Accelerator Vacuum Systems at DESY M Seidel DESY

Accelerator Vacuum Systems at DESY M. Seidel, DESY Workshop on Vacuum Systems of Synchrotron Light Sources Barcelona, 12. -13. 9. 2005

Outline n n n overview on operating accelerators DORIS II new light source project PETRA III XFEL DESY vacuum expertise

Overview DESY - Leptons LINAC II <0. 65 Ge. V, 50 m S-Band Cu-structures, lumped pumps PIA 0. 45 Ge. V, 29 m Steel DESY II 0. 45 -7 Ge. V, 293 m thin walled (0. 3 mm) steel chamber DORIS 4. 5 Ge. V, 289 m copper, int. Ion-Getter-, NEG-Pumps, one NEG coated undulator chamb. (linac) PETRA II 7 -12 Ge. V, 2. 3 km aluminum, int. ion-getter pumps HERA-e 12 -27. 5 Ge. V, 6. 3 km copper, int. NEG pumps TTF 0. 8 Ge. V, 0. 3 km (linac) sc. L-Band structures, particle free!

Overview DESY - Protons LINAC III 50 Me. V(kin), 34 m Alvarez Structures (linac) DESY III 0. 05 -7. 5 Ge. V/c, 293 m stainless steel, lumped pumps PETRA II 7. 5 -40 Ge. V, 2. 3 km aluminum, int. Ion-Getter pumps, p-specific bypass (RF) HERA-p 40 -920 Ge. V, 6. 3 km cold, sc. magnets (5 T), lumped pumps, NEG in sophisticated IR

TTF DORIS DESY II/III LINACS

LINAC II e+/e- S_Band Accelerator Technology - copper structures, 2. 998 GHz, inductively brazed

DESY II (e+/-), DESY III (p) DESY II chamber, d=0. 3 mm

PETRA II • e+/-: 12 Ge. V • p: 40 Ge. V • ρ: 200 m • L: 2304 m

HERA (e+/- 27. 5 Ge. V, p 920 Ge. V) proton ring (sc) electron ring

TESLA TEST Facility – VUV FEL n Overall system n 360 m beam vacuum n n 60 m cold (2 K), 3 sections 300 m room temperature 50 m coupler vacuum 60 m isolation vacuum

DORIS – Synchrotron Radiation Source DORIS: • 1974 established, e+/e- collisions • since 1981 parasitic SR usage • since 1993 exclusive SR usage • 4, 45 Ge. V, 289 m • 9 insertion devices • tot. 36 experimental stations • copper vacuum chambers • integrated ion getter pumps; Ti sublimation pumps • typical beam lifetime 15 -25 hours

DORIS storage ring dipole beamline wiggler NEG coated ss. beampipe

PETRA III – new SR Source Plan: rebuild existing PETRAII; completely new vacuum; partial use of old magnets • E: 6 Ge. V, I: 100 m. A • C: 2. 3 km; ρ: 195 m • one new octant with 8 undulators; 13 high brilliance beamlines • small emittance via damping wigglers

PETRA III Project - Arc pumped via NEG strip n n rebuild starting 7/07; HERA stops(!) operation 09 one octant with DBA cells, undulators, steel chambers and copper absorbers 7 octants use old magnets with new coils, aluminum chambers optimized for minimum new PETRAmaximum III profile, stability aperture emittance, 40 x 80 mm 2, bend. radius 196 m

PETRA III – Experimental Octant copper absorbers BPM valve dipoles one cell shown – 8 cells planned undulators corrector magnet

PETRA III – Experimental Octant Al undulator chamber steel chamber w. NEG pump Cu absorber 2 outlets undulator ch. outside view

XFEL Project n n sc. TESLA accel. structures (1. 3 GHz), about 1000 cavities operation from 2012 1. 5 km cold vacuum, isolation vacuum, tot. 700 m(!) undulator, >1 km beam distribution, particle free preparation challenging: undulator vacuum – small gap, resistivity, roughness… collimator section – has to withstand mis-steered beam p-profile w/o int. pump proposal of undulator beam tube

DESY Vacuum Expertise n n n cold vacuum systems (HERA-p, TTF) copper brazing technology (HERA-e, . . ) particle free preparation (TTF, XFEL. . ) S-Band Lin. Acc. → inductive brazing, precision machining of cups RF guns, Nb e-beam welding, custom sputtering, NEG pumped systems, operation of large systems etc…