Variable parameters for global
How to create an initalfile
Declaration of the outputfile
Index

SIGNAL commands - declaration of the theory function(s)

    In this part of the initialfile the theory function(s) which should be fitted to the data are declared. The command for theory definition is:

SIGNAL      ,    ,    ,    ,  
!        pha, asy, frq, rel, pow/hop

while the slots have to be filled (in the obligarory order as shown in the line below) with the numbers of the parameters declared in the parameterlist (see The parameterlist). It is quite useful but not necessary to define the parameters in the parameterlist in a way that the slots can be filled with increasing numbers.

Comment: When you look at the outputfile as shown here, you'll find 5 more possible slots to be filled - they are specified by 5x[OMNI_TBL]. You have to fill these slots if you want to use 3-dimensional tables.

• single signal theory:  
  One line defines a single signal theory function.
• sum of theory functions:  
  Two or more signal lines define a theory function, which is the sum of the specified signals, if amplitudes are specified for each signal. Each line must have SIGNAL at the beginning.
            
  Example:

  SIGNAL    2 , 3  , 4  , 5  ,  
  SIGNAL    2 , 6  , 4  , -7 ,  
  !        pha, asy, frq, rel, pow/hop

  Here two signals with same phase and frequency but different asymmetries and relaxations are added. The first signal shows exponential, the second one gaussian damping.
• product of theory functions:  
  Two signal lines, where the first one has no (=zero) asymmetry and only the second one has a finite asymmetry, define a theory function which is a product of two functions (double relaxation)  . Each line must have a SIGNAL at the beginning.
              
  Example:

  SIGNAL    2 ,   , 4  , 5  ,  
  SIGNAL    2 , 3  , 4  , -6 ,  
  !        pha, asy, frq, rel, pow/hop

  Here an exponential (first line) and a gaussian damped (second line) signal are multiplied.

The specification of different functions is done by filling the slots in different ways. Here is a list of the available theory functions and the required filling of the slots:

pha asy frq rel pow/hop geometrie theory function

# #   #   # 0 TF Exponential damping  

# #   #   # # TF Power exponential damping  

# #   # -# 0 TF Gaussian damping  

# #   # -# # TF Abragam function  

0 #  0   # 0 ZF Exponential damping in zero field  

0 #  0   # # ZF Power exponential damping in zero field  

0 #  0   # -# ZF Power of time  

0 #  0   -# 0 ZF Static Gaussian-Kubo-Toyabe function in zero field  

0 # -# -# 0 LF Static Gaussian-Kubo-Toyabe function in longitudinal field (calls for table, see Kubo-Toyabe functions)  

0 #  0 -# # ZF Dynamical (Gaussian or Lorentzian) Kubo-Toyabe in ZF (calls for table, see Kubo-Toyabe functions)  

0 # -# -# # LF Dynamical Kubo-Toyabe in longitudinal field (calls for table, see Kubo-Toyabe functions,
frq = 13.55 MHz/kG,)  

Comment: Instead of 0 you can use a blanc.

• Variable parameters for global fit
• Redefinition of parameters
• Kubo-Toyabe functions