proton driver activities @ saclay

BENE 17/03/05 1C. Cavata

Proton driver Proton driver activitiesactivities @ Saclay @ SaclayA talk assembled with materials from• R. Gobin• P.Y. Beauvais• B. Visentin• R. Duperrier

OutlinesA. ECR H- sourceB. NC RFQC. SuperConducting CavitiesD. Code/Simulation of Space

Charge

C. Cavata BENE 17/03/05 2

Proton LINAC : Overall DesignProton LINAC : Overall Design

High Energy

SuperConducting Elliptical Cavities

(5-cell 704 MHz)

I njector

(352 MHz)

I ntermediateAcceleration

SC or NCResonators

500

MeV 600 MeV XADS

200

MeV

100

MeV

5M

eV

100

keV

SOURCE RFQ CH - DTL orQWR - Spoke

LowBeta=0.47

Medium Beta=0.65

High Beta=0.85

1-2 GeV EURI SOL

High Energy


(5-cell 704 MHz)

I njector

(352 MHz)


SC or NCResonators

500

MeV 600 MeV XADS

200

MeV

100

MeV

5M

eV

100

keV


LowBeta=0.47

Medium Beta=0.65

High Beta=0.85

1-2 GeV EURI SOL

High Energy


(5-cell 704 MHz)

High Energy


(5-cell 704 MHz)

I njector

(352 MHz)


SC or NCResonators

500

MeV 600 MeV XADS

200

MeV

100

MeV

5M

eV

100

keV


LowBeta=0.47

Medium Beta=0.65

High Beta=0.85

1-2 GeV EURI SOL

I njector

(352 MHz)


SC or NCResonators

500

MeV 600 MeV XADS

200

MeV

100

MeV

5M

eV

100

keV


LowBeta=0.47

Medium Beta=0.65

High Beta=0.85

1-2 GeV EURI SOL

SPLEUROTRANS

CW or Pulsed LINAC

Niobium Superconducting

Cavities

Spoke Elliptical

QWR


Proton Driver Activities

@ Saclay

H- Electron Cyclotron Resonance Source


Rectangular plasma chamber5 mm extraction apertureECR zone at RF entranceOperation : Pulsed modeEnergy 10 kV

Technical options

A new source based on ECR plasma

A 2.5 GHz designMain Goal is reliability

Aim : for high power accelerators, H- current of a few tens of mA at 50 to 100

kV

A new H- source based on ECR plasma


H- production

A/ Plasma H2 → H+ + e- ; H2+e- (a few 10 eV) → H2*+e-

B/ Dissociation H2*+e- (eV) → H-+H

Installation of a stainless steel grid in the rectangular plasma chamber


Grid position

I H- from few µA to nearly 100 µA

Grid polarization

I H- from 100 µA to nearly 1mA

First Optimisati

ons:

H- production


H- gain confirmation

To prove effective H- ions productionanalysis with a dipole magnet

?


0 2 4 6 8 10 12

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

Coura

nt d

'ions

H- (m

A)

Tension d'extraction (kV)

courant d'ion H- avec un paque de nitrure de Boresous une pression de 3.2 mTorr

latest results

the extracted H- current increased up to 1.25 mA at 10kV.

And after parameter optimisations, the extracted

beam reached close to 4 mA at 10kV .

Reflected RF powerH- beam, 0.5mA/cc

and 0.5ms/cc

The source is running at lower pressure

To increase the e- density in the plasma generator zone, Boron Nitride plates have been installed on the copper walls …


Future plans

• New magnetic configurationMagnetic coils will be replaced by permanent magnet rings

• A new cylindrical water cooled plasma chamber more suitable for the next magnetic configuration possibility of working in long pulse mode

• Far future change the RF generator frequency (10 GHz) to improve the plasma density

Aim : for high power accelerators, H- current of a few tens of mA at 50 to 100

kV


Proton Driver Activities Proton Driver Activities

@ Saclay@ Saclay

3 MeV NC RFQ3 MeV NC RFQ


@ Saclay@ Saclay

Set up of a 3 MeV – 100 mA Set up of a 3 MeV – 100 mA proton beamproton beam

a.a.ECR Source (SILHI)ECR Source (SILHI)

b.b.3 MeV 352 MHz RFQ3 MeV 352 MHz RFQ

c.c.DiagnoticsDiagnotics

d.d.DumpDump


A scale 1 Aluminium model of the RFQ


provisional assessment of the first (1/6) RFQ Section

•Acceptable Leaking level : 5,65. 10-10 Pa. m3. s-1

•Positive RF Tests•First (1/6) RFQ section validated


RF power

•RF installed, Waveguides connected to the 1.3 MW RF installed, Waveguides connected to the 1.3 MW loadload

•Cooling set up finalized (1MW in Cu)Cooling set up finalized (1MW in Cu)•RF Tests on load to begin soon 04-2005RF Tests on load to begin soon 04-2005..


Diagnostics

Wire scanner and BPM installed in the LEB section and tested with SILHI (H+) Beam (100 keV 100 mA)


Beam dump (300 kW)

Design done : Nickel


Planning RFQ

N° Nom de la tâche

1 IPHI dans l'INB 482 Partie réglementaire9 Aménagements extérieurs aux halls10 Distribution électrique11 Aménagement bureaux labos. et PCP12 Système général de refroidissement et RF13 Refroidissement RFQ14 IPHI 100 keV15 Installation SILHI / LBE16 Essais SILHI 100 keV17 IPHI 3 MeV18 Fabrication prototype RFQ19 Installation du hall RF pour tests sur charge20 Fabrication des tronçons RFQ (y compris brasage et reprise)21 Assemblage système RF, RFQ, LHE, bloc d'arrêt22 Mise en place des protections bilogiques23 Conditionnement HF du RFQ24 Montée en puissance 3MeV pulsé -> CW25 Essais 3 MeV faisceau continu26 Tests chopper au CERN27 Démontage et transport vers le CERN28 Installation IPHI + chopper au CERN29 Conditionnement HF du RFQ30 Essais 3 MeV mode pulsé

01/11 30/06

01/11 31/12

05/02 31/08

01/07 30/01

12/04 10/01

13/01 31/05

01/10 30/11

07/07 31/03

18/05 31/03

28/12 26/05

01/12 10/05

29/05 14/07

17/07 12/01

15/01 10/07

11/07 11/09

15/01 16/11

19/11 21/12

24/12 16/05

T3 T4 T1 T2 T3 T4 T1 T2 T3 T4 T1 T2 T3 T4 T1 T2 T3 T4 T1 T2 T3 T4 T1 T2 T3 T4 T1 T2 T3 T4 T1 T2 T3 T4 T1 T2 T3 T4 T11999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009

June 2007?



@ Saclay

Superconducting Cavities


Proton LINAC : Overall DesignProton LINAC : Overall Design

High Energy


(5-cell 704 MHz)

I njector

(352 MHz)


SC or NCResonators

500

MeV 600 MeV XADS

200

MeV

100

MeV

5M

eV

100

keV


LowBeta=0.47

Medium Beta=0.65

High Beta=0.85

1-2 GeV EURI SOL

High Energy


(5-cell 704 MHz)

I njector

(352 MHz)


SC or NCResonators

500

MeV 600 MeV XADS

200

MeV

100

MeV

5M

eV

100

keV


LowBeta=0.47

Medium Beta=0.65

High Beta=0.85

1-2 GeV EURI SOL

High Energy


(5-cell 704 MHz)

High Energy


(5-cell 704 MHz)

I njector

(352 MHz)


SC or NCResonators

500

MeV 600 MeV XADS

200

MeV

100

MeV

5M

eV

100

keV


LowBeta=0.47

Medium Beta=0.65

High Beta=0.85

1-2 GeV EURI SOL

I njector

(352 MHz)


SC or NCResonators

500

MeV 600 MeV XADS

200

MeV

100

MeV

5M

eV

100

keV


LowBeta=0.47

Medium Beta=0.65

High Beta=0.85

1-2 GeV EURI SOL

SPLEUROTRANS

CW or Pulsed LINAC

Niobium Superconducting

Cavities

Spoke Elliptical

QWR


Quarter Wave Resonator 88 Quarter Wave Resonator 88 MHz MHz = 0.07 = 0.07Design, Manufacturing, Chemistry, Assembly

RF Tests in vertical cryostat at Saclay

Intermediate AccelerationIntermediate Acceleration

SRF Workshop – G. Devanz et al. (July 2005)


High Energy : Low-High Energy : Low-

Design and Manufacturing of Design and Manufacturing of

Low-Low- Elliptical Cavity Elliptical Cavity

( 5-cell 700 MHz ( 5-cell 700 MHz = 0.47 ) = 0.47 )

SRF’2005 Workshop – G. Devanz et al.

Cold Tuning System and Cold Tuning System and High Power CouplerHigh Power Coupler

( 1 MW pulsed mode )( 1 MW pulsed mode )

Cavity expected at Saclay mid-2006Cavity expected at Saclay mid-2006

Mutual interest with CARE/SRFMutual interest with CARE/SRF


Nb Cavity ( CEA Saclay / IPN Orsay )Nb Cavity ( CEA Saclay / IPN Orsay )

5-cell 700 MHz 5-cell 700 MHz = 0.65 = 0.65

LINAC’2004 – B. Visentin et al.

A5.01 Rres = 2.2 nW

1,E-09

1,E-08

1,E-07

1,E-06

0,2 0,3 0,4 0,5 0,6

1 / T ( K-1 )

R( W )

RS = RBCS + Rres

RBCS

Halbritter's Code

1E+08

1E+09

1E+10

1E+11

0 2 4 6 8 10 12 14 16 18 20

Eacc ( MV/m )

Q0

Vertical Cryostat (Fast Cooling)

Horizontal Test in CryHoLab (B1)

quench

Design, Manufacturing, Chemistry, Assembly

RF Tests in vertical and horizontal cryostat ( Cry-Ho-Lab ) at Saclay

High Energy : Medium-High Energy : Medium-


Technological InfrastructuresTechnological Infrastructures

( Chemistry – Clean Room – CryHoLab )( Chemistry – Clean Room – CryHoLab )

at Disposal for European Collaborationsat Disposal for European Collaborations

5-cell

elliptical cavity

3-spoke

Cavity

Jülich


Technological Infrastructure at SaclayTechnological Infrastructure at Saclay

Chemistry

High Pressure Rinsing

Clean Room (class 100)

Vertical CryostatsHorizontal Cryostat

Cry-Ho-Lab

RF Power

Klystron – IOT

1300 – 700 MHz


Triple-Spoke Niobium Cavity ( FZ - Jülich )Triple-Spoke Niobium Cavity ( FZ - Jülich )

784 MHz 784 MHz = 0.2 = 0.2

Saclay contribution :

•Inner Surface Chemistry ( 100 m removed )

•High Pressure Rinsing

•Assembly in Clean Room (class 100)

•Transport to FZ Juelich (under vacuum)

Intermediate AccelerationIntermediate Acceleration


Low-Low- Niobium Cavity ( INFN Milan ) Niobium Cavity ( INFN Milan )

5-cell 700 MHz 5-cell 700 MHz = 0.47 = 0.47

EPAC’2004 – A. Bosotti et al.

Z5.02 cavity - Rres = 7.5 nW

1,E-09

1,E-08

1,E-07

1,E-06

0,2 0,3 0,4 0,5

1 / T ( K-1 )

R ( W )

RBCS

RS = RBCS + Rres

Halbritter's Program

Z5.02 INFN Milan Nb 5-cell Cavity( RF Test @ Saclay in vertical cryostat )

Rres = 7,5 nW Eacc = 17 MV/m Q0 = 4.109

1E+09

1E+10

1E+11

0 2 4 6 8 10 12 14 16 18 20

Eacc ( MV/m )

Q0

Limited by RF pow er

and f ield emision

Chemistry, Assembly and RF Test in vertical cryostat at Saclay

Near future : Test in CryHoLab

High EnergyHigh Energy



@ Saclay

Software


Development and commercialization of codes

During the last decade, Saclay has developed several codes which form now a complete package to design a linac architecture and to simulate the beam behaviour in a linac:

● Design codes

● Transport codes


Dissemination

These codes are used by international labs:• RAL (UK)• CERN • IPNO, LPSC, GANIL, (FRA)• JAERI (JAP)• GSI, IAP, FZJ (D)• INFN (ITA)• MSU, ORNL, LBNL, LANL (USA)• CAT (INDIA)

and companies:• HITACHI (JAP)• AES (USA)


CARE participation

In the High Intensity Pulsed Proton Injector (HIPPI) JRA framework, these SW are used for :

• investigations on the beam neutralization effect

• modelization of an ECR ion source

• participation to the code benchmarking with other european labs (GSI, RAL, IAP Frankfurt)


More ?


0

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110

0 2 4 6 8 10 12 14 16 18 20

t(µs)

%

H+_100mA_95keV_4e- 5hPa_Rect-Rigid_1cm

protons

Fraction of SCC

Source SILHI (H+) and the Low Energy Beam

•Measurement of the Space Charge Conpensation (A.Benismail PhD)

•Emitance measurements


RF coupling for the RFQ

The .Los Alamos scheme (LEDA)Is not optimal

A /4 transition is being tested. Preliminary resulsts are promising


Beam neutralization principle

0

2000

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8000

10000

12000

14000

0 0.02 0.04 0.06 0.08 0.1

r(m )

E(V/m

)

potential well 0

100

200

300

400

500

600

700

800

0 0.02 0.04 0.06 0.08 0.1

r(m)

V(v)

residual gas (H2) in the beam transport line

Electrical neutralization is performed by e- trapping in the potential well of the beam. H2

+ ions are repelled to the pipe

Let's consider a 100 mA proton beam @ 100 keV in a LEBT

electricalfield

Production of e- and H2+ ions by ionization of

residual gas

p + H2 p + e- + H2+


Beam neutralization: background

• People (including us) use to simulate the beam dynamic with full space charge or, sometimes, without space charge assuming a perfect neutralization (each proton is married to an e-).

• But experiments and some theoretical analysis showed that the situation is more complex.

• The beam charge may be partially compensated and the neutralizing distribution is not similar to the beam one.

• This may lead to emittance growth.

• The transcients may be problematic for pulsed machines.

• We aim to study this topic using a PIC code (Cartago) in a first approach, in 2D (XY and RZ). Collisions MUST be included to refine the predictions for the equilibrium.


Beam neutralization: DC proton beam in a drift

0

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0 2 4 6 8 10 12 14 16 18 20

t(µs)

%

H+_100mA_95keV_4e- 5hPa_Rect-Rigid_1cm

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110

0 2 4 6 8 10 12 14 16 18 20

t(µs)

%

H-_100mA_95keV_4e- 5hPa_Rect-Rigid_1cm

Observed by R. Baartman and D. Yuan, "Space-Charge Neutralization Studies of an H- Beam", EPAC88.


ECR source modelization

• Loss predictions of beam dynamics codes are very sensitive to input distributions.

• A better optical quality at the beginning of the injector increases the efficiency and simplifies the strategy for the implementation of collimators.

• We can dream also to increase the performances in term of reliability, rise time, ...

WHY?


ECR source: the basics

Permanent Permanent magnetsmagnets

CoilsCoils

plasmaplasma

RFRF

ExtractionExtraction


Examples of simulations

These first simulations show that the chamber geometry may impact on the source performances.

Ey in plasma chamberEz

Ey

TE10

mode isinjected

Cylindrical boxRectangular box


Code benchmarking

proton driver activities @ saclay

Documents