Nathan Isgur
Encyclopedia
Theoretical physics
Theoretical physics is a branch of physics which employs mathematical models and abstractions of physics to rationalize, explain and predict natural phenomena...
from the U.S.
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
and Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
.
Education
Isgur was born in South Houston, TexasSouth Houston, Texas
South Houston is a city in Harris County, Texas within the Houston–Sugar Land–Baytown metropolitan area. The population was 15,833 at the 2000 census. It is bordered by the city of Houston and the city of Pasadena.-History:...
and finished high school at South Houston High School
South Houston High School
South Houston High School, nicknamed SOHO, is a high school located in South Houston, Texas, United States.South Houston, which serves grades 9 through 12, is a part of the Pasadena Independent School District. As of 2008 the principal is Dr...
. He was a scholarship student at Caltech
California Institute of Technology
The California Institute of Technology is a private research university located in Pasadena, California, United States. Caltech has six academic divisions with strong emphases on science and engineering...
. where his initial interest was in biology, but he moved toward physics and graduated with a B.Sc
Bachelor of Science
A Bachelor of Science is an undergraduate academic degree awarded for completed courses that generally last three to five years .-Australia:In Australia, the BSc is a 3 year degree, offered from 1st year on...
degree in 1968. Isgur began work on his doctorate at the University of California, Berkeley
University of California, Berkeley
The University of California, Berkeley , is a teaching and research university established in 1868 and located in Berkeley, California, USA...
, but received his draft notice during his first year there. Denied a draft deferment to continue his education at Berkeley he went to Toronto
Toronto
Toronto is the provincial capital of Ontario and the largest city in Canada. It is located in Southern Ontario on the northwestern shore of Lake Ontario. A relatively modern city, Toronto's history dates back to the late-18th century, when its land was first purchased by the British monarchy from...
in order to pursue his graduate studies and to avoid serving in a war he disagreed with on moral and political grounds. Isgur received a letter of introduction from Nobel Laureate Owen Chamberlain
Owen Chamberlain
Owen Chamberlain was an American physicist, and Nobel laureate in physics for his discovery, with collaborator Emilio Segrè, of antiprotons, a sub-atomic antiparticle.-Biography:...
at Berkeley, to R.E. Pugh, at the University of Toronto
University of Toronto
The University of Toronto is a public research university in Toronto, Ontario, Canada, situated on the grounds that surround Queen's Park. It was founded by royal charter in 1827 as King's College, the first institution of higher learning in Upper Canada...
, who took him on as a graduate student. Isgur received a Ph.D.
Ph.D.
A Ph.D. is a Doctor of Philosophy, an academic degree.Ph.D. may also refer to:* Ph.D. , a 1980s British group*Piled Higher and Deeper, a web comic strip*PhD: Phantasy Degree, a Korean comic series* PhD Docbook renderer, an XML renderer...
degree in particle theory
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 Toronto in 1974.
War draft
Isgur eventually took out Canadian citizenship owing to his inability to travel, having been unable to renew his US passport due to his draft status, and because of his position as a war resisterWar resister
A war resister is a person who resists war. The term can mean several things: resisting participation in all war, or a specific war, either before or after enlisting in, being inducted into, or being conscripted into a military force....
. This situation continued to inhibit his ability to travel to the United States until President Jimmy Carter
Jimmy Carter
James Earl "Jimmy" Carter, Jr. is an American politician who served as the 39th President of the United States and was the recipient of the 2002 Nobel Peace Prize, the only U.S. President to have received the Prize after leaving office...
issued a blanket amnesty for all draft resisters.
Work
After completion of his Doctorate, Isgur was granted a Natural Sciences and Engineering Research CouncilNatural Sciences and Engineering Research Council
The Natural Sciences and Engineering Research Council of Canada is a Canadian government agency that provides grants for research in the natural sciences and in engineering. Its mandate is to promote and assist research....
Fellowship, which allowed him to stay at Toronto as a post-doctoral candidate. He was hired as an assistant professor in the Department of Physics in 1976 in recognition of his outstanding merit by department head Robin Armstrong, even though he had not been able to travel to gain experience outside the Department owing to passport difficulties. In 1975 Isgur published on the mixing angle of pseudo-scalar meson
Meson
In particle physics, mesons are subatomic particles composed of one quark and one antiquark, bound together by the strong interaction. Because mesons are composed of sub-particles, they have a physical size, with a radius roughly one femtometer: 10−15 m, which is about the size of a proton...
s due to annihilation into gluon
Gluon
Gluons are elementary particles which act as the exchange particles for the color force between quarks, analogous to the exchange of photons in the electromagnetic force between two charged particles....
s. He embarked on a long collaboration with Gabriel Karl from the University of Guelph
University of Guelph
The University of Guelph, also known as U of G, is a comprehensive public research university in Guelph, Ontario, Canada. It was established in 1964 after the amalgamation of Ontario Agricultural College, the Macdonald Institute, and the Ontario Veterinary College...
, involving the study of excited baryons in quark
Quark
A quark is an elementary particle and a fundamental constituent of matter. Quarks combine to form composite particles called hadrons, the most stable of which are protons and neutrons, the components of atomic nuclei. Due to a phenomenon known as color confinement, quarks are never directly...
models. The principal physical idea of the model was taken from quantum chromodynamics
Quantum chromodynamics
In theoretical physics, quantum chromodynamics is a theory of the strong interaction , a fundamental force describing the interactions of the quarks and gluons making up hadrons . It is the study of the SU Yang–Mills theory of color-charged fermions...
: the forces between quarks are flavour
Flavour (particle physics)
In particle physics, flavour or flavor is a quantum number of elementary particles. In quantum chromodynamics, flavour is a global symmetry...
-independent. This idea gave rise to their "QCD-improved" quark model.
Isgur had a large group of graduate students, usually 5-6 at a given time. During his 14 years at the University of Toronto, he mentored 13 Ph.D.s: Simon Capstick, Kevin Dooley, Paul Geiger, Stephen Godfrey, Gregory Grondin, Richard Kokoski, Roman Koniuk, David Kotchan, Kim Maltman, Colin Morningstar, Catherine Reader, Eric Swanson, and John Weinstein.
Two conferences he organized included the Baryon Conference (1980) in Toronto and the Advanced Study Institute on Quark Interactions at Whitehorse, Yukon (1984) useful in the development of light and heavy quark spectroscopy.
Isgur was one of the leaders of the CHEER project, this envisaged an electron ring to be built at Fermilab
Fermilab
Fermi National Accelerator Laboratory , located just outside Batavia, Illinois, near Chicago, is a US Department of Energy national laboratory specializing in high-energy particle physics...
by a Canadian group to study electron-proton collisions. CHEER was not funded, in favor of the Tevatron
Tevatron
The Tevatron is a circular particle accelerator in the United States, at the Fermi National Accelerator Laboratory , just east of Batavia, Illinois, and is the second highest energy particle collider in the world after the Large Hadron Collider...
proton–antiproton collider, but led to a strong Canadian involvement in the ZEUS
Zeus
In the ancient Greek religion, Zeus was the "Father of Gods and men" who ruled the Olympians of Mount Olympus as a father ruled the family. He was the god of sky and thunder in Greek mythology. His Roman counterpart is Jupiter and his Etruscan counterpart is Tinia.Zeus was the child of Cronus...
experiment at the HERA
Hera
Hera was the wife and one of three sisters of Zeus in the Olympian pantheon of Greek mythology and religion. Her chief function was as the goddess of women and marriage. Her counterpart in the religion of ancient Rome was Juno. The cow and the peacock were sacred to her...
electron-proton collider in Hamburg
Hamburg
-History:The first historic name for the city was, according to Claudius Ptolemy's reports, Treva.But the city takes its modern name, Hamburg, from the first permanent building on the site, a castle whose construction was ordered by the Emperor Charlemagne in AD 808...
, Germany
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
.
He returned to the USA to the newly built accelerator at Newport News (CEBAF), which eventually became Jefferson Lab, to build an entirely new Theory Group and influence the experimental research of the Laboratory. Isgur become the head of the Theory Group at Jefferson Lab in 1990 and eventually became the chief scientist in 1996. He joined the faculty at William and Mary College at Williamsburg.
Isgur and Mark Wise
Mark B. Wise
Mark Brian Wise is a Canadian-American theoretical physicist. He has conducted research in elementary particle physics and cosmology...
studied the semileptonic decays of mesons with a charm and bottom quark and they discovered what is now known as the heavy quark symmetry of QCD. This symmetry, which becomes exact for infinitely heavy quarks, leads to important simplifications of form-factors in such decays.
He was also involved later on in several Natural Sciences and Engineering Research Council
Natural Sciences and Engineering Research Council
The Natural Sciences and Engineering Research Council of Canada is a Canadian government agency that provides grants for research in the natural sciences and in engineering. Its mandate is to promote and assist research....
grant selection committees, becoming the Chair of the Subatomic Physics GSC in the early 1990s. Isgur was influential in changing the manner in which nuclear and particle physics was funded in Canada, helping to bring in an "envelope" system of funding for subatomic physics. He took a strong interest in TRIUMF
TRIUMF
TRIUMF is Canada’s national laboratory for particle and nuclear physics. Its headquarters are located on the south campus of the University of British Columbia in Vancouver, British Columbia. TRIUMF houses the world's largest cyclotron, source of 500 MeV protons, which was named an IEEE Milestone...
, Canada's premiere particle and nuclear physics facility.
He was diagnosed with multiple myeloma
Multiple myeloma
Multiple myeloma , also known as plasma cell myeloma or Kahler's disease , is a cancer of plasma cells, a type of white blood cell normally responsible for the production of antibodies...
in 1996, and died five years later.
Awards
The work with Wise led to them receiving the Sakurai PrizeSakurai Prize
The J. J. Sakurai Prize for Theoretical Particle Physics, is presented by the American Physical Society at its annual "April Meeting", and honors outstanding achievement in particle physics theory...
of the APS in 2001, jointly with M. Voloshin. Isgur was also a recipient of the Herzberg Prize (CAP), the Steacie Fellowship and Prize (NSERC), and the Rutherford Memorial Medal
Rutherford Memorial Medal
The Rutherford Memorial Medal is an award for research in the fields of physics and chemistry by the Royal Society of Canada. It was dedicated to the memorial of Ernest Rutherford.-Physics:* 2010 : Kari Dalnoki-Veress* 2009 : Barth Nettlefield...
in Physics (RSC). He was a Fellow of the Royal Society of Canada
Royal Society of Canada
The Royal Society of Canada , may also operate under the more descriptive name RSC: The Academies of Arts, Humanities and Sciences of Canada , is the oldest association of scientists and scholars in Canada...
and of the American Physical Society
American Physical Society
The American Physical Society is the world's second largest organization of physicists, behind the Deutsche Physikalische Gesellschaft. The Society publishes more than a dozen scientific journals, including the world renowned Physical Review and Physical Review Letters, and organizes more than 20...
.