Bruno Rossi
Encyclopedia
Bruno Benedetto Rossi was a leading Italian
-American
experimental physicist
. He made major contributions to cosmic ray
and particle physics
from 1930 through the 1950s, and pioneered X-ray astronomy
and space plasma
physics in the 1960s.
, Italy
. After receiving the doctorate degree from the University of Bologna
, he began his career in 1928 as assistant at the Physics Institute of the University of Florence
where he made his first discoveries regarding the nature of cosmic rays. In 1932 he was called to the University of Padua
as professor of experimental physics. There, in addition to teaching and research, Rossi planned the new Physics Institute of the University and oversaw its construction. In the fall of 1938 he was expelled from his position as a result of the racial decrees of the fascist
state. Rossi was Jewish and so was his wife, Nora Lombroso (granddaughter of anthropologist, Cesare Lombroso
), so they had to leave Italy and traveled to America with brief stays in Copenhagen
, Denmark
and Manchester
, England
.
They arrived at the University of Chicago
in June 1939 where he was given a temporary position as research associate. Rossi immediately began a series of experiments that yielded the first proof of the decay of a fundamental particle
, the mesotron, now called muon
, and a precise measurement of its mean life at rest. The latter was achieved at Cornell University
where he was appointed associate professor in 1942. During the war Rossi worked first as consultant on radar
development at the Radiation Laboratory of the Massachusetts Institute of Technology
, and then at Los Alamos
as co-director of the Detector Group responsible for development of instrumentation for experiments that supported the development of the atomic bomb
s.
In the fall of 1946 Rossi was appointed professor of physics
at MIT where he established the Cosmic Ray Group to investigate the nature and origins of cosmic rays and the properties of the sub-nuclear particles produced in the interaction of cosmic rays with matter. In the late 1950s, when particle accelerator
experiments had come to dominate experimental particle physics, Rossi turned his attention to exploratory research made possible by the new availability of space vehicles. At MIT he initiated rocket
experiments that pioneered the direct measurements of the interplanetary plasma. As a consultant to American Science and Engineering, Inc. he initiated the rocket experiments that discovered the first extra-solar source of X-ray
s, Scorpius X-1
. Rossi was made Institute Professor
at MIT in 1965.
Among his contributions to the electronic techniques of experimental physics are the inventions of the coincidence circuit
(Florence 1930), the time-to-amplitude converter (Cornell 1942) and the fast ionization chamber (Los Alamos, with H. Staub 1943).
Rossi retired from MIT in 1970. From 1974 to 1980 he taught at the University of Palermo
. In 1990 his autobiography, titled Moments in the Life of a Scientist, was published by Cambridge University Press
. He died at his home in Cambridge, Massachusetts
in 1993.
Italy
Italy , officially the Italian Republic languages]] under the European Charter for Regional or Minority Languages. In each of these, Italy's official name is as follows:;;;;;;;;), is a unitary parliamentary republic in South-Central Europe. To the north it borders France, Switzerland, Austria and...
-American
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
experimental physicist
Experimental physics
Within the field of physics, experimental physics is the category of disciplines and sub-disciplines concerned with the observation of physical phenomena in order to gather data about the universe...
. He made major contributions to cosmic ray
Cosmic ray
Cosmic rays are energetic charged subatomic particles, originating from outer space. They may produce secondary particles that penetrate the Earth's atmosphere and surface. The term ray is historical as cosmic rays were thought to be electromagnetic radiation...
and particle physics
Particle physics
Particle physics is a branch of physics that studies the existence and interactions of particles that are the constituents of what is usually referred to as matter or radiation. In current understanding, particles are excitations of quantum fields and interact following their dynamics...
from 1930 through the 1950s, and pioneered X-ray astronomy
X-ray astronomy
X-ray astronomy is an observational branch of astronomy which deals with the study of X-ray observation and detection from astronomical objects. X-radiation is absorbed by the Earth's atmosphere, so instruments to detect X-rays must be taken to high altitude by balloons, sounding rockets, and...
and space plasma
Plasma (physics)
In physics and chemistry, plasma is a state of matter similar to gas in which a certain portion of the particles are ionized. Heating a gas may ionize its molecules or atoms , thus turning it into a plasma, which contains charged particles: positive ions and negative electrons or ions...
physics in the 1960s.
Biography
Rossi was born in VeniceVenice
Venice is a city in northern Italy which is renowned for the beauty of its setting, its architecture and its artworks. It is the capital of the Veneto region...
, Italy
Italy
Italy , officially the Italian Republic languages]] under the European Charter for Regional or Minority Languages. In each of these, Italy's official name is as follows:;;;;;;;;), is a unitary parliamentary republic in South-Central Europe. To the north it borders France, Switzerland, Austria and...
. After receiving the doctorate degree from the University of Bologna
University of Bologna
The Alma Mater Studiorum - University of Bologna is the oldest continually operating university in the world, the word 'universitas' being first used by this institution at its foundation. The true date of its founding is uncertain, but believed by most accounts to have been 1088...
, he began his career in 1928 as assistant at the Physics Institute of the University of Florence
University of Florence
The University of Florence is a higher study institute in Florence, central Italy. One of the largest and oldest universities in the country, it consists of 12 faculties...
where he made his first discoveries regarding the nature of cosmic rays. In 1932 he was called to the University of Padua
University of Padua
The University of Padua is a premier Italian university located in the city of Padua, Italy. The University of Padua was founded in 1222 as a school of law and was one of the most prominent universities in early modern Europe. It is among the earliest universities of the world and the second...
as professor of experimental physics. There, in addition to teaching and research, Rossi planned the new Physics Institute of the University and oversaw its construction. In the fall of 1938 he was expelled from his position as a result of the racial decrees of the fascist
Fascism
Fascism is a radical authoritarian nationalist political ideology. Fascists seek to rejuvenate their nation based on commitment to the national community as an organic entity, in which individuals are bound together in national identity by suprapersonal connections of ancestry, culture, and blood...
state. Rossi was Jewish and so was his wife, Nora Lombroso (granddaughter of anthropologist, Cesare Lombroso
Cesare Lombroso
Cesare Lombroso, born Ezechia Marco Lombroso was an Italian criminologist and founder of the Italian School of Positivist Criminology. Lombroso rejected the established Classical School, which held that crime was a characteristic trait of human nature...
), so they had to leave Italy and traveled to America with brief stays in Copenhagen
Copenhagen
Copenhagen is the capital and largest city of Denmark, with an urban population of 1,199,224 and a metropolitan population of 1,930,260 . With the completion of the transnational Øresund Bridge in 2000, Copenhagen has become the centre of the increasingly integrating Øresund Region...
, Denmark
Denmark
Denmark is a Scandinavian country in Northern Europe. The countries of Denmark and Greenland, as well as the Faroe Islands, constitute the Kingdom of Denmark . It is the southernmost of the Nordic countries, southwest of Sweden and south of Norway, and bordered to the south by Germany. Denmark...
and Manchester
Manchester
Manchester is a city and metropolitan borough in Greater Manchester, England. According to the Office for National Statistics, the 2010 mid-year population estimate for Manchester was 498,800. Manchester lies within one of the UK's largest metropolitan areas, the metropolitan county of Greater...
, England
England
England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...
.
They arrived at the University of Chicago
University of Chicago
The University of Chicago is a private research university in Chicago, Illinois, USA. It was founded by the American Baptist Education Society with a donation from oil magnate and philanthropist John D. Rockefeller and incorporated in 1890...
in June 1939 where he was given a temporary position as research associate. Rossi immediately began a series of experiments that yielded the first proof of the decay of a fundamental particle
Elementary particle
In particle physics, an elementary particle or fundamental particle is a particle not known to have substructure; that is, it is not known to be made up of smaller particles. If an elementary particle truly has no substructure, then it is one of the basic building blocks of the universe from which...
, the mesotron, now called muon
Muon
The muon |mu]] used to represent it) is an elementary particle similar to the electron, with a unitary negative electric charge and a spin of ½. Together with the electron, the tau, and the three neutrinos, it is classified as a lepton...
, and a precise measurement of its mean life at rest. The latter was achieved at Cornell University
Cornell University
Cornell University is an Ivy League university located in Ithaca, New York, United States. It is a private land-grant university, receiving annual funding from the State of New York for certain educational missions...
where he was appointed associate professor in 1942. During the war Rossi worked first as consultant on radar
Radar
Radar is an object-detection system which uses radio waves to determine the range, altitude, direction, or speed of objects. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, weather formations, and terrain. The radar dish or antenna transmits pulses of radio...
development at the Radiation Laboratory of the Massachusetts Institute of Technology
Massachusetts Institute of Technology
The Massachusetts Institute of Technology is a private research university located in Cambridge, Massachusetts. MIT has five schools and one college, containing a total of 32 academic departments, with a strong emphasis on scientific and technological education and research.Founded in 1861 in...
, and then at Los Alamos
Los Alamos National Laboratory
Los Alamos National Laboratory is a United States Department of Energy national laboratory, managed and operated by Los Alamos National Security , located in Los Alamos, New Mexico...
as co-director of the Detector Group responsible for development of instrumentation for experiments that supported the development of the atomic bomb
Nuclear weapon
A nuclear weapon is an explosive device that derives its destructive force from nuclear reactions, either fission or a combination of fission and fusion. Both reactions release vast quantities of energy from relatively small amounts of matter. The first fission bomb test released the same amount...
s.
In the fall of 1946 Rossi was appointed professor of physics
Physics
Physics is a natural science that involves the study of matter and its motion through spacetime, along with related concepts such as energy and force. More broadly, it is the general analysis of nature, conducted in order to understand how the universe behaves.Physics is one of the oldest academic...
at MIT where he established the Cosmic Ray Group to investigate the nature and origins of cosmic rays and the properties of the sub-nuclear particles produced in the interaction of cosmic rays with matter. In the late 1950s, when particle accelerator
Particle accelerator
A particle accelerator is a device that uses electromagnetic fields to propel charged particles to high speeds and to contain them in well-defined beams. An ordinary CRT television set is a simple form of accelerator. There are two basic types: electrostatic and oscillating field accelerators.In...
experiments had come to dominate experimental particle physics, Rossi turned his attention to exploratory research made possible by the new availability of space vehicles. At MIT he initiated rocket
Rocket
A rocket is a missile, spacecraft, aircraft or other vehicle which obtains thrust from a rocket engine. In all rockets, the exhaust is formed entirely from propellants carried within the rocket before use. Rocket engines work by action and reaction...
experiments that pioneered the direct measurements of the interplanetary plasma. As a consultant to American Science and Engineering, Inc. he initiated the rocket experiments that discovered the first extra-solar source of X-ray
X-ray
X-radiation is a form of electromagnetic radiation. X-rays have a wavelength in the range of 0.01 to 10 nanometers, corresponding to frequencies in the range 30 petahertz to 30 exahertz and energies in the range 120 eV to 120 keV. They are shorter in wavelength than UV rays and longer than gamma...
s, Scorpius X-1
Scorpius X-1
Scorpius X-1 is an X-ray source located roughly 9000 light years away in the constellation Scorpius. Scorpius X-1 was the first extrasolar X-ray source discovered, and, aside from the Sun, it is the strongest source of X-rays in the sky...
. Rossi was made Institute Professor
Institute Professor
Institute Professor is the highest title that can be awarded to a faculty member at the Massachusetts Institute of Technology, a research university located in Cambridge, Massachusetts, United States...
at MIT in 1965.
Among his contributions to the electronic techniques of experimental physics are the inventions of the coincidence circuit
Coincidence circuit
In physics, a coincidence circuit is an electronic device with one output and two inputs. The output is activated only when signals are received within a time window accepted as at the same time and in parallel at both inputs...
(Florence 1930), the time-to-amplitude converter (Cornell 1942) and the fast ionization chamber (Los Alamos, with H. Staub 1943).
Rossi retired from MIT in 1970. From 1974 to 1980 he taught at the University of Palermo
University of Palermo
The University of Palermo is a university located in Palermo, Italy, and founded in 1806. It is organized in 12 Faculties.-History:The University of Palermo was officially founded in 1806, although its earliest roots date back to 1498 when medicine and law were taught there...
. In 1990 his autobiography, titled Moments in the Life of a Scientist, was published by Cambridge University Press
Cambridge University Press
Cambridge University Press is the publishing business of the University of Cambridge. Granted letters patent by Henry VIII in 1534, it is the world's oldest publishing house, and the second largest university press in the world...
. He died at his home in Cambridge, Massachusetts
Cambridge, Massachusetts
Cambridge is a city in Middlesex County, Massachusetts, United States, in the Greater Boston area. It was named in honor of the University of Cambridge in England, an important center of the Puritan theology embraced by the town's founders. Cambridge is home to two of the world's most prominent...
in 1993.
Awards
- Wolf Prize in PhysicsWolf Prize in PhysicsThe Wolf Prize in Physics is awarded once a year by the Wolf Foundation in Israel. It is one of the six Wolf Prizes established by the Foundation and awarded since 1978; the others are in Agriculture, Chemistry, Mathematics, Medicine and Arts. The Prize is often considered the most prestigious...
for his role in the development of X-ray astronomy (1987) - National Medal of ScienceNational Medal of ScienceThe National Medal of Science is an honor bestowed by the President of the United States to individuals in science and engineering who have made important contributions to the advancement of knowledge in the fields of behavioral and social sciences, biology, chemistry, engineering, mathematics and...
(1983) - Rumford PrizeRumford PrizeFounded in 1796, the Rumford Prize, awarded by the American Academy of Arts and Sciences, is one of the oldest scientific prizes in the United States. The prize recognizes contributions by scientists to the fields of heat and light...
award of the American Academy of Arts and SciencesAmerican Academy of Arts and SciencesThe American Academy of Arts and Sciences is an independent policy research center that conducts multidisciplinary studies of complex and emerging problems. The Academy’s elected members are leaders in the academic disciplines, the arts, business, and public affairs.James Bowdoin, John Adams, and...
for "discoveries concerning the nature and origins of cosmic radiations" (1976) - Elliott Cresson MedalElliott Cresson MedalThe Elliott Cresson Medal, also known as the Elliott Cresson Gold Medal, was the highest award given by the Franklin Institute. The award was established by Elliott Cresson, life member of the Franklin Institute, with $1,000 granted in 1848...
(1974) - Gold Medal of the Italian Physical SocietyItalian Physical SocietyThe Italian Physical Society was founded in 1897 and is a non-profit organization whose aim is to promote, encourage, protect the study and the progress of physics in Italy and in the world....
(1970) - Doctors honoris causa from the universities of Palermo, Durham, and Chicago
Legacy
- Rossi X-ray Timing ExplorerRossi X-ray Timing ExplorerThe Rossi X-ray Timing Explorer is a satellite that observes the time structure of astronomical X-ray sources. The RXTE has three instruments—the Proportional Counter Array, the High-Energy X-ray Timing Experiment , and one instrument called the All Sky Monitor...
, a NASANASAThe National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...
satellite X-ray observatory - Bruno Rossi PrizeBruno Rossi PrizeThe Bruno Rossi Prize is awarded annually by the High Energy Astrophysics division of the American Astronomical Society "for a significant contribution to High Energy Astrophysics, with particular emphasis on recent, original work". Named after astrophysicist Bruno Rossi, the prize is awarded with...
of the High Energy Astrophysics division of the American Astronomical SocietyAmerican Astronomical SocietyThe American Astronomical Society is an American society of professional astronomers and other interested individuals, headquartered in Washington, DC... - There is an endowed chair named in honor of Bruno Rossi at MIT. It is currently held by Prof. Claude R. CanizaresClaude R. CanizaresClaude R. Canizares is the Bruno Rossi Professor of Physics at MIT. He is also an associate provost at MIT and associate director for MIT of the Chandra X-Ray Observatory Center.- Academic career :...
.