`MoessbauerIsotope`

class nexus.MoessbauerIsotope(isotope='none', element='', mass=0.0, energy=0.0, lifetime=0.0, internal_conversion=0.0, multipolarity=0, mixing_ratio_E2M1=0.0, spin_ground=0.0, spin_excited=0.0, gfactor_ground=0.0, gfactor_excited=0.0, quadrupole_ground=0.0, quadrupole_excited=0.0, interference_term=0.0, natural_abundance=0.0)

Constructor for the MoessbauerIsotope class.

Parameters:

isotope (string) – User identifier. Should be given in the format “mass number-element”, e.g. “57-Fe”.
element (string) – Element symbol, e.g. “Fe” for iron.
mass (float) – Isotope mass in unified atomic mass unit / Daltons (u).
energy (float) – Transition energy (eV).
lifetime (float) –
Life time (seconds).

Changed in version 1.2.0: version < 1.2.0 in nanoseconds, since 1.2.0 in seconds.
internal_conversion (float or Var) –
Internal conversion factor \(\alpha\).

Changed in version 1.2.0: Var input possible now.
multipolarity (Multipolarity) –
Multipolarity of the transition, one of the following options
- nexus.Multipolarity_E1 (0)
- nexus.Multipolarity_M1 (1)
- nexus.Multipolarity_E2 (2)
- nexus.Multipolarity_M1E2 (3)
- nexus.Multipolarity_M2 (4)
Changed in version 1.0.3: Multipolarity M2 added.
mixing_ratio_E2M1 (float or Var) –
The mixing ratio \(\delta\) of the E2 and M1 transitions. Note, that the definition of the sign is not consistent in literature. The sign convention here is such that for 193-Ir, the mixing coefficient is positive, although it is often found negative in literature. See [Sturhahn].

”The E2/M1 mixing parameter \(\delta\) is defined as the ratio of the reduced E2 and M1 matrix elements. Thus \(\delta^2\) gives the relative intensities of E2 and M1 type radiation. The sign of \(\delta\), which describes the relative phase of the E2 and M1 waves, is a matter of definition and therefore inevitably a source of confusion.” [Wagner].

Changed in version 1.2.0: Var input possible now.
spin_ground (float) – Spin of the ground state \(I_g\).
spin_excited (float) – Spin of the excited state \(I_e\).
gfactor_ground (float Var) –
g-factor of the ground state \(g_g\).

Changed in version 1.2.0: Var input possible now.
gfactor_excited (float or Var) –
g-factor of the excited state \(g_e\).

Changed in version 1.2.0: Var input possible now.
quadrupole_ground (float or Var) –
Quadrupole moment of the ground state (barn).

Changed in version 1.2.0: Var input possible now.
quadrupole_excited (float or Var) –
Quadrupole moment of the excited state (barn).

Changed in version 1.2.0: Var input possible now.
interference_term (float or Var) –
Interference term of the nuclear and electronic currents (\(\beta\)).

Changed in version 1.2.0: Var input possible now.
natural_abundance (float) –
Natural abundance of the isotope.

Added in version 2.0.0.

isotope

User identifier. Should be given in the format “mass number-element”, e.g. “57-Fe”.

Type:: string

element

Element symbol, e.g. “Fe” for iron.

Type:: string

mass

Isotope mass in unified atomic mass unit / Daltons (u).

Type:: float

energy

Transition energy (eV).

Type:: float

lifetime

Lifetime of the state (seconds).

Type:: float

internal_conversion

Internal conversion factor \(\alpha\).

Changed in version 1.2.0: version < 1.2.0 float type, now Var.

Type:: Var

multipolarity

Multipolarity of the transition, one of the following options

nexus.Multipolarity_E1 (0)
nexus.Multipolarity_M1 (1)
nexus.Multipolarity_E2 (2)
nexus.Multipolarity_M1E2 (3)
nexus.Multipolarity_M2 (4)

Changed in version 1.0.3: Multipolarity M2 added.

Type:: Multipolarity

L

Photon angular momentum. For mixed multipolarity M1E2, photon angular momentum of M1.

L=1 for E1 and M1 transitions
L=2 for E2 and “M2” transitions

Type:: int

lambda1

Scattering type (electronic or magnetic). For mixed multipolarity M1E2, scattering type of M1.

\(\lambda = 1\) for electronic E1 and E2 transition.
\(\lambda = 0\) for magnetic M1 and M2 transition.

Type:: int

L2

For mixed multipolarity M1E2, photon angular momentum of E2, L=2.

Type:: int

lambda2

For mixed multipolarity M1E2, scattering type of E2, \(\lambda = 0\).

Type:: int

mixing_ratio_E2M1

The mixing ratio \(\delta\) of the E2 and M1 transitions. Note, that the definition of the sign is not consistent in literature. The sign convention here is such that for 193-Ir, the mixing coefficient is positive, although it is often found negative in literature. See [Sturhahn].

“The E2/M1 mixing parameter \(\delta\) is defined as the ratio of the reduced E2 and M1 matrix elements. Thus \(\delta^2\) gives the relative intensities of E2 and M1 type radiation. The sign of \(\delta\), which describes the relative phase of the E2 and M1 waves, is a matter of definition and therefore inevitably a source of confusion.” [Wagner].

Changed in version 1.2.0: version < 1.2.0 float type, now Var.

Type:: Var

spin_ground

Spin of the ground state \(I_g\).

Type:: float

spin_excited

Spin of the excited state \(I_e\).

Type:: float

gfactor_ground

g-factor of the ground state \(g_g\).

Changed in version 1.2.0: version < 1.2.0 float type, now Var.

Type:: Var

gfactor_excited

g-factor of the excited state \(g_e\).

Changed in version 1.2.0: version < 1.2.0 float type, now Var.

Type:: Var

quadrupole_ground

Quadrupole moment of the ground state (kbarn).

Changed in version 1.2.0: version < 1.2.0 float type, now Var.

Type:: Var

quadrupole_excited

Quadrupole moment of the excited state (kbarn).

Changed in version 1.2.0: version < 1.2.0 float type , now Var.

Type:: Var

interference_term

Interference term of the nuclear and electronic currents (\(\beta\)).

Changed in version 1.2.0: version < 1.2.0 float type , now Var.

Type:: Var

atomic_number

Atomic (proton) number.

Type:: int

wavelength

Wavelength of the transition energy (meter).

Type:: float

kvector

k-vector of the transition energy (1/meter).

Type:: float

half_lifetime

Half lifetime of the state (seconds).

Added in version 1.0.3.

Type:: float

gamma

Transition linewidth (eV), \(\Gamma = \Gamma_{\gamma} + \Gamma_e\).

Type:: float

gamma_photon

Partial transition linewidth by gamma emission (eV).

Added in version 1.0.3.

Type:: float

gamma_electron

Partial transition linewidth by internal conversion (eV).

Added in version 1.0.3.

Type:: float

quality_factor

Quality factor \(E/\Gamma\) of the transition.

Added in version 1.0.3.

Type:: float

nuclear_cross_section

Nuclear cross section (kbarn).

Type:: float

magnetic_moment_ground

Magnetic moment of the ground state (eV/T). It is given by \(\mu_g = g_g \mu_N I_g\), where \(I_g\) is given in units of \(\hbar\).

Type:: float

magnetic_moment_excited

Magnetic moment of the excited state (eV/T). It is given by \(\mu_e = g_e \mu_N I_e\), where \(I_e\) is given in units of \(\hbar\).

Type:: float

natural_abundance

Natural abundance of the isotope.

Added in version 2.0.0.

Type:: float

Copy(): Copies the MoessbauerIsotope.

Define a Moessbauer isotope. Predefined Moessbauer Isotopes can be found in the Material library Moessbauer.

Fe57 = nx.moessbauerIsotope(
  isotope = "57-Fe",
  element = "Fe",
  mass = 56.9353933,

  energy = 14412.497,
  lifetime = 141.11, # input here in nanoseconds, is converted to seconds during initialization

  internal_conversion = 8.21,
  multipolarity = "M1",
  mixing_ratio_E2M1 = 0,

  spin_ground = 1/2,
  spin_excited = 3/2,

  gfactor_ground = 0.18121,
  gfactor_excited = -0.10348,

  quadrupole_ground = 0,
  quadrupole_excited = 0.187
)

print(Fe57.wavelength)

copy_of_isotope = Fe57.Copy()

MoessbauerIsotope

`MoessbauerIsotope`