STUDIES OF ENERGY RECOVERY LINACS AT ... - CASA
STUDIES OF ENERGY RECOVERY LINACS AT ... - CASA
STUDIES OF ENERGY RECOVERY LINACS AT ... - CASA
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5.1 Successive frames in time (progressing from left to right) from a movie<br />
of the synchrotron light monitor in the second endloop at the onset<br />
of BBU. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113<br />
5.2 The Schottky diode assembly showing the directional coupler, attenuator<br />
and Schottky diode. . . . . . . . . . . . . . . . . . . . . . . . . 115<br />
5.3 Schematic of the experimental setup for simultaneously measuring<br />
the HOM power and voltage from a particular cavity. . . . . . . . . . 117<br />
5.4 A screen shot of an oscilloscope showing the HOM voltage (red) and<br />
power (blue) of the 2106.007 MHz HOM in cavity 7 of zone 3 during<br />
BBU. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117<br />
5.5 FFT of a pure 2106.007 MHz signal (top) and FFT of the HOM<br />
voltage from cavity 7 during BBU (bottom). . . . . . . . . . . . . . . 118<br />
5.6 Illustration to show the effect of sideband frequencies driving otherwise<br />
stable modes unstable. . . . . . . . . . . . . . . . . . . . . . . . 120<br />
5.7 The output from simulations of the HOM voltage squared for 4 modes.<br />
The bunch repetition frequency is 1497 MHz and the sidebands generated<br />
by 2106 MHz do not drive the other modes. . . . . . . . . . . 121<br />
5.8 The output from simulations of the HOM voltage squared for 4 modes.<br />
The bunch repetition frequency is 37.425 MHz and the sidebands<br />
generated by 2106 MHz resonantly drive the 1881 MHz and 1786 MHz<br />
modes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121<br />
5.9 Signal from a beam current monitor at the time of a BBU induced<br />
machine trip. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125<br />
5.10 Schematic of the experimental setup used for the cavity-based beam<br />
transfer function measurement. . . . . . . . . . . . . . . . . . . . . . 126<br />
5.11 The resonance curve for the 2106 MHz HOM as a function of average<br />
beam current with nominal, decoupled optics. . . . . . . . . . . . . . 127<br />
5.12 A plot of 1/Qeff versus the average beam current from the data in<br />
Fig. 5.11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128<br />
5.13 The resonance curve for the 2114 MHz HOM as a function of average<br />
beam current with nominal, decoupled optics. . . . . . . . . . . . . . 129<br />
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