Radiofrequency pulse with a narrow frequency
spectral bandwidth (long, low-power pulse) to excite nuclei in a limited chemical shift range (see
selective excitation).
Source:
PAC, 2021, 93, 647. 'Glossary of methods and terms used in analytical spectroscopy (IUPAC Recommendations 2019)' on page 704 (https://doi.org/10.1515/pac-2019-0203)