at.collective.beam_loading#

Functions

`add_beamloading`(ring, qfactor, rshunt[, ...])	Function to add beam loading to a cavity element, the cavity element is changed to a beam loading element that combines the energy kick from both the cavity and the resonator
`remove_beamloading`(ring[, cavpts, copy])	Function to remove beam loading from a cavity element, the beam loading element is changed to a beam loading element that combines the energy kick from both the cavity and the resonator

Classes

`BLMode`(value)	An enumeration.
`BeamLoadingElement`(family_name, length, ...)	Class to generate a beamloading element, inherits from Element additional argument are ring, cavity, qfactor, rshunt

class BLMode(value)[source]#

Bases: IntEnum

An enumeration.

PHASOR = 2#

WAKE = 1#

class BeamLoadingElement(family_name, length, voltage, frequency, ring, qfactor, rshunt, mode=BLMode.PHASOR, **kwargs)[source]#

Bases: RFCavity, Collective

Class to generate a beamloading element, inherits from Element additional argument are ring, cavity, qfactor, rshunt

Parameters:

ring (Lattice) – Lattice object
length (float) – Length of the cavity
voltage (float) – Cavity voltage [V]
frequency (float) – Cavity frequency [Hz]
qfactor (float) – Q factor
rshunt (float) – Shunt impedance, [\(\Omega\)]

Keyword Arguments:

Nslice (int) – Number of slices per bunch. Default: 101
Nturns (int) – Number of turn for the wake field. Default: 1
ZCuts – Limits for fixed slicing, default is adaptive
NormFact (float) – Normalization factor
mode (BLMode) – method for beam loading calculation BLMode.PHASOR (default) uses the phasor method, BLMode.WAKE uses the wake function. For high Q resonator, the phasor method should be used

Returns:

bl_elem (Element) – beam loading element

static build_from_cav(cav, ring, qfactor, rshunt, mode=BLMode.PHASOR, **kwargs)[source]#

Function to build the BeamLoadingElement from a cavity the FamName, Length, Voltage, Frequency and HarmNumber are taken from the cavity element

Parameters:

ring (Sequence) – Lattice object
qfactor (float) – Q factor
rshunt (float) – Shunt impedance, [\(\Omega\)]

Keyword Arguments:

Nslice (int) – Number of slices per bunch. Default: 101
Nturns (int) – Number of turn for the wake field. Default: 1
ZCuts – Limits for fixed slicing, default is adaptive
NormFact (float) – Normalization factor
mode (BLMode) – method for beam loading calculation BLMode.PHASOR (default) uses the phasor method, BLMode.WAKE uses the wake function. For high Q resonator, the phasor method should be used

Returns:

bl_elem (Element) – beam loading element

clear_history(ring=None)[source]#

is_compatible(other)[source]#: Checks if another Element can be merged

property ResFrequency#: Resonator frequency

property Vbeam#: Beam phasor (amplitude, phase)

property Vbunch#: Bunch phasor (amplitude, phase)

property Vcav#: Cavity phasor (amplitude, phase)

property Vgen#: Generator phasor (amplitude, phase)

default_pass = {False: 'DriftPass', True: 'BeamLoadingCavityPass'}#

add_beamloading(ring, qfactor, rshunt, cavpts=None, copy=False, **kwargs)[source]#

Function to add beam loading to a cavity element, the cavity element is changed to a beam loading element that combines the energy kick from both the cavity and the resonator

Parameters:

ring (Lattice) – Lattice object
qfactor (Union[float, Sequence[float]]) – Q factor. Scalar or array of float are accepted
rshunt (Union[float, Sequence[float]]) – Shunt impedance, [\(\Omega\)] for longitudinal Scalar or array of float are accepted

Keyword Arguments:

cavpts (Refpts) – refpts of the cavity. If None (default) apply to all cavity in the ring
Nslice (int) – Number of slices per bunch. Default: 101
Nturns (int) – Number of turn for the wake field. Default: 1
ZCuts – Limits for fixed slicing, default is adaptive
NormFact (float) – Normalization factor
mode (BLMode) – method for beam loading calculation BLMode.PHASOR (default) uses the phasor method, BLMode.WAKE uses the wake function. For high Q resonator, the phasor method should be used
copy – If True, returns a shallow copy of ring with new beam loading elements. Otherwise, modify ring in-place

remove_beamloading(ring, cavpts=None, copy=False)[source]#

Function to remove beam loading from a cavity element, the beam loading element is changed to a beam loading element that combines the energy kick from both the cavity and the resonator

Parameters:

ring – Lattice object

Keyword Arguments:

cavpts (Refpts) – refpts of the beam loading Elements. If None (default) apply to all elements
copy – If True, returns a shallow copy of ring with new cavity elements. Otherwise, modify ring in-place