hadron (version 3.1.2)

subtract.excitedstates: Substract excited states.

Description

Excited states are subtracted from the given correlation function and matching matrixfit. The fit is usually done on late time slices when the thermal states have decayed so much that they can be neglected. On the early time slices there are contributions which cannot be explained with a single cosh (or sinh) function. These are exactly the contributions that we do not want.

Usage

subtract.excitedstates(cf, mfit, from.samples = FALSE)

Arguments

cf

Correlation function of class cf.

mfit

Fit result of class matrixfit.

from.samples

Whether to use existing bootstrap samples. If set to TRUE, the same operation will be applied to the bootstrap samples. Otherwise the result will not contain bootstrap samples, even if the input correlation function did.

Value

A correlation function of class cf which is computed from the old correlation function $C(t)$ as $M(t)+C(t)-\overline{C}(t)$, where $M(t)$ is the fit model and $\overline{C}(t)$ denotes the average over the (bootstrap) samples. Only time slices earlier than the fit are altered.

Details

The correlation function is altered on the time slices which are earlier than the start of the fit interval. The correlator is replaced by the model function (cosh or sinh or exp) extrapolated until the first time slice. The deviations of the (bootstrap) samples from the mean value are kept.