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Herwig  7.2.1
Interfaces defined for the Herwig::ShowerAlphaQCD class.
Brief class description:
This (concrete) class describes the QCD alpha running.
See also Herwig::ShowerAlphaQCD

Name: QuarkMasses
Type: Varying size vector of parameters

Description:
The quark masses to be used instead of the masses set in the particle data.
Default value: 0
Minimum value: 0

Name: InputScale
Type: Parameter

Description:
An optional input scale. MZ will be used if not set.
Default value: 91.1876
Minimum value: 0

Name: ThresholdOption
Type: Switch

Description:
Whether to use the consistuent or normal masses for the thresholds
Registered options:
0(Constituent)
Use the constitent masses.
1(Current)
Use the current masses
Default value: 1

Name: MaximumIterations
Type: Integer parameter

Description:
The maximum number of iterations for the Newton-Raphson method to converge.
Default value: 100
Minimum value: 10
Maximum value: 1000

Name: Tolerance
Type: Parameter

Description:
The tolerance for discontinuities in alphaS at thresholds.
Default value: 1e-10
Minimum value: 1e-20
Maximum value: 0.0001

Name: AlphaIn
Type: Parameter

Description:
The input value of the strong coupling at the chosen InputScale (default: MZ)
Default value: 0.118
Minimum value: 0.1
Maximum value: 0.2

Name: NumberOfLoops
Type: Integer parameter

Description:
The number of loops to use in the alpha_S calculation
Default value: 3
Minimum value: 1
Maximum value: 3

Name: AlphaMaxNP
Type: Parameter

Description:
Max value of alpha in NP region, only relevant if NPAlphaS = 5,6
Default value: 1
Minimum value: 0
Maximum value: 100

Name: Qmin
Type: Unlimited Parameter

Description:
Q < Qmin is treated with NP parametrization as of (unit [GeV]), if negative it is solved for at initialisation such that alpha_S(Qmin)=AlphaMaxNP
Default value: 0.630882

Name: NPAlphaS
Type: Switch

Description:
Behaviour of AlphaS in the NP region
Registered options:
1(Zero)
zero below Q_min
2(Const)
const as(qmin) below Q_min
3(Linear)
growing linearly below Q_min
4(Quadratic)
growing quadratically below Q_min
5(Exx1)
quadratic from AlphaMaxNP down to as(Q_min)
6(Exx2)
const = AlphaMaxNP below Q_min
Default value: 1

Name: check
Type: Command

Description:
check

Name: Value
Type: Command

Description:


Name: AlphaMZ
Type: Deleted

Description:
Renamed to AlphaIn.

Name: InputOption
Type: Deleted

Description:
The old default (1) is now the only choice

There may be interfaces inherited from the Herwig::ShowerAlpha class.