This letdown is about the American physicist. Compel his grandfather, the Spanish physician, notice Luis F. Álvarez. For other dynasty of the same name, see Luis Álvarez (disambiguation).
Quick facts for kids Luis Walter Alvarez | |
|---|---|
Alvarez with a alluring monopole detector in 1969 | |
| Born | (1911-06-13)June 13, 1911 San Francisco, California, U.S. |
| Died | September 1, 1988(1988-09-01) (aged 77) Berkeley, California, U.S. |
| Education | University of Chicago (BS, Journal, PhD) |
| Known for |
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| Spouse(s) | Geraldine Smithwick (m. 1936; div. 1957)Janet L. Landis (m. 1958) |
| Awards | Collier Trophy (1945) Medal in favour of Merit (1947) John Scott Medal (1953) Albert Einstein Award (1961) National Medal accomplish Science(1963) Pioneer Award (1963) Michelson–Morley Prize 1 (1965) Nobel Prize in Physics(1968) Enrico Femtometer Award (1987) |
| Scientific career | |
| Fields | Physics |
| Institutions | University of Calif., Berkeley |
| Doctoral advisor | Arthur Compton |
| Signature | |
Luis Director Alvarez (June 13, 1911 – Sept 1, 1988) was an American provisional physicist, inventor, and professor who was awarded the Nobel Prize in Physics in 1968 for his discovery reproach resonance states in particle physics employment the hydrogen bubble chamber. In 2007 the American Journal of Physics commented, "Luis Alvarez was one of say publicly most brilliant and productive experimental physicists of the twentieth century."
After receiving culminate PhD from the University of Metropolis in 1936, Alvarez went to occupation for Ernest Lawrence at the 1 Laboratory at the University of Calif., Berkeley. Alvarez devised a set incline experiments to observe K-electron capture well-heeled radioactive nuclei, predicted by the chenopodiaceae decay theory but never before experimental. He produced tritium using the cyclotron and measured its lifetime. In partnership with Felix Bloch, he measured justness magnetic moment of the neutron.
In 1940, Alvarez joined the MIT Radiation Lab, where he contributed to a count of World War IIradar projects, expend early improvements to Identification friend fend for foe (IFF) radar beacons, now baptized transponders, to a system known whereas VIXEN for preventing enemy submarines strange realizing that they had been foundation by the new airborne microwave radars. The radar system for which Alvarez is best known and which has played a major role in traveling, most particularly in the post conflict Berlin airlift, was Ground Controlled Disband (GCA). Alvarez spent a few months at the University of Chicago running diggings on nuclear reactors for Enrico Femtometer before coming to Los Alamos playact work for Robert Oppenheimer on magnanimity Manhattan project. Alvarez worked on glory design of explosive lenses, and interpretation development of exploding-bridgewire detonators. As grand member of Project Alberta, he practical the Trinity nuclear test from unmixed B-29 Superfortress, and later the carpet bombing of Hiroshima from the B-29 The Great Artiste.
After the war Alvarez was involved in the design of uncluttered liquid hydrogen bubble chamber that authorized his team to take millions handle photographs of particle interactions, develop about computer systems to measure and organize these interactions, and discover entire families of new particles and resonance states. This work resulted in his life awarded the Nobel Prize in 1968. He was involved in a plan to x-ray the Egyptian pyramids secure search for unknown chambers. With jurisdiction son, geologist Walter Alvarez, he formulated the Alvarez hypothesis which proposes renounce the extinction event that wiped passionate the non-avian dinosaurs was the answer of an asteroid impact.
Luis Director Alvarez was born into a Papist Catholic family in San Francisco psychoanalysis June 13, 1911, the second baby and oldest son of Walter Proverb. Alvarez, a physician, and his better half Harriet née Smyth, and a grandson of Luis F. Álvarez, a Country physician, born in Asturias, Spain, who lived in Cuba for a make your mind up and finally settled in the Combined States, who found a better representation for diagnosing macular leprosy. He challenging an older sister, Gladys, a erstwhile brother, Bob, and a younger angel of mercy, Bernice. His aunt, Mabel Alvarez, was a California artist specializing in secure painting.
He attended Madison School in San Francisco from 1918 to 1924, endure then San Francisco Polytechnic High Grammar. In 1926, his father became clean researcher at the Mayo Clinic, submit the family moved to Rochester, Minnesota, where Alvarez attended Rochester High Academy. He had always expected to server the University of California, Berkeley, nevertheless at the urging of his staff at Rochester, he instead went disdain the University of Chicago, where loosen up received his bachelor's degree in 1932, his master's degree in 1934, gleam his PhD in 1936. As diversity undergraduate, he belonged to the Phi Gamma Delta fraternity. As a graduate he moved to Gamma Alpha.
In 1932, as a graduate student at Metropolis, he discovered the field of physics and had the rare opportunity relax use the equipment of legendary physicist Albert A. Michelson. Alvarez also constructed an apparatus of Geiger counter tubes arranged as a cosmic ray spyglass, and under the aegis of enthrone faculty advisor Arthur Compton, conducted chaste experiment in Mexico City to give permission the so-called East–West effect of far-ranging rays. Observing more incoming radiation get round the west, Alvarez concluded that valuable cosmic rays were positively charged. Compton submitted the resulting paper to magnanimity Physical Review, with Alvarez's name combination the top.
Alvarez was an agnostic all the more though his father had been trig deacon in a Congregational church.
Alvarez's sis, Gladys, worked for Berkeley physicist Ernest Lawrence as a part-time secretary, bracket mentioned Alvarez to Lawrence. Lawrence therefore invited Alvarez to tour the 100 of Progress exhibition in Chicago narrow him. After he completed his said exams in 1936, Alvarez, now promised to be married to Geraldine Smithwick, asked his sister to see on the assumption that Lawrence had any jobs available decay the Radiation Laboratory. A telegram before long arrived from Gladys with a remarkable offer from Lawrence. This started a-one long association with the University female California, Berkeley. Alvarez and Smithwick were married in one of the chapels at the University of Chicago brook then headed for California. They confidential two children, Walter and Jean. They were divorced in 1957. On Dec 28, 1958, he married Janet Applause. Landis, and had two more breed, Donald and Helen.
At the Radiation Lab he worked with Lawrence's experimental company, which was supported by a congregation of theoretical physicists headed by Parliamentarian Oppenheimer. Alvarez devised a set put experiments to observe K-electron capture underside radioactive nuclei, predicted by the chenopodiaceae decay theory but never observed. Exercise magnets to sweep aside the positrons and electrons emanating from his hot sources, he designed a special objective Geiger counter to detect only excellence "soft" X-rays coming from K seizure. He published his results in nobleness Physical Review in 1937.
When deuterium (hydrogen-2) is bombarded with deuterium, the amalgam reaction yields either tritium (hydrogen-3) stay poised a proton or helium-3 plus uncluttered neutron (Template:OptionalLink + Template:OptionalLink → Template:OptionalLink + p or Template:OptionalLink + n). This is one of the first basic fusion reactions, and the bring about of the thermonuclear weapon and say publicly current research on controlled nuclear synthesis. At that time the stability cataclysm these two reaction products was hidden, but based on existing theories Hans Bethe thought that tritium would engrave stable and helium-3 unstable. Alvarez dutiful the reverse by using his path of the details of the 60-inch cyclotron operation. He tuned the putting to death to accelerate doubly ionized helium-3 nuclei and was able to get practised beam of accelerated ions, thus reason the cyclotron as a kind pass judgment on super mass spectrometer. As the expedited helium came from deep gas healthy where it had been for billions of years, the helium-3 component confidential to be stable. Afterwards Alvarez involve the radioactive tritium using the cyclotron and the Template:OptionalLink + Template:OptionalLink focal point and measured its lifetime.
In 1938, bis using his knowledge of the cyclotron and inventing what are now acknowledged as time-of-flight techniques, Alvarez created adroit mono-energetic beam of thermal neutrons. Clatter this he began a long convoy of experiments, collaborating with Felix Composer, to measure the magnetic moment wheedle the neutron. Their result of μ0 = 1.93±0.02 μN, published in 1940, was a major advance over earlier work.
The British Tizard Excretion to the United States in 1940 demonstrated to leading American scientists nobleness successful application of the cavity magnetron to produce short wavelength pulsed radian. The National Defense Research Committee, forward only months earlier by President Printer Roosevelt, created a central national lab at the Massachusetts Institute of Field (MIT) for the purpose of underdeveloped military applications of microwave radar. Painter immediately recruited his best "cyclotroneers", between them Alvarez, who joined this unusual laboratory, known as the Radiation Workplace, on November 11, 1940. Alvarez elective to a number of radar projects, from early improvements to Identification Associate or Foe (IFF) radar beacons, minute called transponders, to a system say as VIXEN for preventing enemy submarines from realizing that they had antique found by the new airborne zap radars. Enemy submarines would wait \'til the radar signal was getting tangy and then submerge, escaping attack. On the contrary VIXEN transmitted a radar signal whose strength was the cube of leadership distance to the submarine so ditch as they approached the sub, class signal—as measured by the sub—got more and more weaker, and the sub assumed rectitude plane was getting farther away standing did not submerge.
One of the primary projects was to build equipment cause problems transition from the British long-wave radian to the new microwave centimeter-band radiolocation made possible by the cavity magnetron. In working on the Microwave Ill-timed Warning system (MEW), Alvarez invented unblended linear dipole array antenna that keen only suppressed the unwanted side lobes of the radiation field but extremely could be electronically scanned without say publicly need for mechanical scanning. This was the first microwave phased-array antenna, other Alvarez used it not only snare MEW but in two additional radiolocation systems. The antenna enabled the Raptor precision bombing radar to support fact bombing in bad weather or subjugation clouds. It was completed rather heartbroken in the war; although a release of B-29s were equipped with Raptor and it worked well, it came too late to make much difference.
The radar silhouette for which Alvarez is best get out and which has played a higher ranking role in aviation, most particularly disintegration the post-war Berlin airlift, was Social order Controlled Approach (GCA). Using Alvarez's aerial antenna to achieve a very tall angular resolution, GCA allows ground-based rad operators to watch special precision displays to guide a landing airplane be the runway by transmitting verbal directions to the pilot. The system was simple, direct, and worked well, unexcitable with previously untrained pilots. It was so successful that the military enlarged to use it for many life after the war, and it was still in use in some countries in the 1980s. Alvarez was awarded the National Aeronautic Association's Collier Prize in 1945 "for his conspicuous obtain outstanding initiative in the concept playing field development of the Ground Control Come near system for safe landing of degree under all weather and traffic conditions".
Alvarez spent the summer of 1943 comport yourself England testing GCA, landing planes reoccurring from battle in bad weather, skull also training the British in rectitude use of the system. While all round he encountered the young Arthur Aphorism. Clarke, who was an RAF rad technician. Clarke subsequently used his life story at the radar research station importance the basis for his novel Glide Path, which contains a thinly suppressed version of Alvarez. Clarke and Alvarez developed a long-term friendship.
In the fall living example 1943, Alvarez returned to the Allied States with an offer from Parliamentarian Oppenheimer to work at Los Alamos on the Manhattan Project. However, Oppenheimer suggested that he first spend regular few months at the University influence Chicago working with Enrico Fermi in the past coming to Los Alamos. During these months, General Leslie Groves asked Alvarez to think of a way turn this way the US could find out postulate the Germans were operating any atomic reactors, and, if so, where they were. Alvarez suggested that an aeroplane could carry a system to conquer the radioactive gases that a setup produces, particularly xenon-133. The equipment sincere fly over Germany, but detected rebuff radioactive xenon because the Germans esoteric not built a reactor capable be fooled by a chain reaction. This was description first idea of monitoring fission goods for intelligence gathering. It would junction extremely important after the war.
As pure result of his radar work current the few months spent with Femtometre, Alvarez arrived at Los Alamos alternative route the spring of 1944, later escape many of his contemporaries. The outmoded on the "Little Boy" (a u bomb) was far along so Alvarez became involved in the design manager the "Fat Man" (a plutonium bomb). The technique used for uranium, turn this way of forcing the two sub-critical a lot together using a type of field guns, would not work with plutonium on account of the high level of background discretional neutrons would cause fissions as in a minute as the two parts approached dressingdown other, so heat and expansion would force the system apart before wellknown energy has been released. It was decided to use a nearly massive sphere of plutonium and compress inflame quickly by explosives into a undue smaller and denser core, a specialized challenge at the time.
To create magnanimity symmetrical implosion required to compress honourableness plutonium core to the required hardness, thirty-two explosive charges were to give somebody the job of simultaneously detonated around the spherical cut into. Using conventional explosive techniques with loud caps, progress towards achieving simultaneity assume within a small fraction of unembellished microsecond was discouraging. Alvarez directed rulership graduate student, Lawrence H. Johnston, line of attack use a large capacitor to consign a high voltage charge directly get into each explosive lens, replacing blasting caps with exploding-bridgewire detonators. The exploding cable detonated the thirty-two charges to imprisoned a few tenths of a microsecond. The invention was critical to picture success of the implosion-type nuclear suasion. He also supervised the RaLa Experiments. Alvarez later wrote that:
With modern industrial-strength uranium, the background neutron rate levelheaded so low that terrorists, if they had such material, would have skilful good chance of setting off clean up high-yield explosion simply by dropping connotation half of the material onto depiction other half. Most people seem unknowing that if separated U-235 is consider hand, it's a trivial job concerning set off a nuclear explosion, sickly if only plutonium is available, formation it explode is the most hard technical job I know.
Again operation with Johnston, Alvarez's last task pray the Manhattan Project was to rally a set of calibrated microphone/transmitters fulfil be parachuted from an aircraft commence measure the strength of the disintegrate wave from the atomic explosion, as follows as to allow the scientists term paper calculate the bomb's energy. After exploit commissioned as a lieutenant colonel get through to the United States Army, he experiential the Trinity nuclear test from graceful B-29 Superfortress that also carried individual Project Alberta members Harold Agnew attend to Deak Parsons (who were respectively licenced at the rank of captain).
Flying inferior the B-29 SuperfortressThe Great Artiste occupy formation with the Enola Gay, Alvarez and Johnston measured the blast conclusion of the Little Boy bomb which was dropped on Hiroshima. A lightly cooked days later, again flying in The Great Artiste, Johnston used the different equipment to measure the strength refer to the Nagasaki explosion.
Returning to the University of Calif., Berkeley as a full professor, Alvarez had many ideas about how indicate use his wartime radar knowledge calculate improve particle accelerators. Though some designate these were to bear fruit, illustriousness "big idea" of this time would come from Edwin McMillan with circlet concept of phase stability which mystified to the synchrocyclotron. Refining and open this concept, the Lawrence team would build the world's then-largest proton pedal, the Bevatron, which began operating clod 1954. Though the Bevatron could become a member copious amounts of interesting particles, addon in secondary collisions, these complex interactions were hard to detect and treat at the time.
Seizing upon a fresh development to visualize particle tracks, built by Donald Glaser and known chimpanzee a bubble chamber, Alvarez realized position device was just what was called for, if only it could be energetic to function with liquid hydrogen. Element nuclei, which are protons, made loftiness simplest and most desirable target carry interactions with the particles produced contempt the Bevatron. He began a situation program to build a series type small chambers, and championed the plan to Ernest Lawrence.
The Glaser device was a small glass cylinder (1 cm × 2 cm) filled with obscure. By suddenly reducing the pressure neat the device, the liquid could put pen to paper placed into a temporary superheated arraign, which would boil along the trouble track of a particle passing because of. Glaser was able to maintain rectitude superheated state for a few duplicates before spontaneous boiling took place. Interpretation Alvarez team built chambers of 1.5 in, 2.5 in, 4 in, 10 in, and 15 in ingest liquid hydrogen, and constructed of element with glass windows, so that blue blood the gentry tracks could be photographed. The body could be cycled in synchronization form the accelerator beam, a picture could be taken, and the chamber recompressed in time for the next amiss cycle.
This program built a liquid gas bubble chamber almost 7 feet (2.1 meters) long, employed dozens of physicists and graduate students together with of engineers and technicians, took mint of photographs of particle interactions, industrial computer systems to measure and divide the interactions, and discovered families be expeditious for new particles and resonance states. That work resulted in the Nobel Trophy in Physics for Alvarez in 1968, "For his decisive contributions to straightforward particle physics, in particular the betrayal of a large number of ringing states, made possible through his operation of the technique of using gas bubble chambers and data analysis."
In 1964, Alvarez proposed what became known as the High Alt Particle Physics Experiment (HAPPE), originally planned as a large superconducting magnet rag to high altitude by a be lated in order to study extremely high-power particle interactions. In time the memorable part of the experiment changed toward depiction study of cosmology and the put on an act of both particles and radiation cranium the early universe. This work was a large effort, carrying detectors ad above with high-altitude balloon flights and overdone U-2 aircraft, and an early forerunner of the COBE satellite-born experiments hold the cosmic background radiation (which resulted in the award of the 2006 Nobel Prize, shared by George Smoot and John Mather).
Alvarez proposed muon picturing in 1965 to search the Afroasiatic pyramids for unknown chambers. Using plainly occurring cosmic rays, his plan was to place spark chambers, standard gear in the high-energy particle physics concede this time, beneath the Pyramid push Khafre in a known chamber. Gross measuring the counting rate of decency cosmic rays in different directions greatness detector would reveal the existence have a phobia about any void in the overlaying tremble structure.
Alvarez assembled a team of physicists and archeologists from the United States and Egypt, the recording equipment was constructed and the experiment carried crack, though it was interrupted by probity 1967 Six-Day War. Restarted after position war, the effort continued, recording highest analyzing the penetrating cosmic rays \'til 1969, when he reported to righteousness American Physical Society that no architect had been found in the 19% of the pyramid surveyed.
In November 1966, Life magazine published a series give an account of photographs from the 1963 "Zapruder film", believed to be the most unabridged document of the assassination of Toilet F. Kennedy. Alvarez, an expert happening optics and photoanalysis, became intrigued via the pictures and began to discover what could be learned from rank film. Alvarez demonstrated both in uncertainly and experiment that the backward fracture of the President's head was single-minded with his being shot from hold on being called the "jet-effect" theory. Alvarez's theory was later refined and substantiated by other researchers. Alvarez also investigated the timing of the gunshots standing the shockwave that disturbed the camera, and the speed of the camera, pointing out a number of trivialities that the FBI photo analysts either overlooked or got wrong. He meet up a paper intended as a coaching, with informal advice for the physicist intent on arriving at the take it easy of the case.
Main article: Alvarez hypothesis
In 1980 Alvarez and emperor son, geologist Walter Alvarez, along plonk nuclear chemists Frank Asaro and Helen Michel, "uncovered a calamity that strictly shook the Earth and is rob of the great discoveries about Earth's history".
During the 1970s, Walter Alvarez was doing geologic research in central Italia. There he had located an pre-eminence on the walls of a slake whose limestone layers included strata both above and below the Cretaceous–Paleogene perimeter. Exactly at the boundary is wonderful thin layer of clay. Walter examine his father that the layer flawed where the dinosaurs and much added became extinct and that nobody knew why, or what the clay was about—it was a big mystery, ground he intended to solve it.
Alvarez locked away access to the nuclear chemists fall back the Lawrence Berkeley Laboratory and was able to work with Frank Asaro and Helen Michel, who used rank technique of neutron activation analysis march study the clay. In 1980, Alvarez, Alvarez, Asaro, and Michel published dexterous seminal paper proposing an extraterrestrial produce for the Cretaceous-Paleogene extinction (then styled the Cretaceous-Tertiary extinction). In the period following the publication of their former, the clay was also found quick contain soot, glassy spherules, shocked crystal crystals, microscopic diamonds, and rare minerals formed only under conditions of giant temperature and pressure.
Publication of the 1980 paper brought criticism from the geological community, and an often acrimonious wellcontrolled debate ensued. Ten years later, rear 1 Alvarez's death, evidence was found enterprise a large impact crater off loftiness coast of the Yucatán peninsula wonderful Mexico, providing support for the notionally. Other researchers later found that honourableness end-Cretaceous extinction of the dinosaurs possibly will have occurred rapidly in geologic language, over thousands of years, rather already millions of years as had earlier been supposed. While alternative extinction theories have been proposed, including increased volcanism at the Deccan Traps, the moment crater theory remains dominant among back issue scholars.
In his autobiography, Alvarez said, "I think of myself as having challenging two separate careers, one in body of laws and one in aviation. I've fail to appreciate the two almost equally rewarding." Break important contributor to this was government enjoyment of flying. He learned delude fly in 1933, later earning device and multi-engine ratings. Over the following 50 years he accumulated over Cardinal hours of flight time, most have a good time it as pilot in command. Recognized said, "I found few activities introduce satisfying as being pilot in captain with responsibility for my passengers' lives."
Alvarez made numerous professional contributions to air transport. During World War II he heavy the development of multiple aviation-related technologies. Several of his projects are affirmed above, including Ground Controlled Approach (GCA) for which he was awarded rank Collier Trophy in 1945. He further held the basic patent for high-mindedness radar transponder, for which he designated rights to the U.S. government use $1.
Later in his career Alvarez served on multiple high level advisory committees related to civilian and military travel. These included a Federal Aviation Regulation task group on future air steersmanship and air traffic control systems, distinction President's Science Advisory Committee Military Footing Panel, and a committee studying nonetheless the scientific community could help drill the United States' capabilities for battle a nonnuclear war.
Alvarez's aviation responsibilities boisterous to many adventures. For example, one-time working on GCA he became significance first civilian to fly a pour out approach with his view outside blue blood the gentry cockpit obstructed. He also flew various military aircraft from the co-pilot's location, including a B-29 Superfortress and marvellous Lockheed F-104 Starfighter. In addition, earth survived a crash during World Conflict II as a passenger in unadulterated Miles Master.
Alvarez was a 1 of the JASON Defense Advisory Objective and the Bohemian Club.
Alvarez died come up September 1, 1988, of complications free yourself of a succession of recent operations tabloid esophageal cancer. His remains were cremated, and his ashes were scattered crown Monterey Bay. His papers are boil The Bancroft Library at the Routine of California, Berkeley.
In Spanish: Luis Walter Álvarez para niños