Dataset for "Optical absorption spectrum reveals gaseous chlorine in anti-resonant hollow core fibres"

We have observed unexpected spectral attenuation of ultraviolet light in freshly drawn hollow core optical fibres, which we measure through a short length of fibre using a bentham monochromator and a broadband laser driven light source (EQ-99X). When the fibre ends are left open to atmosphere, this loss feature dissipates over time. The loss matches the absorption spectrum of gaseous (molecular) chlorine and, given enough time, the transmission spectrum of the fibre recovers to that expected from the morphological structure of the fibre. This dataset contains the spectral data output from the optical fibre that was analyzed to show this.