high-pressure mercury lamp (arc)

https://doi.org/10.1351/goldbook.H02825
Radiation source containing mercury at a pressure of ca. \(8\ \text{MPa}\) (ca. \(80\ \text{bar}\)) or higher which emits lines over a background continuum between about \(200\) and \(1400\ \text{nm}\).
See:
lamp
Source:
PAC, 1996, 68, 2223. (Glossary of terms used in photochemistry (IUPAC Recommendations 1996)) on page 2246 [Terms] [Paper]