-conducting linac based on quarter- and half-wave cavities,*
    Proceedings of EPAC 2002, Paris,
    <http://accelconf.web.cern.ch/AccelConf/e02/PAPERS/WEPLE107.pdf> .

GSI:

-   P. Forck and A. Bank: *Residual Gas Fluorescence for Profile
    Measurements at the GSI UNILAC,* Proceedings of EPAC 2002, Paris,
    [[http://accelconf.web.cern.ch/AccelConf/e02/PAPERS/THPRI056.pdf]{.underline}](http://accelconf.web.cern.ch/AccelConf/e02/PAPERS/THPRI056.pdf)
    .

-   Hofmann, G. Franchetti, J. Qiang, R. Ryne, F. Gerigk, D. Jeon,
    and N. Pichoff: *Review of Beam Dynamics and Space Charge Resonances
    in High Intensity Linacs*, Proceedings of EPAC 2002, Paris,

[[http://accelconf.web.cern.ch/AccelConf/e02/PAPERS/WEYGB001.pdf]{.underline}](http://accelconf.web.cern.ch/AccelConf/e02/PAPERS/WEYGB001.pdf)
.

-   W. Barth and L. Groening: *Measurements and Simulations on the Beam
    Brilliance in the Universal Linear Accelerator UNILAC at GSI*,
    Proceedings of the LINAC 2002 Conference,
    [[http://linac2002.postech.ac.kr/db/proceeding/TU419.PDF]{.underline}](http://linac2002.postech.ac.kr/db/proceeding/TU419.PDF)

IAP-FU:

-   Sauer, R. Tiede, H. Deitinghoff, H. Klein, U. Ratzinger:
    *Investigation of a Normal Conducting 175 MHz Linac Design for
    IFMIF*, Proceedings of EPAC 2002, Paris,
    <http://accelconf.web.cern.ch/AccelConf/e02/PAPERS/THPLE059.pdf> .

-   A. Sauer, H. Deitinghoff, H. Klein, U. Ratzinger, R. Tiede, R.
    Eichhorn: *Beam Dynamics Design of a Superconducting 175 MHz
    CH-Linac for IFMIF*, Proceedings of EPAC 2002, Paris,
    <http://accelconf.web.cern.ch/AccelConf/e02/PAPERS/WEPLE081.pdf> .

-   R. Eichhorn, H. Liebermann and U. Ratzinger: *Superconducting
    CH-Cavities for Low and Medium Beta Ion and Proton Accelerators*,
    Proceedings of the LINAC 2002 Conference,
    <http://linac2002.postech.ac.kr/db/proceeding/TU471.PDF>

INFN-Mi:

-   D. Barni, A. Bosotti, C. Pagani, R. Paulon, P. Pierini, H. Safa, G.
    Ciovati, P. Kneisel: *RF Tests of the Single Cell Prototypes for the
    TRASCO =0.47 Cavities*, Proceedings of EPAC 2002, Paris, France,
    <http://accelconf.web.cern.ch/AccelConf/e02/PAPERS/THPDO023.pdf>

-   D. Barni et al.: *Status of the High Current Proton Accelerator for
    the TRASCO Program*, Proceedings of EPAC 2002, Paris, France,
    <http://accelconf.web.cern.ch/AccelConf/e02/PAPERS/THBLA002.pdf> .

-   G. Bellomo, M. Novati, P. Pierini: *Adiabatic Matching in Periodic
    Accelerating Lattices for Superconducting Proton Linacs*,
    Proceedings of EPAC 2002, Paris,
    <http://accelconf.web.cern.ch/AccelConf/e02/PAPERS/WEPLE109.pdf> .

CNRS-IN2P3-Orsay:

-   G. Olry & al.: *Study of a Spoke Cavity for Low beta Applications,*
    Proceedings of SRF2001 Workshop, September 2001, Tsukuba,
    <http://conference.kek.jp/SRF2001/pdf/MA001.pdf>

-   G. Olry & al.: *Design and Industrial Fabrication of a beta=0.35
    Spoke-type Cavity,* Proceedings of EPAC 2002, Paris,

> <http://accelconf.web.cern.ch/AccelConf/e02/PAPERS/THPDO035.pdf>

CNRS-LPSC:

-   J.M. De Conto: *GENEPI, a high intensity deuteron accelerator for
    pulsed neutron production*, Proceedings of EPAC 1998, Stockholm,
    <http://accelconf.web.cern.ch/AccelConf/e98/PAPERS/WEP08F.PDF> .

-   J.M. De Conto, C. Peaucelle: *Fundamental Aspects of the Moment
    Problem for a Particle Density evolving under Non-linear Forces*,
    Proceedings of EPAC 2002, Paris,
    <http://accelconf.web.cern.ch/AccelConf/e02/PAPERS/WEPLE080.pdf> .

-   P.-E. Bernaudin et al.: *Design of the IPHI DTL*, Proceedings of PAC
    2001, Chicago, USA,
    <http://accelconf.web.cern.ch/AccelConf/p01/PAPERS/FPAH096.PDF> .

2.2 Justification of financing requested

2.2.1 Detailed cost breakdown

Among the nine partners in the HIPPI JRA, six are using the Full Cost
model (FC) and three the Additional Cost model (AC).

To accomplish the tasks described in section 1.2, the cost per Work
Package for each contributor is given in Table 2.2.1a. Work Package 1
only covers the travel costs of the coordinators (3 per year) and of the
External Scientific Advisory Committee (3 experts invited for 2 days
every year)..

To help evaluate properly the means really invested in the course of the
HIPPI JRA, Table 2.2.1b indicates the amount of internal resources that
the institutes working under the Additional Cost model do not declare in
Table 2.2.1a. They mostly correspond to the salaries of permanent staff.

The amount expected to be spent by type of expenditure is shown in Table
2.2.1c. A preliminary profile of the requested EU funding over the 5
years of the Activity is given in Table 2.2.1d.

2.2.2 Durable equipment

The HIPPI JRA includes two durable elements that can be used after its
completion. Each of them has a cost which is lower than the internal
laboratory contribution to the JRA activities. It can be assumed that
the Community contribution will cover only the consumables, prototypes
and temporary staff, while the laboratory will cover the durable
equipments. These are:

1.  The 700 MHz high power test station at CEA-Saclay (1130 k€). A test
    station for pulsing superconducting cavities is essential to fully
    characterize the cavities developed in HIPPI, and there is none
    presently available in Europe. After the end of this JRA, it will be
    accessible to any interested institute.

2.  The beam diagnostics equipment at GSI, profile measurement and
    non-interceptive bunch measurement (110 k€). The development of
    appropriate diagnostics must go in parallel with the advance in beam
    dynamics. This device could afterwards be used in an operational
    accelerator.

Table 2.2.1a: Summary of expected costs and requested EU funding
(kEuros)

<table>
<colgroup>
<col style="width: 9%" />
<col style="width: 5%" />
<col style="width: 6%" />
<col style="width: 6%" />
<col style="width: 6%" />
<col style="width: 7%" />
<col style="width: 6%" />
<col style="width: 6%" />
<col style="width: 6%" />
<col style="width: 6%" />
<col style="width: 7%" />
<col style="width: 7%" />
<col style="width: 8%" />
<col style="width: 7%" />
</colgroup>
<tbody>
<tr class="odd">
<td>Acronym</td>
<td>Cost</td>
<td colspan="2">WP1: M&amp;C</td>
<td colspan="2">WP2: NC</td>
<td colspan="2">WP3: SC</td>
<td colspan="2">WP4: CHOP</td>
<td colspan="2">WP5: BD</td>
<td colspan="2"><p id="total" class="heading">Total</p></td>
</tr>
<tr class="even">
<td> </td>
<td>Model</td>
<td>Exp. Cost</td>
<td>Req. Cost</td>
<td>Exp. Cost</td>
<td>Req. Cost</td>
<td>Exp. Cost</td>
<td>Req. Cost</td>
<td>Exp. Cost</td>
<td>Req. Cost</td>
<td>Exp. Cost</td>
<td>Req. Cost</td>
<td>Exp. Cost</td>
<td>Req. Cost</td>
</tr>
<tr class="odd">
<td><strong>CCLRC</strong></td>
<td><strong>FC</strong></td>
<td><strong>0</strong></td>
<td><strong>0</strong></td>
<td><strong>855</strong></td>
<td><strong>200 </strong></td>
<td><strong>0</strong></td>
<td><strong>0 </strong></td>
<td><strong>1 663</strong></td>
<td><strong>200 </strong></td>
<td><strong>614</strong></td>
<td><strong>65 </strong></td>
<td><strong>3 132</strong></td>
<td><strong>465</strong></td>
</tr>
<tr class="even">
<td><strong>CEA</strong></td>
<td><strong>FC</strong></td>
<td><strong>11</strong></td>
<td><strong>11</strong></td>
<td><strong>684</strong></td>
<td><strong>119 </strong></td>
<td><strong>2 715</strong></td>
<td><strong>800 </strong></td>
<td><strong>0</strong></td>
<td><strong>0 </strong></td>
<td><strong>425</strong></td>
<td><strong>50 </strong></td>
<td><strong>3 835</strong></td>
<td><strong>980</strong></td>
</tr>
<tr class="odd">
<td><strong>CERN</strong></td>
<td><strong>AC</strong></td>
<td><strong>65</strong></td>
<td><strong>65</strong></td>
<td><strong>770</strong></td>
<td><strong>340 </strong></td>
<td><strong>0</strong></td>
<td><strong>0 </strong></td>
<td><strong>400</strong></td>
<td><strong>130 </strong></td>
<td><strong>300</strong></td>
<td><strong>100 </strong></td>
<td><strong>1 535</strong></td>
<td><strong>635</strong></td>
</tr>
<tr class="even">
<td><strong>FZJ</strong></td>
<td><strong>FC</strong></td>
<td><strong>0</strong></td>
<td><strong>0</strong></td>
<td><strong>0</strong></td>
<td><strong>0 </strong></td>
<td><strong>1 580</strong></td>
<td><strong>365 </strong></td>
<td><strong>0</strong></td>
<td><strong>0 </strong></td>
<td><strong>695</strong></td>
<td><strong>162 </strong></td>
<td><strong>2 275</strong></td>
<td><strong>527</strong></td>
</tr>
<tr class="odd">
<td><strong>GSI</strong></td>
<td><strong>FC</strong></td>
<td><strong>16</strong></td>
<td><strong>11</strong></td>
<td><strong>0</strong></td>
<td><strong>0 </strong></td>
<td><strong>0</strong></td>
<td><strong>0 </strong></td>
<td><strong>0</strong></td>
<td><strong>0 </strong></td>
<td><strong>1 665</strong></td>
<td><strong>352 </strong></td>
<td><strong>1 681</strong></td>
<td><strong>363</strong></td>
</tr>
<tr class="even">
<td><strong>IAP-FU</strong></td>
<td><strong>AC</strong></td>
<td><strong>0</strong></td>
<td><strong>0</strong></td>
<td><strong>436</strong></td>
<td><strong>180 </strong></td>
<td><strong>385</strong></td>
<td><strong>165 </strong></td>
<td><strong>0</strong></td>
<td><strong>0 </strong></td>
<td><strong>183</strong></td>
<td><strong>75 </strong></td>
<td><strong>1 004</strong></td>
<td><strong>420</strong></td>
</tr>
<tr class="odd">
<td><strong>INFN-Mi</strong></td>
<td><strong>AC</strong></td>
<td><strong>0</strong></td>
<td><strong>0</strong></td>
<td><strong>0</strong></td>
<td><strong>0 </strong></td>
<td><strong>190</strong></td>
<td><strong>77 </strong></td>
<td><strong>0</strong></td>
<td><strong>0 </strong></td>
<td><strong>3</strong></td>
<td><strong>3 </strong></td>
<td><strong>193</strong></td>
<td><strong>80</strong></td>
</tr>
<tr class="even">
<td><em>CNRS-IN2P3-Orsay</em></td>
<td><em>FC</em></td>
<td><em>0</em></td>
<td><em>0</em></td>
<td><em>0</em></td>
<td><em>0</em></td>
<td><em>272</em></td>
<td><em>70</em></td>
<td><em>0</em></td>
<td><em>0</em></td>
<td><em>0</em></td>
<td><em>0</em></td>
<td><em>272</em></td>
<td><em>70</em></td>
</tr>
<tr class="odd">
<td><em>CNRS-LPSC</em></td>
<td><em>FC</em></td>
<td><em>11</em></td>
<td><em>11</em></td>
<td><em>490</em></td>
<td><em>46 </em></td>
<td><em>120</em></td>
<td><em>0 </em></td>
<td><em>15</em></td>
<td><em>0 </em></td>
<td><em>170</em></td>
<td><em>3 </em></td>
<td><em>806</em></td>
<td><em>60</em></td>
</tr>
<tr class="even">
<td><strong>CNRS total</strong></td>
<td><strong>FC</strong></td>
<td><strong>11</strong></td>
<td><strong>11</strong></td>
<td><strong>490</strong></td>
<td><strong>46</strong></td>
<td><strong>392</strong></td>
<td><strong>70</strong></td>
<td><strong>15</strong></td>
<td><strong>0</strong></td>
<td><strong>170</strong></td>
<td><strong>3</strong></td>
<td><strong>1 078</strong></td>
<td><strong>130</strong></td>
</tr>
<tr class="odd">
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td><strong>14 733</strong></td>
<td><strong>3 600</strong></td>
</tr>
</tbody>
</table>

2.2.1b: Internal cost not accounted for in Table 2.2.1a for participants
using the AC model (kEuros)

  ---------------------------------- ------------------------------------
  **Acronym**                        **Cost Contribution**

  CERN                               1 350

  IAP-FU                             288

  INFN-Mi                            47

  **Total**                          **1 685**
  ---------------------------------- ------------------------------------

Table 2.2.1c: Costs per participant

<table>
<colgroup>
<col style="width: 18%" />
<col style="width: 8%" />
<col style="width: 8%" />
<col style="width: 8%" />
<col style="width: 8%" />
<col style="width: 8%" />
<col style="width: 8%" />
<col style="width: 8%" />
<col style="width: 8%" />
<col style="width: 8%" />
<col style="width: 8%" />
</colgroup>
<tbody>
<tr class="odd">
<td>Laboratory</td>
<td>CCLRC-RAL</td>
<td>CEA</td>
<td>CERN</td>
<td>FZJ</td>
<td>GSI</td>
<td>IAP-FU</td>
<td>INFN-Mi</td>
<td><em>CNRS-IN2P3-Orsay</em></td>
<td><em>CNRS-LPSC</em></td>
<td>CNRS total</td>
</tr>
<tr class="even">
<td>Cost model</td>
<td>FC</td>
<td>FC</td>
<td>AC</td>
<td>FC</td>
<td><h6 id="fc">FC</h6></td>
<td>AC</td>
<td>AC</td>
<td><em>FC</em></td>
<td><em>FC</em></td>
<td>FC</td>
</tr>
<tr class="odd">
<td>Durable equipment</td>
<td>0</td>
<td>1 065</td>
<td>0</td>
<td>0</td>
<td>110</td>
<td>0</td>
<td>0</td>
<td><em>0</em></td>
<td><em>0</em></td>
<td>0</td>
</tr>
<tr class="even">
<td>Consumables &amp; prototypes</td>
<td>550</td>
<td>924</td>
<td>660</td>
<td>245</td>
<td>0</td>
<td>450</td>
<td>123</td>
<td><em>130</em></td>
<td><em>55</em></td>
<td>185</td>
</tr>
<tr class="odd">
<td>Temporary Staff</td>
<td>788</td>
<td>200</td>
<td>810</td>
<td>304</td>
<td>680</td>
<td>540</td>
<td>40</td>
<td><em>15</em></td>
<td><em>65</em></td>
<td>80</td>
</tr>
<tr class="even">
<td>Permanent Staff</td>
<td>1 779</td>
<td>1 635</td>
<td><em>/</em></td>
<td>1 696</td>
<td>865</td>
<td><em>/</em></td>
<td><em>/</em></td>
<td><em>120</em></td>
<td><em>675</em></td>
<td>795</td>
</tr>
<tr class="odd">
<td>Travels</td>
<td>15</td>
<td>11</td>
<td>65</td>
<td>30</td>
<td>26</td>
<td>14</td>
<td>30</td>
<td><em>7</em></td>
<td><em>11</em></td>
<td>18</td>
</tr>
<tr class="even">
<td><strong>Total</strong></td>
<td><strong>3 132</strong></td>
<td><strong>3 835</strong></td>
<td><strong>1 535</strong></td>
<td><strong>2 275</strong></td>
<td><strong>1 681</strong></td>
<td><strong>1 004</strong></td>
<td><strong>193</strong></td>
<td><em>272</em></td>
<td><em>806</em></td>
<td><strong>1 078</strong></td>
</tr>
<tr class="odd">
<td><strong>Requested contribution</strong></td>
<td><strong>465</strong></td>
<td><strong>980</strong></td>
<td><strong>635</strong></td>
<td><strong>527</strong></td>
<td><strong>363</strong></td>
<td><strong>420</strong></td>
<td><strong>80</strong></td>
<td><em>70</em></td>
<td><em>60</em></td>
<td><strong>130</strong></td>
</tr>
</tbody>
</table>

Table 2.2.1d: Preliminary profile of requested EU funding over JRA
duration

  -------------------- ---------- ---------- ---------- ---------- ---------- -----------
                       **2004**   **2005**   **2006**   **2007**   **2008**   **Total**

  **CCLRC**            **84**     **88**     **93**     **97**     **103**    **465**

  **CEA**              **210**    **240**    **480**    **48**     **2**      **980**

  **CERN**             **80**     **150**    **195**    **150**    **60**     **635**

  **FZJ**              **90**     **140**    **160**    **100**    **37**     **527**

  **GSI**              **130**    **80**     **100**    **40**     **13**     **363**

  **IAP-FU**           **75**     **141**    **132**    **36**     **36**     **420**

  **INFN-Mi**          **20**     **20**     **30**     **8**      **2**      **80**

  *CNRS-IN2P3-Orsay*   *5*        *10*       *20*       *20*       *15*       *70*

  *CNRS-LPSC*          *2*        *20*       *30*       *6*        *2*        *60*

  **CNRS total**       **7**      **30**     **50**     **26**     **17**     **130**

  **Total**            **696**    **898**    **1249**   **499**    **258**    **3600**
  -------------------- ---------- ---------- ---------- ---------- ---------- -----------

3\. [European added value]{.smallcaps}

**3.1 Interest for European research infrastructures and their users**

The R&D effort in HIPPI will be the basis for improvements at three
major European laboratories, broadening at the same time their potential
for physics and the size of the interested scientific community.

These upgrade programmes pursue different and complementary goals:

-   Neutrino physics (represented in CARE by the NA3): the community has
    shown a substantial interest in the proposed upgrades at CCLRC-RAL
    and CERN \[1\]. With the support of ECFA, a series of workshops
    ("NuFact"), started in Lyon in 1999, has since taken place every
    year in various places around the world. The proton driver is an
    important subject, addressed at each occasion, where progress is
    eagerly expected.

-   Radioactive ion physics: the ISOLDE experiments at CERN would
    immediately benefit from the higher proton flux from an improved
    injector \[2\]. Furthermore, the EURISOL study \[3\], supported by
    NuPECC, has shown that the next generation facility using the
    Isotope on line separation technique needs a two orders of magnitude
    larger proton flux. The upgrades considered in the HIPPI JRA could
    constitute a first step towards the necessary proton driver.

-   Spallation Neutron sources: since the interruption of the ESS
    project, this programme is now continuing mainly as an upgrade of
    the ISIS facility at CCLRC-RAL \[4\].

-   Upgrade of the Large Hadron Collider (represented in CARE by NA3 and
    JRA5): the upgrade of the CERN injector complex is a logical first
    step towards a performance upgrade of the LHC \[5\].

Considering the magnitude of the resources that the European countries
have already devoted to the construction of the CERN, GSI and CCLRC-RAL
complex of accelerators, these improvements would significantly increase
their potential value for physics research in the future for a marginal
additional cost.

**3.2 Exploitation of results**

The results of the HIPPI JRA will consist in the development of new
technologies for the design and construction of high intensity pulsed
linear accelerators. The prototypes, the calculation tools and more
generally the expertise developed in this frame will be the basis for
the design and construction of the next generation of accelerators in
Europe. They will be exploited in priority by the three laboratories
interested in upgrading their accelerator complex.

However, the outcomes of HIPPI will not be patented, and according to
the policy of the partner institutions, will be available to the
scientific community and to industrial companies interested in
accelerators for technological applications (generation of
radio-isotopes for medicine, biology ...).

The reports produced in the frame of HIPPI will be referenced and will
be accessible through the scientific information distribution system of
the partner laboratories. Part of the reports, integrally or in a
condensed form, will be published in scientific journals and in the
proceedings of international conferences.

**3.3 Risk assessment**

*[Monitoring success]{.underline}*

The specifications to be met by the various prototypes will be defined
at the general meeting of HIPPI in the autumn 2004, with the approval of
the External Scientific Advisory Committee. The ambition is to surpass
the performance of the machines presently under construction in the US
or in Japan. Success will be measured by the degree at which these
technical goals are met. An important parameter to evaluate the
technical solutions will be their cost, which has to be smaller or equal
(for a better performance) to that of the previous generation of
European linear accelerators.

The most challenging goals are summarized as follows:

1.  in WP2 (normal-conducting accelerating structures): development of
    high-current structures less expensive than conventional DTL's,
    while keeping a shunt impedance ZT^2^ (power efficiency) higher than
    40 M/m in the energy range 20-100 MeV. At lower energy (3-20 MeV),
    the challenge is to develop a low cost DTL design.

2.  in WP3 (superconducting accelerating structures): development of
    structures that reach a gradient exceeding 7 MV/m with Q 10^10^ in
    the energy range 100-200 MeV, at a construction cost comparable to
    normal-conducting structures.

3.  in WP4 (chopping): development of a chopping set-up (chopper and
    chopper-line) leaving no partially filled buckets \[switching time
    smaller than the distance between bunches at 352 MHz (CERN goal) or
    280 MHz (RAL goal), limited overshoot and ringing, ...\]. Moreover,
    the overall design of the chopper-line has to minimize emittance
    growth.

4.  in WP5 (beam dynamics): experimental validation of simulation codes,
    and rules for a beam optics design, including collimators and
    appropriated diagnostics tools, capable of keeping the uncontrolled
    beam loss below the threshold for hands-on maintenance (1 W/m) all
    along a high energy linac (\> 1 GeV) and the associated transfer
    lines.

*[Impact]{.underline}*

Apart from the three foreseen accelerator upgrades in Europe, it is
foreseeable that the outcome of the HIPPI JRA will become a reference
for the next projects elsewhere in world. Other impact will include the
education of young scientists in the field of accelerator technology and
the reinforcement of links between European institutions.

*[Risk]{.underline}*

The general approach of the HIPPI JRA is to develop in parallel
different technologies of diverse complexity and/or innovative content,
with the aim of finally providing comparative assessments. Since it is
very unlikely that all approaches will fail simultaneously, the risk of
complete failure is very low. Using the definitions given in Table 3.3a,
the list of tasks with an associated risk are listed in Table 3.3b. In
each case, a corrective action is indicated as well as the consequences
on the project.

Table 3.3a : Definition of risk levels

  ---------- ------------------------------------------------------------
  Risk Level Meaning

  RL1        [Low Risk]{.underline}: minor error might happen, could be
             easily corrected since no technical challenge is involved.
             Scope of the project is unchanged. Minor impact on schedule
             (\<3 months) or cost (\<5%) might be necessary.

  RL2        [Medium Risk]{.underline}: A small downgrading of the final
             objectives might be required. Alternatively a small delay
             (\<1 year) and cost increase might be necessary (\<20%) to
             maintain the initial objectives.

  RL3        [High Risk]{.underline}: Significant downgrading of the
             objectives might be required. Alternatively more R&D, more
             time (\>1 year) and more money (\>20%) would be required.
  ---------- ------------------------------------------------------------

Table 3.3b : Risk assessment

  ---- ------------ ---------------------- ---------------------- ------- --------------
  WP   Topic        Risk                   Action                 Level   Consequence

  1    DTL          One or more of the     Add more time for      1       Delay / Extra
                    proposed design        development or revert          cost for
                    improvements do not    to standard                    construction
                    work                   construction technique         
                                           (CERN Linac2)                  

  1    HDTL         The prototype presents Revert to other        1       Extra cost for
                    tuning/cooling         structures requiring           construction
                    problems or does not   more RF Power (DTL,            
                    have the design        CCDTL, SCL)                    
                    efficiency                                            

  1    SCL          Not able to tune the   New cold model with    1       Delay to 12/08
                    cold model             revised design                 

  1    CCDTL        The prototype presents Revert to a DTL        1       Extra cost for
                    tuning/cooling         design, requiring more         construction
                    problems               RF power                       

  2    Elliptical   A satisfactory         If the other SC        1       None
                    gradient under pulsed  developments fail,             
                    tests is not achieved  adopt a normal                 
                    by end 2008            conducting design for          
                                           all the linac                  

  2    Spoke        A satisfactory         If the other SC        1       None
                    gradient is not        developments fail,             
                    achieved by end 2008   adopt a normal                 
                                           conducting design for          
                                           all the linac                  

  2    CH           Problems in cooling or If the other SC        1       None
                    in achieving a         developments fail,             
                    satisfactory gradient  adopt a normal                 
                                           conducting design for          
                                           all the linac                  

  3    Chopper A    Prototype not          If also chopper B      2       Degradation of
                    achieving specified    fails: accept some             machine
                    rise time or voltage   loss level in the              performance
                                           machine                        

  3    Chopper line Emittance growth       Accept some loss level 2       Degradation of
                    and/or beam loss       in the machine                 machine
                    measured in chopper                                   performance
                    line                                                  

  3    Chopper line Chopper dump prototype Limit operation to low 1        
                    performance not to     duty cycle (\<1%)              
                    specifications                                        

  3    Chopper B    Prototype not          If also chopper A      2       Degradation of
                    achieving specified    fails: accept some             machine
                    rise time or voltage   loss level in the              performance
                                           machine                        

  4    Simulation   Failure of the codes   Accept some loss level 2       Degradation of
       codes        to represent measured  in the machine                 machine
                    parameters at the test                                performance
                    stand                                                 

  4    Beam         Diagnostics not ready  Additional development 1       Delay ( \~1
       experiment   in time, not providing required                       year)
                    the required                                          
                    resolution                                            
  ---- ------------ ---------------------- ---------------------- ------- --------------

REFERENCES (section 3)

\[1\] Web-site for "Neutrino Factory and Muon storage rings at CERN",
<http://muonstoragerings.web.cern.ch/muonstoragerings/>

\[2\] M. Lindroos: *Future Plans at ISOLDE,* 14th International
Conference on Electromagnetic Isotope Separators and Techniques related
to their Application, 6-10 May, 2002, Victoria, BC,

Canada,
<http://doc.cern.ch/archive/electronic/cern/preprints/ps/ps-2002-047.pdf>

\[3\] Web-site of the EURISOL study,
<http://www2.ganil.fr/eurisol/index.html>

\[4\] Web-site of the ESS study, <http://www.ess-europe.de/en/index.php>

\[5\] LHC Luminosity and energy upgrade : A Feasibility Study **/** O.
Bruning et al.\
CERN-LHC-Project-Report-626 ; LHC-Project-Report-626. - Geneva : CERN ,
1 Dec 2002. - 98 p. -
[Fulltext](http://documents.cern.ch/cgi-bin/setlink?base=preprint&categ=cern&id=lhcproj-2003-626)