GRADUATE PROFILE
A passion for physics leads to medal
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B.M. Harrison, Honorary
he Executive Committee.
Varnan Gradu ate Award,
Sydney, NSW
2006.
g date for appli cation s is
nber 22, '989.
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Dr Joan Freeman was Ihe joint winner of the Rutherford medal in 1976, for work she and Professor ,-:
Roberl Blin-Stoyle carried oul on Ihe bela radioactivity of complex nue/ei, No other woman has
been awarded Ihis prestigious prize by the British Institute for Physics, and only one other
Australian has been a winner before, Sir Mark Oliphant,
'ArainbOW is a beautiful thing. You
can write poetry about it or take
pictures of it, but if you can also
understand why it is formed by the refraction
of the sun's rays, you gain another insight
into it which is exciting, stimulating and
awe-inspiring. '
A thoughtful Joan Freeman has been
asked 1O reflect on her achievements. Others
may wonder about the kind of perseverance
she must have shown in order to become a
physicist, when ve ry few of her women
contemporaries even considered it as a
possible career option. To her it's
straightforward - she was and always has
been driven by a passion for physics.
Joan was born in Perth in 1918; she
describes herself as 'undersized and rather
shy'. When she was 4 years old, her family
moved to Sydney.
Young Joan's interest in scie nce was
prompted by two prized possessions: a
Meccano set and the ten volumes of the
Arthur Mee's Children Encyclopedia, in
which she avidly read about the formation
of the Earth, the nature of matter and the
stars.
She still remembers her excitement when,
one breakfast time in 1932, her mother
pointed to a short and rather obscure item
in the morning paper about twO physicists,
Drs Cockcroft and Walton, splitting the atom
in the first artificially induced nuclear
disintegration, at the Cavendish Laboratory
in Cambridge. Joan took the newspaper to
sc hool and asked a disgruntled chemistry
teacher about it ... after all, she had been
taught that an atom was the smallest quantity
of any element and could not be divided.
After passing her intermediate certificate,
Joan was faced with a dilemma. Her school,
in keeping with most girls' schools in Sydney
at the time, taught no chemistry for the
leaving certificate and had hardly even heard
of physics but she had been told that, in order
to do science at Sydney University, she would
need at least one o f those.
Someone suggested to her that she might
be able to attend evening classes in chemistry
or physics at the Sydney Technical College.
The head of chemistry refu sed to accept a
schoolgirl but the more en lightened head of
physics took her on.
She obtained the top NSW scholarsh ip for
her leaving certificate and went on to enrol
in a science degree at Sydney University.
In her second year she had to decide
whether to major in physics or chemist ry. A
number of people, including a Women's
College tutor, Phyllis Nicol, who had been
the second woman to graduate with honours
Dr Joan Freeman was group leader for Harwell's
Tandem accelerator.
in physics at Sydney University. advised her
that chemi st ry was a better bet for a woman .
An eccentric but brilliant Professor of
Experimental Physics, Dr V.A. Bailey, talked
her into following her inclinations.
Joan gained her Bachelor of Science degree
with first class honours in 1939, and followed
that by graduating with a Master of Science.
'My life would have been completely different
if World War Two had not happened,' she
admits now. ' I probably would never have got
a job. I was lucky in that the war brought
first radar then atomic energy which meant
that a tremendous number of people were
required in physics. I was encouraged, even
though it was pure research rather than
applied research that I was interested in.'
In 1941 she joined the CSIRO
Radiophysics Laboratory in Sydney. where all
Australian wartime radar research and
development was being carried out. She
worked under Dr J.L. Pawsey, another
inspiring experimental physicist, who later
became the father of radioastronomy in
Australia.
In September 1946 a CSIRO scholarship
landed her in none else than the Cavendish
Laboratory in Cambridge. 'My logical choice
of subject there would have been
radioastronomy but Dr Pawsey himself
pointed out that radiotelescopes around
Sydney were located on field stations where
condition s were primitive, without suitable
facilities for a woman. So, inspired by all
accounts I had heard and read of the great
Rutherford era of the 1930s at the laboratory,
I elected to do nuclear physics for my PhD,'
she says.
By perseverance and some subterfuge she
found her way into a group that was using
the 1 million volt accelerator, the successor
of the original Cockcroft-Walton machine, to
car ry out innovative experimental nuclear
stud ies under the guidance of Dr W.E.
Burcham.
She then joined the Van de Graaff
accelerator group in the nuclear physics
division of the Atomic Energy Research
Establishment at Harwell, in England, which
was under the directorship of Dr John
Cockcroft himself.
In 1960 she became leader for the group
centred around the newly built Tandem Van
de Graaff accelerator, a 6 million volt
machine in a 22 metre high tower, Harwell's
pride and joy. She initiated her own line of
research on the Tandem, on the beta decay
of some specific short lived radioactive nuclei
which could be generated from reaclions in
the accelerator. The accurate measurements
of the energy they released and their half lives
could be used to test the validity of
fundamenta l theoretical predictions which
had recently been made about the whole
process of bela decay.
Joan says that, while she did not fully
understand lhe theory she remembered that,
while she had been on sabbatical leave at the
Massachussets Institute of Technology a year
earlier, she had mel a pleasant and
approachable theoretical physicist, Professor
Roger Blin-Stoyle, on study leave from
Oxford, who was interested in theories of
beta decay and the 'weak interaction process'
as it came to be called.
Thus began a long and fruitful
collaboration, culminating in experimental
support for a new theory unifying the weak
and electromagnetic forces - the first step
towards lhe elusive goal of unification of all
the forces of nature.
'This was heady stuff for a simple
experimental physicist like m~ to be involved
in,' Joan says. One day in 1976 she received
a letter from the British Institute of Physics
telling her that Professor Blin-Stoyle and
herself had been awarded jointly the
Rutherford medal for that year.
Two years later Joan retired. She still lives
near Harwell and does voluntary work for
the establishment on the computerised
indexing of recent scientific literature.
She is also writing an autobiography which
she hopes to complete by next year. ' I have
felt very privileged. Being a physicist has been
more than just a vocation for me; it has been
an enormous pleasure.'
By Manuela di Piramo
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THE GAZETTE, SEPTEMBER 1989
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