#: 283 S0/EasyPlex 06-Sep-88 14:09 MST Sb: APn 09/02 0331 Obit-Alvarez Fm: Executive News Svc. [72135,424] Copyright, 1988. The Associated Press. All rights reserved. The information contained in this news report may not be republished or redistributed without the prior written authority of The Associated Press. BERKELEY, Calif. (AP) -- Nobel Prize-winner Luis W. Alvarez, a brilliant, wide-ranging physicist who helped develop the atomic bomb and a controversial theory that asteroids or comets wiped out the dinosaurs, has died at age 77. Alvarez died at his home in this San Francisco Bay college town late Wednesday after a long battle with cancer, it was announced Thursday. Colleagues described Alvarez as a scientific Renaissance man whose colorful career took him from wartime radar systems to UFO sightings, secrets of an Egyptian pyramid and an analysis of the assassination of President Kennedy. "Luis Alvarez was a stunningly creative individual," David A. Shirley, director of Lawrence Berkeley Laboratory, said Thursday. "His discoveries and inventions spanned an amazing range of the frontiers of man's knowledge over more than half a century." Alvarez, who worked at the laboratory and the University of California, died of complications from operations for esophageal cancer, laboratory spokeswoman Mary Barberia said, quoting the physicist's widow, Janet. His health had declined since surgery for a benign brain tumor last fall, the spokeswoman said. Alvarez won the Nobel Prize in physics in 1968 for developing the liquid-hydrogen bubble chamber and for discovering numerous atomic particles with the device. The chamber is filled with a transparent liquid so that charged particles and their collisions can be studied by photographing the bubbles and boiling that occur along their paths. In the late 1970s, Alvarez made headlines with the theory that asteroids or comets striking the Earth 65 million years ago killed the dinosaurs by kicking up huge, dense clouds of dust and smoke. Alvarez and colleagues who developed the hypothesis, including his geologist son Walter, argued that the clouds blocked sunlight, lowering temperatures, destroying food plants, and resulting in the extinction of dinosaurs and many other species. The theory, which challenged the long-held view that dinosaurs were unsuited for survival in the Darwinian evolutionary scheme, triggered a bitter scientific debate that continues to this day. Others argue that volcanic eruptions killed the dinosaurs by darkening the sun. Alvarez labeled one critic "a weak sister," and accused others of "publishing scientific nonsense." His theory got a boost last week when new evidence from a study of ancient clay was reported in the British journal Nature. The hypothesis has a chilling modern-day counterpart: a theory that that an atomic war would produce enough smoke to plunge Earth into a cold, dark "nuclear winter" that would wipe out any survivors. Alvarez, a San Francisco native, was the son of Walter C. Alvarez, a noted physician and medical columnist at the Mayo Clinic in Rochester, Minn. He wrote in his 1987 autobiography, "Alvarez, Adventures of a Physicist" that he was indebted to his father, who told him it was a good idea to take a night off now and then to do nothing but think. As an undergraduate at the University of Chicago, Alvarez built one of the first Geiger counters in the United States. As a graduate student, he used it to study cosmic rays and proved radiation from space consists mostly of protons. He began working at Berkeley in 1936. His discoveries included the capture of electrons by atomic nuclei and the radioactivity of tritium, an isotope of hydrogen used in thermonuclear weapons. During World War II, Alvarez invented an effective bomb sight and a number of radar systems. His invention of a ground-controlled approach landing system saved the lives of many Allied pilots, some of whom thanked him after the war, according to California-Berkeley. Alvarez played an important role in developing the atomic bomb, and invented several types of atom smashers. In his autobiography, he nostalgically recalled the early days of atomic research, when he held a sphere of radioactive plutonium in his hands, "feeling its warmth." Alvarez made news by applying physics to popular subjects, including the X-ray scan of an Egyptian pyramid for hidden chambers -- there were none -- and analysis of evidence in the Kennedy assassination. His findings supported the Warren Commission's conclusion that Lee Harvey Oswald was the lone assassin. University of California President David P. Gardner said Thursday that he and the entire university community were saddened by the death of Alvarez, whom he called "a creative and energetic scientist." Gardner said Alvarez showed "concern for the student, commitment to meaningful and distinctive research, and devotion to the betterment of society. `He will be missed." Alvarez is survived by his wife, Janet, two sons, two daughters, two sisters and a brother. Action