Non-coherent intense source of ultraviolet, visible, and near-infrared radiation produced by an electrical discharge in a mixture of mercury vapour and xenon under high pressure.
Source:
PAC, 2007, 79, 293. 'Glossary of terms used in photochemistry, 3rd edition (IUPAC Recommendations 2006)' on page 369 (https://doi.org/10.1351/pac200779030293)