status of the fair pbar source k. knie may 3, 2011

Status of the FAIR pbar Source

K. KnieMay 3, 2011

FAIR acceleratorsFAIR accelerators

p-bar target

p-linac

Super- FRS

SIS100 SIS300

HESR

CR

RESR

Unilac

SIS 100

NESR

HESR

Antiproton Production Target

SIS18 Upgrade

CR

FAIR Baseline Layout

RESR

p-linac SIS 300

Accelerator

SuperFRSPANDA

Atomic Phys.

Plasma Phys.Low Energy Exp.

High Energy Exp.

NESR Exp.

FLAIR

Atomic Physics

HADES & CBM

Experiment

FAIR / CERN / FNAL pbar SourcesFAIR / CERN / FNAL pbar Sources

cycle time 10 s (cooling time in the CR)overall pbar yield: 5 × 10-6 pbar/p (scaled CERN data) → 1 × 107 pbar/s

Increases the pbar yield by 50 %

FAIR Collector ring will be operated at h = 1, CERN ring was operated at h = 6

Time needed for stochastic cooling in CR (AC), upgrade possible

FAIR CERN (AC+AA) FNAL

E(p), E(pbar) 29 GeV, 3 GeV 25 GeV, 2.7 GeV 120 GeV, 8 GeV

acceptance 240 mm mrad 200 mm mrad 30 mm mrad

protons / pulse 2 × 1013 1 - 2 × 1013 ≥ 5 × 1012

pulse length single bunch (50 ns) 5 bunches in 400 ns single bunch 1.6 µs

cycle time 10 s 4.8 s 1.5 s

pbar Distribution After the Targetpbar Distribution After the Target

R.P. Duperray et al., Phys. Rev. D 68, 094017 (2003)

ppbar = 3.82 GeV/c ± 3%

From ~ 2.5 × 10-4 pbar / (p cm target) ~ 5 × 10-6 (or 2 %) are "collectable"

z / cm

y / c

m Ep = 29 GeV

MARS Simulation of the pbar MARS Simulation of the pbar Distribution After the TargetDistribution After the Target

-150

-100

-50

0

50

100

150

-50 -40 -30 -20 -10 0 10 20 30 40 50

x [mm]

x' [

mra

d]

after target

acceptance of separator

p = 3.82 GeV/c Dp/p = ± 3%

CERN ACOL Horn, I = 400 kA

Collecting pbars: Magnetic HornCollecting pbars: Magnetic Horn

target beam axis magnetic field area

Collecting pbars: Magnetic HornCollecting pbars: Magnetic Horn

MARS Simulation of the pbar YieldsMARS Simulation of the pbar Yields

-150

-100

-50

0

50

100

150

-50 -40 -30 -20 -10 0 10 20 30 40 50

x [mm]

x' [

mra

d]

after targetafter hornacceptance of separator

p = 3.82 GeV/c Dp/p = ± 3%

yield =pbars in the ellipse

primary protons

MARS Simulation of the pbar YieldsMARS Simulation of the pbar Yields

0.0E+00

2.0E-06

4.0E-06

6.0E-06

8.0E-06

1.0E-05

1.2E-05

1.4E-05

1.6E-05

1.8E-05

2.0E-05

2.2E-05

2.4E-05

2.6E-05

2.8E-05

3.0E-05

3.2E-05

3.4E-05

3.6E-05

3.8E-05

4.0E-05

4.2E-05

4 6 8 10 12 14 16 18 20

target length [cm]

yie

ld [

pb

ar/

p]

after Ir target, dp/p<3%, theta<80mrad

Ir, massive, rms=0.1mm

Ir, massive, rms=1

Ir, massive, rms=1.5

Ir: p = 1.8 b pbar=2.0 b

p

pbar

C: pbar=0.42 b

0.0E+00

2.0E-06

4.0E-06

6.0E-06

8.0E-06

1.0E-05

1.2E-05

1.4E-05

1.6E-05

1.8E-05

2.0E-05

2.2E-05

2.4E-05

2.6E-05

2.8E-05

3.0E-05

3.2E-05

3.4E-05

3.6E-05

3.8E-05

4.0E-05

4.2E-05

4 6 8 10 12 14 16 18 20

target length [cm]

yie

ld [

pb

ar/

p]

after Ir target, dp/p<3%, theta<80mrad

Ir, d=3mm, rms=0.1mm

Ir, d=4.5mm, rms=1mm

Ir, d=6mm, rms=1.5mm0.0E+00

2.0E-06

4.0E-06

6.0E-06

8.0E-06

1.0E-05

1.2E-05

1.4E-05

1.6E-05

1.8E-05

2.0E-05

2.2E-05

2.4E-05

2.6E-05

2.8E-05

3.0E-05

3.2E-05

3.4E-05

3.6E-05

3.8E-05

4.0E-05

4.2E-05

4 6 8 10 12 14 16 18 20

target length [cm]

yie

ld [

pb

ar/

p]

after Cu target, dp/p<3%, theta<80mrad

Cu d=3mm rms=0.1mm

Cu d=4.5mm rms=1mm

Cu d=6mm rms=1.5mm

Temperature Increase in the TargetTemperature Increase in the Target

100

1000

10000

0 0.5 1 1.5 2 2.5

beam width () [mm]

Max

imu

m T

emp

erat

ure

incr

ease

D

T [

K]

DT = 360 K × w-1.68

DT = 310 K × w-1.68

DT = 2100 K × w-1.35

IrCuNi

melting of Ir

melting of Ni

melting of Cu

Fluka simulation

2×1013 protons per pulseGaussian beam profile

29 GeV/c, r = 1 mm ()

0.00

0.02

0.04

0.06

0.08

0.10

0 1 2 3 4 5 6

z [cm]

(dE

/dm

) max

[Ge

V/(

pri

m g

)]

Ir Cu/Ni

cIr = 130 J kg-1 K-1

cCu = 385 J kg-1 K-1

cNi = 440 J kg-1 K-10.0E+00

2.0E-06

4.0E-06

6.0E-06

8.0E-06

1.0E-05

1.2E-05

1.4E-05

1.6E-05

1.8E-05

2.0E-05

2.2E-05

4 6 8 10 12 14 16 18 20

target length [cm]

yiel

d [

pb

ar/p

]Ni/Cu, d=3, rms=0.62

Ir, d=4.5, rms=1

FAIR / CERN / FNAL pbar SourcesFAIR / CERN / FNAL pbar Sources

cycle time 10 s (cooling time in the CR)overall pbar yield: 5 × 10-6 pbar/p (based on CERN data) → 1 × 107 pbar/s

Increases the pbar yield by 50 %

FAIR Collector ring will be operated at h = 1, CERN ring was operated at h = 6

Time needed for stochastic cooling in CR (AC), upgrade possible

FAIR CERN (AC+AA) FNAL

E(p), E(pbar) 29 GeV, 3 GeV 25 GeV, 2.7 GeV 120 GeV, 8 GeV

acceptance 240 mm mrad 200 mm mrad 30 mm mrad

protons / pulse ≥ 2 × 1013 1 - 2 × 1013 ≥ 5 × 1012

pulse length single bunch (50 ns) 5 bunches in 400 ns single bunch 1.6 µs

cycle time 10 s 4.8 s 1.5 s

cycle time 10 s (cooling time in the CR)overall pbar yield: 1 × 10-5 pbar/p → 2 × 107 pbar/s scaled CERN data: 1 × 107 pbar/s

Pulsed Target: FLUKA SimulationPulsed Target: FLUKA Simulation

horn

FLUKA results FLUKA results

pbar, 0 A

pbar, 500 kA

p, 0 A

p, 500 kA

Cu target, r = 6.5 mmprimary protons homogeneously distributed in a disc with r = 1 mm

FLUKA resultsFLUKA results

It is likely that FLUKA overestimates the production cross section. Therefore, the absolute yields might be a factor 2 to high.

0E+00

1E-05

2E-05

3E-05

4E-05

5E-05

6E-05

0 5 10 15 20 25 30

target length [cm]

pb

ar/p

Cu, r_t=6.5mm, r_beam=1mm, 0A

Cu, r_t=6.5mm, r_beam=1mm, 500kA

Cu, r_t=1.5mm, r_beam=1mm, 0A



Cu, r_t=1.5mm, r_beam=0.01mm, 150kA

Li Lens – A Possible Upgrade?Li Lens – A Possible Upgrade?

< 100 mrad can be collected

I = 1 MA (I ~ r²)

Distance target center - lens: 100 mm

technically challenging / expensive

20 mrad < < 80 mrad can be collected

I = 0.4 MA

Distance target center - lens: 220 mm

more simple and reliable, less expensive



0.0E+00

2.0E-06

4.0E-06

6.0E-06

8.0E-06

1.0E-05

1.2E-05

1.4E-05

1.6E-05

1.8E-05

2.0E-05

2.2E-05

2.4E-05

2.6E-05

2.8E-05

3.0E-05

4 6 8 10 12 14 16 18 20

target length [cm]

yie

ld [

pb

ar/

p]


Li Lens, d = 36 mm, I = 1.0 MA

0.0E+00

2.0E-06

4.0E-06

6.0E-06

8.0E-06

1.0E-05

1.2E-05

1.4E-05

1.6E-05

1.8E-05

2.0E-05

2.2E-05

2.4E-05

2.6E-05

2.8E-05

3.0E-05

4 6 8 10 12 14 16 18 20

target length [cm]

yie

ld [

pb

ar/

p]

Ir, d=3mm,rms=0.1mm

Horn, I = 0.4 MA


0.0E+00

2.0E-06

4.0E-06

6.0E-06

8.0E-06

1.0E-05

1.2E-05

1.4E-05

1.6E-05

1.8E-05

2.0E-05

2.2E-05

2.4E-05

2.6E-05

2.8E-05

3.0E-05

4 6 8 10 12 14 16 18 20

target length [cm]

yie

ld [

pb

ar/

p]


Ni, d=3mm, rms=0.62mm


0.0E+00

2.0E-06

4.0E-06

6.0E-06

8.0E-06

1.0E-05

1.2E-05

1.4E-05

1.6E-05

1.8E-05

2.0E-05

2.2E-05

2.4E-05

2.6E-05

2.8E-05

3.0E-05

4 6 8 10 12 14 16 18 20

target length [cm]

yie

ld [

pb

ar/

p]



Horn, I = 0.4 MA


0.0E+00

2.0E-06

4.0E-06

6.0E-06

8.0E-06

1.0E-05

1.2E-05

1.4E-05

1.6E-05

1.8E-05

2.0E-05

2.2E-05

2.4E-05

2.6E-05

2.8E-05

3.0E-05

4 6 8 10 12 14 16 18 20

target length [cm]

yie

ld [

pb

ar/

p]





0.0E+00

2.0E-06

4.0E-06

6.0E-06

8.0E-06

1.0E-05

1.2E-05

1.4E-05

1.6E-05

1.8E-05

2.0E-05

2.2E-05

2.4E-05

2.6E-05

2.8E-05

3.0E-05

4 6 8 10 12 14 16 18 20

target length [cm]

yie

ld [

pb

ar/

p]




Horn, I = 0.4 MA

Experimental data from CERN:A 36 mm/1.3 MA lens gave a 30% higher yield (with

nominal production beam) compared to a 0.4 MA horn.(with a target optimized for the Li lens)

The Production TargetThe Production Target

Al block

Ti window

inside: Ni rod (r = 0.15 cm, l = 10 cm) within graphite cylinder (r = 1 cm)

air cooling

Target StationTarget Station

The pbar SeparatorThe pbar Separator

240 mm mradDp/p = ± 3 %

CR-type magnets

Pbar Target Building: Horizontal CutPbar Target Building: Horizontal Cut

8 m

Pbar Target Building: Vertical CutPbar Target Building: Vertical Cut

8 m

Dose rates around the pbar targetDose rates around the pbar target

170 m

Equivalent dose rates during operationEquivalent dose rates during operation

Induced Activity after Shut-DownInduced Activity after Shut-Down

airplane at 12000 m

InducedInduced Activity after Shut-Down Activity after Shut-Down

Operation on air for 20 m after the target.pbar losses are about 5 % when He bags are used.

Target Exchange (target on air!)Target Exchange (target on air!)

Target StationTarget Station

Hot CellHot Cell

Target ExchangeTarget Exchange

target station

tunnel

ground level

Life time doses for the magnet coilsLife time doses for the magnet coils


20 MGy 50 MGy

50 MGy

Polyimide insulation required


J-PARC::1) Polyimide resin insulation (PI) for up to 100 MGy;2) Mineral insulation magnet cables (MICs) with larger cross sections for higher radiation dose up to 100 GGy.

Approximately 20 polyimide insulation magnets and 10 MICmagnets were designed. The fabrication started in 2005.

The stranded conductors impregnated by the polyimide resin to form the coil

status of the fair pbar source k. knie may 3, 2011

Documents