alpi and piave status and perspectives - nupecc.org and piave status and perspectives. ... ~ 40 mv...

Porcellato HISB wg 4 June04 LNL-INFN 1

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Anna Maria PorcellatoLab. Naz. INFN

Legnaro (PD) Italy

ALPI and PIAVEStatus and

perspectives


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Istituto Nazionale di Fisica NucleareLaboratori Nazionali di Legnaro

ALPI Complex

TandemXTU

High EnergyPhysics Building

CN accelerator


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Contents

Evolution of ALPI - The resonators: Pb/Cu, full Nb, Nb/Cu QWRs

Status of PIAVE, the ALPI Positive Ion Injector- The resonators: full Nb QWRs, RFQs

ALPI performance and upgrading


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Tandem+ALPI and the PIAVE-Injector

SCBooster

ALPI

XTU-Tandem

Positive Ion InjectorPIAVE

ECRIS Alice350kV platform

Reliable

Under Commissioning

Upgraded EX

. Hall 3

EX. Halls 1 and 2


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ALPI Evolution

ALPI: Linear Accelerator for Heavy Ions

Funded in 1988 (97 Pb/Cu cavities, operating at 3 MV/m)

Medium β section completed in ‘94 (44 QWR, Pb/Cu, 160 MHz)

1st high β cryostat installed at the end of 1995 (Nb/Cu, 160 MHz); 2nd and last in 2001

3 low β cryostats on line between 1996 and 1999 (12 QWR, Nb, 80 MHz)

First beam on target in May 1994; Since then ALPI is operating according to the PAC schedule.


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Tandem+ALPI Complex•XTU-tandem: 15 MV routinely available, 30÷8 MeV/u

for H ÷ 127I; 70% beam-time

•ALPI: Linear superconducting QWR accelerator; ~ 40 MV

equivalent voltage for 12C ÷ 127I; 30% b-time

AVA

ILA

BLE

Accelerated beams in ALPI (2)8 p-nA on target with A=100 masses available

700 ps (FWHM) bunch length on the exp. target

12C 6+ @ 240 MeV (20 MeV/u), 82Se17+ @ 630 MeV (7.7 MeV/u)

DA

TA

Completed: Energy Upgrade Programme

In progress: Programme for efficient cooling of the first 3 cryostatsTO B

E N

OTE

D


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XTU-ALPI: Beam on Target

0

1000

2000

3000

4000

5000

6000

700019

89

1990

1991

1992

1993

1994

1995

1996

1997

1998

1999

2000

2001

2002

time (years)

Bea

m o

n T

arget

(hou

rs)

2002: 5500

2003:5500


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Accelerated beams in ALPI (1)

Date Ion Cavities β in β out ∆Ε/q/cavity Output Energy Output Energy [MeV/Ch-u/cav.] [MeV] [MeV/u]

21-Feb-00 32S9,12+ 25 0.107 0.142 0.435 300 9.4

27-Feb-00 36S12+ 29 0.101 0.140 0.449 328 9.1

02-Mar-00 62Ni11+ 14 0.088 0.105 0.428 316 5.1

14-Mar-00 48Ca9+ 18 0.079 0.097 0.436 206 4.3

14-Nov-00 32S9,12+ 31 0.107 0.153 0.477 350 10.9

22-Nov-00 58Ni6,15+ 29 0.084 0.111 0.367 330 5.7

30-Nov-00 80Se11,17+ 31 0.079 0.112 0.453 470 5.9

04-Feb-01 58Ni13+ 13 0.087 0.100 0.395 267 4.6

14-Feb-01 58Ni13+ 29 0.087 0.118 0.456 380 6.5

22-Feb-01 83Se11,17+ 41 0.079 0.124 0.502 590 7.2

03-Mar-01 83Se11,17+ 43 0.079 0.129 0.537 631 7.7

15-Jun-01 36S9+ 22 0.093 0.117 0.429 230 6.4

29-Jun-01 74Se11,18+ 22 0.085 0.111 0.439 422 5.7

07-Jul-01 82Se6,16 32 0.074 0.110 0.487 464 5.6

12-Jul-01 65Cu6,15 12 0.080 0.093 0.374 260 4.0

13-Nov-01 56Fe6+ 32 0.083 0.120 0.562 380 6.8

05-Nov-01 12C6+ 43 0.137 0.207 0.523 240 20.0


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Accelerated beams in ALPI (2)Date Ion Cavities β in β out ∆Ε/q/cavity Output Energy

[MeV/Ch-u/cav.] [MeV]

20-Feb-02 12C6+ 43 0.134 0.207 0.541 240 26-Feb-02 16O7+ 44 0.124 0.197 0.567 289 2-May-02 48Ca9+ 29 0.08 0.112 0.525 280 14-Mar-02 48Ca9+ 18 0.079 0.097 0.616 206 24-May-02 64Ni11,16+ 29 0.088 0.113 0.585 500 1-Jun-02 16O7,8+ 30 0.13 0.183 0.520 250

30-Jun-02 32S9,12+ 46 0.099 0.176 0.572 463 31-Oct-02 32S9,12+ 41 0.108 0.176 0.587 463 8-Nov-02 80Se11,18+ 33 0.081 0.127 0.598 600 16-Nov-02 12C6+ 43 0.134 0.207 0.539 240 27-Nov-02 40Ca10+ 15 0.092 0.116 0.605 250 1-Dec-02 40Ca10+ 15 0.092 0.116 0.605 250 5-Dec-02 16O7+ 35 0.124 0.183 0.553 250 10-Dec-02 104Ru12,20+ 29 0.075 0.111 0.566 600 14-Dec-02 32S9+ 15 0.098 0.124 0.643 230 20-Dec-02 12C6+ 43 0.134 0.207 0.542 240 8-Jun-03 64Ni+12 14 0.08 0.100 0.663 300 4-Jul-03 48Ca9+ 19 0.08 0.106 0.625 252

3-Nov-03 16O6+ 17 0.08 0.149 0.631 166 10-Nov-03 80Se11,18+ 35 0.077 0.149 0.634 630


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Accelerated beams in ALPI (3)

Date Ion Cavities β in β out ∆Ε/q/cavity Output Energy [MeV/Ch-u/cav.] [MeV]

19-Feb-04 54Cr+10 22 0.080 0.108 0.615 295 5-Mar-04 40Ca+10,14 47 0.104 0.184 0.651 631 13-Mar-04 54Cr+11 20 0.080 0.108 0.615 295 16-Mar-04 58Ni+11 31 0.077 0.114 0.563 350 25-Mar-04 36S+9 12 0.094 0.116 0.704 225 1-Apr-04 64Ni+11 35 0.075 0.116 0.602 400 13-Apr-04 82Se+12 46 0.068 0.115 0.597 505 23-Apr-04 90Zr+13 46 0.067 0.115 0.612 555


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PIAVE

EXPERIMENTALHALLS 1, 2

EX.

HALL

3

CR10 CR9 CR8 CR7 CR6 CR5 CR4 CR3 B2

CR12 CR13 CR14 CR15CR16 CR17 CR18 CR19 CR20 B4

COLD BOX

TANDEM

β=0.056, 80 MHz, full Nb.

β=0.13 160 MHz Nb/Cu.

β=0.11, 160 MHz,Nb/Cu (Pb/Cu)

B3

ALPI-layout


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2004 ALPI currents on target

Ion [pnA] on targetLinac transmissionI target/I source

36S9+ 6.56 24.08 0.3758Ni11+ 0.50 27.50 0.4282Se12+ 6.67 26.23 0.3290Zn13+ 3.08 30.08 0.2764Ni11+ 5.45 29.56 0.40


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ALPI medium βPb/Cu resonators

50 installed resonators from 1992 to 1994Pb/Cu, 160 MHzAverage Ea @7W =2,68 MV/mFour cavities still installed in the bunching cryostats


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ALPI Mar 1995

0

3

6

9

CR4lowbeta

CR5lowbeta

CR6lowbeta

CR7 CR8 CR9 CR10 CR12 CR13 CR14 CR15 CR16 CR17 CR18 CR19 CR20(highbeta)

Cryostat

Ea [MV/m]

Pb/Cu Nb Nb/Cu

Performance of ALPI accelerating cavities in 1995; four other cavities are installed in the bunching cryostats


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QWR Nb sputtering at Legnaro

1988: a research project on QWR Nb sputtering at LNL starts (Palmieri)

1991: first sputtered prototype;

1993: three prototypes reach 6 MV/m @ 7 W dissipated power

1995: Four high β resonators installed in ALPI (4 MV/m @ 7W); process

improvements allows to reach 7 MV/m @ 7W

1998: Four new cavities, still on line, operate at 6 MV/m @ 7W

1998: The substitution of Pb with Nb allows to reach 4 MV/m in a medium β

ALPI resonator

2003 Upgrading of ALPI medium β resonators completed.


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ALPI status in 1999

• Medium and high β sections operational;• Low β section installed but not usable;• Improvement in medium β cavity performance

obtained by replacement of Pb film with Nb;• Leaks in the cryogenic and beam line valves.

Why not associatecryostat maintenance with cavity upgrading?

ALPI medium β upgrading possibility at: - Low cost, without necessity of devoted resources- No interference with ALPI operationBetter ALPI reliabilityUse of sputtering technology developed at LNL


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Cryostat maintenance

•Change of the leaking cryogenic valve (external actuator)

•Change of the leaking Vitonsealing in the cryostat beam line valves, from resonator integral conditioning (changed + shielded through stainless steel rings)

•Gaskets in the He circuits(changed + fixed by silver plated screws)

•RF lines (Mechanical adjustments + Cu re-plating)

•Beam damage around beam ports: in the mylar wrapping of the thermal shield (shielding of aluminated Mylar by tantalum protection)

• Upgrading of the resonators


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a at

7 W

[MV

/m]

0

1

2

3

4

5

6

7

8

CR7 CR8 CR9 CR10 CR12 CR13 CR14 CR15 CR16 CR17 CR18 CR19(highBeta)

CR20(highBeta)cryostat

Installed Nb/Cu resonators

To be repaired

Removed Pb/Cu resonatorsApr 99 Jan 01 Jan 01 Dec 00 Oct 00 Mar 02 Oct 01 Mar 01

Feb 98

May 02 Jul 03 Jan 03 Sep03

The increase in performance by Nb/Cu sputtering

The accelerating fields reached by Nb/Cu resonators at 7 W (blue bars) are compared with the ones obtained by the same resonators when still Pb plated (black bars). Two cavities are not in operation. Black arrows indicate a decrease in performance (June 2003) with respect to previous results

Out

of f

requ

ency

Rf l

ine

dam

aged


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Pb NbResults (operational)

Ea (@7 W): from 2.4 (Pb) to 4.4 MV/m (Nb)

Despite some limitations in the copper base

(not best Cu quality, sharp edges & Sharp holes

in high-I regions, hidden volumes in brazed joints)

• No interference with ALPI operation

• Same cryostat, control system, rf hardware and software

4.4 MV/m

790 keV/u(@ β=βop;Φ=0)


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Nb/Cu resonator advantages

Relatively high accelerating fields

High mechanical stability

Frequency not affected by changes in the He bath pressure (<O.01 Hz/mbar!)

Locked up to 7 MV/m without necessity of fast or “soft” tuners

Very reliable

Easy to put into operation

No degradation with time after installation


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High β section: ALPI sputtered

Nb/Cu resonatorsbe

am p

ort

coup

ler

pick

-up

ALPI β=0.13, 160 MHz resonator views; The cavity has no brazed joint; beam ports are jointed to resonator by indium gaskets

1.00E+07

1.00E+08

1.00E+09

1.00E+10

0 1 2 3 4 5 6 7 8 9 10 11 12

CR20-1CR20-2CR20-3CR20-4

Q

1W 3W

7W

Ea [MV/m]


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Low β section

0

2

4

6

8

10

CR04-1

CR04-3

CR05-1

CR05-3

CR06-1

CR06-3

Cavity

Ea

[MV

/m]

Bulk Nb resonator perforamance

Nb, double wall, 80 MHzExcellent performance, no degradation along yearsInstalled in between 1995-2000Their cooling down was difficult, upgrading of

cryogenic line necessary and scheduled (spring 2004)

Sensitivity to He bath pressure drift: 1Hz/mbar

Eaav May 2003: 6.75 MV/m


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ECR


EX.

HALL

3



COLD BOX

TANDEM

β=0.056, 80 MHz, full Nb

β=0.13 160 MHz Nb/Cu

β=0.11, 160 MHz,Nb/Cu

B3

β=0.110, 160 MHz,Pb/Cu


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He transfer to the lower β branch

1. More total ∆P forcooling (30→70 mbar), refrigerator and cryostats valves changed (done in 07/03)

2. More He Flux2→4 compressors(160 to 205 g/s) (received 09/03)

3. Equalization of hydraulic routes to various cryostats (scheduled in 04-05/04): ∆P ~ K on each cryostat

MainColdBox

4.5 K

7 K

Liquid

Gas

3. Equalization of hydraulic routes to cryostats(similarly for thermal shield gaseous He)


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Some work on the mechanical tuners needed

1997-2000: Installation of the 3 lower-β cryostats1998: the CR06 cavities, locked on line at up to an energy of ~ 6 MV/m (58Ni shift)- fast f0 changes: no problem- slow f0 changes: (He ∆P < 10 mbar/min kept for days) compensated by the slow tuner in f0 feedback mode

(poor reproducibility of tuner mechanics noted). The low-β cavity commissioning was interrupted (cryogenics problems)

May 2003: the linac operation team can test all 12 cavities at the same time: a) cavity performancen is very good; b) fast f0 changes OK; c) mechanical tuners could not compensate for ∆P variations of 10÷100 mbar/min(mechanical faults)November 2003 – January 2004: systematic tests on all the resonators (chaired by the resonator designer), to fix the slow tuning problemsApril 2004: Systematic test on PIAVE QWR with the old tuner: the He pressure fluctuations are lower than in ALPI. The cavities can be locked adjusting continuously the frequency by the old tuners while the He pressure changes up to 50 mbar/minuteMay 2004: Four cavity equipped with new design tuners, backlash free, are installed in ALPI.


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1. Fast f0 changes (acoustic vibrations, 40÷200 Hz): the dampers keep the frequency oscillations within a few Hz (no need of fast tuners) - checked in March 2002

3. Slow f changes (He-P variations0seconds÷minutes): a slow tunerfollowing the pressure fluctuations is required, the present one worked in PIAVE, where ∆f are lower, but is not enough reliable in ALPI; a new type, based on leverage, is under test in ALPI

2. ALPI cryogenic plant has drifts in He bath pressure: - it was designed for Pb/Curesonators whose sensitivity to change in bath pressure is < 0.01 Hz/mbar- it has to feed both LHe circuit and the thermal shield circuit operating at 7 bar, thus making regulation difficult

Frequency locking:keep the QWRs

at 80 MHz ± 2÷3 Hz

28/05 00.23 dalle 00.23.18 alle 01.25.45

0.130.14

0.150.16

0.170.180.19

0.20.21

0.220.23

0 600 1200 1800 2400 3000 3600secondi

B2CR4CR5CR6CR7CR8

Some mechanical improvement needed

Pressure drifts in ALPI cryostatsbar

sec


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ALPI output energy –Tandem injector

0

5

10

15

20

25

30

0 20 40 60 80 100 120 140

AALP

I out

put [

MeV

/u]

ALPI Dec 1998

ALPI 2003 (low beta not included)

ALPI 2003 (low beta included)

12C6+ 28Si11+ 40Ca14+ 63Cu17+

16O7+ 32S12+ 58Ni17+ 79Br18+ 90Zr19+ 127I 21+

Tandem 15 MV; F,F1998 : 11 Pb/Cu cryostats2003: 13 Nb/Cu cryostats

ALPI output Energy Gain: 45% for 6C;69% for 127ILinac Energy Gain: 91% for 6C;132% for 127I

(low β not included)


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ALPI output energy once added 6 more Cryostats

0.200.300.400.500.600.700.800.901.001.10

1 6 11 16 21 26 31 36 41 46 51 56 61 66 71 76 81 86 91 96

Cavity #

TTFn

05101520253035404550

1

ALPI

out

put e

nerg

y [M

eVu]

TTFnALPI output energy [MeV/u]

12C6+

0.200.300.400.500.600.700.800.901.001.10

1 6 11 16 21 26 31 36 41 46 51 56 61 66 71 76 81 86 91 96

Cavity #

TTFn

0

2

4

6

8

10

12

14

161

ALP

I out

put e

nerg

y [M

eVu]

TTFnALPI output energy [MeV/u]

90Zr13,17+Tandem at 15 MV

Tandem at 15 MV


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PIAVE Status


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Why to switch from a Tandem to a q+injector?

ALPI Output with the two Injectors

0

10

20

30

0 50 100 150 200 250A

E/A

[MeV

/u]

Tandem+ALPI (G-F) (1-10 pnA)

PIAVE+ALPI (40-200 pnA)

New Injector

Tandem

• MORECURRENT

• HEAVIERMASSES

• MORE BEAM TIMEAVAILABLE (TWO INJECTORS)


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PIAVE design values for RFQsReference beam: 238U28+ (pre-bunched) from an ECR on a 315 kV platform

SRFQ1 SRF2In Out In out

Energy 37.1 351.3 585.4 KeV/u8.82 83.61 139.33 MeV

Beta 0.0089 0.0275 0.0355Voltage 148.0 148.0 280.0 280.0 kVLength 138.9 74.4 cmN of cells 43 13m 1.2 2.8 2.7 2.8a 0.7 0.4 0.8 0.8 cmR0 0.80 0.80 1.53 1.53 cmφs 40.0 18.0 12.0 12.0 degEp,s 24. 25.5 MV/mU 1.8 3.5 J

Acceptance (norm) 0.8 mm mrad

Output long. emittance 0.7 ns keV/u


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PIAVE Injector Layout

Two SRFQs

ECR + LEBT EightQWRs

to ALPI


Iq/M 28/238Energy Range 38÷948 keV/mβ range 0.0094÷0.045Current 1 eµAT. Emittance 0.5 mmmrad (norm)L. Emittance < 0.7 nskeV/u

ECRIS

to SCbooster

SRFQsQWRs

PIAVE the new injector

In Feb 2003 a small fire due to a short circuit forced to stop ECR commissioning

New start-up of the ECR Ion Source in March 2004 in the previous conditions

Element q I (eµA)16O 6+ 10

40Ar 12+ 1

84Kr 14+ 0.4

129Xe 18+ 0.5

63Cu 11+ 0.5÷0.7107Ag 17+ 0.7 ÷0.8

Typical Beams


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Beam Commissioning from ECRIS to SRFQs

∆t < 500 ps, notransverse steering inducedTransmission: 89%

Buncher

Matching: obtained (as computed) at the SRFQ1 entrance


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beamline

SRFQ2

1.38 m 0.74 m

SRFQ1Two superconducting RFQs in a cryostat

585 keV/u (β = 0.035)37 keV/u (β = 0.0089)


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SRFQ2 structure

Nb tank, full Nb, RRR 250, 3 mm thick

Trapezoidal-shaped stems, the vertical ones displaced with respect to horizontal ones

Modulated electrodes, rod-type, carved inside

Empty, baking cylinders

•Ti Stiffening ribs •Ti /Nb end flange

0.8m

0.74m


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PerformanceQ0 vs Ep: both above specsBoth installed in the line cryostatLeak check of cryogenic circuit OK

Locking conditions Tested both in the test cryostat and

on the beam line for relativily short times (hours): Slow f0 changes and their controlFast f0 changes and their control

SRFQ1 SRFQ2

Frequency 80 80 MHz

Length 1.41 0.8 m

Diameter 0.81 0.81 m

Weight 280 170 Kg

∆V_interelectrode 148 280 kVModulated cells 41 13Es,p 25.5 25.5 MV/mEs,p/Ea 12 12Bs,p 0.025 0.03 TStored Energy 2.1 3.6 JPdiss (set) 10 10 WQ 1x108 2x108

Milestones on SRFQs


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1.E +07

1.E +08

1.E +09

0 5 10 15 20 25 30 35

P eak S urface F ie ld [M V /m ]

Q

S R FQ2S R FQ1

10 W

10 W

SCRFQ2SCRFQ1

SRFQ1 - SRFQ2: performance achieved


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Frequency shift induced by He bath pressurization

∆F = 39 Hz/mbar for RFQ2∆F = 48 Hz/mbar for RFQ1

kHz y = -0.039x + 0.0971

-12

-8

-4

0

0 50 100 150 200 250 300∆ P [mbar]

frequency shift [kHz]


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How do we cope with slow drifts?

IMPO

RTA

NT

FOR

HE

IN R

EFR

IGER

ATI

ON

CYC

LE

Tuners performanceFrequency range: 150 ÷ 300 kHz

(huge)Sensitivity: 0.5 Hz (good)

Speed: ~ 2÷3 Hz/s

Cryogenic-Plant Specs

∆P=1.2 ±0.05 bar; ∆P/∆t < 2 mbar/min → 1.33 Hz/s

By deforming both tuning plates in frequency feedback mode

One for +∆f, the other for –∆f(no mechanical backlash)

In the test cryostat: Margin: factor 2∆f < 1 kHz/day, at < 1÷2 Hz/s

NO PROBLEM!


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Conditioning: faster than in the test cryostat. The couplers located on the cavity bottom probably helped rf antennas: OK both for Q and movementCavity Q similar to the ones measured in laboratory for both RFQs (if the dissipative load coming from the fast tuners is taken into account)SRFQ2: locking condition (20 Hz bandwidth) maintained for up to 60 minutes, lost for He pressure changes out specification or sometimes for not optimal tuning operationFast tuners: increase the locking window from from 20 Hz to 200 Hz (SRFQ2) and 70 Hz (SRFQ1, to be increased). Microphonics at negligible level: unlocking at 80 MHz (master) due only to He pressure drifts. Slow tuners will work together with the fast tuners in the next test.

On line testApril 2004


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SRFQ2 locking to the master oscillator (80 MHz)

0123456789

10

0 60 120 180 240 300 360Time [min]

68 % Eacc,n

84 % Eacc,n

∆P

*10

[mba

r], T

i [K

], H

e le

vel*1

0 [%

]

3.6mb/min

21.4mb/min

(84 % Eacc,n ⇒ A/q =7.2 ⇒ 208Pb29+ e.g.)

Tuner 2 not properly working


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1.00E+07

1.00E+08

1.00E+09

1.00E+10

0 1 2 3 4 5 6 7 8 9 10 11 12

Ea (MV/m)

Q

Q at 7W

old specifications

new specifications

PIAVE bulk Nb QWR's

PIAVE 80 MHz, β=0.047 QWR

Low-β QWR’s for PIAVE

80 MHz, low- β QWR cryostat

Mechanicaldamper

High gradientNo fast tuner

requiredBuilt and testedInstalled and

operational


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4. CRYOGENIC SYSTEM UPGRADE

3. LOW BETA CAVITIES UPGRADE

2. PIAVE

1. ECRIS OPERATION

ALPI low-β section: • Cavities locking to the linac clock to be improved

•To be cooled efficiently

4

12

3


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On line tests of PIAVE low-β QWR’s

Good performance for CrQ1-PIAVE resonators:locked up to 5 MV/m making use of the old type slow tuner controlled by an improved version of the “soft” tuner program

Q values lower than the ones measured in laboratory for CrQ1-PIAVE resonators; two cavities of the cryostat out of frequency; microphonic noise more relevant than in CrQ1-PIAVE resonators.

Not negligible power consumption at 4 K due to the rfdissipation in the RF input line in strong overcouplingcondition used to make locking possible.Cryostat removal from the beam line to fix the problems foreseen soon.

The resonators should recover the performance by HPWR


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Coming next

PIAVE beam test foreseen in October 2004Final test of all the automatic procedures on the

refrigerator, operating with the whole cryogenic load, scheduled in September 2004

Beam injection of a PIAVE beam in ALPI foreseen by the end of the year

Improvement of ALPI cryogenic system to allow operation of low β resonators completed by July 2004

Substitution of old tuners with new designed ones in low β resonators in progress.


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Present ALPI output energy –Tandem injector

Tandem 15 MV; F,F1998 : 11 Pb/Cu cryostats2003: 13 Nb/Cu cryostats

ALPI

0

5

10

15

20

25

30

0 20 40 60 80 100 120 140

AALP

I out

put [

MeV

/u]

ALPI Dec 1998

ALPI 2003 (low beta not included)

ALPI 2003 (low beta included)

12C6+ 28Si11+ 40Ca14+ 63Cu17+

16O7+ 32S12+ 58Ni17+ 79Br18+ 90Zr19+ 127I 21+


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ALPI injected by PIAVE

Performance of different ECR sources compared with LNL negative source beam intensityPIAVE-ALPI output energy when fed by typical ECR beamsPresent ALPI authorization limitConstraintsALPI CompletionPerformance of ALPI after completionReachable ALPI Energy stripping the ALPI beam


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ECRIS currents, compared to LNL negative sourceIon A state of charge [LNL ALICE I [Atomki]1 I [S.nanogan] 2 IKF SERSE I [Argonne ECRIS] I after Tandem Stripping

e micro A e micro A e micro A e micro A e micro A e micro A e micro AC 12 5 8.6 25 1.983N 14 5 29 0.717N 14 6 1.5 1.457O 16 5 203O 16 6 10 81 200 150 540 1.510O 16 7 4 52 0.548F 19 3 24F 19 7 1.294

Ca 40 10 0.935Ca 40 12 0.079Ar 40 8 202 200 110Ar 40 9 100 80Ar 40 12 1 200Ar 40 14 0.034 1 2 84Fe 56 11 2.8 0.784Fe 56 13 1.4 0.075Fe 56 15 0.22 0.016Ni 58 10 8.7 0.416Ni 58 11 0.775Ni 58 14 0.2 0.024Ni 58 16 15Ni 58 17 6163 Cu 11 163 Cu 14 0.3Ge 74 16

http://www.lnl.infn.ithttp://www.phys.jyu.fi/ecris02

http://www.lns.infn.ithttp:hsbpc1.physik.uni-frankfurt.de

http://www.pantechnik.comhttp://www.atomki.hu

M. Cavenago, private communication

No isotope separation

http://www.phys.jyu.fi/ecris02

http://www.lns.infn.it/

http://www.atomki.hu/


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ECRIS currents, contIon A state of charge [LNL ALICE I [Atomki]1 I [S.nanogan] 2 IKF SERSE I [Argonne ECRIS]

e micro A e micro A e micro A e micro A e micro A e micro AKr 84 11 1 10.3Kr 84 12 1 8.7 27Kr 84 14Kr 84 15 0.5 10Kr 84 22 0.1Kr 86 18 137 38.5Zr 90 17Ag 107 17 0.8Sn 120 16 0.675Sn 120 19 0.24Xe 132 15 0.9Xe 132 17 0.6 30Xe 132 18 0.5Xe 132 25 10Xe 132 27 3 78Xe 132 30 38.5Ta 181 24 3Pb 208 25 15Au 197 26 10 2.5Au 197 29 2U 238 28U 238 31 2U 238 37 6

http://www.phys.jyu.fi/ecris02http://www.lns.infn.it

http:hsbpc1.physik.uni-frankfurt.dehttp://www.pantechnik.com

http://www.atomki.huM. Cavenago, private communication

No isotope separation

http://www.phys.jyu.fi/ecris02

http://www.lns.infn.it/

http://www.atomki.hu/


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Energy outputPIAVE injection, 2004 ALPI

0.0

5.0

10.0

15.0

20.0

25.0

30.0

0 50 100 150 200 250A

MeV/u

High currentHigh energy

12C5+ 16O6+

14N5+ 40Ar8+ 58Ni11+ 84Kr12+ 120Sn16+ 132Xe17+ 181Ta 24+ 197Au26+ 208Pb25+ 238U28+

12C5+ 16O7+


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PIAVE: - 2 SRFQs at the design accelerating fields- 8 low β resonators at 5 MV/m

ALPI - 12 low β resonators operating at 4.4 MV/m- 44 medium β resonators operating at 4.4 MV/m- 8 high β resonators operating at 5.5 MV/m


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Present authorization limits

For ions from Si to Pb: E < 20 MeV/u I < -30 pnA on target

For ions from C to AlE< -26 MeV/u I<2 pnA on target


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ConstraintsALPI optics was designed for B*ρ=3.3 Tesla*m

An accurate beam transport analysis in ALPI is requiredThe RFQs were designed for 5µA; the spatial charge effect must be

evaluated for larger current (negligible at 5µA)Maximum possible A/Q for the PIAVE RFQs is 8.5RFQ transmission is 45%. At high current the beam losses can produce a not negligible thermal load (0.2W for 1 µA of 238 U).


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ALPI completion

The original ALPI layout foresaw further 6 high β cryostats. The cryogenic lines, magnets, diagnostic box are installed. Only thecryostats and their equipment (cavities, vacuum, rf controller and amplifier…) are missing.The insertion of a low β cryostat is also possible in the low energy

branch (useful in case of very heavy ions). A cryostat is in this case available.It is necessary to verify that the cryogenic system can provide the design power (1.3 kW @ K and 3.5 kW @ 70 K)It is necessary to study in detail the beam optics for the different beams


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Upgraded ALPI Energy outputPIAVE injection

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40

0 50 100 150 200 250A

MeV/u

High current

High energy

High energy (Bro>3.5)

12C5+ 16O6+


12C5+ 16O7+


Upgraded ALPI: ALPI 2004+ 24 high β resonator operating at 5.5MV/m


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Increasing the energy by beam strippingThe final section of ALPI magnetic lattice can not transport theheavier beams at maximum reachable energy. To decrease the beam rigidity and increase the reachable beam energy it is possible to strip the beam in ALPI.Two options are possible: stripping in the diagnostic box beforeALPI U band or stripping in the box after itIn the first case you can select better the beam accelerated in the second linac branch, making radioprotection issues less demandingIn the latter case it is possible to have instead multicharge acceleration in the second linac branch, increasing in such way ALPI output currentThe output energy is similar in the two cases so only the first option is analyzed


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PIAVE


EX.

HALL

3



COLD BOX

TANDEM

β=0.056, 80 MHz, full Nb.

β=0.13 160 MHz Nb/Cu.

β=0.11, 160 MHz,Nb/Cu (Pb/Cu)

B3

ALPI-layout

Stripperposition


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ALPI output energyBeam stripped before the U band

0.0

5.0

10.0

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0 50 100 150 200 250A

MeV/u

ALPI 2004Upgraded ALPI

40Ca10,16+ 58Ni14,24+ 84Kr18,29+ 120Sn16,31+ 181Ta 24,49+ 208Pb25,53+

40Ar8,16+ 56Fe13,22+ 74Ge13,28+ 90Zr17,32+ 132Xe17,39+ 197Au29,52+ 238U28,57+

Upgraded ALPI: ALPI 2004+ 24 high β resonator operating at 5.5MV/m

alpi and piave status and perspectives - nupecc.org and piave status and perspectives. ... ~ 40 mv...

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