Symposium on Accelerator Mass Spectrometry

509 Pages·2004·9.14 MB·English

AHL/PHY--81-1
DE82 007875
SYMPOSIUM ON ACCELERATOR MASS SPECTROMETRY
Argonne National Laboratory
Argonne, Illinois 60439
11 - 13 May 1981
A limited number of copies
of this report are available
for general distribution.
For further copies contact
W. Kutschera, Physics Division,
Building 203,
Argonne National Laboratory,
Argonne, Illinois 60439.
OF THIS OOCUMEKT It
IWTIbOOUCTIOK
The area of accelerator aass spectroawtry has expanded
considerably over the past few years and, i^ our opinion, indeed
established itself as an independent and interdisciplinary
research field. Three years have passed since the first Meeting
was held at Rochester, and we felt it tiaely to gather and
discuss the recent developments and present status of the field.
A Symposium on Accelerator Mass Spectrometry was held at Argonne
on May 11-13, 1981. In attendance were 96 scientists of which 26
were from outside the United States. The present proceedings
document the program and excitement of the field. Papers are
arranged according to the original program. A few papers not
presented at the meeting have been added to complete the information
on the status of accelerator mass spectrometry.
Much of the success of the program was due to the advice
from our program committee: H. R. Andrews (Chalk River),
H. E. Gove (Rochester), E. T. Hall (Oxford), A. E. Litherland
(Toronto), R. Middletcn (Philadelphia), R. A. Muller (Berkeley),
K. H. Purser (General Ionex Corporation), G. Raisbeck (Orsay),
and 3. P. Schiffer (Argonne). We should like to thank the
members of the program committee and all participants of the
meeting for contributing to its success.
Walter Hsnning
Walter Kutschera
Robert K. Smither
Jan L. Yntema \
/
(The Organizing Committee)
ii
TABLE OF CONTENTS
Morning Session, 11 May 1981: Chairman, R. A. Muller
PRELUDE
THE EARLY DAYS OF ACCELERATOR MASS SPECTROMETRY . . . . .. 1
L. W. Alvarez
THE CHALLENGE FROM LOW-ENERGY MASS SPECTROMETRY
G. J. Wasserburg (presentation only)
PROGRAMS AT EXISTING ACCELERATORS
ULTRASENSITIVE MASS SPECTROMETRY WITH A TANDEM
VAN DE GRAAFF ACCELERATOR 16
H. E. Gove
ACCELERATOR MASS SPECTROMETRY WITH THE GRENOBLE AND
ORSAY CYCLOTRONS 23
G. M. Raisbeck and F. Yiou
RADIOCARBON DATING WITH THE CHALK RIVER MP TANDEM
ACCELERATOR 34
G. C. Ball, H. R. Andrews, R. M. Brown,
N. Burn, W. G. Davies, Y. Imahori and
J. C. D. Milton
Afternoon Session, 11 May 1981: Chairman, A. E. Litherland
PROGRAMS AT EXISTING ACCELERATORS (continued)
THE ROLE OF ACCELERATOR MASS SPECTROMETRY IN NUCLEAR
PHYSICS 43
W. Kutschera
INSTRUMENTATION OF AN FN TANDEM FOR THE DETECTION OF
lOBe 57
R. Middleton, J. Klein and Hongqing Tang
IMPROVEMENTS IN THE APPLICATION OF A TANDEM VAN DE GRAAFF
ACCELERATOR FOR ULTRA-SENSITIVE MASS SPECTROMETRY 87
M. Suter, R. Balzer, G. Bonani, Ch. Stoller,
W. Wolfli, J. Beer, H. Oeschger and B. Stauffer
ACCELERATOR MASS SPECTROMETRY AT THE UNIVERSITY OF
WASHINGTON 100
G. W. Farwell, F. H. Schmidt and P. M. Grootes
iii
Table of Contents (cont'd)
PLAN FOR MASS ACCELERATOR SPECTROMETRY AT GIF-SUR-YVETTE
AND SACLAY 120
B. Berthier, L. Bianchi, 6. Delibrias and
Y. Koechlin
REPORT ON ACCELERATOR MASS SPECTROMETRY EXPERIMENTS AT
THE REHOVOT 14UD PELLETRON 130
M. Paul, R. Kaim, A. Breskin, R. Chechik, J. Gerber,
M. B. Goldberg, N. Zwang and A. Kaufman
(not presented)
SEARCH FOR EXOTIC PARTICLES
SEARCH FOR ANOMALOUSLY HEAVY ISOTOPES 136
J. Klein, R. Middleton and W- E. Stephens
RECENT SEARCH FOR QUARKS AND VERY HEAVY HYDROGEN ISOTOPES
USING AN (ALMOST) ALL-ELECTROSTATIC SYSTEM 154
J. P. Schiffer, H. Ernst, W. Henning and
W. Kutschera
A MASS-INDEPENDENT SEARCH FOR FRACTIONALLY CHARGED
PARTICLES 157
K. H. Chang, A. E. Litherland, L. R. Kilius,
R. P. Beukens, W. E. Kieser and E. L. Hallin
A SEARCH FOR ANOMALOUS HYDROGEN IN ENRICHED D-O, USING A
TIME-OF-FLIGHT SPECTROMETER 7 170
P. F. Smith, J. R. J. Bennett, G. J. Homer,
J. D. Lewin, H. E. Waiford and W. A. Smith
(not presented)
Morning Session, 12 May 1981; Chairman, P. Parker
APPLICATION TO VARIOUS ISOTOPES
APPLICATION OF AMS TO HYDROLOGY 193
H. W. Bentley and S. N. Davis
10Be IN THE ENVIRONMENT: SOME RECENT RESULTS AND THEIR
APPLICATIONS , 228
G. M. Raisbeck, F. Yiou, M. Lieuvin, J. C. Ravel,
M. Fruneau and J. M. Loiseaux
10Be IN MANGANESE NODULES 244
J. Thomas, P. Parker, ft. Mangini, K. Cochran,
T. Turekian, S. Krishnaswami and P. Sharma >.
iv
Table of Contents (cont'd)
Page
THE PREPARATION OF A Be STANDARD 255
J. Southon, I. Thorson, D. E. Nelson, R. Korteling,
J. S. Vogel, T. L. Ku, J. L. Reyss and I. Nowikow
MEASUREMENT OF COSMOGENIC NUCLIDES IN EXTRATERRESTRIAL
MATERIAL 262
K. Nishiizumi and J. R. Arnold
TANDEM VAN DE GRAAFF MEASUREMENT OF 10Be IN METEORITES . . 277
T. H. Kruse, R. Moniot, G. Herzog, T. Milazzo,
G. Hall and W. Savin
EARTHQUAKE DATING BY 14C ATOM COUNTING 285
A. B. Tucker, G. Bonani, M. Suter and W. Wolfli
Afternoon Session, 12 May 1981; Chairman, A. M. Hoogenboom
APPLICATIONS TO VARIOUS FIELDS (continued)
STABLE ISOTOPE APPLICATIONS OF AMS IN GEOLOGY 293
J. C. Rucklidge
RARE STABLE ISOTOPES IN METEORITES 310
G. C. Wilson
ACCELERATOR MASS SPECTROMETRY OF 59Ni AND Fe ISOTOPES
AT THE ARGONNE SUPERCONDUCTING LINAC 320
W. Henning, W. Kutschera, B. Myslek-Laurikainen,
R. C. Pardo, R. K. Smither and J. L. Yntema
SEARCH FOR THE 36C1 ISOTOPE IN NATURAL SAMPLES BY CYCLOTRON
OR TANDEM ACCELERATORS 330
I. Brissaud, J. Kalifa, H. Laurent, J. C. Roynette,
C. Zaidins, J. C. Fontes, J- M. Gamier, J. Guillot,
A. Peghaire, S. Plattard and J. Uzureau
(not presented)
THE MUNICH ATTEMPT TO DETECT 36C1 . . . 34*
P. W. Kubik, G. Korschinek, E. Nolte,
M. S. Pravikoff and H. Morinaga
Morning Session, 13 May 1981; Chairman, R. Middleton
SPECIFIC PROBLEMS IN ACCELERATOR MASS SPECTROMETRY
MASS SPECTROMETRY WITH A VERY SMALL CYCLOTRON 342
R. A. Muller, P. P. Tans, T. S. Mast and
J. J. Welch
#
REPRODUCIBILITY OF ISOTOPE RATIO MEASUREMENTS 346
D. Elmore
v
Table of Contents (cont'd)
Page •_)
ZSOTOPIC FRACTIONATION IN ACCELERATOR BASED RADIOCARBON
DATING 359
N. R. White
THE INVERTED SPHERICAL IONISER SPUTTER ION SOURCE (IS3) . . 373
N. R. White
OSIRIS 381
S. H. Chew, E. F. Garman, T. J. L. Greenway and
K. W. Allen
BROAD BAND MASS ANALYSIS AT MeV ENERGIES 391
L. R. Kilius, K. H. Chang, E. L. Hallin and
A. E. Litherland
CALIBRATION SAMPLES FOR ACCELERATOR MASS SPECTROMETRY . . . 401
R. L. Hershberger, D. S. Flynn and F. Gabbard
PRODUCTION OF CHARCOAL FOR ACCELERATOR TARGETS 404
S. W. Leavitt, D. J. Donahue and A. Long
SAMPLE PREPARATION FOR ACCELERATOR MASS SPECTROMETRY AT THE
UNIVERSITY OF WASHINGTON 405
P. M. Grootes, M. Stuiver, G. W. Farwell and
F. H. Schmidt
THE PRODUCTION OF SMALL CARBON SAMPLES BY R.F. DISSOCIATION 416
OF ACETYLENE
R. P. Beukens and H. W. Lee
INSTABILITY OF KH~ AND POTENTIAL IMPLICATIONS FOR DETECTION
OF 41Ca WITH A TANDEM ELECTROSTATIC ACCELERATOR 426
G- M. Raisbeck, F. Yiou, A. Peghaire, J. Guillot
and J. Uzureau
Afternoon Session, 13 May 1981; Chairman, G. Raisbeck
DEDICATED FACILITIES
A PRELIMINARY DESCRIPTION OF A DEDICATED COMMERCIAL
ULTRA-SENSITIVE MASS SPECTROMETER FOR DIRECT ATOM
COUNTING OF I4C 431
K. H. Purser, R. J. Schneider, J. McG. Dobbs and
R. Post
THE ISOTRACE LABORATORY AT THE UNIVERSITY OF TORONTO . .. 463
R. P. Beukens
vi
Table of Contents (cont'd)
Page
THE RADIOCARBON FACILITY AT THE RESEARCH LABORATORY FOR
ARCHAEOLOGY IN OXFORD - A REVIEW 472
N. R. White, R. E. M. Hedges, J. O. Wand and
E. T. Hall
THE N.S.F.-ARIZONA DEDICATED FACILITY 484
D. J. Donahue
THE RESEARCH PROJECT AT NAGOYA UNIVERSITY 488
H. Furukawa, N. Nakai and E. Nakano
LIST OF PARTICIPANTS < 491
AUTHOR INDEX ,
Vii
THE EARLY DAYS OF ACCELERATOR MASS SPECTROMETRY
Lids W. Alvarez
Lawrence Berkeley Laboratory
University of California
Berkeley, CA 94720
Before 1978, there were just three papers that bad reported work in high energy
mass spec trow e try—two in 1938, by me and my student Robert Ccrnog, and one in 1977,
a preprint by another of my students, Richard Muller, and me. But a Tear later, Rich
Muller published his classic paper on accelerator dating, and used a cyclotron to
determine the age of a water sample from its Tritium content. This paper clearly
outlined the techniques of C dating by accelerator, and it was published before anyone
else started to work on this now important field. Although he mentioned the usefulness
of linear accelerators, he did not refer explicitly to the tandem accelerator, which is now
the most widely used instrument. The fact that several tandem machines are now being
dedicated to accelerator dating gives me an excuse to tell you of my involvement in the
origin of charge exchange acceleration, an interesting story that is not part of the
general lore of physics.
I have an intense dislike of pictures of the white-haired Albert Einsten because he
was then no longer the wonderfully creative physicist who gave us special and general
relativity. I have a picture of the real Einstein on my desk—a very young patent
examiner who did marvelous things in his spare time. And although I am exceedingly
interested in the history of physics, I have recently declines invitations to two
conferences on the subject. That is because I would rather remember my friends who did
pioneering work in nuclear physics as the vigorous young men they were, four and half
decades ago, instead of the white-haired old men I would meet at such conferences and
see in my shaving mirror. j£milio Segre brought this problem into focus for me at a talk
he gave a few years ago on the life of Enrico Fermi. He told of Fermi's first visit to
Gottingen, "where he met the boys who made quantum mechanics."
So ni be telling you about what a couple of boys did in 1939, what a young man did
in 1951, and what another young man and a now older man did in 1977, all of which was a
prologue to this meeting. I should apologize for talking so much about my own work,
even though that is what I was asked to do. In case you think I seem carried away by its
importance, Til ask you to remember that in 1977 I had stored away in various parts of
my brain all the facts that Rich Muller put together to come up with the concept of
accelerator dating. If I can get you to ask the appropriate question, "How could anyone
know all that Alvarez knew about the techniques, the dating problem, and its importance,
and not arrive at the solution?", I will perhaps help you to put my remarks today in their
proper perspective.
Fll make one more comment on my reasons for accepting this speaking
assignment. I have always been unhappy about scientific history because, in my view, it
so often skirts what I think is the most important element in a new observation or
theory—how did this person happen to be doing this thing or thinking • -g these new
lines? So, in a sense, I'm giving this talk to take you behind the scenes, to help you
understand how I happened to be mixed up in three unusual projects.
I arrived in Berkeley, in May of 1936, with a brand new Ph.D. and essentially no
knowledge at all of nuclear physics; I had worked with Arthur Compton in the field of
cosmic rays. Very fortunately for me, the first of Hans Bethe's three monumental
articles on nuclear physics appeared in the April 1936 issue of the Reviews of Modern
Physics. I studied "Bethe's Bible" with great diligence, and very quickly I was "up to
speed" in that I knew all kinds of important things about nuclear physics that even my
new and experienced colleagues hadn't known the week before. Hans Bethe was making
his transition from spectroscopist to nuclear physicist, and, in his characteristically
thorough manner, he learned everything that had been done in his new field, added a lot
of new ideas and calculations, and, most importantly for the rest o' us, put it all down in
very clear prose.
In addition to learning almost everything I knew about nuclear physics from those
wonderful articles, I was most fascinated by several things that Hans said couldn't be
done with the then present state of the art; and I worked on several of them. (Some of
them became possible when reactors were built.) My most successful venture was
discovering nuclear K-electron capture, a mode of decay I learned about from his article,
which he said couldn't be directly observed because nothing was emitted except a
neutrino. I corrected a minor error in one of his papers when I showed that internal
conversion of gamma rays occurred in Ga; he had said that such an effect could only be
seen in the heavy "natural" radioactivities. The next of his "unobservables" that 1 tried
to observe was the beta-decay of the free neutron, which I wouldn't have known about
except for his article. He said, "The lifetime is too long to allow observation of the
beta-decay of neutrons." The last pre-World War II experiment to be set up at the
Berkeley 37-inch cyclotron was a search for that decay; my graduate student
collaborator was Cornelius Tobias, and the experiment was terminated when the
cyclotron was reconfigured as a mass spectrometer to separate the uraniusa isotopes.
Robert F. Mozley and I tried a different technique, using our Van de Graaif generator as
a source, tc observe the neutron decay after the war; but before it was successful, Art
Snell of Oak Ridge and John Robson of Chalk River both did such good jobs using reactor
neutrons that we were effectively "wiped out.* (An interesting aspect of our unpublished
work was the first observation that charged particles—electrons, in our case—could be
stored in a "magnetic bottle" for long periods cf time; this clue may help some of you to
reinvent our experiment.) My last challenge of this kind involved Bethe's statement that
"the probability of the disintegration of nuclei by neutrinos is so unobservably
small—." Shortly after the war when all papers on nuclaar physics were born "classified,"
Bruno Pontecorvo and I independently suggested that neutrino interactions could be
observed in OCL^, and if the Majorana theory was correct, anti-neutrinos from reactors
could also be so observed. (My very long paper, which discussed the many sources of
background counts, was declassified about ten years later.) As you all know, Ray Davis
hits spent about twenty years looking for solar neutrinos by this technique, and shewing
very importantly that the sun produces only about one third as many neutrinos as theory
says it should.
One of the problems to which Bethe devoted a lot of attention involved Helium 3
and Hydrogen 3. He didn't question the universal belief that He was heavier than the
stable H, and he quoted experimental results, from the D-D reaction energetics, to
indicate that He was about 0.2 Mev heavier than H and should capture an electron to
3 3 3
become F with a "lifetime of about 5,000 years." He and H had of course been
observed for the first time, as high speed reaction products from D+D collisions, by
Oliphant, Harteck, and Rutherford in 1934. It was as though the alpha particle had been
discovered but the Helium atom had not yet been seen—neither of the nuclei of mass
three had been observed after they had come to rest, although several mass
spectroscopists had incorrectly reported that they had seen stable H in enridral water
samples. The best way I know to show that everyone (and I don't even need to put
quotation marks around that word) believed H to be stable is to tell you of the very last
paper Lord Rutherford published. It appeared in Nature, just 414 pages before the
announcement of his death, and was entitled "Search for the Isotopes of Hydrogen and
Helium of Mass 3." Rutherford made arrangements with the Norwegians to process
nearly 50 kg. of 99.2% heavy water by further electrolysis down to a volume of 11 cubic
centimeters. The overall reduction in water volume was about a factor of 10 . Aston
used his mass spectrometer to examine this sample, and reported that he could find "no
trace of H"; Rutherford ^as "very disappointed after the time and labor spent in