PS2-Inj/Extr StraightTunability, constraints,…

Brennan and Wolfgang

PS2 Meeting, 12-May ‘10

PS2-LSS 2

Outline

• Optics and Scheme

• Constraints on phase advances, beta, dispersion

• Tunability

• Magnets

• Summary

6-May '10

PS2-LSS 3

OpticsEKES MSIS EKD1-D4IK EK

Start values: βx=54 m, βy=15 m

Working point:0.76/0.55

6-May '10

PS2-LSS 4

LSS schematicallyElement Magnetic length [m] Strength [mrad]

IS 0.8 60

IK 0.9 6.8

EK1 3.1 1.2

ES 3.8 0.8

EK2 - -

MS 7.5 53.1

EK3 1.7 0.65

6-May '10

108 m

EK1 EK3ES MSIKIS EK2

40 75

180

88

PS2-LSS 5

Constraints• Minimum drift for H-: 24 m• μx between MTE extr. bumpers: k*180 +/-20

• μx between ES and MS: 90 + k*180 +/-20

• μx between MTE extr. kicker and MS: 90 + k*180 +/-20

• μx between FInj kicker and Finj septum: 40 + k*180 +/-10• max. quadrupole gradient: 15 T/m• βxy ‘reasonable’ - below ~60 m • dispersion-free• Two injection optics versions:

– Foil inj. with bxy ca. 20 m and axy ~0 at foil– Laser inj. with by as low as possible and axy ~0 at IR– Extraction optics equals foil injection optics

• Path from Laser inj. to extr. optics with LSS μx constant

6-May '10

PS2-LSS 6

Phase advances

• working point: 0.76/0.55

• no matching constraints on phase advance between elements

• horizontally and vertically tuned by +/-0.1 with flexibility in beta start of +/- 1.5 m

6-May '10

Tuned along diagonal from Qx/Qy min to Qx/Qy max

PS2-LSS 7

Length of BT elements vs tune

6-May '10

EK1 close to the limit of 4 m for high tune

PS2-LSS 8

Quadrupoles• 2 quads with:

– length: 1.6 m– normal (arc) aperture of 65 mm– max. gradient (from magnet design): 16 T/m

• 8 quads with:– length: 2.4 m, width: 1.3 m– enlarged aperture of 78 mm (arc: 65 mm)– max. gradient (from magnet design): 15 T/m

6-May '10

PS2-LSS 9

Quadrupole gradients

6-May '10

Tuned along diagonal from Qx/Qy min to Qx/Qy max

PS2-LSS 10

MQD2 gradient

6-May '10

PS2-LSS 11

Summary I• LSS: doublet structure, length of 108 m• 2 optics variants:

– foil injection and extraction– Laser injection

• Path for Laser inj optics:– 15 m for βy feasible within constraints and continuous tuning path

– 9 m for βy difficult (quad signs changing)

• 2 quadrupole types, 5 power converter families• Quad gradients

– below 15 T/m for change-over quad– below 10 T/m for doublet quads

6-May '10

PS2-LSS 12

Summary II• Optics tunability of +/- 0.125

• Tunability of +/- 0.1 for both planes with phase advances constraints between inj/extr elements:– +/-20 deg between EK1 – EK3, ES – MS and EK1 – MS– +/-10 deg between fast injection septum and kicker

• Flexibility to change beta start values by +/- 1.5 m

6-May '10