Smooth approximation model of dispersion with strong space charge for continuous beams

Bernal, S.; Beaudoin, B.; Koeth, T.; O'Shea, P.G.

doi:10.1103/physrevstab.14.104202

Cited by 4 publications

(1 citation statement)

References 14 publications

(36 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…II, longitudinal space charge alters the energy at the beam ends when no longitudinal confining fields are used [4,11,20,21]. Ring dispersion then causes a centroid displacement that is correlated axially along the length of the bunch [22]. In order to image this motion, we use a combined 2.4 ns phosphor screen and 3 ns gated 16-bit PIMAX2 ICCD camera installed at RC15.…”

Section: Sliced Phosphor Screen Measurements Along a Beammentioning

confidence: 99%

Tune variation and transverse displacement as a diagnostic for profiling beam energy

Beaudoin

Kishek

2013

Phys. Rev. ST Accel. Beams

Self Cite

View full text Add to dashboard Cite

In this paper we describe two methods that demonstrate an energy evolution at the ends of a long bunch. The first method is a nondestructive diagnostic that extends the response matrix technique, to provide insight into the time-sliced transverse behavior of a coasting bunch in a ring. This method uncovers intense beam physics from the resulting longitudinal energy variations at the ends of a rectangular bunch. Measurements of the tune profile, using this method, agree with analytical predictions resulting in a percent error of 0.32% and 2.45% (head and tail respectively). Measurements and calculations presented in this paper are presented for a beam with an intensity of 0.901 (beam current of 21 mA). The head and the tail tunes, averaged over four ring chambers, also illustrate the intensity variation axially along the bunch. This is exhibited through tune-shift measurements at the ends of the bunch. As confirmed through calculations, the measured tune shift at the head is smaller than the tail. This results from the sum of both the transverse coherent tune shift from image forces with the component from longitudinal space charge. The sum of the two components produces a smaller tune shift at the head of the beam and a larger tune shift at the tail. The second method presented in this paper optically illustrates the centroid ''cork-screwing'' motion within the beam ends, at a single location on the ring. The motion is resolvable using this diagnostic since it is capable of axially time-slicing regions of the beam with different energies. The difference between the two methods presented is that the first is a nondestructive diagnostic that can be extended to multiple turns whereas the second method is a destructive first turn imager.

show abstract

Section: Sliced Phosphor Screen Measurements Along a Beammentioning

confidence: 99%

Tune variation and transverse displacement as a diagnostic for profiling beam energy

Beaudoin

Kishek

2013

Phys. Rev. ST Accel. Beams

Self Cite

View full text Add to dashboard Cite

show abstract

Beam matching with space charge in energy recovery linacs

Khan

Hug

Stoll

2019

Nuclear Instruments and Methods in Physics Research Section A:

View full text Add to dashboard Cite

Coherent dispersion effects in 2D and 3D high-intensity beams

Yuan,

Franchetti

2023

Physics of Plasmas

View full text Add to dashboard Cite

Both space charge and dispersion have an effect on high-intensity beams in circular accelerators or transport sections with bending magnets and may lead to emittance growth and beam loss. In this paper, we present an investigation of the combined effect of dispersion and space charge on two-dimensional beams deepening the understanding of the 120° dispersion-induced instability. We also investigate the 90° envelope instability, which in the absence of the dispersion, mixes the confluent and parametric resonances. We show here that the presence of dispersion and high intensity breaks the overlapping and separates the two resonances. Furthermore, we study the beam dynamics of three-dimensional bunched beams and find the surprising result that the synchrotron motion can split the dispersion mode into two equally separated “sideband” modes according to the beam intensity and synchrotron frequency.

show abstract

Smooth approximation model of dispersion with strong space charge for continuous beams

Cited by 4 publications

References 14 publications

Tune variation and transverse displacement as a diagnostic for profiling beam energy

Tune variation and transverse displacement as a diagnostic for profiling beam energy

Beam matching with space charge in energy recovery linacs

Coherent dispersion effects in 2D and 3D high-intensity beams

Contact Info

Product

Resources

About