First line of the abstract:

>We present the first experimental evidence, supported by theory and simulation, of spatiotemporal optical vortices (STOVs).

The experimental setup is diagrammed and explained in part III.A of the paper:

>In order to experimentally confirm the existence of STOVs, we image the spatiospectral phase and intensity profiles of femtosecond laser pulses midflight during their precollapse and postcollapse evolution in air.

Appendix A gives the experimental setup in enough detail for it to be reproduced in a lab with the correct equipment.