diff --git a/collective_effects/__init__.py b/collective_effects/__init__.py
index 50123bb7163425ebe74e564e981faa67474b4e2d..bdea55f7291697a9d610b142d34d1f23d82ade5b 100644
--- a/collective_effects/__init__.py
+++ b/collective_effects/__init__.py
@@ -7,7 +7,7 @@ Created on Tue Jan 14 12:25:30 2020
from mbtrack2.collective_effects.instabilities import mbi_threshold, cbi_threshold
from mbtrack2.collective_effects.resistive_wall import skin_depth, CircularResistiveWall
-from mbtrack2.collective_effects.resonator import Resonator
+from mbtrack2.collective_effects.resonator import Resonator, PureInductive, PureResistive
from mbtrack2.collective_effects.tapers import StupakovRectangularTaper, StupakovCircularTaper
from mbtrack2.collective_effects.wakefield import ComplexData, Impedance, WakeFunction, WakeField
from mbtrack2.collective_effects.utilities import read_CST, read_IW2D, spectral_density
diff --git a/collective_effects/resonator.py b/collective_effects/resonator.py
index c6a083d86542067dd1e8916ab7bcfb3ee6592d79..f11948ee3abe5b923d4d5f66bbcf2e483b64df09 100644
--- a/collective_effects/resonator.py
+++ b/collective_effects/resonator.py
@@ -12,7 +12,7 @@ from mbtrack2.collective_effects.wakefield import (WakeField, Impedance,
WakeFunction)
class Resonator(WakeField):
- def __init__(self, Rs, fr, Q, plane, n_wake=1e4, n_imp=1e4, imp_freq_lim=50e9):
+ def __init__(self, Rs, fr, Q, plane, n_wake=1e6, n_imp=1e6, imp_freq_lim=100e9):
"""
Resonator model WakeField element which computes the impedance and the
wake function in both longitudinal and transverse case.
@@ -28,11 +28,11 @@ class Resonator(WakeField):
plane : str
Plane on which the resonator is used: "long", "x" or "y".
n_wake : int or float, optional
- Number of points used in the wake function. The default is 1e4.
+ Number of points used in the wake function.
n_imp : int or float, optional
- Number of points used in the impedance. The default is 1e4.
+ Number of points used in the impedance.
imp_freq_lim : float, optional
- Maximum frequency used in the impedance. The default is 50e9.
+ Maximum frequency used in the impedance.
References
----------
@@ -117,4 +117,76 @@ class Resonator(WakeField):
else:
return (self.wr * self.Rs / self.Q_p *
np.exp(-1 * t * self.wr / 2 / self.Q_p) *
- np.sinh(self.wr_p * t) )
\ No newline at end of file
+ np.sinh(self.wr_p * t) )
+
+class PureInductive(WakeField):
+ """
+ Pure inductive Wakefield element which computes associated longitudinal
+ impedance and wake function.
+
+ Parameters
+ ----------
+ L : float
+ Inductance value in [Ohm/Hz].
+ n_wake : int or float, optional
+ Number of points used in the wake function.
+ n_imp : int or float, optional
+ Number of points used in the impedance.
+ imp_freq_lim : float, optional
+ Maximum frequency used in the impedance.
+ nout, trim : see Impedance.to_wakefunction
+ """
+ def __init__(self, L, n_wake=1e6, n_imp=1e6, imp_freq_lim=1e11, nout=None,
+ trim=False):
+ self.L = L
+ self.n_wake = int(n_wake)
+ self.n_imp = int(n_imp)
+ self.imp_freq_lim = imp_freq_lim
+
+ freq = np.linspace(start=1, stop=self.imp_freq_lim, num=self.n_imp)
+ imp = Impedance(variable=freq,
+ function=self.long_impedance(freq),
+ impedance_type="long")
+ super().append_to_model(imp)
+
+ wf = imp.to_wakefunction(nout=nout, trim=trim)
+ super().append_to_model(wf)
+
+ def long_impedance(self, f):
+ return 1j*self.L*f
+
+class PureResistive(WakeField):
+ """
+ Pure resistive Wakefield element which computes associated longitudinal
+ impedance and wake function.
+
+ Parameters
+ ----------
+ R : float
+ Resistance value in [Ohm].
+ n_wake : int or float, optional
+ Number of points used in the wake function.
+ n_imp : int or float, optional
+ Number of points used in the impedance.
+ imp_freq_lim : float, optional
+ Maximum frequency used in the impedance.
+ nout, trim : see Impedance.to_wakefunction
+ """
+ def __init__(self, R, n_wake=1e6, n_imp=1e6, imp_freq_lim=1e11, nout=None,
+ trim=False):
+ self.R = R
+ self.n_wake = int(n_wake)
+ self.n_imp = int(n_imp)
+ self.imp_freq_lim = imp_freq_lim
+
+ freq = np.linspace(start=1, stop=self.imp_freq_lim, num=self.n_imp)
+ imp = Impedance(variable=freq,
+ function=self.long_impedance(freq),
+ impedance_type="long")
+ super().append_to_model(imp)
+
+ wf = imp.to_wakefunction(nout=nout, trim=trim)
+ super().append_to_model(wf)
+
+ def long_impedance(self, f):
+ return self.R
\ No newline at end of file
diff --git a/collective_effects/wakefield.py b/collective_effects/wakefield.py
index 01fa913dfcaa94a85d881bfb0557f464764782fa..ee372cb5f06023070b4671336860de968e886eab 100644
--- a/collective_effects/wakefield.py
+++ b/collective_effects/wakefield.py
@@ -569,13 +569,14 @@ class Impedance(ComplexData):
def to_wakefunction(self, nout=None, trim=False):
"""
Return a WakeFunction object from the impedance data.
+ The impedance data is assumed to be sampled equally.
Parameters
----------
- nout : int, optional
+ nout : int or float, optional
Length of the transformed axis of the output. If None, it is taken
to be 2*(n-1) where n is the length of the input. If nout > n, the
- input is padded with zeros. If nout < n, the inpu it cropped.
+ input is padded with zeros. If nout < n, the input it cropped.
Note that, for any nout value, nout//2+1 input points are required.
trim : bool or float, optional
If True, the pseudo wake function is trimmed at time=0 and is forced
@@ -597,6 +598,8 @@ class Impedance(ComplexData):
if nout is None:
nout = len(Z)
+ else:
+ nout = int(nout)
time_array = sc.fft.fftfreq(nout, sampling)
Wlong_raw = sc.fft.irfft(np.array(Z), n=nout, axis=0) * nout * fs