Successful Completion of Six-Cavity Test with the HINS Accelerator

Six-Cavity Beam Line

• HINS six-cavity beam line constructed on the east side of MDB.

• Beam line can test concept of driving multiple cavities with a single RF amplifier.

• Significant cost savings may be realized by using fewer RF power amplifiers.

Vector (I/Q) Modulator:Modulates phase and amplitude independently:

With = (2 - 3)/2 = (2 + 3)/2

Output power ~ cos2()Output phase ~

Input →

Output :←to circulator and

cavity

1 2

34

2

3

Phase Shifters

Four Port Hybrid

water load

circulator

LLRF System Setup

• RF Feedback on RFQ amplitude and phase• Feed forward learning correction of Ferrite Vector Modulators

Vector Modulator Configuration

Cavity Probe Signals• RFQ RF Feedback ON• FVM Control OFF• Beam ON (7 mA)

*Buncher 1, Cavity 2, and Cavity 3 were detuned so that the FVM’s have enough dynamic range to compensate disturbances.

Magnitude (MV) Phase (degrees)

Beam Off at 300 us

*Cavity 1 FVM correction did not completely converge due to limited dynamic range of FVM

Cavity Probe Signals• RFQ RF Feedback ON• FVM Control ON• Beam ON (7 mA)

Magnitude (MV) Phase (degrees)

RFQ Magnitude and Phase Regulation• RFQ RF Feedback ON• FVM Control ON• Beam ON

Pulse to Pulse Average of RMS Error(50 Pulses)

Pulse to Pulse Average of RMS magnitude Error = 0.0207%

Pulse to Pulse Average of RMS phase Error = 0.0147 degrees

RFQ Magnitude RFQ Phase

+/-1%

Beam Energy Stability

• Difference between green and red trace show time-of-flight between diagnostic line BPMs.

• Energy scale is ~1.4keV/degree for time of flight BPM measure-ments. Plot shows noise level of about 10keV for 3MeV beam.

Contributors• AD• Bob Webber• Jim Steimel• Bruce Hanna• Vic Scarpine• Alex Chen• Bruce Popper• Maurice Ball• Abhishek Deshpande• Dave Peterson• Ralph Pasquinelli• Elmie Evans-Peoples• Wai-Ming Tam• Brian Chase• Julien Branlard• Paul Joireman• Ed Cullerton• Vitale Tupikov• Philip Varghese• Chris Jensen• Kevin Martin• Steve Hays

• APC• Robyn Madrack• Dave Wildman• Henryk Piekarz• Jean-Paul Carneiro•  Al Moretti• Nikolai Mokhov

• TD• Giorgio Apollinari• Gennady Romanov• Timergali

Khabiboulline• Iouri Terechkine• Leonardo Ristori• Tom Page• Tom Nicol

• AD• Howie Pfeffer• George Krafczyk• Mike Kucera• Brad Claypool• Jim Patrick• Andrey Petrov• Bill Marsh• Charlie Briegel• Dennis Nicklaus• Denise Finstrom• Carl Schumann• Stan Johnson• Todd Johnson• Aisha Ibrahim• Roger Tokarek• Duane Voy• Nathan Eddy• Peter Prieto• Andrea Saewert• Lionel Prost

HINS RF Distribution