Storage Rings in the FAIR Project at GSI

Storage Rings in the FAIR Project at GSI

P. Beller

November 4, 2004

P. Beller, November 4, 2004

• Physics with Rare Isotope Beams• Antiproton Physics• Atomic Physics with Highly charged Heavy Ions

Physics at the New Storage Rings

• Stochastic Precooling• Electron Cooling• Accumulation• Fast Deceleration (100 - 500 MeV/u)• Deceleration to Low Energies• Fast/Slow Extraction to Cave • In-Ring Experiments• Isochronous Mass Measurements

Physics at the New Storage RingsPhysics at the New Storage Rings

Required Properties of the Storage RingsRequired Properties of the Storage Rings


The FAIR Project

SIS100/300

CR/RESR

NESR

HESR


CR/RESRBunch rot., ad. debunching, stoch. precooling

Pbar-targetSuper-FRS

SIS 100

Pb

ar r

ein

ject

ion

Operation Schemes

RIB Physics

Up to 11012 ionsper 50 ns bunch

max. 5109 RIs per cycle at 740 MeV/u

Fast deceleration to 100 - 400 MeV/u

Pbar Physics

Up to 2.51013 protonsper 50 ns bunch

1108 pbars per cycle at 3 GeV

Accumulation of up to51011 pbars

Atomic Physics

Up to 11010 ions

NESRElectron cooling, deceleration to E < 30 MeV/u, in-ring-experiments

(gas-jet-target, e-A collisions, electron target), fast and slow extraction


The Storage Rings

from Super-FRS/pbar-Separator

to atomic physics cave,

HITRAP,FLAIR

NESRe--cooling

deceleration RESRpbar accumulationRIB deceleration

Collector Ringbunch rotation

adiabatic debunchingfast stochastic cooling

isochronous mode

electron ring


Layout of the RESR Lattice

Main tasks:Pbar accumulation

Fast deceleration of RIBs

Circumference 245.5 mMax. bend. power 13 Tm


RESR Beam Envelopes and Dispersion Function

Transverse acceptance [mm mrad] 80/35

Momentum acceptance [%] ±1

Horizontal/vertical tune 3.8/3.3

Transition energy 3.62

Maximum dispersion [m] 8


RESR Beam Parameters

RI Beam parametersRI Beam parameters

Energy after deceleration (1 T/s) [MeV/u] 100 - 740

Transverse emittance after deceleration [mm mrad] 0.5 - 1.5

Momentum spread after deceleration0.5 -

1.110-3

pbar Beam parameterspbar Beam parameters

Energy [GeV] 3

Accumulation rate [pbar/h]

Accumulation time [h]

Transverse emittance after deceleration [mm mrad]

710-10

0.5 - 2

5 – 13

Momentum spread after deceleration 1 - 2.610-3


0

0.5

1

1.5

2

0 0.5 1 1.5 2 2.5 3 3.5

t [s]

Dip

ole

fie

ld [

T]

RESR Cycles

Duration Dipole field Remark

< 1 s 1.1 – 1.6 T Injection at 740 MeV/u

ca. 1 s Ramp with 1 T/s to 100 – 400 MeV/u, max B = 1.1 T

< 1 s 0.35 – 0.5 T Extraction

< 1s – 5 min 0.35 – 0.5 T Waiting for next Injection

ca. 1 s Ramp with 1 T/s to injection level

pbar Operation: static operation at maximum field level

RIB Operation

Example for a short RIB cycle

approx.

50 % pbar

50 % RIB

operation


RESR Magnet Parameters

Numbers 24

Maximum field 1.6 T

Minimum field 0.35 T

Ramp rate 1 T/s

Maximum B 1.1 T

Bending radius 8.125 m

Deflection angle 15°

Effective length 2.128 m

Useable gap width 250 mm

Useable gap hight 70 mm

Real gap hight (heating) 90 mm

Field quality 110-4

Numbers 44

Maximum field gradient 4.6 T/m

Minimum field gradient 1.01 T/m

Maximum pole field 0.6 T

Minimum pole field 0.13 T


Useable horizontal aperture 300 mm

Useable vertical aperture 180 mm

Aperture radius 128 mm

Field quality 510-4

DipolesDipoles Quadrupoles (ESR-type)Quadrupoles (ESR-type)


Layout of the NESR Lattice

NESR:Circumference 222.11 mMax. bending power 13 TmRamp rate 1 T/sEnergy range: Ions 4 – 840 MeV/uPbar 30 MeV – 3 GeV

NESR:Circumference 222.11 mMax. bending power 13 TmRamp rate 1 T/sEnergy range: Ions 4 – 840 MeV/uPbar 30 MeV – 3 GeV

Electron ring:Circumference 45.22 mElectron energy 200-500 MeV

Electron ring:Circumference 45.22 mElectron energy 200-500 MeV


Beam Envelopes and Dispersion Function

Horizontal/vertical acceptance [mm mrad] 160/100

Momentum acceptance [%] ±1.75

Horizontal/vertical tune 3.4/3.2

Transition energy 5.74

Maximum dispersion [m] 7.24


Separation of Two Uranium Charge States

Maximum dispersion [m] 7.24

Horizontal beta function in the arc [m] 6.72

Horizontal/vertical angular acceptance [mrad] 8.4/1.7

Separation of U92+/ U91+ (h = 0.1 mm mrad) [mm] 79

Separation of U92+/ U91+ (h = 10 mm mrad) [mm] 63

Momentum resolution (h = 0.1 mm mrad) 210-4


NESR Beam Parameters

Energy range (A/Z=2.7) (Ramp Rate 1 T/s) [MeV/u] 4 - 740

Cooling time constant (for U92+-ions) [s] 0.3 - 0.5

Transverse emittance after cooling [mm mrad] 0.1

Momentum spread after cooling 110-4

Luminosity at internal gas target for 132Sn [cm-2 s-1] 61028

pbar Beam parameterspbar Beam parameters

Ion (RI or stable) Beam parametersIon (RI or stable) Beam parameters

Energy range (Ramp Rate 1 T/s) [MeV] 30 – 3000

Cooling time constant (at 840 MeV) [s] 5 – 25

Transverse emittance after cooling [mm mrad] 1

Momentum spread after cooling 110-4


NESR Cycles (pbar)


< 1 s 1.6 T Injection at 3 GeV

1 s Ramp with 1 T/s to 840 MeV, B = 1 T

10 - 50 s 0.6 T Electron cooling

0.5 s Ramp with 1 T/s to 30 MeV, B = 0.5 T

ca. 5 s 0.1 T Electron cooling

< 1 s 0.1 T Extraction

10 min 0.1 T Waiting before next Injection

1.5 s Ramp with 1 T/s to injection level

pbar cycle with deceleration to 30 MeV (approx. 25 % of operating time)


0

0.5

1

1.5

2

0 2 4 6 8 10 12

t [s]

Dip

ole

fie

ld [

T]

NESR Cycles (RIB/Highly Charged Heavy Ions)


1 -30 s < 1.6 T Injection at 100 -740 MeV/u, electron cooling

< 1.5 s Ramp with 1 T/s to 3 – 100 MeV/u, max. B = 1.5 T

ca. 3 s > 0.06 T Electron cooling

< 1 s > 0.06 T Extraction (experiments in external cave)

< 15 min > 0.06 T In ring experiments, waiting for next injection

< 1.5 s Ramp with 1 T/s to injection level

Example for deceleration to 3 MeV/u and subsequent fast extraction

approx. 75 % RIB operation / 25 % atomic physics with highly charged ions


NESR Magnet Parameters

Numbers 24

Maximum field 1.6 T

Minimum field 0.06 T

Ramp rate 1 T/s

Maximum B 1.5 T

Bending radius 8.125 m

Deflection angle 15°


Useable gap width 250 mm

Useable gap hight 70 mm

Real gap hight (heating) 90 mm

Field quality 110-4

Numbers 32 (8/24)

Maximum field gradient 3.95/4.8 T/m

Minimum field gradient 0.15/0.18 T/m

Maximum pole field 0.51/0.61 T

Minimum pole field 0.019/0.023 T

Effective length 1.24/0.82 m

Useable hor. aperture 300 mm

Useable vert. aperture 180 mm

Aperture radius 128 mm

Field quality 510-4

DipolesDipoles Quadrupoles (ESR-type)Quadrupoles (ESR-type)


Summary of Dipole Ramp Data

Maximum field at injection 1.6 T

Minimum field after deceleration 0.06 T

Maximum B 1.5 T

Ramp rate 1 T/s

Cycle time 5 s -15 min

Time at injection level 1 – 30 s

Time at intermediate level 10 – 50 s

Time at extraction level 1 s – 15 min

RESR: 50 % of operating time will be static operation at maximum field level (pbar)

NESR: more than 25 % of operating time will be operation with low duty cycle (pbar + atomic physics with highly charged heavy ions)

RESR and NESR Dipoles will be

identical!

Documents

Storage Rings in the FAIR Project at GSI