at.physics.ring_parameters#

Functions

`radiation_parameters`(ring[, dp, params])	Compute ring parameters from the radiation integrals
`envelope_parameters`(ring[, params, orbit, ...])	Compute ring parameters from ohmi_envelope

Classes

Class for pretty printing the ring properties

class RingParameters(**kwargs)[source]#

Class for pretty printing the ring properties

envelope_parameters(ring, params=None, orbit=None, keep_lattice=False)[source]#

Compute ring parameters from ohmi_envelope

Parameters:

ring (Lattice) – Lattice description.
params (RingParameters | None) – RingParameters object to be updated. Default: create a new one
orbit (ndarray | None) – Avoids looking for the closed orbit if it is already known ((6,) array)
keep_lattice (bool) – Assume no lattice change since the previous tracking.

Returns:

params – RingParameters object.

params is a RingParameters object with the following attributes:

tunes6	(3,) fractional (H, V, Long.) tunes (6D motion)
emittances	(3,) Mode emittances
J	(3,) Damping partition numbers
Tau	(3,) Damping times [s]
sigma_e	Energy spread
sigma_l	Bunch length [m]
voltage	Total accelerating voltage [V]
phi_s	Synchrotron phase [rad]
f_s	Synchrotron frequency [Hz]

radiation_parameters(ring, dp=None, params=None, **kwargs)[source]#

Compute ring parameters from the radiation integrals

Valid for uncoupled lattices with no RF cavity or radiating element.

Parameters:

ring (Lattice) – Lattice description.
dp (float | None) – Momentum deviation.
params (RingParameters | None) – RingParameters object to be updated. Default: create a new one

Keyword Arguments:

dct (float) – Path lengthening. If specified, dp is ignored and the off-momentum is deduced from the path lengthening.
method (Callable) –
Method for linear optics:

linopt2: no longitudinal motion, no H/V coupling,

linopt6 (default): with or without longitudinal motion, normal mode analysis
orbit (Orbit) – Avoids looking for the closed orbit if is already known ((6,) array)
XYStep (float) – Step size. Default: DConstant.XYStep
DPStep (float) – Momentum step size. Default: DConstant.DPStep

Returns:

params – RingParameters object.

params is a RingParameters object with the following attributes:

tunes	(3,) fractional (H, V, Long.) tunes
fulltunes	(3,) full tunes
chromaticities	(2,) H, V Chromaticities
alphac	Momentum compaction factor
etac	Frequency slip factor
E0	Energy [eV]
U0	Energy loss / turn [eV]
i1	Radiation integrals - \(I_1 \quad [m]\)
i2	\(I_2 \quad [m^{-1}]\)
i3	\(I_3 \quad [m^{-2}]\)
i4	\(I_4 \quad [m^{-1}]\)
i5	\(I_5 \quad [m^{-1}]\)
emittances	(3,) Mode emittances
J	(3,) Damping partition numbers
Tau	(3,) Damping times [s]
sigma_e	Energy spread
sigma_l	Bunch length [m]
voltage	Total accelerating voltage [V]
phi_s	Synchrotron phase [rad]
f_s	Synchrotron frequency [Hz]