Bright light is found to emit from photographer’s flashgun. This brightness is due to the presence of which one of the following noble gases?

The bright light emitted from a photographer’s flashgun is primarily due to the presence of Xenon gas. A flashgun, or flashtube, consists of a hermetically sealed glass tube filled with a noble gas, most commonly xenon [1]. When a high-voltage electrical current from a capacitor is discharged through the tube, the xenon gas ionizes, producing an instantaneous, high-intensity pulse of light [1]. Xenon is preferred because it produces a full-spectrum white light that closely resembles natural daylight, unlike neon which produces red light or mercury which produces bluer light. While other noble gases like argon and nitrogen are used in standard electric bulbs to prevent filament oxidation, xenon's unique atomic structure allows it to emit the intense, short-duration brightness required for photography [3].

Sources

1. [1] https://en.wikipedia.org/wiki/Flashtube
2. [3] Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 20: Earths Atmosphere > Nitrogen > p. 272