03.07.2013 Views

mode - CERN Accelerator School

mode - CERN Accelerator School

mode - CERN Accelerator School

SHOW MORE
SHOW LESS

You also want an ePaper? Increase the reach of your titles

YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.

Longitudinal g dynamics y<br />

→ Ions are accelerated around a<br />

(linac=negative) synchronous phase.<br />

→ Particles around the synchronous one<br />

perform oscillations in the longitudinal<br />

phase space.<br />

→ FFrequency of f small ll oscillations: ill ti<br />

ω<br />

2<br />

l<br />

= ω<br />

2<br />

0<br />

( −ϕ<br />

)<br />

qE0T<br />

sin<br />

2<br />

2π<br />

mc βγ<br />

→ Tends to zero for relativistic particles γ>>1.<br />

→ Note phase damping of oscillations:<br />

Δϕ<br />

=<br />

const<br />

3/<br />

4<br />

( β γ )<br />

3<br />

λ<br />

3/<br />

4<br />

ΔW = const × ( β γ )<br />

At relativistic velocities phase oscillations stop, the<br />

beam is compressed in phase around the initial phase. phase<br />

The crest of the wave can be used for acceleration.<br />

35

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!