The inside of the North Bore service tunnel.Credit: Richard Newman

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Driving through the Huguenot tunnel near Cape Town in 2013, nuclear physicist, Shaun Wyngaardt, had the idea of building a deep underground physics laboratory next to the existing tunnel. Under 800 metres of rock forming the Du Toitskloof mountain, it would not be the world’s deepest or biggest underground lab, but would offer physics researchers in southern Africa the chance to participate in the global search for dark matter.

More than a decade later, the Paarl Africa Underground Laboratory (PAUL) project has been launched. It will be the first dedicated and permanent underground laboratory in Africa, and only the second one in the southern hemisphere after Australia’s Stawell Underground Physics Laboratory. Currently a dozen such underground laboratories in Asia, Europe, and North America are used to observe and study the rare interactions between neutrinos and still unknown dark matter particles with ordinary matter. Neutrinos – also called ‘ghost’ particles – are extremely light sub-atomic particles that do not emit, absorb, or reflect light, and are therefore extremely difficult to observe.

Richard Newman from Stellenbosch University’s Department of Physics and Faïrouz Malek, director of research at France’s National Institute for Nuclear and Particle Physics. Credit: Wiida Fourie-Basson
Wyngaardt, now head of the Department of Physics at Stellenbosch University, had to convince fellow physicists of the idea of the tunnel rather than utilising one of South Africa’s very deep gold mines. It was in 1965 in one of these mines, three kilometres deep, that physicists, Friedel Sellschop and Frederick Reines, made the world’s first observation of a naturally occurring cosmic neutrino.

The new laboratory has the support of Faïrouz Malek, a high energy physics researcher at CERN’s Large Hadron Collider and director of research at the National Institute for Nuclear and Particle Physics at France’s National Centre for Scientific Research (CNRS).

She contends that there are signals from the Universe that one can detect by performing tabletop research — smaller and less costly experiments, not located in space or at large observatories on Earth.

“The size of the experiment does not say anything about its scientific potential,” agrees Jochen Schieck, director of the Institute for High Energy Physics at the Austrian Academy of Science. “Some questions can only be addressed with large experiments, others with tabletop setups. At the end you have to bring the pieces from all the experiments together to unlock the puzzles from the universe.”

According to Malek, physicists in Africa need to up their game and improve cooperation with the world community of scientists, engineers, technicians, funding agencies and policymakers.

In 2019, Malek and, physicist Ketevi Assamagan, co-founded the African Strategy for Fundamental and Applied Physics (ASFAP). The main objective is to establish a scientific culture of international cooperation, between African countries, and with the international community.

The magnificent Du Toits Kloof mountains in the Western Cape will become the bedrock shielding the planned Paarl Africa Underground Laboratory (PAUL) from cosmic radiation.Credit: Wiida Fourie-Basson
In the same year, she wrote a letter of protest deploring Africa’s absence in major strategic discussions on research and strategic vision in particle physics. Co-signed by Assamagan and published in the African Physics Newsletter, they emphasised the benefits that would come from African participation in these discussions. Malek jumped at the opportunity to engage with Wyngaardt and fellow physicist, Richard Newman, at Stellenbosch University when she learned about their efforts to establish an underground neutrino facility in the Huguenot tunnel.

By 2022 ASFAP’s plan started bearing fruit. South Africa’s Department of Science and Innovation (DSI) provided seed funding for independent scientific and engineering feasibility studies, with an additional support from Stellenbosch University.

Stakeholders are now awaiting the results of the engineering feasibility study, before bringing all players around the table, including South Africa’s Department of Transport and the South African National Road Agency Limited (SANRAL).

SANRAL is planning to upgrade a service tunnel at the north of the Huguenot tunnel over the next five to ten years to lessen the impact of high traffic volumes and the underground laboratory could be established as part of the process.