A right-wing group's assertion that the Holocaust never happened was dismissed today by a Los Angeles County Superior Court judge.

"It is not reasonably subject to dispute," said Judge Thomas T. Johnson.

On the day after Yom Kippur, the Jewish day of atonement, Jews crowded the Judge Johnson's courtroom and celebrated the decision with hugs for Mel Mermelstein, who lost his mother and two sisters at the World War II concentration camp called Auschwitz and who sued the Institute for Historical Review for $17 million.

The judge said, "The court does take judicial notice that Jews were gassed to death in Poland at Auschwitz in the summer of 1944," when Mermelstein and his family were there. The judge brushed aside a request by Richard Fusilier, attorney for the institute, for specific evidence of what has come to be called the Holocaust.

Johnson said he would rule later on whether the institute must pay Mermelstein any money, but today's decision rules out a court hearing on the institute's contention that the Holocaust is a hoax.

The institute, with 11 persons holding doctorate degrees on the editorial advisory board of its "Journal of Historical Review," has argued that, although millions of Jews were arrested by the Nazis before and during World War II, they died of disease, malnutrition and Allied bombing, not through any planned extermination campaign. When the institute declined to pay Mermelstein the $50,000 prize it offered for proof of the gas chambers' existence, he sued.

"I feel relieved," said Mermelstein, 54, a Long Beach businessman. "But I wonder why I should feel that way, because it is an established fact." He said he hoped the institute would drop its efforts to debunk the Holocaust, but the former publisher of the Journal of Historical Review, David McCalden, appeared undeterred by Mermelstein's efforts.

McCalden, who has used the pen name Lewis Brandon, has sent out a form letter advertising the "David McCalden Revisionist Newsletter" at a $200 annual subscription fee.

In the letter, he boasts of press coverage he has secured for the institute, and says, "I am the man who dreamt up the entire idea." McCalden offers the latest news on attempts to disprove the Holocaust, along with interviews with "Revisionist liberals, Revisionist Jews, Revisionist anarchists . . . ."

McCalden has argued that the figure of 6 million Jews killed in the German concentration camps, generally accepted by historians in the last 30 years, is wrong. He estimates that 350,000 died in captivity, and that the rest were expelled to Russia, Madagascar, Palestine and other places.

The founder of the institute is Willis Carto, treasurer of the Washington-based, right-wing Liberty Lobby. William Cox, Mermelstein's attorney, submitted an enormous brief that argues that the institute is "but one arm of an organized, nationwide campaign of anti-Semitism and racism" designed to make Carto leader of all North America and Europe.

Cox today called Johnson's simple ruling a victory, and the lawyer for the institute, Fusilier, agreed. He said that, although he felt he should represent his client's point of view, he tended to believe Mermelstein, and had been in the American armed forces that liberated the concentration camp at Dachau.

Cox said Johnson is expected to rule within two weeks on whether Mermelstein is entitled to the $50,000 prize or the additional damages, now reduced to $1 million, for breach of contract and "injurious denial of established fact."