Federal authorities bestowed mixed greetings last night on 48 former prisoners of Cuba brought here by Democratic presidential candidate Jesse L. Jackson: they moved to serve arrest warrants on seven of the Americans and to welcome 26 Cubans as potential new citizens.

Jackson arrived at 11:30 p.m. at Dulles International Airport with 22 Americans who had been imprisoned in Cuba for as long as three years on drug trafficking and other criminal charges.

He also brought 26 Cuban political prisoners and an accused CIA agent, most of them jailed since the early 1960s in the aftermath of the Bay of Pigs operation, a CIA-led invasion by Cuban exiles who were routed by Cuban forces.

The prisoners are the fruits of what Jackson called a "moral mission" to help free political captives. The mission drew widely mixed reactions around the country yesterday, including applause from relatives of the freed Americans and skepticism from Cuban-American leaders, who expressed disappointment that only 26 of hundreds of Cuban political prisoners were to be released.

Assistant U.S. Attorney General Stephen Trott of the Justice Department criminal division said at Dulles that seven Americans would be charged with criminal violations and taken to federal and state prisons in this area. He said he would not release the seven names until after the warrants were served.

Those facing only Cuban charges will not be detained, officials said.

Federal immigration officials said the Cubans will be granted temporary entry into the United States, a status that calls for a minimum of paperwork at the airport. They can remain here indefinitely in that status and can apply for asylum, officials said.

"Our desire is to bring them in," White House spokesman Larry Speakes said.

Authorities said that most of the Cubans would go to the homes of families in the United States and that relief agencies plan to provide help in resettlement. They said the Cubans were to spend the night at the St. Charles Hotel on New Hampshire Avenue NW.

The 26 Cubans were given visas by the diplomatic office of the U.S. Interest Section of the Swiss Embassy shortly before leaving Havana.

The Cuban political prisoners, intransigent foes of Cuban President Fidel Castro, are known as "plantados" and have resisted efforts to indoctrinate them in communism. Most have completed 20-year terms for conspiracy and have been held beyond their sentences for refusing political re-education.

The only one with an international reputation is Humberto Noble Alexander, 50, a pastor whose 20-year sentence expired two years ago. He was arrested for preaching the doctrine of original sin, according to Of Human Rights, a group that monitors political prisoners in Cuba.

Alexander has been "a prominent spiritual leader of political prisoners in Havana," according to Thomas White of the human rights group. He said Alexander copied religious hymns onto cigarette paper for other prisoners and made a makeshift pulpit in prison by draping a bedsheet over a board.

The accused CIA agent is Andres Vargas Gomez, grandson of Cuba's 19th-century revolutionary patriot, Maximo Gomez, and a hero to many in the anti-Castro community in the United States. He was imprisoned for 22 years in Cuba on charges of spying for the CIA and was released in December, 1982, but not allowed to leave the country.

The others who were released are not celebrated anti-communists but are well-known among former political prisoners now in Miami, according to Cuban-American groups. Of 17 names of prominent Cuban political prisoners given to Jackson by Cuban-American leaders, only Alexander was among those released.

The Cuban prisoners coming here often staged hunger strikes during their incarceration, according to Amnesty International. Many have refused to wear prison uniforms, insisting on political-prisoner status, and have worn only underwear for several years, several prisoners' rights groups said.

Three of the Cubans were serving 15-year sentences and the others 20-year terms, but all had served beyond their time, according to Of Human Rights. Four are in poor health, according to the group.

Among those released is Jose Agustin Lopez Rodriquez, 62, a railway worker convicted in 1963 of conspiracy against state security and sentenced to 20 years in prison.

According to relatives, he has been denied visits and food parcels since 1979. Although his term has expired, he remained in custody because he refused to accept political re-education, they said.

Another is Francisco Chanes de Armas, 60, jailed in 1961 for "anti-revolutionary activity," according to a relative who said Chanes and his younger brother, Mario, fought with Castro but later changed sides.

Mario, who remains in prison, is well known among exiles because he was part of Castro's expeditionary force that started the Cuban revolution.

"I think these people will be greeted as heroes by the Cuban-American community," said Frank Calzon, Of Human Rights' executive director, referring to the Cuban returnees. "They should be heroes for the democratic world."

The White House and several Cuban-American groups expressed dismay, however, at the small number of Cuban political prisoners released.

"As far as human rights go, we're grateful to Jackson for his efforts," Calzon said. "But he's bringing home a couple of dozen prisoners, and Castro has 5,000 political prisoners. Jackson has convinced Castro to release people who have already completed their prison terms . . . ."

"We feel deceived," said Tomas Regalado, news director of a Spanish radio station in Miami, who said many callers on his talk show expressed anger about the Jackson mission. "We feel that Jesse played to Fidel and Fidel used the human rights issue to gain publicity and improve his image in the United States," Regalado said.

"We regret that not all prisoners held in Cuban jails are being released," Speakes said at the White House. He added that federal officials are checking the Cubans' histories to confirm that they are political prisoners and not criminals, like many who came here in the 1980 "freedom flotilla."

American relatives of the Cuban prisoners have not seen them for years in some cases, and the prospect of their arrival set off strong emotions.

"I'm happy, but I'm thinking of the dead. I'm thinking also of those who are not coming out of prison," said Maria Vargas Gomez, who said she has not seen her husband in 24 years. "I'm thinking also that he is leaving the country and may never go back. So in the middle of all happiness, there is sadness."

She said she does not believe that her husband was a CIA agent.

"Believe me, the CIA wouldn't hire my husband," she said. "He's incapable of mysteries."

Relatives of several returning Americans flew here yesterday, setting the stage for emotional reunions at Dulles. Del. Walter E. Fauntroy (D-D.C.) and Mayor Marion Barry joined a crowd of Jackson supporters who welcomed the candidate and his entourage. Jackson met briefly with about 25 relatives of the returning prisoners and was greeted with rousing applause.

In interviews, families told of widely varying circumstances that led to the arrest of sons and fathers, most convicted of illegal entry into Cuba and drug trafficking. U.S. officials said some may have been forced to confess to crimes they did not commit.

Robert Dana Johnson, 28, of North Miami, strayed into Cuban waters while on a scuba-diving trip out of Miami, according to his sister, Darla Wertz. Cuban authorities allegedly found almost 300 pounds of marijuana aboard, a charge denied by Johnson and his three companions.

Johnson and his companions--Jerry Lee Jacoby, 33; Richard Michael Mazura, 30; and Robert Young, 34--were charged with illegal entry into Cuban waters and drug trafficking, according to Johnson's family.

Mark Ely Jr., 27, a charter pilot from Miami, was arrested in September, 1981, after his plane was forced to land in Cuba in bad weather en route home from Jamaica, according to his brother, Michael. The Cubans charged that 400 pounds of marijuana were on Ely's plane, but Ely denied this, his brother said.

Calvin Privette, 29, a Newport News, Va., electrician, was arrested two years ago when he and two other men strayed into Cuban waters while on a fishing trip to Colombia, according to his relatives.

Privette's family was quoted in news reports as saying Cuban authorities charged that he was attempting to smuggle 5,000 pounds of marijuana. They said he denies it.

Elbert Larry Cheatham, 44, a plumber from Williamsburg, Va., and Clarence Warner Elbourn, 47, of Lexena, Va., were arrested in April, 1983, after their boat drifted into Cuban waters, according to Sunny Seitler, an acquaintance. Both were charged with drug trafficking. Americans Released Andres Vargas Gomez, 69, of Miami John Bays, 23, of Chicago Ignacio Castellano Jr., 23, of Key West, Fla. Elbert Larry Cheatham, 44, of Williamsburg, Va. James Martin Decker, 32, of Detroit Clarence Warner Elbourn, 47, of Lexena, Va. Mark Ely Jr., 27, of Miami Fred Harding, 47, of Taunton, Mass. David Hudson, 28, of Prescott, Ariz. Jerry Lee Jacoby, 33, of Miami Robert Dana Johnson, 28, of North Miami John L. Marker, 62, of St. Petersburg, Fla. Richard Michael Mazura, 30, of New York City Leslie McElveen, 37, of Miami Julian Medina Rodriguez, 60, of Cabo Rojo, Puerto Rico Omar Juan Ortega, 21, of Miami Jose Poyo, 30, of Bogota, Colombia Calvin Privette, 29, of Newport News, Va. Lawrence Reiher, 30, of Miami Felix Rodriguez, 48, of Cabo Rojo, Puerto Rico Alan Snyder, 24, of Sweetwater, Tenn. William Wickett, 38, of Miami Robert Young, 34, of East St. Louis, Ill. Cubans Released Conrad Aguirre, 68 Juan Francisco Valdes Camejo, 51 Jesus Peres Cruz, 46 Gilberto Conde Otero, 53 Jose Jarpe Jarpe, 57 Armando Yong Martinez, 42 Basilio Guzman Marrero, 47 Aristides Perez Montanez, 49 Eladio Ruiz Sanchez, 59 Cleto Perez Barrios, 57 Wilfredo Martinez Roque, 37 Juan Gonzalez Ruiz, 45 Daniel Conde Freire, 43 Rene Ramos Gonzalez, 45 Gerardo Martinez Perez, 58 Luis Felipe Lara Gallo, 62 Humberto Noble Alexander, 50 Jose Agustin Lopez Rodriquez, 62 Francisco Chanes de Armas, 60 Jesus Santana Alvarez, 51 Rolando Garcia Fuentes, 50 Rafael Trujillo Pacheco, 46 Clemente Rodriguez Isla, 55 Jose Rolando Otero Sabatier, 66 Juan e Armas Laborde, 58 Esturnio Mesa Schumann, 53.