Intermediate Physics for Medicine and Biology: Robley Dunglison Evans Medical Physicist
 |
The Atomic Nucleus,
by Robley Dunglison Evans. |
One sentence, and sometimes even one word, can hide a story. For instance, a footnote in Chapter 17 of
Intermediate Physics for Medicine and Biology cites
The Atomic Nucleus (McGraw-Hill, 1955), a book by
Robley Dunglison Evans. His story is told in three
oral history interviews on the
American Institute of Physics website (you can find them
here,
here, and
here).
Evans was born in
University Place, Nebraska in 1907. When he was five his family moved to California. He won a scholarship to the
California Institute of Technology, where he studied math and science, and earned spending money playing drums in a jazz band. He considered majoring in the
history of science, but ultimately decided to focus on physics. He remained at
Caltech for graduate school analyzing
cosmic rays.
Nobel Prize winner Robert Millikan was his thesis advisor.
I enjoyed his reminiscences about
1932, that
famous year in nuclear physics when the
deuteron,
positron, and
neutron were all discovered.
Carl Anderson, who
first detected the positron, was at Caltech photographing cosmic ray particles using a
cloud chamber. Evans recalls when
...in one of these pictures, he [Anderson] got a track … [that] looked like an electron, but it was bent the wrong way [by the magnetic field] and had too long a range, too long a path length to possibly be the only positive particle we knew about, the proton. I remember seeing Carl in the morning coming dashing out of the darkroom, and I guess I was the first one he ran into in the hall, and he said, “My God, Bob, look at this. This thing is going the wrong way. And I checked the film in my camera. I didn’t have the emulsion facing the wrong way; I had it the right way. Everything looks all right here, and I can’t imagine what possibly is wrong, but maybe [it’s] that damn Pinky Klein,” who was a practical joker with a well-established reputation … So Carl suggested that maybe Pinky had reversed the magnetic field on him just to play a joke…
Of course it wasn’t Pinky. Anderson won the
Nobel Prize for his discovery of the positron, a positive electron.
Nowadays physics grad students often complain about their job prospects, and rightly so. But the situation was worse in 1932 during the depths of the
Great Depression. Evans says “I remember that some of them [the grad students] like Jack Workman who was there urged several of us to join together to go to the state of Washington and grow apples, and we fresh new PhD’s in physics were to become apple farmers. It was that bad.”
But not that bad for Evans himself. After graduating, he started a post doc at
Berkeley. In 1934, he accepted a job on the faculty at
MIT, where he taught the first class in the United States about nuclear physics.
The Atomic Nucleus grew out of this class. He started writing the book by creating a giant card file, with the abstract of every nuclear physics research article written out, one per card.
He became interested in the medical applications of nuclear physics after hearing about
watch dial painters who swallowed
radium paint and got cancer. (The recently published book
The Radium Girls by
Kate Moore tells the story; it's on my list of books to read this summer.) Also, at that time people like
Eben Byers were drinking
radium water as a tonic. Evans claimed “We know of one physician in Chicago, for example, who injected more than a thousand patients, the normal regime being 10
microcuries intravenously once a week for a year! That’s 500 microcuries or half a millicurie.”
Evans become an expert in the new field of
nuclear medicine. Based on his studies, he estimated the largest permissible load of radioactivity for a person was 0.1 microcurie. This value was something of a rough guess, but has held up well over time.
I was surprised that during
World War II Evans was not at
Los Alamos helping to build the
atomic bomb. He did, however, carry out war work. For instance, he was responsible for measuring radioactivity in the Belgian uranium ores brought from the
Congo for the
Manhattan Project. He also invented a scheme to mark land mines with the radioactive isotope
cobalt-60, so if American troops had to retake ground previously mined, they could easily detect and remove the mines. Finally, he created a technique to monitor the preservation of blood using radioactive iron as a tracer.
Evans developed a method to use radioactive
iodine to diagnose and treat
goiter.
He taught at MIT until his retirement in 1972. As a student,
IPMB author
Russ Hobbie took a class with Evans in statistical nuclear physics, based on Chapters 26-28 in
The Atomic Nucleus.
Evans won many awards throughout his career, including the
Enrico Fermi Award for pioneering work “in measurements of body burdens of radioactivity and their affects on human health, and in the use of radioactive isotopes for medical purposes.” Robley Evans died in 1996, at age 88. You can read his obituary
here and
here.
The Atomic Nucleus was a leading
nuclear physics textbook of its day, and according to
Google Scholar it has been cited nearly 4000 times. If interested in reading
The Atomic Nucleus, you can download it free online at
https://archive.org/details/TheAtomicNucleus.
You never know what tales lie buried beneath each word of
IPMB.
