Preliminary Electron Transportation Channel Project for EIC Facility

(FAIR, Germany)

Dmitry BerkaevBudker Institute of Nuclear Physics, Russia, 630090, Novosibirsk, Lavrentev ave., 11

Novosibirsk State University, Russia, 630090, Novosibirsk, Pirogova str., 2

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Electron-Antiproton RingM

ain

EAR

Para

met

ers (

500

MeV

)

b-functions at Injection Point:bx = 226 cm, ax = -1.43bz = 159 cm, az = -0.1yz = 54 cm

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500 MeV Linac

General View (Figure of P. Logatchev).

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Beam Injection into EAR

Injection at x = 16 mm

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Beam Transportation

Four 38O magnets and 21.2O septum beam transportation channels. Length ~21.8 m.

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Beam Focusing

Focusing with 13 Quads – two aims: matching of beta-functions of the ring and channel and avoid large beam sizes.

b, c

my

, cm

Max gradient – 8 kGs/cm

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Beam sizes in the Channelx, cm

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Magnetic Elements• 38o Bending Magnet

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Magnetic Elements• 21.2o Septum-Magnet

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Magnetic Elements• Quads and Steering Coils

Quads and steering coils are the same as in the Linac (Figures of P. Logatchev)

Max gradient – 8 kGs/cm

Max Field– 0.5 kGs

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Beam Position Monitors

7 BPMs along the channel

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Beam Position MonitorsSecondary Emission MonitorWall Current Monitor

Destructive,тransparency ~98-99%

No beam shape,Nonlinear at largedeviations

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Difficulties•Injection in non-zero dispersion point

•Injection from outside the ring

•Large Linac energy spread (1%).

Possible solution: Rise the beam above the EAR and inject in “correct” place…

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Conclusion• Preliminary design of injection scheme for EAR (FAIR EIC Project) is presented. It is shown

that injection can be done into the straight section before the bending magnet .

• Kicker of feasible parameters (50 kV, two plates, 52 cm) can store injecting beam in EAR at the maximum energy of 500 MeV.

• Preliminary geometry of electron injection channels for EAR (FAIR EIC Project) is presented. Total length of the channel is about 21.8 meters. Injection occurs into straight section before bending magnet in horizontal plane with 10 kGs septum-magnet.

• Four main 9.94 kGs magnets provide beam transportation from Linac to EAR. Preliminary estimation of these magnets shows achievable parameters of fields and power consumption.

• Beam focusing done with 13 Quads with 8 kGs/cm gradient.

• 7 BPMs seems to be used in the channel.

• Injection occurs at the point with non-zero dispersion, so the next task is to simulate injection with taking into account energy deviation questions.