On New Year’s Day, 2023, Richard Lanza had an extra reason to celebrate. Lanza, a Senior Research Scientist in the MIT Department of Nuclear Science and Engineering, had just become an IEEE (Institute of Electrical and Electronics Engineers) Fellow — an honor annually bestowed on just one-tenth of one percent of the members of what’s called “the world’s largest technical professional organization.” His fellowship appointment was “for developing novel imagers and radiation detectors applied to medicine and security problems.” That, however, is an abbreviated version of a much longer, and more involved, story.
Lanza earned a PhD in Physics from the University of Pennsylvania in 1966 and came to MIT later that year as a postdoctoral fellow. He soon took part in investigations into the structure of the proton—work that ultimately validated the quark model of particle physics. Lanza’s primary role was in designing and building the radiation detectors used in experiments carried out in the late-60s and 70s at the Stanford Linear Accelerator Center (SLAC).
About 15 scientists collaborated in the last experiment Lanza worked on at SLAC, which took place around 1975. But the trends in particle physics were clear to him: the next experiment would likely have more than 100 scientists, and before long there’d be thousands. It would become harder to try out new ideas, and the enterprise would allow less room for creativity — a prospect he was not enthused about.
Upon returning to MIT from Stanford, he spoke with a friend, a radiologist at the Massachusetts General Hospital (MGH), who asked him what he’d been up to. When Lanza mentioned the proton’s structure, his friend quickly changed subjects. “With all your cleverness in detectors,” he asked, “why not help us out in medicine and radiology?”
Intrigued by that proposition, Lanza soon joined a group, based jointly at MIT and MGH, which was building one of the first computed tomography (CT) scanners that could rotate fully around a patient. He got started in this work in 1975 and spent more than 20 years as a radiology associate at the Harvard Medical School, though his primary affiliation has always been with MIT.
Lanza and colleagues set out to improve single-photon emission computed tomography (SPECT), an imaging technique that used gamma rays. One challenge is that gamma rays can’t be focused with lenses or mirrors. “You could use a pinhole, but then you’d end up throwing away almost the entire signal,” Lanza explains. One way around that was to utilize a so-called coded aperture—a sheet of tungsten with dozens, hundreds, or thousands of holes—and then rely on a computer to combine the separate, overlapping images into a single composite view. Coded apertures had been important in x-ray astronomy since 1965, and Lanza felt that medical imaging could benefit from them as well. “A big advantage is that you can get 3D images with no moving parts,” he says.
His career took a dramatic turn in December 1988, when a bomb that had been concealed aboard a Pan Am aircraft exploded over Lockerbie, Scotland, destroying the plane and killing everyone in it — all 259 passengers and crew members — plus 11 people on the ground. “A complete panic set in after that plane blew up,” Lanza says. He was immediately approached by his colleague, MIT physicist Lee Grodzins, who asked, “Do you have any idea how we can detect explosives in luggage?”
Lanza turned his attention to that problem. Conventional explosives (like TNT), he reasoned, contain dense clusters of nitrogen, in particular, as well as oxygen and carbon. One could send a beam of neutrons through the materials inside a suitcase. If gamma rays of a particular energy were produced through this interaction, he says, “that would tell you if large quantities of nitrogen were concentrated.” The detection system he devised again incorporated coded apertures.
There was a catch: Although military explosives contained a lot of nitrogen, he says, “we discovered that there is a whole world of homemade explosives that terrorists might use that don’t have any nitrogen at all, making it a very complicated business.” Lanza also explored ways of finding improvised explosive devices (IEDs), such as those planted in cars during the Iraq war, which posed similar imaging and detection challenges.
In the late-1990s, Lanza got involved in humanitarian demining. Landmines can be made for less than $2 apiece — one reason why millions of them are still left in former or current war zones, waiting to go off if anyone ventures close enough. He designed a simple device, consisting of portable neutron sources and gamma ray detectors, which could effectively survey small areas. He determined that additional approaches — including magnetic detectors and ground-penetrating radar — could be helpful in clearing larger regions, such as the border zones between nations.
Lanza also applied his expertise to the matter of nuclear materials proliferation, finding ways to detect faint radioactivity signals from uranium and plutonium that terrorists might try to smuggle into the country. In a project with Raytheon, he developed a system that could detect radioactive materials at a distance while carried in a moving vehicle.
“Just about everything I’ve done involves imaging of some sort, which is basically a tool that enables you to pick out objects in a background,” Lanza says. He even figured out a method, utilizing neutron imaging, that enabled the De Beers company to find diamonds more efficiently in rock.
In his lengthy career, Lanza has contributed to many other areas (one could almost fill an article just listing them), and he still has a few projects underway, even though he’s now in his 80s and semi-retired. He credits the wide range of work he’s undertaken to MIT itself, “which makes it very easy for people to cross borders. It really is a remarkable place” — remarkable enough that he extended his original two-year appointment into one that’s going on six decades, and still going strong.
Written by Steve Nadis. Photo by Gretchen Ertl.