Harold R. Kaufman (born November 24, 1926 - January 4, 2018) was an American

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 caus ...

, noted for his development of electrostatic

ion thruster An ion thruster, ion drive, or ion engine is a form of electric propulsion used for spacecraft propulsion. It creates thrust by accelerating ions using electricity. An ion thruster ionizes a neutral gas by extracting some electrons out of a ...

s for NASA during the 1950s and 1960s. Kaufman developed a compact

ion source An ion source is a device that creates atomic and molecular ions. Ion sources are used to form ions for mass spectrometers, optical emission spectrometers, particle accelerators, ion implanters and ion engines. Electron ionization Electron ...

based on electron bombardment, the "Kaufman Ion Source," a variant of the

duoplasmatron The Duoplasmatron is an ion source in which a cathode filament emits electrons into a vacuum chamber. A gas such as argon is introduced in very small quantities into the chamber, where it becomes charged or ionized through interactions with the ...

, for the purpose of

spacecraft propulsion Spacecraft propulsion is any method used to accelerate spacecraft and artificial satellites. In-space propulsion exclusively deals with propulsion systems used in the vacuum of space and should not be confused with space launch or atmospheric e ...

Biography

Born in

Audubon, Iowa Audubon is a city and the county seat in Audubon County, Iowa, United States. The population was 2,053 in the 2020 census, a decline from 2,382 in the 2000 census. History The city is named for John James Audubon the world-famous ornithologist, ...

, USA, in 1926, Kaufman grew up in

Evanston, Illinois Evanston ( ) is a city, suburb of Chicago. Located in Cook County, Illinois, United States, it is situated on the North Shore along Lake Michigan. Evanston is north of Downtown Chicago, bordered by Chicago to the south, Skokie to the west, Wil ...

, a suburb of

Chicago (''City in a Garden''); I Will , image_map = , map_caption = Interactive Map of Chicago , coordinates = , coordinates_footnotes = , subdivision_type = Country , subdivision_name ...

.Albert Nerkin Award Winners
/ref> He trained in electrical engineering during World War II through an electronic technician program in the US Navy. After the war ended, he took a B.S. degree in mechanical engineering from

Northwestern University Northwestern University is a private research university in Evanston, Illinois. Founded in 1851, Northwestern is the oldest chartered university in Illinois and is ranked among the most prestigious academic institutions in the world. Charte ...

. After college he joined the

National Advisory Committee for Aeronautics The National Advisory Committee for Aeronautics (NACA) was a United States federal agency founded on March 3, 1915, to undertake, promote, and institutionalize aeronautical research. On October 1, 1958, the agency was dissolved and its assets ...

(NACA), the predecessor of

NASA The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research. NASA was established in 1958, succeeding t ...

, working on turbo jet engines at the

Lewis Research Center NASA John H. Glenn Research Center at Lewis Field is a NASA center within the cities of Brook Park and Cleveland between Cleveland Hopkins International Airport and the Rocky River Reservation of Cleveland Metroparks, with a subsidiary facilit ...

(now NASA Glenn) in

Cleveland Cleveland ( ), officially the City of Cleveland, is a city in the U.S. state of Ohio and the county seat of Cuyahoga County. Located in the northeastern part of the state, it is situated along the southern shore of Lake Erie, across the U.S. ...

. He then moved to a group studying electric space propulsion. After concluding that a Von Ardenne source was insufficient, he developed the electron bombardment source in 1958/59., and was responsible for the development of two ion thrusters that were tested in space (

SERT-1 SERT-1 (Space Electric Rocket Test) was a NASA probe used to test electrostatic ion thruster design and was built by NASA's Lewis Research Center (now NASA Glenn). SERT-1 was the first spacecraft to utilize ion engine design. It was launched on ...

and SERT-II missions). The Kaufman ion source is now also used for other applications, such as

ion implanter Ion implantation is a low-temperature process by which ions of one element are accelerated into a solid target, thereby changing the physical, chemical, or electrical properties of the target. Ion implantation is used in semiconductor device fab ...

s used in

semiconductor A semiconductor is a material which has an electrical resistivity and conductivity, electrical conductivity value falling between that of a electrical conductor, conductor, such as copper, and an insulator (electricity), insulator, such as glas ...

processing. He was awarded an Exceptional Scientific Achievement Award by NASA in 1971. Kaufman was awarded a Ph.D. from

Colorado State University Colorado State University (Colorado State or CSU) is a public land-grant research university in Fort Collins, Colorado. It is the flagship university of the Colorado State University System. Colorado State University is classified among "R1: ...

in 1970, joining the university as staff in 1974. He left academia in 1984 to work at Kaufman & Robinson, Inc., in

Fort Collins, Colorado Fort Collins is a home rule municipality that is the county seat and the most populous municipality of Larimer County, Colorado Larimer County is a county located in the U.S. state of Colorado. As of the 2020 census, the population was 359 ...

, and invented the end-Hall ion source in 1989. In 1991, the AVS awarded him its Albert Nerkin Award. In September 2016, Kaufman was inducted into the NASA Hall of Fame for his advances in ion propulsion. He was a Professor Emeritus of the CSU department of

physics Physics is the natural science that studies matter, its 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 which r ...

References

External links

Harold R. Kaufman with his electron bombardment ion thruster
{{DEFAULTSORT:Kaufman, Harold R. 21st-century American physicists 1926 births 2018 deaths People from Audubon, Iowa People from Evanston, Illinois Northwestern University alumni Colorado State University alumni