echo time

symbol: $T_{\rm{E}}$
initialism: TE
https://doi.org/10.1351/goldbook.08337
In nuclear magnetic resonance spectroscopy, time interval between the middle of the first radiofrequency pulse and the peak of the spin echo.
Source:
PAC, 2021, 93, 647. 'Glossary of methods and terms used in analytical spectroscopy (IUPAC Recommendations 2019)' on page 687 (https://doi.org/10.1515/pac-2019-0203)