Chapter 32 - Nuclear Physics and Nuclear Radiation - Problems and Conceptual Exercises - Page 1152: 15

alpha ($\alpha$) and beta ($\beta$)

We know that alpha and beta particle decay results in a new element as $Z_{\alpha}=Z-2$ and $Z_{\beta}=Z+1$. This shows that the atomic nucleus changes. On the other hand, gamma decay results into energy release and there is no change in atomic number.