Bookshelf

From Hiroshima to the Iceman

From Hiroshima to the Iceman: the Development and Applications of Accelerator Mass Spectrometry by Harry E Gove,
Institute of Physics Publishing 07503 0557 6 (hbk £50/$99) 07503 05584 (pbk £15/$27).

Invented some 20 years ago,
accelerator mass spectrometry (AMS) is one of the newer success stories in the applications of particle accelerators. It provides a powerful,
fast and reliable means of measuring long-lived radio-isotopes using only minute samples.

Radiocarbon-14,
which has a half-life of 5730 years,
was the first isotope to be measured this way,
and AMS radiocarbon dating soon became a powerful tool for determining the age of organic material using small samples. Other isotopes are also suitable for AMS.

Radiocarbon dating was invented by Willard Libby in the 1940s and brought him the 1960 Nobel Prize for Chemistry. In its original form,
radiocarbon dating counted the actual decays of residual carbon­14,
requiring relatively large samples of material.

Jolted by news of carbon­14 measurements at a Berkeley cyclotron,
Gove participated in pioneer AMS measurements at Rochester in 1977,
which dramatically showed how the level of carbon­14 in commercial charcoal and fossil graphite is different,
using milligram samples. It is usually no problem to take a milligram sample from even the most valuable relic.

Giving a reliable measurement of the age of a specimen can be vital input in archaeology,
history and mineralogy,
as well as being a focus of public interest. Such measurements can settle disputes and separate fact from myth.

One of the most spectacular AMS applications is the dating of the Turin Shroud,
and Gove’s earlier book,
Relic or Hoax?: Carbon Dating the Turin Shroud,
is a scientific account of this work. Multiple AMS measurements gave the origin of the shroud material,
widely believed to be of biblical origin,
as AD 1325 ±33 years.

In his latest book,
Gove casts the AMS net wider,
describing the history and instrumentation of the technique,
concentrating on electrostatic tandem accelerators,
before turning to its application. The analysis examples,
described in graphic detail,
include radio-relics from Hiroshima and Nakasaki that provided new insights into the mechanisms of radiation damage; North American archaeological remains; modern radioactive waste; the Turin Shroud revisited; Egyptian mummies; “Oetzi”,
the neolithic iceman discovered in 1991 in the Alps on the Austrian-Italian border; and the Dead Sea Scrolls.

For the dating of the Turin Shroud,
one theory mentioned is that bacteria on cloth continue to ingest carbon­14 from the air,
making the cloth look younger.

This is a fascinating account of a major particle accelerator application success by an enthusiastic scientist who played a major role in its development.
Harry Gove contributed an article on AMS to the
special July 1995 Applying the
Accelerator issue of CERN Courier.

Making Physics

Making Physics: a Biography of Brookhaven National Laboratory,
1946­1972 by Robert P Crease,
University of Chicago Press 0 226 12017 1 (446pp $38/£30.50).

Crease calls this book a biography because he likens Brookhaven National Laboratory to a community,
and a community lends itself to biographical treatment. Crease is a philosopher,
but he has absorbed and is faithful to the ethos of the scientific community.

I have been at Brookhaven for 44 years but found much in this book that I did not know about the
place.
Crease had full access to the
laboratory’s archives and
had interviews with many of the
personnel.
I found the
book fascinating and
a good read.
He recounts the
history of the
founding of Brookhaven;
the
drive by I I Rabi to obtain large physics instruments for the
east of the
US after the
Second World War;
the
interactions with the
Manhattan District of the
US Army,
which had built the
atomic bombs;
and
the
finally successful negotiations with the
Federal Government for the
establishment of the
laboratory at the
US Army’s Camp Upton site.

Brookhaven was the
first civilian laboratory to have a reactor.
Along with the
reactor it was decided that accelerators would also be built there.
The first two were a Van de Graaff and
a 60 inch cyclotron.
Both of these machines were built by commercial companies and
neither worked properly until significantly altered by laboratory personnel.
Rabi was insistent that a large synchrotron should be built at Brookhaven.
In a compromise worked out with the
funding agency and
Berkeley,
it was agreed that Brookhaven would build a 2­3 GeV machine and
Berkeley a 8 GeV machine with Brookhaven to get the
follow-on machine later.

After the
Cosmotron was finished,
the
Brookhaven accelerator builders were informed that a delegation of accelerator builders from a new laboratory,
called CERN (modelled to a considerable extent on Brookhaven),
would be visiting with plans to build a machine more ambitious than the
Cosmotron.
Livingston felt that Brookhaven should do more than just show and
tell,
and
organized a study group to brainstorm for improvements on the
Cosmotron’s basic design.
Crease narrates how this study group came up with the
ideas for alternating gradient synchrotrons.
When the
CERN group arrived they were caught up in the
excitement,
changed their plans and
resolved to build what became the
PS.
Brookhaven built the
AGS,
which came on line shortly after the
PS.

Crease goes into considerable detail about the work done in particle physics,
in nuclear physics (both at the reactors and the accelerators) and in solidstate physics. Brookhaven is a multidisciplinary laboratory,
and while Crease’s emphasis is on physics,
there is also information about some of the work in other disciplines,
such as medicine,
chemistry,
instrumentation and biology. He cites the development of Tc99 as used in nuclear medicine. It is the predominantly used radionuclide in the several million nuclear-medicine procedures performed today.

Other fruitful developments include the
first treatment for Parkinson’s disease and
the
effect of salt on hypertension.
Ray Davis’s work on the
detection of solar neutrinos was done in the
chemistry department with help from the
instrumentation department.

Science is made by human beings.
Crease emphasizes the
human side of Brookhaven,
with miniportraits of many of the
prominent personalities associated with the
laboratory.
He describes in some detail its administration,
the
interaction of scientists with the
administration and
how scientific policy is set.
He describes interactions among strong-willed personalities and
how some of this impacts the
research done.
He explains the
science well and
made remarkably few errors.


David C Rahm,
Brookhaven.