Page 95 - bukuneutron

This is kind of linear equation with axis Y = tanθ,

axis X = 1 and the slope m = ( λ θ ) ) with –tan θ
2dcosθ cos( 2 2

is a point on the Y axis when the value 1 = 0.
2dcosθ
Therefore, data for Y and X can be obtained from neu-

tron diffraction experiment of standard powder and fit

the plot and then get the value of wavelength from the

slope, m.

The profile of Bragg peaks for the [hkl] planes of
standard Si powder obtained from experiment is given
in Figure 4.4. The 2θ angle for each Bragg peak is
given at center obtained from fitting using Gaussian
equation. Using the angle 2θ obtained from fitting to
get data for axis X and Y based on the equation derived
above.

Graph in Figure 4.3 given the linear curve for cal-
culation of the slope m for determination of neutron
wavelength. For ∆θ = 2atas(C)x180/pi = 0.062929,
the wavelength of neutron obtained from the measure-
ment is given in Table 4.2. Similar approach can be
used to determine the wavelength of neutron instru-
ment if single cyrtal monochromator is used. However
different in the [hkl] planes and 2theta values.

82