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PETER MEYER
January 6, 1920-March 7, 2002
BY EUGENE N. PARKER
PETER MEYER WAS AN experimental physicist who clevotecl
his career to the mysterious origins en c! behavior of the
cosmic rays, contributing substantially to present knowlecige
of the diverse components of the cosmic rays. He was a
frienc! en c! colleague whose presence macle the clay more
interesting en cl the clifficulties less onerous. He was a clevotecl
family man. He and his first wife, Luise Meyer-Schutzmeister,
a prominent nuclear physicist, were enthusiastic skiers,
campers, en cl mountain hikers. Music was a continuing
passion. He was an excellent cellist en cl Luise a pianist.
They participates! in regular chamber music evenings at
their home, for their own pleasure en cl for the pleasure of
those privilegecl to join in or merely to listen. Luise cliecl in
1981, en c! Peter marries! Patricia Spear, a microbiologist, in
1983. Peter and Pat actively pursued their common interest
in music en cl the outdoors en cl travelecl wiclely, in aciclition
to working intensely on their respective research interests.
These many intense activities seemed only to refresh him
for his continuing scientific assault on the elusive cosmic
rays. Peter hac! to give up many of his activities cluring the
last few years of his life clue to illness, but he clicl so with
grace en cl style en cl continual to engage his friends en cl
family with his wit en c! humor.
141
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B I O G RA P H I C A L
EMOIRS
Peter Meyer was born in 1920 in Berlin. He stucliec! at
the Technische Hochschule Berlin with the famous physicist
Hans Geiger as one of his teachers. His Diplom Ingenieur
thesis in 1942 clealt with proportional counters. As the son
of a Jewish physician en cl German mother he was cleniecl
the "honor" of fighting for the fatherIancI, with the result
that he survives! the war as a factory worker. His father also
survived, thanks to the efforts of some of his patients.
After the war Meyer continual his studies in physics at
the University of Gottingen. He obtainer! his Ph.D. in 1948
uncler the direction of Wolfgang Paul (Nobel Prize in physics
in ~ 989) en cl Hans Kopfermann with a precise measurement
of the bincling energy of the cleuteron ~ ~ 949) . He continued
working in experimental nuclear physics at Gottingen, with
a year at the Cavenclish Laboratory at Cambridge University
~ ~ 950) . Then from ~ 950 to ~ 953 he was a staff scientist at
the Max Planck Institute for Physics in Gottingen.
In 1953 Meyer came to the Unitecl States en cl accepted
an invitation from John Simpson to work in the pursuit of
cosmic rays as a research associate in the Institute for Nuclear
Studies at the University of Chicago. His scientific prowess
as an experimentaTist was soon appreciates! at Chicago, en c!
he was appointed assistant professor in the Institute for
Nuclear Studies (now the Enrico Fermi Institute) en cl the
Department of Physics in 1956. He was promoter! to associate
professor (tenure) in 1962 en cl professor in 1966. Meyer
remained at the University of Chicago for the rest of his
scientific career, becoming emeritus in 1990.
It was my goocl fortune to make Meyer's acquaintance
when I arrive cl in Chicago in 1955 to work with John Simpson
on the theoretical implications of the cosmic-ray variations
that Simpson en cl Meyer were observing. Meyer's two sons,
Stephan and Andreas, were born in about the same years as
my daughter en c! son, en c! the chiTciren were soon acquainted!
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PETER MEYER
143
through our socializing. It was Peter's performing with his
cello that encouraged my daughter to take up the violin
en cl my son the cello. Peter was supportive of their musical
activities, even to the extent of locating an excellent oic!
cello in Germany en cl traveling by plane back to Chicago
accompanied by the cello in a monster carrying case. This
was but a small sample of his relationships with the younger
generation. He was a sympathetic mentor en cl supportive
friend of his many Ph.D. students over the years.
Meyer worker! with John Simpson in pursuit of the
mysterious time variations of the cosmic-ray intensity. It must
be unclerstoocl that the term "cosmic rays" is a generic term
for the ionizing racliation coming clown through the atmo-
sphere of Earth. When Meyer began his professional career
in 194S, it hacl just been establishecl that the top of the
atmosphere is continually bombarded from space by energetic
protons, accompanied by a smaller number of heavier nuclei
with speecis up to that of light. The impact of these energetic
protons on the nuclei of the air atoms near the top of the
atmosphere produces all mesons (quickly decaying to ,u mesons)
and gamma rays and leading to electrons, positrons, anti-
protons, neutrons, en c! more secondary protons, which all
come showering down through the atmosphere. These
particles ionize ambient air atoms along the way. IncleecI, it
was the discovery of the slight but ubiquitous ionization of
the air in the laboratory a century ago that lecl to the recog-
nition of the cosmic rays. In 1912 the Austrian physicist
Victor Hess ascenclec! in a balloon to a height of several
thousand feet to fincl that the ionization increases ciramati-
cally with altitude, thereby demonstrating that the ioniza-
tion is causer! by something from outsicle the atmosphere.
The alternative explanation hacl been the recently cliscoverecl
natural radioactivity of the rocks and soil, whose effects
wouic! diminish rapidity upward! from ground! level. With
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B I O G RA P H I C A L
EMOIRS
the external origin of the ionization the term cosmic rays
was coined to refer to whatever was responsible. An cl after
many years of speculation as to the precise nature of cosmic
rays, they turner! out to be mostly energetic protons. Over
the last half century it has been establishecl that the protons
are accompanied by small numbers of heavier nuclei en cl
by a few electrons, positrons, en c! antiprotons. Protons are
not rays, of course, but the terminology "cosmic rays" survives
nonetheless. We are, after all, creatures of habit.
The studies of cosmic rays mover! forward! rapidity after
WorIcl War II with the advance of technology (e.g., high
resolution nuclear emulsions en cl sophisticated electronic
cletectors). Over the course of his career Meyer clesignec!
many innovative instruments to explore the energy clistri-
butions of both the major en cl minor components among
the cosmic-ray particles.
Simpson recognized that time variations of the cosmic-
ray intensity, often correlating with solar activity, were
somehow a consequence of conditions in space. Lacking
spacecraft in those days to carry instruments into space for
a direct look, he sought to use the cosmic-ray variations as a
probe of those conditions. The iclea was to obtain quantita-
tive measurements of the clepenclence of the time variations
on the energy of the protons, so that various speculations
on electric fielcis in space or mollifications of the geomagnetic
fielcl or, whatever, couIcl be tested en cl confirmed or rulecl
out. Thus, besides the five neutron monitor stations set up
by Simpson at geomagnetic latitucles from 0° to 60°, Simpson
and Meyer exploited the magnetic field of Earth as a
spectrometer with extensive north-south flights with neu-
tron monitors, etc., in aircraft supplier! by the U.S. Air Force.
They also launchecl many balloon-borne instruments to the
upper atmosphere (~100,000 ft) to connect the ground mea-
surements of the cosmic-ray intensity to the intensity at the
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PETER MEYER
145
top of the atmosphere. The gigantic cosmic-ray flare on the
Sun on February 23, 1956, was a lucky event in this respect,
showing the direct arrival of energetic protons from the
Sun, follower! by a slow clecTine, indicating that the inner
Solar System is open out to about the orbit of Mars en cl
enclosecl by magnetic fielcis beyond (1956~. Together with
the energy clepenclence of the ciay-by-ciay time variations
inferred from the neutron monitor stations, it became clear
that the variations of the cosmic rays couIcl be a conse-
quence only of time-varying magnetic fielcis in interplan-
etary space, implying that space was Flee with plasma (ion-
ized gas) strongly influenced by solar activity (1959~.
They shower! that the occasional abrupt Forbush decrease
in the cosmic-ray intensity, cliscoverecl by Forbush with ioniza-
tion chambers some years earlier, extenclecl to energies of
20-30 GeV en c! conic! be unclerstooc! only in terms of broac!
domains of magnetic fielcl in interplanetary space. These
revelations set the intellectual stage for the construction of
the theoretical solar wine! concept in ~ 958.
The space age was beginning at about this time, en cl
Meyer colIaboratecl with Simpson in studies of the outer
Van Allen racliation belt. The outer belt is fee! by fast par-
ticles from the Sun en cl by the clecay of neutrons proclucecl
by the cosmic-ray proton bombardment of the terrestrial
atmosphere. The distribution of the trapped particles is con-
tinually moclifiecl by diffusive losses en cl by azimuthal drift
of the particles in the active geomagnetic fielcI. The structure
en c! behavior of the outer racliation belt was a challenge to
experimentalists en cl theoreticians alike. The studies carried
out by Simpson en cl Meyer (1961) showocl that electrons
were sometimes accelerates! in place, and, cluring times of
large variations in the outer magnetosphere, the particles
were carried with the clisplacecl magnetic fielcI.
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B I O G RA P H I C A L
EMOIRS
While this work was going on, Meyer was thinking about
the still uncletectecl electron component of the cosmic rays,
estimated to make up perhaps one in a huncirecl of the
cosmic-ray particles at any given particle energy. The cletec-
tion of these rare relativistic electrons among the numerous
protons was quite a challenge to the ingenuity of the
experimentaTist for two reasons. First, an occasional proton
produces a signal in the detector that mimics the signature
of an electron, en cl second, it must be ascertained that a
cletectec! electron comes from somewhere out in space en c!
is not proclucecl as a secondary particle in the upper atmo-
sphere. Thus, a sophisticated detector system is required
en c! must be flown at high altitucle on stratospheric balloons.
The successful electron detection was reported by two
teams just a couple of weeks apart. First, lames Earl of the
University of Minnesota succeeded by visualizing the char-
acteristic showers generated by electrons
in a multiplate
cloucl chamber flown on balloons. Peter Meyer with his
graduate student Rochus Vogt clevelopec! a purely electronic
detector system. The range of the electron shower, en cl
hence the electron energy, was measured in a sandwich of
alternating layers of leac! en c! plastic scintillators, backwarcI-
moving particles, or interacting protons that couIcl simu-
late shower signals, were excluded by analyzing the signals
in two Nat scintillators above and below the sandwich. The
contribution of secondary electrons generated in the atmo-
sphere couIcl be cleterminecl as the instrument ascenclecl
toward! the top of the atmosphere. One wouic! expect that
the intensity of downward-moving secondary electrons would
clecline in proportion to the cleclining air mass overhead.
However, the measurer! electron intensity reacher! a con-
stant value before the balloon approached its maximum
altitucle, with only 3-5 g/cm2 of air left overhead. This clearly
indicated a flux of cosmic-ray electrons arriving from space.
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PETER MEYER
147
Meyer en c! Vogt measurer! 4 x ~o-3 incoming electrons/
cm2sec sr in the energy range ~ 00-] 000 MeV ~ ~ 961 ), to be
compared with about 300 x 10-3 protons/cm sec sr in the
same energy range. So there was incleec! an electron com-
ponent of the cosmic rays, of the same general magnitude
as estimated from the observed non thermal syn chro tron
radio emission from the Galaxy.
Meyer en cl Vogt were able to show how the electrons
variecl through a Forbush decrease (1961), receiving the
same moclulation as the cosmic-ray protons, thereby show-
ing that the electrons originated outside the Solar System.
They were soon able to identify the temporary increases of
energetic electrons proclucec! by solar flares (1962~.
The next step after the measurements of the cosmic-ray
electrons was the question of the cosmic-ray positrons (the
anti-electrons) among the cosmic rays. Cosmic-ray electrons
en cl positrons must be proclucecl throughout the Galaxy in
about equal numbers by the occasional collision of high-
energy protons with the nuclei of atoms in interstellar space.
In fact, for positrons this secondary process must be the
predominant procluction mechanism, while electrons might
also be accelerates! from a sample of "ordinary matter," just
like the protons en cl other nuclei. Thus it wouIcl be inter-
esting to measure the abundance of positrons relative to
electrons. Again the experimental clifficulties are that the
positron intensity is much smaller than the protons, en cl
positrons are proclucecl in great numbers by the proton
collisions with the nuclei of the atmosphere en c! collisions
with the instrument itself. After the electron studies were
well in hand Roger Hilclebrancl relatecl how Meyer askocl
him one day what he thought it might take to distinguish
the positrons. Hilclebrancl repliecl that it wouIcl require a
whole physics laboratory to go up with a balloon to the top
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48
B I O G RA P H I C A L
EMOIRS
of the atmosphere. Meyer smiler! en c! saicI, "Why clon't we
give it a try?"
Positrons differ from electrons in their opposite electric
charge, of course, so the electron-positron separation conic!
be accomplishecl with a suitable magnetic fielcI. Meyer en cl
Hilclebrancl clevelope cl a sophisticate cl in strumen t much along
the lines of the electron detector but with a strong mag-
netic fielcl between the poles of a permanent magnet, through
which the particles hacl to pass if they were to be recorclecI.
The electrons were cleflectec! one way by the magnetic field!
en cl the positrons the other. They usecl spark chambers
insteacl of Nat scintilIators, en cl the system was again enclosecl
in guarc! counters so as to be sensitive only to particles
from above. The Meyer-Hilclebrancl collaboration lecl to a
clean separation en cl measurement of the positrons en cl
electrons as a function of energy (1965~. Very roughly, they
founcl that there were far fewer positrons (~10-~) than elec-
trons over the energy range 40-3000 MeV. As the positrons
are produced by collisions of cosmic-ray protons with the
nuclei of the ambient interstellar gas, their relative number
provides a measure of the amount of matter through which
the cosmic-ray protons have passed while being accelerated
in their sources en cl subsequently in their passage through
interstellar space before arriving at the Solar System. The
surplus of electrons over positrons shows that there must
be cosmic accelerators that produce the electrons clirectly,
perhaps together with the protons en cl nuclei that consti-
tute the majority of the cosmic rays.
The next few years were devoted to improving the systems
detecting the electrons en cl positrons, with an eye to obtaining
the combiner! energy spectrum of electrons en c! positrons
up to several hundred GeV. Gas Cerenkov counters and
time-of-flight measurement techniques were introclucecl to
reject background! protons en c! were combiner! with mas-
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PETER MEYER
149
sive shower counters to analyze the electron cascade in cle-
tail. The instruments were calibratecl at laboratory accelera-
tors (e.g., at the Stanford Linear Accelerator Center) ~ ~ 968,
1972, 1973, 1974, 1976~.
Meyer acivancecl the particle detection technology to clo
a number of other measurements. One interesting episode
was the detection of the electrons from the Jupiter electron
beacon. Simpson et al. en cl Teegarten et al. hacl found,
from particle detectors carried on spacecraft out to the gen-
eral vicinity of Jupiter, that Jupiter emits a powerful burst
of relativistic electrons once each Manhour rotation period.
These electrons can be cletectecl at distances up to ~ AU or
more en c! can be iclentifiec! by their precise period! of re-
currence. Jupiter orbits the Sun at a distance of 5 AU, en cl
the electrons clash from Jupiter along the spiral magnetic
field! in interplanetary space. Working with Jacques L'Heureux
en cl using the electron detector on the OGO-5 spacecraft,
they founcl that when Earth was passing through the spiral
magnetic lines of force connecting out to Jupiter, Earth was
bathed in the electrons from the Jupiter beacon, no longer
clearly pulsing but occurring only when the fielcl connects
Earth to Jupiter.
At the same time Meyer and Dietrich Muller became
interested in the composition of cosmic-ray nuclei at high
energies. With graduate student E. JuTiusson they clesignec!
a new detector system to measure the abundances of heavy
nuclei at energies above ~ 0 GeV/nucleon ~ ~ 972, ~ 974, ~ 975,
1978~. The essential point is that cosmic rays presumably
consist of ordinary matter in an ionized state when the
matter is caught up in the acceleration process en cl the
incliviclual particles are huriec! away at nearly the speec! of
light. Thus, determining the precise relative abundances of
the different elements among the cosmic rays tells us some-
thing about where the cosmic rays were accelerated. As had
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B I O G RA P H I C A L
EMOIRS
aireacly been observer! at Tower energy, they fount! the rela-
tive abundances of the nuclei to be more or less along the
lines of the stanciarcl cosmic abundances cleterminecl from
meteorites, etc. except for such nuclei as Li, Be, en c! B.
These nuclei are rare in the general cosmos because they
are burned up quickly in stellar interiors.
Most of the matter in the Galaxy (inclucling ourselves)
has been processed through one or more massive stars, as
inclicatecl by the general presence of the heavier nuclei C,
N. O et al. synthesizer! in the late stages of evolution of the
incliviclual massive star. Thus when the matter is clispersecl
by the supernova explosion at the end of the short life of
the massive star, the matter is sent on its way with C, N. O.
etc., but very little if any 2H, 3He, Li, Be, en cl B. On the
other hand it was founcl that cosmic rays contain substan-
tial amounts of these otherwise rare nuclei. The explana-
tion is that these nuclei are spalIation products (i.e., chunks
of heavier nuclei C, N. etc., among the cosmic rays knockocl
off by a collision with the nucleus of an atom or ion of the
interstellar gas). On this basis one couIcl determine that
the cosmic rays have passed through about 7 gm/cm2 of
interstellar matter. The discovery by Meyer en c! colleagues
was that the Li, Be, en cl B became less abundant with in-
creasing energy above about 10 GeV/nucleon. This incli-
cates a shorter path length and consequently shorter life in
the Galaxy with increasing energy of the heavy cosmic-ray
nuclei. It shows that the cosmic rays are not graclually accel-
eratec! by reflections from the magnetic fielcis of moving
interstellar gas cloucis. The graclual acceleration was origi-
nally suggested by Fermi as a possible origin of the cosmic
rays. The gradual acceleration predicts that the particle en-
ergy increases with the time spent in the Galaxy. Insteacl
the measurements require that the cosmic rays be acceler-
ated to their final energies in some initial short-lived event
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PETER MEYER
151
(e.g., a supernova explosion or supernova remnant). The
more energetic cosmic-ray particles seem to be able to es-
cape sooner from the magnetic fielcis of the Galaxy, so they
generate fewer spallation nuclei.
Meyer en cl {uliusson subsequently extenclecl the measure-
ments beyond Fe, covering atomic numbers up to 36, the
very heavy nuclei (1975~. They fount! the relative abundances
among the very heavy cosmic-ray nuclei to parallel the normal
cosmic abundances, further supporting the iclea that the
cosmic rays originates! from ordinary cosmic matter that
just happened to be hit by an explocling supernova or other
catastrophe.
One of the more exciting results in the next few years
was the direct observation of the particles acceleratecl by
shocks in interplanetary space created by an outburst asso-
ciatec! with a solar flare. (We wouic! recognize the shock
tociay as the result of a coronal mass ejection at about the
same time as the flare.) A flare often produces a burst of
fast particles, sometimes called solar cosmic rays, although
their numbers diminish more rapidly with increasing energy
than the true galactic cosmic-ray particles, en cl the relative
abundances of the nuclei show a strong enhancement of
elements with low first ionization potential. Meyer, assisted
by Paul Evenson en cl S. Yanagita, founcl a population of
nuclei accelerates! in interplanetary space within the shock
wave from an explosive event on the Sun (1982~. A little
later acceleratecl electrons were founcl as well (1985~. The
measurements clemonstratec! again the remarkable efficiency
of nature to accelerate nuclei to high energy. Nothing more
than the common shock front is neeclecI. Incleecl it is now
believer! that the shock front is probably the universal particle
acceleration mechanism, because little else shows promise
for converting so large a fraction of the bulk kinetic energy
into fast particles.
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B I O G RA P H I C A L
EMOIRS
Another result was the detection of the energetic protons
proclucecl by the clecay of neutrons created by flares on the
Sun. The vigorous acceleration of nuclei (mostly protons)
to high energy in flares bombards the Sun en c! provides
many nuclear reactions in the solar atmosphere below the
flare, emitting gamma rays en cl neutrons, etc. The gamma
rays can be observer! clirectly, of course. The neutrons, equally
free to escape from the magnetic fielcis of the flare, clo not
get as far as Earth (S light minutes from the Sun) because
their speecis are only about a tenth of the speec! of light
en cl they enjoy only a 15-minute half-life. They clecay into
protons of the same kinetic energy, which then channel
along the spiral interplanetary magnetic field and can be
cletectecl whenever a suitable particle detector meets that
spiral. Detection at Earth requires only that the neutron
have a direct spiral line of communication to Earth at the
time it decays, perhaps having come from a flare on the
back sicle of the Sun ~ ~ 983, ~ 984, ~ 990) .
Inasmuch as cosmic rays are observer! to extent! up to
energies above lode eV/nucleon (from unknown sources)
it was clearly clesirable to extend the work on the relative
abundances of the cosmic-ray nuclei to above the 100 GeV/
nucleon region achieved in the work aIreacly citecI. How-
ever that extension required new technology. The number
of cosmic-ray particles in a given energy interval declines
with increasing particle energy E approximately as E-n with
n lying somewhere in the interval 2.7 to about 3, clepencI-
ing upon E. It is obvious then that to go to higher energies
means far fewer particles among the general background of
cosmic rays. That is to say, the background "noise" becomes
deafening. Meyer with Muller en c! others came up with the
iclea of looking for very energetic nuclei using the transi-
tion racliation proclucecl as the nuclei pass from air into a
transparent solic! en c! from the solic! into air. The transition
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PETER MEYER
153
racliation is very weak but increases rapidity as the speec! of
the particle approaches the speed of light. Thus an instru-
ment detecting the passage of energetic nuclei by their tran-
sition racliation facles out for particles below about 100 GeV/
nucleon (traveling at a speecl of 0.99995c, where c is the
speecl of light). That is to say, a transition racliation cletec-
tor wouic! be clear to most of the background! noise, but it
wouIcl begin to respond to nuclei of 100 GeV/nucleon or
more. Even so, the instrument wouIcl have to be large, to
intercept enough of the very-high-energy particles en c! then
to pass the particles through enough air-plastic interfaces
to get a detectable signal.
The result was the "Chicago Egg," which was flown on
Spacelab 2 on the space shuttle. Designed and built by Meyer
en cl Muller, the Egg was 9 feet in diameter en cl 12 feet
high. The instrument was encloses! in a welclec! aluminum
tank: the shell of the egg. Insicle the shell the instrument
consisted of scintillation counters, to define en cl clelimit
the paths of the cosmic rays that it recorclecI. The heart of
the instrument was the large volume of commercial polyolefin
fiber forming the transition radiation generator. The essential
aspect of the generator was that the individual high-energy
cosmic-ray particle shouIcl pass through many air-plastic inter-
faces, producing transition racliation at each interface, en cl
that the transition racliation not be absorber! by the plastic
fibers. The transition racliation was soft X rays en cl was
detected in xenon-fi~led proportional chambers interspersed
between layers of fiber material. The whole thing weighed
2.5 tons en cl cost about $10 million. The size was limitecl by
the cargo bay of the shuttle, and the Chicago Egg flew on
the Challenger in 1985 for several clays' exposure to the
cosmic rays. During that time it acquired the most cletailecl
ciata ever obtained on the composition of cosmic rays at
extreme energies ~ ~ 98S, ~ 99 ~ ~ .
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B I O G RA P H I C A L
EMOIRS
Briefly, the Chicago Egg recorclec! the atomic number
en cl energy of nuclei above 150 GeV/nucleon basecl on
their transition racliation. The measurements faclecl out at
high energies of several thousand! GeV because of the
cleclining number of cosmic rays at increasing energies. Nuclei
in the lower energy range 40-400 GeV/nucleon were cletectecl
en c! sizer! with gas Cerenkov counters. The results of this
investigation showocl that the relative abundances of the
secondary nuclei (e.g., the abundance ratio B/C) continu-
ally decreases up to very high energies. This can be uncler-
stood with the assumption of an energy spectrum E-2 ~ pro-
clucecl in the unknown cosmic-ray source, as is preclictecl
for shock acceleration processes, follower! by more rapic!
escape from the Galaxy with increasing E. As was aIreacly
known at lower energies, the ciata indicate the enhanced
abundance of nuclei with Tow first ionization potential, much
as one fincis for energetic nuclei from solar flares, etc. De-
tailecl comparisons with the relative abundances of cosmic-
ray nuclei at Tower energies begins to give a picture of the
conditions uncler which cosmic rays are created in their
various sources.
There are numerous other investigations that Meyer
accomplishecl along with the major achievements summa-
rizecl here. In aciclition to the ambitious scientific program
that market! his career he took on many responsibilities at
the University of Chicago en cl in national en cl international
scientific organizations. For instance, he was chair of the
Cosmic Ray Physics Division of the American Physical Society,
1972-73. He was a member of the Space Science Board of
the National Academy of Sciences, 1975-78 en cl served as
chair of the Committee on Astronomy and Astrophysics of
the Space Science Board, 1975-77. He served as director of
the Enrico Fermi Institute at the University of Chicago,
1978-82. He was then chair of the Department of Physics,
OCR for page 155
PETER MEYER
155
1986-89. These responsibilities all involve consiclerable time
en cl energy, but he hancIlecl them in some of his scientifi-
cally most productive years. His commitment to uncler-
gracluate teaching was recognizes! in 1971 by the Llewellyn
John en cl Harriet Manchester Quantrell Awarcl for Excel-
lence in Unclergracluate Teaching.
Meyer's scientific productivity was also recognizes! in the
lancl of his birth, where he became a foreign member of
Germany's Max Planck Society en cl the Max Planck Insti-
tute for Physics en c! Astrophysics in Munchen in 1973. In
1984 he was a recipient of the Alexancler Von HumboIcit
Awarcl for Senior Unitecl States Scientists.
He was electec! a member of the National Academy of
Sciences in 1989 in recognition of his many funciamental
contributions to present unclerstancling of the fast particles
(cosmic rays) that come from everywhere, near en c! far, in
the active universe. He leaves behind a scientific legacy en cl
the foncl memories of his many colleagues. He is survivecl
by his seconc! wife, the renowned! microbiologist Patricia
Spear, who is chair of microbiology-microimmunology at
the Northwestern University Meclical School, by his two sons,
Stephan Meyer, professor of astronomy en c! astrophysics at
the University of Chicago, and Andreas Meyer of Portsmouth,
New Hampshire, en cl by two grancichilciren, Samantha Meyer
en c! Niels Meyer of Chicago.
THE AUTHOR RECEIVED important comments and suggestions in the
construction of this biographical memoir from Rochus Vogt, Dietrich
Muller, and Patricia Spear.
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156
B I O G RA P H I C A L
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SELECTED BIBLIOGRAPHY
1949
The (y,n)-reaction on deuterium and the binding energy of the
deuteron. Z. Phys. 126:336.
1950
With A. P. French and P. B. Treacy. oc-particles from Fi9 bombarded
by deuterons. Proc. R. Soc. A 63:666.
1956
With E. N. Parker and J. A. Simpson. Solar cosmic rays of February
1956 and their propagation through interplanetary space. Phys.
Rev. 104:768.
1959
Primary cosmic-ray proton and alpha-particle intensities and their
variation with time. Phys. Rev. 115:6.
1961
With C. Y. Fan and J. A. Simpson. Dynamics and structure of the
outer radiation belt. 7. Geophys. Res. 66:2607.
With R. Vogt. Electrons in the primary cosmic radiation. Phys. Rev.
Lett. 6:193.
With R. Vogt. The primary cosmic electron flux during a Forbush-
type decrease. 7. Geophys. Res. 66:3950.
1962
With R. Vogt. High energy electrons of solar origin. Phys. Rev. Lett.
8:387.
1965
With R. C. Hartmann and R. H. Hildebrand. Observation of the
cosmic ray electron-positron ratio from 100 MeV to 3 BeV in
1964. 7. Geophys. Res. 70:2713.
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PETER MEYER
1968
157
With J. L'Heureux. The primary cosmic ray electron spectrum in
the energy range 300 MeV to 4 BeV from 1964 to 1966. Canad. f.
Phys. 46:S892.
1972
With J. L'Heureux and C. Y. Fan. The quiet time spectra of cosmic
ray electrons of energies between 10 and 200 MeV observed on
OGO-5. Astrophys. f. 171:363.
With E. Juliusson and D. Muller. Composition of cosmic ray nuclei
at high energies. Phys. Rev. Lett. 29:445.
1973
With D. Muller. The spectrum of galactic electrons with energies
between 10 and 900 GeV. Astrophys. f. 186:841.
1974
Composition and spectra of primary cosmic ray electrons and nuclei
above 101° eV. Photos. Trans. R. So c. Lond. A 277:349.
1975
With E. Juliusson. A measurement of abundances of WH-nuclei
above 0.6 GeV/nucleon. Astrophys. f. 201: 76.
1976
With J. L'Heureux. Quiet time increases of low energy electrons:
The Jovian origin. Astrophys. J. 209:955.
1978
The cosmic ray isotopes. Nature 272:675.
1982
With P. Evenson and S. Yanagita. Solar flare shocks in interplanetary
space and solar particle events. 7. Geophys. Res. 87:625.
1983
With P. Evenson and K. R. Kyle. Protons from the decay of solar
flare neutrons. Astrophys. f. 274:875.
OCR for page 158
158
B I O G RA P H I C A L
1984
EMOIRS
With P. Evenson, D. J. Forrest, and S. Yanagita. Electron-rich par-
ticle events and the production of gamma rays by solar flares.
Astrophys. J. 283:439.
1985
With S. R. Kane and P. Evenson. Acceleration of interplanetary
solar electrons in the 1982 August 14 flare. Astrophys. f. Lett. 299:L107.
With G. E. Morfill and R. Lust. Cosmic ray nuclei and the structure
of the Galaxy. Astrophys. f. 296:670.
1988
With J. M. Grunsfeld, J. L'Heureux, D. Muller, and S. P. Swordy.
Energy spectra of cosmic ray nuclei from 50 to 2000 GeV per
emu. Astrophys. f. Lett. 327:L31.
1990
With P. Evenson, R. Krooger, and D. Reames. Solar neutron decay
proton observations in cycle 21. Astrophys. f. 73~Suppl.~:273.
1991
With D. Muller, S. P. Swordy, J. L'Heureux, and J. M. Grunsfeld.
Energy spectra and composition of primary cosmic rays. Astrophys.
J. 374:356.
OCR for page 159
Representative terms from entire chapter:
peter meyer
