29th June 2006 EuroFEL DS5 Feedback Carl Beard

EMMA RF Systems

29th June 2006 EuroFEL DS5 Feedback Carl Beard

Outline

• RF Cavity Design– ELBE Buncher Cavity– Redesign for larger

iris– Implications

• Costings– IOT Amplifiers– Klystron Option

29th June 2006 EuroFEL DS5 Feedback Carl Beard

ELBE RF Cavity• Cavity was designed By Andre Buchner (@ FZR)• Optimised for maximum shunt impedance• Q = 11900 (13750 calculated)• R/Q is 103 Ohm.

– This gives 60 W for 12 kV (49 W calculated).

• Water cooling is only on one side. • Frequency -0.33 kHz/W and a heating of 2 deg for

100 W • Temperature stability

– 1 deg (water) caused a frequency shift of 22 kHz.

29th June 2006 EuroFEL DS5 Feedback Carl Beard

ELBE RF Cavity (2)

29th June 2006 EuroFEL DS5 Feedback Carl Beard

Cavity Redesign

• Increase Beam pipe – Reduces shunt impedance– Increase in required RF Power– Input through N-type connector

• Increase in Cooling capacity• Decrease in RF heating• Option to add cooling to other side.• Tuning system should also scale…• Cavity geometry being re-optimised

29th June 2006 EuroFEL DS5 Feedback Carl Beard

Initial Calculations.

Rsh

0.0000E+00

2.0000E+05

4.0000E+05

6.0000E+05

8.0000E+05

1.0000E+06

1.2000E+06

1.4000E+06

1.6000E+06

1.8000E+06

2.0000E+06

20 25 30 35 40 45

Rsh

29th June 2006 EuroFEL DS5 Feedback Carl Beard

IOT Amplifier

• Proposed purchase of 8 IOT transmitters, including– IOT– Power Supplies– Drive Amplifier

• Each Amplifier powers 3 RF cavities• Fast Downtime in the event of IOT failure.• Most parts are production items• More efficient• 8 IOT transmitters is a very Large system

29th June 2006 EuroFEL DS5 Feedback Carl Beard

Klystron Option• A single High Power Klystron could power EMMA ring.• 1 item would be reduction in cost compared to the IOT

system. • Plus reduction in space• High gain device

– Smaller drive amplifier required.

• High Voltage Power Supply Required

• Replacement, equally as expensive.• Long downtime• Few Suppliers• Complicated RF distribution scheme