There is just the likelihood function of the normal distribution with a replacement rule.
I like to work with greeks in Mathematica :), so if you copy the LaTeX code below in the online editor: http://www.codecogs.com/latex/eqneditor.php, you will get the picture.
\left(2 \pi \sigma ^2\right)^{-\frac{n}{2}} \exp \left(-\frac{\sum _{i=1}^n \left(x_i-\theta \right){}^2}{2 \sigma ^2}\right)\text{/.}\, \sigma ^2\to \kappa
