The wild-looking HiPER (pronounced "hyper") is shorthand for a high-power pulsed W-band electron paramagnetic resonance (EPR) instrument. Essentially, it is a 9-tesla High-Performance electron resonance magnet used to search for free electrons in a material.
Known as the “witches hat” machine because of the 29 black, hat-sized cones that cover parts of it, this unique magnet has these strange cones to absorb pulses of radiation. Essentially, the cones are the scientific equivalent of soundproof insulation in a music studio: They absorb echoes from microwaves that would otherwise skew the test data. EPR instruments detect the presence of unpaired (or free) electrons in a material. While free electrons are often short lived, they play critical roles in many processes, including photosynthesis and oxidation.
The "high-power" part refers to the instrument's recently upgraded 1-kilowatt amplifier. Along with other revolutionary design innovations, it makes possible the machine's game-changing sensitivity.
Depending on the technique used with the instrument, this sensitivity is orders of magnitude greater than what was previously available to scientists. This means scientists can run experiments on a material even if they have a just a teeny, tiny bit of it. This capability is extremely significant in structural biology (among other research areas), when scientists might have just a smidgeon of the protein they want to characterize.