Emilio Picasso (9 July 1927, in

Genoa Genoa ( ; ; ) is a city in and the capital of the Italian region of Liguria, and the sixth-largest city in Italy. As of 2025, 563,947 people live within the city's administrative limits. While its metropolitan city has 818,651 inhabitan ...

– 12 October 2014) was an Italian

physicist A physicist is a scientist who specializes in the field of physics, which encompasses the interactions of matter and energy at all length and time scales in the physical universe. Physicists generally are interested in the root or ultimate cau ...

. For most of his career, he served as a researcher at

CERN The European Organization for Nuclear Research, known as CERN (; ; ), is an intergovernmental organization that operates the largest particle physics laboratory in the world. Established in 1954, it is based in Meyrin, western suburb of Gene ...

and was project leader for the

Large Electron-Positron Collider Large means of great size. Large may also refer to: Mathematics * Arbitrarily large, a phrase in mathematics * Large cardinal, a property of certain transfinite numbers * Large category, a category with a proper class of objects and morphisms (or ...

(LEP), one of the largest

particle accelerator A particle accelerator is a machine that uses electromagnetic fields to propel electric charge, charged particles to very high speeds and energies to contain them in well-defined particle beam, beams. Small accelerators are used for fundamental ...

s ever constructed. Picasso was awarded the

Legion of Honour The National Order of the Legion of Honour ( ), formerly the Imperial Order of the Legion of Honour (), is the highest and most prestigious French national order of merit, both military and Civil society, civil. Currently consisting of five cl ...

from France and is also bearer of the Knight Grand Cross of the Italian Republic, Italy's highest civilian honor. When he passed, his hometown newspaper called it a moment of mourning for "the international scientific community and for Pisa."

Life and career

Picasso studied first

mathematics Mathematics is a field of study that discovers and organizes methods, Mathematical theory, theories and theorems that are developed and Mathematical proof, proved for the needs of empirical sciences and mathematics itself. There are many ar ...

and then two years

physics Physics is the scientific study of matter, its Elementary particle, fundamental constituents, its motion and behavior through space and time, and the related entities of energy and force. "Physical science is that department of knowledge whi ...

at the

University of Genoa The University of Genoa () is a public research university. It is one of the largest universities in Italy and it is located in the city of Genoa, on the Italian Riviera in the Liguria region of northwestern Italy. The original university was fou ...

. After his

doctorate A doctorate (from Latin ''doctor'', meaning "teacher") or doctoral degree is a postgraduate academic degree awarded by universities and some other educational institutions, derived from the ancient formalism '' licentia docendi'' ("licence to teach ...

, he started working there as an assistance

professor Professor (commonly abbreviated as Prof.) is an Academy, academic rank at university, universities and other tertiary education, post-secondary education and research institutions in most countries. Literally, ''professor'' derives from Latin ...

for

experimental physics Experimental physics is the category of disciplines and sub-disciplines in the field of physics that are concerned with the observation of physical phenomena and experiments. Methods vary from discipline to discipline, from simple experiments and o ...

. At the beginning he kept himself busy with

atom physics Atomic physics is the field of physics that studies atoms as an isolated system of electrons and an atomic nucleus. Atomic physics typically refers to the study of atomic structure and the interaction between atoms. It is primarily concerned wit ...

, but then his interests changed to

elementary particle physics Particle physics or high-energy physics is the study of fundamental particles and forces that constitute matter and radiation. The field also studies combinations of elementary particles up to the scale of protons and neutrons, while the stud ...

. Therefore, he worked at the

Betatron A betatron is a type of cyclic particle accelerator for electrons. It consists of a torus-shaped vacuum chamber with an electron source. Circling the torus is an iron transformer core with a wire winding around it. The device functions simil ...

Turin Turin ( , ; ; , then ) is a city and an important business and cultural centre in northern Italy. It is the capital city of Piedmont and of the Metropolitan City of Turin, and was the first Italian capital from 1861 to 1865. The city is main ...

and then at the

Synchrotron A synchrotron is a particular type of cyclic particle accelerator, descended from the cyclotron, in which the accelerating particle beam travels around a fixed closed-loop path. The strength of the magnetic field which bends the particle beam i ...

Frascati Frascati () is a city and in the Metropolitan City of Rome Capital in the Lazio region of central Italy. It is located south-east of Rome, on the Alban Hills close to the ancient city of Tusculum. Frascati is closely associated with science, ...

. In the years 1961/62 he worked in a group led by

Cecil Powell Cecil Frank Powell (5 December 1903 – 9 August 1969) was an English particle physicist who received the Nobel Prize in Physics in 1950 for heading the team that developed the photographic method of studying nuclear processes and for the result ...

, which researched

cosmic rays Cosmic rays or astroparticles are high-energy particles or clusters of particles (primarily represented by protons or atomic nuclei) that move through space at nearly the speed of light. They originate from the Sun, from outside of the Solar ...

with balloons. Two years later in 1964 he joined

for researching the

anomalous magnetic moment In quantum electrodynamics, the anomalous magnetic moment of a particle is a contribution of effects of quantum mechanics, expressed by Feynman diagrams with loops, to the magnetic moment of that particle. The ''magnetic moment'', also called '' ...

muon A muon ( ; from the Greek letter mu (μ) used to represent it) is an elementary particle similar to the electron, with an electric charge of −1 '' e'' and a spin of ''ħ'', but with a much greater mass. It is classified as a ...

s, which was a precision test for the

quantum electrodynamics In particle physics, quantum electrodynamics (QED) is the Theory of relativity, relativistic quantum field theory of electrodynamics. In essence, it describes how light and matter interact and is the first theory where full agreement between quant ...

. The so-called ''g minus 2'' experiment was an idea of

Leon Lederman Leon, Léon (French) or León (Spanish) may refer to: Places Europe * León, Spain, capital city of the Province of León * Province of León, Spain * Kingdom of León, an independent state in the Iberian Peninsula from 910 to 1230 and again fro ...

. Picasso worked in a collaboration with physicists John Bailey, Francis Farley,

Simon van der Meer Simon van der Meer (24 November 19254 March 2011) was a Dutch particle accelerator physicist who shared the Nobel Prize in Physics in 1984 with Carlo Rubbia for contributions to the CERN project which led to the discovery of the W and Z parti ...

, Guido Petrucci and Frank Krienen. At this experiment a 10

GeV In physics, an electronvolt (symbol eV), also written electron-volt and electron volt, is the measure of an amount of kinetic energy gained by a single electron accelerating through an electric potential difference of one volt in vacuum. When us ...

beam of protons is ejected by the

Proton Synchrotron The Proton Synchrotron (PS, sometimes also referred to as CPS) is a particle accelerator at CERN. It is CERN's first synchrotron, beginning its operation in 1959. For a brief period the PS was the world's highest energy particle accelerator. It ...

. This beam is headed on target inside one of the Muon

Storage ring A storage ring is a type of circular particle accelerator in which a continuous or pulsed particle beam may be kept circulating, typically for many hours. Storage of a particular particle depends upon the mass, momentum, and usually the charge o ...

s, which were built for this experiment. There 70% of the

proton A proton is a stable subatomic particle, symbol , Hydron (chemistry), H+, or 1H+ with a positive electric charge of +1 ''e'' (elementary charge). Its mass is slightly less than the mass of a neutron and approximately times the mass of an e ...

s interact with each other producing a burst of particles, among other things many negative

pion In particle physics, a pion (, ) or pi meson, denoted with the Greek alphabet, Greek letter pi (letter), pi (), is any of three subatomic particles: , , and . Each pion consists of a quark and an antiquark and is therefore a meson. Pions are the ...

s. The

s, which have the right momentum (about 1,3

/ c), turn in the

magnetic field A magnetic field (sometimes called B-field) is a physical field that describes the magnetic influence on moving electric charges, electric currents, and magnetic materials. A moving charge in a magnetic field experiences a force perpendicular ...

so that they can orbit the

ring (The) Ring(s) may refer to: * Ring (jewellery), a round band, usually made of metal, worn as ornamental jewelry * To make a sound with a bell, and the sound made by a bell Arts, entertainment, and media Film and TV * ''The Ring'' (franchise), a ...

. There the pions decay rather quickly, in the first turn around one fifth of them change to negative

s. Some of these muons which are emitted at small angles to the direction of the pions have slightly lower momentum than the pions and therefore move to an orbit of smaller radius. So they miss the target at the end of the first turn and are kept orbiting in the magnet ring. The measurement needed 15 years and at the end, they calculated the g-factor and the

magnetic moment In electromagnetism, the magnetic moment or magnetic dipole moment is the combination of strength and orientation of a magnet or other object or system that exerts a magnetic field. The magnetic dipole moment of an object determines the magnitude ...

um of a muon. After that Picasso was concerned with the design of a

superconducting Superconductivity is a set of physical properties observed in superconductors: materials where electrical resistance vanishes and magnetic fields are expelled from the material. Unlike an ordinary metallic conductor, whose resistance decreases g ...

gravitational-wave detector. In the year 1980 the

director-general A director general, general director or director-general (plural: ''directors general'', ''general directors'', ''directors-general'', ''director generals'' or ''director-generals'') is a senior executive officer, often the chief executive officer ...

Herwig Schopper Herwig Franz Schopper (born 28 February 1924) is a German experimental physicist. He was the director general of CERN from 1981 to 1988. Biography Schopper was born in Lanškroun, Czechoslovakia, to a family of Austrian descent. He obtained hi ...

announced him to be the project leader of the LEP at the CERN. Here he could use his knowledge about

superconductors Superconductivity is a set of physical properties observed in superconductors: materials where electrical resistance vanishes and magnetic fields are expelled from the material. Unlike an ordinary metallic conductor, whose resistance decreases ...

. At the beginning they planned a bigger ring, which should go 12 km under the

Jura Mountains The Jura Mountains ( ) are a sub-alpine mountain range a short distance north of the Western Alps and mainly demarcate a long part of the French–Swiss border. While the Jura range proper (" folded Jura", ) is located in France and Switzerla ...

. But because of the high water pressure, the tunnel expert Giovanni Lombardi disadvised from this layer, so they reduced the way under the

and the collaboration transferred the ring. But also 3 km under the mountains was difficult to build and "the mountains answered" (Picasso), water broke in and they had to reduce the length of the tunnel, because it was not possible to build under the

mountains A mountain is an elevated portion of the Earth's crust, generally with steep sides that show significant exposed bedrock. Although definitions vary, a mountain may differ from a plateau in having a limited summit area, and is usually higher ...

. At the 14 July 1989 the LEP was brought on line like Picasso promised president

Jacques Chirac Jacques René Chirac (, ; ; 29 November 193226 September 2019) was a French politician who served as President of France from 1995 to 2007. He was previously Prime Minister of France from 1974 to 1976 and 1986 to 1988, as well as Mayor of Pari ...

two years ago. In the year 1992, he resigned at CERN and became director at the ''

Scuola Normale Superiore The Scuola Normale Superiore (commonly known in Italy as "la Normale") is a public university in Pisa and Florence, Tuscany, Italy, currently attended by about 600 undergraduate and postgraduate (PhD) students. Together with the University of Pi ...

'' in

Pisa Pisa ( ; ) is a city and ''comune'' (municipality) in Tuscany, Central Italy, straddling the Arno just before it empties into the Ligurian Sea. It is the capital city of the Province of Pisa. Although Pisa is known worldwide for the Leaning Tow ...

, where he continued in collaboration with the

his researches about gravitational-wave detector.

Awards

Picasso was a member of the ''

Académie des sciences The French Academy of Sciences (, ) is a learned society, founded in 1666 by Louis XIV at the suggestion of Jean-Baptiste Colbert, to encourage and protect the spirit of French Scientific method, scientific research. It was at the forefron ...

'' and the ''

Accademia Nazionale delle Scienze The Accademia Nazionale delle Scienze (), or more formally L'Accademia Nazionale delle Scienze detta dei XL, and also called the Accademia dei XL (), is Italy's national academy of science. Its offices are located within the Villino Rosso, at the co ...

''. Furthermore, he was bearer of the

and bearer of the Knight Grand Cross of the Italian Republic.

References

External links

Scientific publications of Emilio Picasso
on

INSPIRE-HEP INSPIRE-HEP is an open access digital library for the field of high energy physics (HEP). It is the successor of the Stanford Physics Information Retrieval System (SPIRES) database, the main literature database for high energy physics since the 1 ...

Sources

*Andrew Sessler, Edmund Wilson: ''Engines of discovery.'' World Scientific, 2007. *Francis Farley, Emilio Picasso: ''The Muon g-2 Experiment.'' In: T. Kinoshita (Hrsg.): ''Quantum Electrodynamics.'' World Scientific, 1990, S. 479–559. *Francis Farley, Emilio Picasso: ''The Muon g-2 Experiments.'' In: ''Annual Review Nuclear and Particle Science.'' Band 29, 1979, S. 243–282. {{DEFAULTSORT:Picasso, Emilio 1927 births 2014 deaths People associated with CERN Members of the French Academy of Sciences 20th-century Italian physicists University of Genoa alumni