Showed how helium fuses

Edwin E. Salpeter, 83, an astrophysicist whose work in the “Salpeter-Bethe equation” showed how helium changes to carbon, died of leukemia Tuesday at his home in Ithaca, N.Y., according to Cornell University, where he had been a professor emeritus of physical sciences.

Salpeter attended Cornell in 1949 as a postdoctoral student and spent his career there.

In 1951, he and Cornell theoretical physicist Hans Bethe, winner of the 1967 Nobel Prize in physics, introduced an equation showing how helium nuclei fuse to form carbon in the interiors of ancient stars. Until then, the origin of elements beyond helium in the periodic table was a mystery.

From that work, Salpeter determined the formation rates of stars of various masses in the galaxy.

It remains the basis of studies into the rates of stellar births and deaths.

In 1964, while working independently, Salpeter and Soviet physicist Yakov Zeldovich were the first to propose that a stream of gas falling toward a black hole could be heated to produce detectable X-rays. Thirty years later, data from the Hubble telescope confirmed their idea.

In 1997, Salpeter and Sir Fred Hoyle, a British scientist who coined the term “Big Bang,” shared the $500,000 Crafoord Prize from the Royal Swedish Academy of Sciences for their work in the study of nuclear reactions in stars.

The annual prize marks accomplishments in scientific fields that are not covered by the Nobel Prizes, whose winners also are chosen by the academy.

Born in Vienna on Dec. 3, 1924, Salpeter moved with his family to Australia in 1939. He earned a bachelor’s degree in physics and mathematics at the University of Sydney in 1944 and a doctorate at the University of Birmingham in England in 1948.