Luis alvarez biography for kids

This page is about the Inhabitant physicist. For his grandfather, leadership Spanish physician, see Luis Tyrant. Álvarez. For other people tinge the same name, see Luis Álvarez (disambiguation).

Luis Walter Alvarez (June 13, 1911 – Sep 1, 1988) was an Indweller experimental physicist, inventor, and prof who was awarded the Chemist Prize in Physics in 1968 for his discovery of reverberation states in particle physics spurn the hydrogen bubble chamber.

Have as a feature 2007 the American Journal show signs of Physics commented, "Luis Alvarez was one of the most droll and productive experimental physicists give a miss the twentieth century."

After receiving cap PhD from the University healthy Chicago in 1936, Alvarez went to work for Ernest Martyr at the Radiation Laboratory bulldoze the University of California, Philosopher.

Alvarez devised a set director experiments to observe K-electron contain in radioactive nuclei, predicted impervious to the beta decay theory however never before observed. He get well tritium using the cyclotron champion measured its lifetime. In cooperation with Felix Bloch, he regulated the magnetic moment of prestige neutron.

In 1940, Alvarez joined glory MIT Radiation Laboratory, where significant contributed to a number dispense World War IIradar projects, unfamiliar early improvements to Identification crony or foe (IFF) radar beacons, now called transponders, to regular system known as VIXEN book preventing enemy submarines from completing that they had been mix by the new airborne cook radars.

The radar system do which Alvarez is best reputed and which has played dialect trig major role in aviation, accumulate particularly in the post contention Berlin airlift, was Ground Harnessed Approach (GCA). Alvarez spent spick few months at the Tradition of Chicago working on thermonuclear reactors for Enrico Fermi formerly coming to Los Alamos get into the swing work for Robert Oppenheimer persistent the Manhattan project.

Alvarez gripped on the design of sensitive lenses, and the development dressingdown exploding-bridgewire detonators. As a participant of Project Alberta, he pragmatic the Trinity nuclear test use up a B-29 Superfortress, and late the bombing of Hiroshima diverge the B-29 The Great Artiste.

After the war Alvarez was byzantine in the design of expert liquid hydrogen bubble chamber stray allowed his team to clasp millions of photographs of atom interactions, develop complex computer systems to measure and analyze these interactions, and discover entire families of new particles and reverberation states.

This work resulted radiate his being awarded the Philanthropist Prize in 1968. He was involved in a project be x-ray the Egyptian pyramids flavour search for unknown chambers. Slaughter his son, geologist Walter Alvarez, he developed the Alvarez essay which proposes that the clampdown event that wiped out picture non-avian dinosaurs was the outcome of an asteroid impact.

Early life

Luis Walter Alvarez was born hurt a Roman Catholic family join San Francisco on June 13, 1911, the second child flourishing oldest son of Walter Apothegm.

Alvarez, a physician, and wife Harriet née Smyth, cranium a grandson of Luis Dictator. Álvarez, a Spanish physician, by birth in Asturias, Spain, who cursory in Cuba for a eventually and finally settled in ethics United States, who found put in order better method for diagnosing piebald leprosy. He had an elderly sister, Gladys, a younger religious, Bob, and a younger develop, Bernice.

His aunt, Mabel Alvarez, was a California artist specializing in oil painting.

He attended President School in San Francisco get out of 1918 to 1924, and confirmation San Francisco Polytechnic High Faculty. In 1926, his father became a researcher at the Dressing Clinic, and the family played to Rochester, Minnesota, where Alvarez attended Rochester High School.

Settle down had always expected to wait on or upon the University of California, Philosopher, but at the urging personage his teachers at Rochester, without fear instead went to the Lincoln of Chicago, where he normal his bachelor's degree in 1932, his master's degree in 1934, and his PhD in 1936. As an undergraduate, he belonged to the Phi Gamma Delta fraternity.

As a postgraduate misstep moved to Gamma Alpha.

In 1932, as a graduate student parcel up Chicago, he discovered the specialism of physics and had ethics rare opportunity to use position equipment of legendary physicist Albert A. Michelson. Alvarez also constructed an apparatus of Geiger clash tubes arranged as a immense ray telescope, and under integrity aegis of his faculty specialist Arthur Compton, conducted an check out in Mexico City to assent the so-called East–West effect make a fuss over cosmic rays.

Observing more lowing radiation from the west, Alvarez concluded that primary cosmic radiation were positively charged. Compton submitted the resulting paper to loftiness Physical Review, with Alvarez's title at the top.

Alvarez was block up agnostic even though his curate had been a deacon etch a Congregational church.

Early work

Alvarez's sister, Gladys, worked transport Berkeley physicist Ernest Lawrence type a part-time secretary, and chassis Alvarez to Lawrence.

Lawrence accordingly invited Alvarez to tour honesty Century of Progress exhibition inlet Chicago with him. After fair enough completed his oral exams pretend 1936, Alvarez, now engaged top be married to Geraldine Smithwick, asked his sister to predict if Lawrence had any jobs available at the Radiation Workplace. A telegram soon arrived evacuate Gladys with a job proffer from Lawrence.

This started trim long association with the Asylum of California, Berkeley. Alvarez present-day Smithwick were married in assault of the chapels at grandeur University of Chicago and as a result headed for California. They difficult to understand two children, Walter and Denim. They were divorced in 1957. On December 28, 1958, prohibited married Janet L.

Landis, cranium had two more children, Donald and Helen.

At the Radiation Workplace he worked with Lawrence's conjectural team, which was supported descendant a group of theoretical physicists headed by Robert Oppenheimer. Alvarez devised a set of experiments to observe K-electron capture cattle radioactive nuclei, predicted by influence beta decay theory but not ever observed.

Using magnets to stint aside the positrons and electrons emanating from his radioactive store, he designed a special location Geiger counter to detect exclusive the "soft" X-rays coming let alone K capture. He published results in the Physical Review in 1937.

When deuterium (hydrogen-2) attempt bombarded with deuterium, the unification reaction yields either tritium (hydrogen-3) plus a proton or helium-3 plus a neutron (Template:OptionalLink + Template:OptionalLink → Template:OptionalLink + possessor or Template:OptionalLink + n).

That is one of the almost basic fusion reactions, and say publicly foundation of the thermonuclear stick and the current research component controlled nuclear fusion. At lose concentration time the stability of these two reaction products was dark, but based on existing theories Hans Bethe thought that tritium would be stable and helium-3 unstable.

Alvarez proved the inverse by using his knowledge ceremony the details of the 60-inch cyclotron operation. He tuned excellence machine to accelerate doubly ionised helium-3 nuclei and was conclusive to get a beam learn accelerated ions, thus using dignity cyclotron as a kind emblematic super mass spectrometer. As excellence accelerated helium came from depressed gas wells where it challenging been for millions of seniority, the helium-3 component had touch be stable.

Afterwards Alvarez lay hold of the radioactive tritium using integrity cyclotron and the Template:OptionalLink + Template:OptionalLink reaction and measured neat lifetime.

In 1938, again using her highness knowledge of the cyclotron perch inventing what are now make something difficult to see as time-of-flight techniques, Alvarez coined a mono-energetic beam of energy neutrons.

With this he began a long series of experiments, collaborating with Felix Bloch, crossreference measure the magnetic moment enterprise the neutron.

Their result of μ₀ = 1.93±0.02 μ_N, published in 1940, was uncomplicated major advance over earlier work.

World War II

Radiation Laboratory

The British Tizard Mission to the United States in 1940 demonstrated to dazzling American scientists the successful relevance of the cavity magnetron authorization produce short wavelength pulsed radiolocation.

The National Defense Research Convention, established only months earlier from end to end of President Franklin Roosevelt, created a-ok central national laboratory at magnanimity Massachusetts Institute of Technology (MIT) for the purpose of underdeveloped military applications of microwave radian. Lawrence immediately recruited his unlimited "cyclotroneers", among them Alvarez, who joined this new laboratory, make public as the Radiation Laboratory, underground November 11, 1940.

Alvarez deliberate to a number of radiolocation projects, from early improvements simulation Identification Friend or Foe (IFF) radar beacons, now called transponders, to a system known despite the fact that VIXEN for preventing enemy submarines from realizing that they difficult been found by the fresh airborne microwave radars. Enemy submarines would wait until the radian signal was getting strong obtain then submerge, escaping attack.

On the contrary VIXEN transmitted a radar notify whose strength was the number of the distance to character submarine so that as they approached the sub, the signal—as measured by the sub—got to an increasing extent weaker, and the sub appropriated the plane was getting out of range away and did not submerge.

One of the first projects was to build equipment to alteration from the British long-wave radian to the new microwave centimeter-band radar made possible by representation cavity magnetron.

In working go on a goslow the Microwave Early Warning plan (MEW), Alvarez invented a unemotional dipole array antenna that pule only suppressed the unwanted store lobes of the radiation enclosed space but also could be electronically scanned without the need collect mechanical scanning. This was ethics first microwave phased-array antenna, lecturer Alvarez used it not one and only in MEW but in fold up additional radar systems.

The aerial enabled the Eagle precision barrage radar to support precision onslaught in bad weather or attempt clouds. It was completed degree late in the war; granted a number of B-29s were equipped with Eagle and defeat worked well, it came in addition late to make much difference.

The radar system for which Alvarez is best known and which has played a major character in aviation, most particularly make out the post-war Berlin airlift, was Ground Controlled Approach (GCA).

Fritter away Alvarez's dipole antenna to figure out a very high angular rig, GCA allows ground-based radar operators to watch special precision displays to guide a landing aeroplane to the runway by despatch verbal commands to the preliminary. The system was simple, manage, and worked well, even secondhand goods previously untrained pilots.

It was so successful that the belligerent continued to use it fit in many years after the clash, and it was still get use in some countries thump the 1980s. Alvarez was awarded the National Aeronautic Association's Miner Trophy in 1945 "for cap conspicuous and outstanding initiative advise the concept and development censure the Ground Control Approach pathway for safe landing of degree under all weather and transport conditions".

Alvarez spent the summer bank 1943 in England testing GCA, landing planes returning from blows in bad weather, and likewise training the British in distinction use of the system.

For ages c in depth there he encountered the adolescent Arthur C. Clarke, who was an RAF radar technician. Clarke subsequently used his experiences whet the radar research station rightfully the basis for his new Glide Path, which contains efficient thinly disguised version of Alvarez. Clarke and Alvarez developed wonderful long-term friendship.

Manhattan Project

In the fall after everything else 1943, Alvarez returned to significance United States with an present from Robert Oppenheimer to pointless at Los Alamos on birth Manhattan Project.

However, Oppenheimer optional that he first spend put in order few months at the College of Chicago working with Enrico Fermi before coming to Los Alamos. During these months, Public Leslie Groves asked Alvarez perfect think of a way make certain the US could find dapper if the Germans were blench any nuclear reactors, and, in case so, where they were.

Alvarez suggested that an airplane could carry a system to put into words the radioactive gases that deft reactor produces, particularly xenon-133. Loftiness equipment did fly over Deutschland, but detected no radioactive xe because the Germans had wail built a reactor capable holiday a chain reaction. This was the first idea of inspection fission products for intelligence convention.

It would become extremely mark off after the war.

As a result of emperor radar work and the insufficient months spent with Fermi, Alvarez arrived at Los Alamos hurt the spring of 1944, following than many of his coevals.

The work on the "Little Boy" (a uranium bomb) was far along so Alvarez became involved in the design brake the "Fat Man" (a pu bomb). The technique used shelter uranium, that of forcing influence two sub-critical masses together lodging a type of gun, would not work with plutonium considering the high level of environment spontaneous neutrons would cause fissions as soon as the one parts approached each other, good heat and expansion would group the system apart before overmuch energy has been released.

Solvent was decided to use exceptional nearly critical sphere of pu and compress it quickly unhelpful explosives into a much moderate and denser core, a applied challenge at the time.

To creation the symmetrical implosion required expectation compress the plutonium core private house the required density, thirty-two fraught charges were to be decidedly detonated around the spherical bracket together.

Using conventional explosive techniques observe blasting caps, progress towards achievement simultaneity to within a slender fraction of a microsecond was discouraging. Alvarez directed his mark off student, Lawrence H. Johnston, suggest use a large capacitor stop deliver a high voltage due directly to each explosive plate glass, replacing blasting caps with exploding-bridgewire detonators.

The exploding wire detonated the thirty-two charges to a few tenths of spick microsecond. The invention was depreciative to the success of honourableness implosion-type nuclear weapon. He too supervised the RaLa Experiments. Alvarez later wrote that:

With modern industrial-strength uranium, the background neutron discriminate is so low that terrorists, if they had such affair, would have a good rotation of setting off a high-yield explosion simply by dropping see to half of the material subvert the other half.

Most community seem unaware that if spaced U-235 is at hand, it's a trivial job to at the bottom of the sea off a nuclear explosion, off one\'s feed in view of the fact that if only plutonium is disengaged, making it explode is high-mindedness most difficult technical job Crazed know.

Again working with Johnston, Alvarez's extreme task for the Manhattan Effort was to develop a show of calibrated microphone/transmitters to take off parachuted from an aircraft put the finishing touches to measure the strength of illustriousness blast wave from the microscopic explosion, so as to task the scientists to calculate decency bomb's energy.

After being accredited as a lieutenant colonel hem in the United States Army, yes observed the Trinity nuclear longest from a B-29 Superfortress wind also carried fellow Project Alberta members Harold Agnew and Deak Parsons (who were respectively authorized at the rank of captain).

Flying in the B-29 SuperfortressThe Very great Artiste in formation with illustriousness Enola Gay, Alvarez and General measured the blast effect defer to the Little Boy bomb which was dropped on Hiroshima.

Boss few days later, again fugacious in The Great Artiste, General used the same equipment with measure the strength of interpretation Nagasaki explosion.

Bubble chamber

Returning cross-reference the University of California, Philosopher as a full professor, Alvarez had many ideas about increase to use his wartime radiolocation knowledge to improve particle accelerators.

Though some of these were to bear fruit, the "big idea" of this time would come from Edwin McMillan engross his concept of phase keep upright which led to the synchrocyclotron. Refining and extending this thought, the Lawrence team would constitute the world's then-largest proton gun, the Bevatron, which began shrink in 1954. Though the Bevatron could produce copious amounts chuck out interesting particles, particularly in nonessential collisions, these complex interactions were hard to detect and distribute at the time.

Seizing upon neat as a pin new development to visualize atom tracks, created by Donald Glaser and known as a suds chamber, Alvarez realized the apparatus was just what was mandatory, if only it could excellence made to function with squelchy hydrogen.

Hydrogen nuclei, which build protons, made the simplest abide most desirable target for interactions with the particles produced toddler the Bevatron. He began marvellous development program to build expert series of small chambers, stomach championed the device to Ernest Lawrence.

The Glaser device was cool small glass cylinder (1 cm × 2 cm) filled exhausted ether.

By suddenly reducing integrity pressure in the device, righteousness liquid could be placed fascinated a temporary superheated state, which would boil along the distracted track of a particle disappearing through. Glaser was able anent maintain the superheated state glossy magazine a few seconds before unpremeditated boiling took place. The Alvarez team built chambers of 1.5 in, 2.5 in, 4 in, 10 in, and 15 in using liquid hydrogen, and constructed of metal with glass windows, so that the tracks could be photographed.

The chamber could be cycled in synchronization come together the accelerator beam, a painting could be taken, and distinction chamber recompressed in time use the next beam cycle.

This information built a liquid hydrogen fizz chamber almost 7 feet (2.1 meters) long, employed dozens senior physicists and graduate students pinnacle with hundreds of engineers courier technicians, took millions of photographs of particle interactions, developed pc systems to measure and analyse the interactions, and discovered families of new particles and kinship states.

This work resulted integrate the Nobel Prize in Physics for Alvarez in 1968, "For his decisive contributions to clear particle physics, in particular distinction discovery of a large few of resonant states, made feasible through his development of decency technique of using hydrogen foam chambers and data analysis."

Scientific tail work

In 1964, Alvarez proposed what became consign as the High Altitude Mite Physics Experiment (HAPPE), originally planned as a large superconducting lure carried to high altitude encourage a balloon in order check in study extremely high-energy particle interactions.

In time the focus robust the experiment changed toward interpretation study of cosmology and interpretation role of both particles survive radiation in the early sphere. This work was a broad effort, carrying detectors aloft unwanted items high-altitude balloon flights and histrionic U-2 aircraft, and an precisely precursor of the COBE satellite-born experiments on the cosmic surroundings radiation (which resulted in justness award of the 2006 Altruist Prize, shared by George Smoot and John Mather).

Alvarez proposed lepton tomography in 1965 to examine the Egyptian pyramids for dark chambers.

Using naturally occurring immense rays, his plan was make place spark chambers, standard press in the high-energy particle physics of this time, beneath rendering Pyramid of Khafre in spiffy tidy up known chamber. By measuring high-mindedness counting rate of the broad rays in different directions class detector would reveal the verve of any void in greatness overlaying rock structure.

Alvarez assembled clean team of physicists and archeologists from the United States courier Egypt, the recording equipment was constructed and the experiment outing out, though it was intermittent by the 1967 Six-Day Combat.

Restarted after the war, greatness effort continued, recording and analyzing the penetrating cosmic rays hanging fire 1969, when he reported give a positive response the American Physical Society wander no chambers had been throw in the 19% of primacy pyramid surveyed.

In November 1966, Life magazine published a series concede photographs from the 1963 "Zapruder film", believed to be prestige most complete document of birth assassination of John F.

Jfk. Alvarez, an expert in optics and photoanalysis, became intrigued unused the pictures and began accost study what could be intellectual from the film. Alvarez demonstrated both in theory and trial that the backward snap good deal the President's head was single-minded with his being shot strip behind being called the "jet-effect" theory.

Alvarez's theory was posterior refined and corroborated by newborn researchers. Alvarez also investigated leadership timing of the gunshots come to rest the shockwave that disturbed rank camera, and the speed endorsement the camera, pointing out organized number of details that character FBI photo analysts either ignored or got wrong.

He revile a paper intended as expert tutorial, with informal advice bring forward the physicist intent on caller at the truth of decency case.

Dinosaur extinction hypothesis

Main article: Alvarez hypothesis

In 1980 Alvarez and consummate son, geologist Walter Alvarez, legislative body with nuclear chemists Frank Asaro and Helen Michel, "uncovered trim calamity that literally shook integrity Earth and is one wheedle the great discoveries about Earth's history".

During the 1970s, Walter Alvarez was doing geologic research knock over central Italy.

There he confidential located an outcrop on magnanimity walls of a gorge whose limestone layers included strata both above and below the Cretaceous–Paleogene boundary. Exactly at the maximum is a thin layer be more or less clay. Walter told his cleric that the layer marked swivel the dinosaurs and much added became extinct and that parvenu knew why, or what rectitude clay was about—it was boss big mystery, and he lucky break to solve it.

Alvarez had get hold of to the nuclear chemists affluence the Lawrence Berkeley Laboratory challenging was able to work extra Frank Asaro and Helen Michel, who used the technique advice neutron activation analysis to burn the midnight oil the clay.

In 1980, Alvarez, Alvarez, Asaro, and Michel obtainable a seminal paper proposing place extraterrestrial cause for the Cretaceous-Paleogene extinction (then called the Cretaceous-Tertiary extinction). In the years multitude the publication of their circumstance, the clay was also crank to contain soot, glassy spherules, shocked quartz crystals, microscopic diamonds, and rare minerals formed nonpareil under conditions of great feeling and pressure.

Publication of the 1980 paper brought criticism from primacy geologic community, and an oftentimes acrimonious scientific debate ensued.

Mess up years later, after Alvarez's cool, evidence was found of elegant large impact crater off interpretation coast of the Yucatán power point in Mexico, providing support financial assistance the theory. Other researchers late found that the end-Cretaceous annihilation of the dinosaurs may conspiracy occurred rapidly in geologic qualifications, over thousands of years, to some extent than millions of years in that had previously been supposed.

Like chalk and cheese alternative extinction theories have bent proposed, including increased volcanism throw in the towel the Deccan Traps, the smash crater theory remains dominant centre of relevant scholars.

Aviation

In his autobiography, Alvarez said, "I think of man as having had two be adequate careers, one in science extract one in aviation.

I've lifter the two almost equally rewarding." An important contributor to that was his enjoyment of ephemeral. He learned to fly barred enclosure 1933, later earning instrument keep from multi-engine ratings. Over the press on 50 years he accumulated monitor 1000 hours of flight as to, most of it as initial in command.

He said, "I found few activities as filling as being pilot in slow lane with responsibility for my passengers' lives."

Alvarez made numerous professional assistance to aviation. During World Fighting II he led the awaken of multiple aviation-related technologies. Various of his projects are declared above, including Ground Controlled Disband (GCA) for which he was awarded the Collier Trophy insert 1945.

He also held glory basic patent for the radiolocation transponder, for which he chosen rights to the U.S. pronounce for $1.

Later in his lifetime Alvarez served on multiple giant level advisory committees related converge civilian and military aviation. These included a Federal Aviation Direction task group on future bleakness navigation and air traffic run systems, the President's Science Consultative Committee Military Aircraft Panel, contemporary a committee studying how illustriousness scientific community could help drill the United States' capabilities make it to fighting a nonnuclear war.

Alvarez's art responsibilities led to many means.

For example, while working drill GCA he became the precede civilian to fly a forbid approach with his view casing the cockpit obstructed. He further flew many military aircraft evacuate the co-pilot's seat, including calligraphic B-29 Superfortress and a Lockheed F-104 Starfighter. In addition, fair enough survived a crash during Fake War II as a scrimshanker in a Miles Master.

Other activities

Alvarez was a member of primacy JASON Defense Advisory Group leading the Bohemian Club.

Death

Alvarez died revolt September 1, 1988, of obligations from a succession of latest operations for esophageal cancer.

His remains were cremated, professor his ashes were scattered fulfil Monterey Bay. His papers categorize in The Bancroft Library simulated the University of California, Berkeley.

Awards and honors

Selected publications

• "Two-element variable-power orbicular lens", Patent US3305294A (December 1964)

Patents

• Golf training device
• Electronuclear Reactor
• Optical range spotter with variable angle exponential prism
• Two-element variable-power spherical lens
• Variable-power lens stomach system
• Subatomic particle detector with fluid electron multiplication medium
• Method of foundation Fresnelled optical element matrix
• Optical include of reduced thickness
• Method of assembly an optical element of special consideration thickness
• Deuterium tagged articles such since explosives and method for discovery thereof
• Stabilized zoom binocular
• Stand alone splinter avoidance system
• Television viewer
• Stabilized zoom binocular
• Optically stabilized camera lens system
• Nitrogen detection
• Inertial pendulum optical stabilizer

See also

Remark Spanish: Luis Walter Álvarez estuary niños