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Calculations of wakefields for the LHCb VeLo.

Olga Zagorodnova Desy Hamburg April 8, 2015

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Longitudinal wake potential (30m) for CATIA model.

Tapers with slots

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Different sets of the meshes.

Δ x y Δ z

Mesh 1 1mm 1mm 2mm

Mesh 2 0.5mm 0.5mm 2mm

Mesh 3 0.2mm 0.5mm 2mm

Mesh 4 0.5mm 0.2mm 2mm

Mesh 5 0.5mm 0.5mm 1mm

Mesh 6 0.2mm 0.5mm 1mm

Mesh 7 0.5mm 0.35mm 1mm

Mesh 8 0.5mm 0.2mm 1mm

Mesh 9 0.2mm 0.5mm 0.5mm

Mesh 10 0.4mm 0.4mm 0.5mmimpossibly

The calculations were performed for different beam positions:1. x=0, y=0; 2. x=1.5mm, y=0; 3. x=0, y=1.5mm

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=0.00012 V/pC

Longitudinal wake potential (10m), was calculated for different mesh properties and presented in region from -0.5m to 0.5m.Beam position – on axis. Bunch length is 7.5cm.

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Longitudinal wake potential (10m), was calculated for different mesh properties and presented in region from -0.5m to 10m.Beam position – on axis. Bunch length is 7.5cm.

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Longitudinal wake potential (10m), was calculated for different mesh properties and presented in region from -0.5m to 0.5m.Beam position – on axis. Bunch length is 7.5cm.

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Longitudinal wake potential (10m), was calculated for different mesh properties and presented in region from -0.5m to 10m.Beam position – on axis. Bunch length is 7.5cm.

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Real part of the longitudinal impedance.

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Imaginary part of the longitudinal impedance.

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X – component of the transverse wake potential for different mesh properties.Beam position – on axis. Bunch length is 7.5cm.

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X – component of the transverse wake potential for different mesh properties.Beam position – on axis. Bunch length is 7.5cm.

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Y – component of the transverse wake potential for different mesh properties.Beam position – on axis. Bunch length is 7.5cm.

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Y – component of the transverse wake potential for different mesh properties.Beam position – on axis. Bunch length is 7.5cm.

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Longitudinal wake potential for different mesh properties.Beam position – x = 1.5mm, y=0. Bunch length is 7.5cm.

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Longitudinal wake potential for different mesh properties.Beam position – x=0, y=1,5mm. Bunch length is 7.5cm.

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X – component of the transverse wake potential for different mesh properties.Beam position – x = 1,5, y = 0. Bunch length is 7.5cm.

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X – component of the transverse wake potential for different mesh properties.Beam position – x = 0, y = 1,5. Bunch length is 7.5cm.

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X – component of the transverse wake potential for different mesh properties.Beam position – x = 0, y = 1,5. Bunch length is 7.5cm.

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Y – component of the transverse wake potential for different mesh properties.Beam position – x = 1,5, y = 0. Bunch length is 7.5cm.

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Y – component of the transverse wake potential for different mesh properties.Beam position – x = 0, y = 1,5. Bunch length is 7.5cm.

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Y – component of the transverse wake potential for different mesh properties.Beam position – x = 0, y = 1,5. Bunch length is 7.5cm.