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Superconducting RF Cavities

(Version 1.3)

b = 0.61  Section

Cavity geometry

33 cavities, 11 cryomodules

Microphonics:

  • Normal operation: Gaussian distribution with s = 9 Hz.
  • Noisy operation: Gaussian distribution with s = 17 Hz, contol system capable to 6 s

Peak surface field:

  • Reference design: 27.5 MV/m for all cavities.
  • JLab goal: Uniform distributuion centered about 27.5 MV/m, + 2.5 MV/m
  • Expected operation mode: One cavity missing

Ep / E0 = 1.87 ( average over cavity )

Bp / Ep [mT/(MV/m)] = 2.1 (all cells)

R / Q = 279 Ohm at b =0.61, = 303 Ohm at b =0.61

G = 176.533 Ohm ( = geomtery factor Q x R)

k [%] = 1.61 (cell-to-cell coupling coefficient)

QBCS @ 2K = 27.36 x 109

Frequency [MHz] = 805

Field Flatness [%]= 2.5

Lorentz-force detuning KL70 = -2.9 Hz/(MV/m)2 (Lorentz detunning cofficient with stiffeners at 70 mm)

KL80 = -3.4 Hz/(MV/m)2 (Lorentz detunning cofficient with stiffeners at 80 mm)

Nb thickness = 3.8 mm

Active cavity length = 0.68151

External Q = 5 x 105, + 20%

b = 0.81093 Section

48 cavities, 12 cryo modules (tunnel has space for 21 cryo modules)

Lorentz detuning: K = 1 Hz/(MV/m)2

Microphonics:

  • Normal operation: Gaussian distribution with s = 9 Hz.
  • Noisy operation: Gaussian distribution with s = 17 Hz, contol system capable to 6 s

Peak surface field:

  • Reference design: 35 MV/m for all cavities.
  • JLab goal: 35 MV/m, +2.5, -7.5 MV/m 2.5 MV/m
  • Expected operation mode: One cavity missing

Ep / Eo = 1.69 (interior cell)

Bp / Ep =  2.15 (mT/MV/m)

Active cavity length = 0.90496

External Q = 5 x 105, + 20%

QBCS at 2 K ~ 34.8 x 109


Contact

John Galambos, (865-576-5482)


Updated Thursday, 07-Jun-2007 15:07:01 EDT - 2,395