Definition: In this task you will be given a text passage from a trivia quiz. You should choose the category this question belongs to from these categories: History, Science, Social Science, Fine Arts, Literature. You can only choose one category, so if in doubt, please choose the closest match.
Input: Gravitational redshift was measured by Pound, Rebka, and Snider in Harvard's Jefferson Tower using this technique to detect a frequency shift of order one part in ten to the 14th. It can be used for precise studies of the Zeeman effect in nuclei. Iron 57 and tin 119 are two of the isotopes used in this type of spectroscopy due to narrow linewidths in their transitions. Before this technique, the large size of Doppler shifts relative to transition widths made nuclear spectroscopy problematic. It was discovered by its namesake when he was a graduate student at the Munich University of Technology. FTP, what is this effect in which a crystal lattice reduces recoil energy
Output:
Science