A former Florida college professor, Sami Al-Arian, has pleaded guilty to aiding Palestinian Islamic Jihad and agreed to serve more jail time before being deported from America, according to records made public yesterday by a federal court in Tampa.

Judge James Moody Jr. formally accepted Al-Arian’s plea yesterday to one count of conspiracy to assist a designated terrorist entity. Prosecutors and Al-Arian agreed that he should be sentenced to between 46 and 57 months’ incarceration. Judge Moody has agreed to impose a sentence in that range at a hearing he set for May 1.

The former University of South Florida professor was arrested in February 2003 and accused of being Palestinian Islamic Jihad’s leader in America. He has been in custody ever since and is eligible, under federal law, to credit for time served and a reduction for “good time.”

If Judge Moody agrees the prosecutors’ recommendation that Al-Arian receive a sentence at the low end of the range, his release and deportation could come as soon as June. The plea agreement does not specify where the Kuwaiti-born professor would be sent after completing his sentence, but does stipulate that he will not be deported to Canada or Mexico.

Al-Arian and three co-defendants were put on trial last year. A jury heard evidence for six months before acquitting the former computer engineering professor on eight counts. Jurors could not reach agreement on nine other counts. The jury also failed to reach a verdict on eight counts against another defendant, Hatem Fariz. The remaining two defendants at the trial, Sameeh Hammoudeh and Ghassan Ballut, were acquitted on all charges. Hammoudeh is also awaiting deportation.

The government signaled earlier this year that it was preparing to retry Al-Arian, but has agreed to drop the remaining charges against Al-Arian when he is sentenced.

As part of the plea deal, Al-Arian admitted to a variety of facts about his support for Palestinian Islamic Jihad, a terrorist group responsible for killing dozens of people in Israel, Gaza, and the West bank, chiefly through suicide bombings. In the agreement, Al-Arian conceded that he “was associated with” and “performed services for” Palestinian Islamic Jihad.

Those admissions go somewhat beyond his attorney’s concession during the trial that Al-Arian had “an affiliation” with the terrorist group. However, the agreement does not match the claims of prosecutors during the trial that he was a member and leader of the organization.

“We have a responsibility not to allow our nation to be a safe haven for those who provide assistance to the activity of terrorists,” Attorney General Gonzales said in a written statement. “Sami Al-Arian has already spent significant time behind bars and will now lose the right to live in the country he calls home as a result of his confessed criminal conduct on behalf of the Palestinian Islamic Jihad, which is the same conduct he steadfastly denied in public statements over the last decade.”

An attorney for Al-Arian, Linda Moreno, did not return a call seeking comment for this article.

Al-Arian is not an American citizen, but holds permanent resident status, also known as a green card. In the plea deal, he conceded that he knew that several men who worked for his think tank, the World & Islam Studies Enterprise, were also associated with Palestinian Islamic Jihad. The professor long maintained that the men, Ramadan Shallah, Bashir Nafi, and Mazen Al-Najjar, had no ties to the group. One fact admitted to in the plea agreement is that Al-Arian lied to a St. Petersburg Times reporter about Mr. Shallah’s affiliations after he abruptly left America and was named as secretary-general of Islamic Jihad. The lies to the reporter were also conceded at trial by one of Al-Arian’s defense lawyers, William Moffitt.

The plea agreement stipulates that Al-Arian “was aware that the PIJ achieved its objectives by, among other means, acts of violence.” The professor, who initialed each page of the deal, also admitted to conversations using code words such as “ten shirts” and “the magazines” to refer to sums of money transferred to alleged participants in the conspiracy. Efforts Al-Arian made to defeat deportation of his brother-in-law, Mr. Al-Najjar, are also described in the plea as part of services to the terrorist group.

A spokesman for a Muslim group that was sharply critical of the prosecution, the Council on American-Islamic Relations, said his organization had a mixed reaction to Al-Arian’s plea. “It’s bittersweet,” the spokesman, Ahmed Bedier, said in an interview. “He has to leave the country but also he was victorious in his trial.”

Asked about Al-Arian’s admissions of involvement with Palestinian Islamic Jihad, Mr. Bedier said, “He’s not saying he’s guilty of providing support to PIJ. He provided support to associates of PIJ.” The spokesman said the plea was a product of the government’s desire to “save face” and Al-Arian’s desire to be reunited with his family after three years of separation. “By his own choice, he compromises, in part so he can just go on with his life and his family,” Mr. Bedier said. He scoffed at the concession in the plea deal that Al-Arian lied to a reporter. “Since when is lying to a reporter or hiding stuff from a reporter considered to be terrorism?” he asked.

A New Jersey man whose daughter was killed in a Palestinian Islamic Jihad bombing in Gaza in 1995, Stephen Flatow, said the plea is not an outright victory for either Al-Arian or the prosecution. “Both sides are not happy,” Mr. Flatow said. However, he said the resolution sullies Al-Arian’s reputation. “I don’t think Sami Al-Arian can walk out of prison, before he gets on an airplane, with his head held high. He’s been taken down a peg,” Mr. Flatow said.

The plea agreement was signed with prosecutors in February and kept under wraps. Al-Arian formally offered the plea to a federal magistrate, Thomas McCoun, at a secret court hearing on Friday. The magistrate recommended that Judge Moody accept the plea, and he did so in an order issued today.

In a statement, the Justice Department said it objected to the exclusion of the public from Friday’s plea hearing, but the objection was overruled.