(Published - 18 February 2020}

Ntombi Yvonne Kheswa was born and raised on the dusty streets of Tembisa, a township on the East Rand (Ekurhuleni) in Gauteng Province whose name means “promise” or “hope”. She’s certainly lived up to that promise, earning a PhD in Physics from the University of the Western Cape and developing new beams of exotic particles at iThemba Laboratory for Accelerator Based Sciences (iThemba LABS) - bringing hope that a new generation of researchers can change our understanding of the universe.

“At iThemba LABS, the core business is to provide accelerated beams that are directed to a target material or sample to conduct various types of research or characterise the material species, i.e. target material + particle beam > product + other particles,” Kheswa explains. “These charged particle beams are initially prepared in a dedicated ion source before they can be accelerated to the target material.”

The main goal of Dr Kheswa’s study, entitled Synthesis of the metallocenes for the production of exotic high energy ion beams, was developing metallocenes for the production of xotic beams of nickel isotopes.

The methods advanced in this study will allow the production of exotic beams which are currently not available at iThemba LABS, leading to major breakthroughs in nuclear physics done here in South Africa.

“Her work is proof of principle that we can now study exotic stable nuclei such as 62Ni, which was accelerated for the first time ever here at iThemba LABS in South Africa,” says Prof Nico Orce of UWC’s Department of Physics and Astronomy. “It opens new possibilities for high-impact science and for exciting student projects to investigate the frontiers of nuclear physics through novel nuclear reactions, that thanks to Dr Kheswa and colleagues at UWC and iThemba LABS, can now be performed only in South Africa.”

It was a project nearly a decade in the making, Prof Orce notes.

“The experiment was first proposed in September 2011,” he recalls. “But it just couldn’t be done in South Africa at the time. The beams were not here; they were limited - and we needed to develop the technology to produce new science. We needed a dedicated PhD student capable of working on both the physics and the chemistry - someone with the patience and ability to do the job. We needed Ntombi!”

She’s quick to note that it’s not just her achievement, though.

“Good things in life don’t just come from talent or hard work,” she says. “They also require patience and team effort - and this study involved the collaboration and support of a variety of people, interactions, contributions and discussions with the Ion Source specialists from iThemba LABS (Rainer Thomae and Joele Mira among others), and the organometallic specialists from UWC Chemistry Department (Salam Titinchi and Hanna Abbo), and nuclear physics scientists from both UWC Physics Department and iThemba LABS Subatomic Physics - none of this would have been possible without them.”

A Long Walk To Scientific Freedom

Kheswa’s own journey wasn’t easy.

She moved to Durban, KwaZulu-Natal, to complete high school, and then, finding herself fascinated with the complexities of chemistry, completed her undergraduate education in chemistry at Durban University of Technology. The family relocated to the Western Cape when she was offered a job opportunity by iThemba Laboratory for Accelerator Based Sciences (iThemba LABS) in Somerset West, the largest national nuclear science facility on the continent.

“As a target maker, I had to establish the target laboratory that would provide target materials to be used in experiments conducted by researchers in nuclear and other fields,” she says. “My daily work activities at iThemba LABS involved various disciplines in science, especially Physics and Chemistry - and this stimulated my passion to continue with my postgraduate studies.”

In October last year her work bore fruit for the first time. At iThemba LABS, beams of 60Ni8+ and 62Ni8+ were produced and accelerated. Together with the GAMKA array, these new beams developed from Dr Kheswa’s research will allow the investigation of fundamental nuclear physics and nuclear astrophysics, from benchmarking modern state-of-the-art theoretical predictions to estimating the age of the oldest objects in our Universe.

“Ntombi Kheswa has been a freedom fighter all her life - and she is continuing that with her work in science,” says Prof Nico Orce. “She has continued opening the doors to excellence - not only for herself, but for new generations of students to come, in South Africa and beyond. What discoveries and dreams can be reached is now only up to us!”