DOI: 10.1201/9780429434358-3
C H A P T E R 3
Orbit and trajectory
correction
CONTENTS
3.1
Accelerator components for orbit correction . . . . . . . . . . . . . . 70
3.1.1 Beam position monitors . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
3.1.2 Orbit correctors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
3.2
Beam-based alignment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
3.3
Orbit correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
3.3.1 Orbit correction with SVD . . . . . . . . . . . . . . . . . . . . . . . . . 78
3.3.2 Orbit correction with weights on BPMs . . . . . . . . . . 84
3.3.3 Other methods for global orbit correction . . . . . . . . . 86
3.3.4 Local orbit correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
The path of the beam through an accelerator lattice may be called the orbit
or the trajectory. In circular accelerators, there exists a closed beam path,
which is called the orbit. In one-pass lattices, such as linacs or transport lines,
the beam path varies from shot to shot, depending on the launching angles
and positions. The beam path in one-pass systems is the trajectory, which is
often loosely referred to as the orbit.
The beam orbit or trajectory is important to the beam performance. Most
beam applications require precise positioning of the beam in order to be effective. For example, in collider experiments, the two colliding beams have
to overlap in space for collisions to happen. In synchrotron light sources, the
electron beam orbit has to be precisely controlled for the photon beam to
be focused on the sample. In a free electron laser (FEL), trajectory errors in
the undulators not only affect the photon beam positioning on the samples,
but also can severely reduce the FEL power. Orbit or trajectory errors may
cause a reduction of the effective aperture when the beam is driven toward the
vacuum chamber and cause beam losses. In circular accelerators, orbit errors
in nonlinear magnets (e.g., sextupoles) cause optics errors and linear coupling
and can impact the nonlinear beam dynamics performance. Typically, orbit
or trajectory control is a high priority in accelerator operation.
69
C H A P T E R 3
Orbit and trajectory
correction
CONTENTS
3.1
Accelerator components for orbit correction . . . . . . . . . . . . . . 70
3.1.1 Beam position monitors . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
3.1.2 Orbit correctors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
3.2
Beam-based alignment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
3.3
Orbit correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
3.3.1 Orbit correction with SVD . . . . . . . . . . . . . . . . . . . . . . . . . 78
3.3.2 Orbit correction with weights on BPMs . . . . . . . . . . 84
3.3.3 Other methods for global orbit correction . . . . . . . . . 86
3.3.4 Local orbit correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
The path of the beam through an accelerator lattice may be called the orbit
or the trajectory. In circular accelerators, there exists a closed beam path,
which is called the orbit. In one-pass lattices, such as linacs or transport lines,
the beam path varies from shot to shot, depending on the launching angles
and positions. The beam path in one-pass systems is the trajectory, which is
often loosely referred to as the orbit.
The beam orbit or trajectory is important to the beam performance. Most
beam applications require precise positioning of the beam in order to be effective. For example, in collider experiments, the two colliding beams have
to overlap in space for collisions to happen. In synchrotron light sources, the
electron beam orbit has to be precisely controlled for the photon beam to
be focused on the sample. In a free electron laser (FEL), trajectory errors in
the undulators not only affect the photon beam positioning on the samples,
but also can severely reduce the FEL power. Orbit or trajectory errors may
cause a reduction of the effective aperture when the beam is driven toward the
vacuum chamber and cause beam losses. In circular accelerators, orbit errors
in nonlinear magnets (e.g., sextupoles) cause optics errors and linear coupling
and can impact the nonlinear beam dynamics performance. Typically, orbit
or trajectory control is a high priority in accelerator operation.
69
C H A P T E R 3
Orbit and trajectory
correction
CONTENTS
3.1
Accelerator components for orbit correction . . . . . . . . . . . . . . 70
3.1.1 Beam position monitors . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
3.1.2 Orbit correctors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
3.2
Beam-based alignment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
3.3
Orbit correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
3.3.1 Orbit correction with SVD . . . . . . . . . . . . . . . . . . . . . . . . . 78
3.3.2 Orbit correction with weights on BPMs . . . . . . . . . . 84
3.3.3 Other methods for global orbit correction . . . . . . . . . 86
3.3.4 Local orbit correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
The path of the beam through an accelerator lattice may be called the orbit
or the trajectory. In circular accelerators, there exists a closed beam path,
which is called the orbit. In one-pass lattices, such as linacs or transport lines,
the beam path varies from shot to shot, depending on the launching angles
and positions. The beam path in one-pass systems is the trajectory, which is
often loosely referred to as the orbit.
The beam orbit or trajectory is important to the beam performance. Most
beam applications require precise positioning of the beam in order to be effective. For example, in collider experiments, the two colliding beams have
to overlap in space for collisions to happen. In synchrotron light sources, the
electron beam orbit has to be precisely controlled for the photon beam to
be focused on the sample. In a free electron laser (FEL), trajectory errors in
the undulators not only affect the photon beam positioning on the samples,
but also can severely reduce the FEL power. Orbit or trajectory errors may
cause a reduction of the effective aperture when the beam is driven toward the
vacuum chamber and cause beam losses. In circular accelerators, orbit errors
in nonlinear magnets (e.g., sextupoles) cause optics errors and linear coupling
and can impact the nonlinear beam dynamics performance. Typically, orbit
or trajectory control is a high priority in accelerator operation.
69
C H A P T E R 3
Orbit and trajectory
correction
CONTENTS
3.1
Accelerator components for orbit correction . . . . . . . . . . . . . . 70
3.1.1 Beam position monitors . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
3.1.2 Orbit correctors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
3.2
Beam-based alignment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
3.3
Orbit correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
3.3.1 Orbit correction with SVD . . . . . . . . . . . . . . . . . . . . . . . . . 78
3.3.2 Orbit correction with weights on BPMs . . . . . . . . . . 84
3.3.3 Other methods for global orbit correction . . . . . . . . . 86
3.3.4 Local orbit correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
The path of the beam through an accelerator lattice may be called the orbit
or the trajectory. In circular accelerators, there exists a closed beam path,
which is called the orbit. In one-pass lattices, such as linacs or transport lines,
the beam path varies from shot to shot, depending on the launching angles
and positions. The beam path in one-pass systems is the trajectory, which is
often loosely referred to as the orbit.
The beam orbit or trajectory is important to the beam performance. Most
beam applications require precise positioning of the beam in order to be effective. For example, in collider experiments, the two colliding beams have
to overlap in space for collisions to happen. In synchrotron light sources, the
electron beam orbit has to be precisely controlled for the photon beam to
be focused on the sample. In a free electron laser (FEL), trajectory errors in
the undulators not only affect the photon beam positioning on the samples,
but also can severely reduce the FEL power. Orbit or trajectory errors may
cause a reduction of the effective aperture when the beam is driven toward the
vacuum chamber and cause beam losses. In circular accelerators, orbit errors
in nonlinear magnets (e.g., sextupoles) cause optics errors and linear coupling
and can impact the nonlinear beam dynamics performance. Typically, orbit
or trajectory control is a high priority in accelerator operation.
69
C H A P T E R 3
Orbit and trajectory
correction
CONTENTS
3.1
Accelerator components for orbit correction . . . . . . . . . . . . . . 70
3.1.1 Beam position monitors . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
3.1.2 Orbit correctors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
3.2
Beam-based alignment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
3.3
Orbit correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
3.3.1 Orbit correction with SVD . . . . . . . . . . . . . . . . . . . . . . . . . 78
3.3.2 Orbit correction with weights on BPMs . . . . . . . . . . 84
3.3.3 Other methods for global orbit correction . . . . . . . . . 86
3.3.4 Local orbit correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
The path of the beam through an accelerator lattice may be called the orbit
or the trajectory. In circular accelerators, there exists a closed beam path,
which is called the orbit. In one-pass lattices, such as linacs or transport lines,
the beam path varies from shot to shot, depending on the launching angles
and positions. The beam path in one-pass systems is the trajectory, which is
often loosely referred to as the orbit.
The beam orbit or trajectory is important to the beam performance. Most
beam applications require precise positioning of the beam in order to be effective. For example, in collider experiments, the two colliding beams have
to overlap in space for collisions to happen. In synchrotron light sources, the
electron beam orbit has to be precisely controlled for the photon beam to
be focused on the sample. In a free electron laser (FEL), trajectory errors in
the undulators not only affect the photon beam positioning on the samples,
but also can severely reduce the FEL power. Orbit or trajectory errors may
cause a reduction of the effective aperture when the beam is driven toward the
vacuum chamber and cause beam losses. In circular accelerators, orbit errors
in nonlinear magnets (e.g., sextupoles) cause optics errors and linear coupling
and can impact the nonlinear beam dynamics performance. Typically, orbit
or trajectory control is a high priority in accelerator operation.
69
C H A P T E R 3
Orbit and trajectory
correction
CONTENTS
3.1
Accelerator components for orbit correction . . . . . . . . . . . . . . 70
3.1.1 Beam position monitors . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
3.1.2 Orbit correctors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
3.2
Beam-based alignment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
3.3
Orbit correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
3.3.1 Orbit correction with SVD . . . . . . . . . . . . . . . . . . . . . . . . . 78
3.3.2 Orbit correction with weights on BPMs . . . . . . . . . . 84
3.3.3 Other methods for global orbit correction . . . . . . . . . 86
3.3.4 Local orbit correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
The path of the beam through an accelerator lattice may be called the orbit
or the trajectory. In circular accelerators, there exists a closed beam path,
which is called the orbit. In one-pass lattices, such as linacs or transport lines,
the beam path varies from shot to shot, depending on the launching angles
and positions. The beam path in one-pass systems is the trajectory, which is
often loosely referred to as the orbit.
The beam orbit or trajectory is important to the beam performance. Most
beam applications require precise positioning of the beam in order to be effective. For example, in collider experiments, the two colliding beams have
to overlap in space for collisions to happen. In synchrotron light sources, the
electron beam orbit has to be precisely controlled for the photon beam to
be focused on the sample. In a free electron laser (FEL), trajectory errors in
the undulators not only affect the photon beam positioning on the samples,
but also can severely reduce the FEL power. Orbit or trajectory errors may
cause a reduction of the effective aperture when the beam is driven toward the
vacuum chamber and cause beam losses. In circular accelerators, orbit errors
in nonlinear magnets (e.g., sextupoles) cause optics errors and linear coupling
and can impact the nonlinear beam dynamics performance. Typically, orbit
or trajectory control is a high priority in accelerator operation.
69