A modification of canonical variational transition state theory in which, for energies below the threshold energy, the position of the dividing surface is taken to be that of the microcanonical threshold energy.
12.
However, this simple model does not take into account so called neutron resonances, which strongly modify neutron cross section in energy range of 1 eV 10 keV, nor threshold energy of some nuclear reactions.
13.
The initial clinical experience led to further animal research using impedance and pacing threshold energy over a range of pulse voltages and pulse widths, using intramyocardial electrodes of 10, 20 & 50 square millimeters surface area.
14.
In the extreme case, the cross section can be, at low energies, either zero ( the energy for which the cross section becomes significant is called threshold energy ) or much larger than at high energies.
15.
If the wave theory of light had been correct, the threshold energy could be overcome either by increasing amplitude or frequency since the power of a ( mechanical ) wave is dictated by both its amplitude and frequency.
16.
In most cases the pumping power required to achieve lasing threshold will be proportional to the left side of the equation, that is P _ \ text { threshold } \ propto 2g _ \ text { threshold } \, l . ( This analysis is equally applicable to considering the threshold energy instead of the threshold power.
