Orbit distortion and beam tilt caused by transverse wake fields

Technical Report · Tue Sep 01 00:00:00 EDT 1981

DOI:https://doi.org/10.2172/6788802· OSTI ID:6788802

Chao, A W; Kheifets, S

As particle bunch passes through a region with a transverse impedance, it generates a transverse wake electromagnetic field that is proportional to the transverse displacement of the bunch in the region. The field acts back on the bunch, causing various effects (such as instabilities) in the motion of the bunch. In this note, we study one of such effects in which a transverse impedance causes the beam to be distorted in its shape. Observed at a fixed location in the storage ring, this distortion does not change from turn to turn; rather, the distortion is static in time. To describe the distortion, let us cut the bunch longitudinally into many slices and connect the centers of charge of the slices into a curve. In the absence of transverse impedance, this curve is a straight line parallel to the direction of motion of the bunch. Perturbed by the transverse EM field, the curve becomes distorted. What we will find in this note is the shape of such a curve. We emphasize the fact that the effect we are considering is a static effect. The beam is assumed to be stable in this statically distorted state. The distortion is a result of having the bunch passing by the impedance off-centered; the produced wake then acts on the particles, causing them to follow distorted closed orbits which depend on the longitudinal positions of the particles. 10 refs., 1 fig.

• Research Organization: SLAC National Accelerator Lab., Menlo Park, CA (United States)
• DOE Contract Number: AC03-76SF00515
• OSTI ID: 6788802
• Report Number(s): SLAC-PEP-NOTE-365; ON: DE89006360
• Resource Relation: Other Information: Portions of this document are illegible in microfiche products
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
BEAM DYNAMICS
INSTABILITY
PEP STORAGE RINGS
BEAM BUNCHING
BEAM CURRENTS
BEAM EMITTANCE
ELECTRIC IMPEDANCE
EQUATIONS OF MOTION
ORBITS
CURRENTS
DIFFERENTIAL EQUATIONS
EQUATIONS
IMPEDANCE
PARTIAL DIFFERENTIAL EQUATIONS
STORAGE RINGS
430400* - Particle Accelerators- Storage Rings
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