PHOENIX » Jodi Arias spent 18 days on the stand sharing intimate, emotional and oftentimes X-rated details of her life before a rapt television and online audience. She had hoped it all might convince a jury that she killed her one-time boyfriend in self-defense.

But the eight men and four women on the panel didn’t buy it, convicting Arias of first-degree murder after only about 15 hours of deliberations. Jurors will return to court Thursday to begin the next phase of the trial that could set the stage for Arias receiving a death sentence — a penalty she, herself, said she now desires in a stunning interview following her conviction.

Minutes after being convicted, Arias said she was overwhelmed and surprised because she didn’t believe she committed first-degree murder.

"It was unexpected for me, yes, because there was no premeditation on my part," she told Fox affiliate KSAZ in the courthouse. Arias added she would "prefer to die sooner than later," rather than spending the rest of her life in prison.

The case elevated the unknown waitress and aspiring photographer to a household name, with a real-life story of love, betrayal and murder far more alluring than any made-for-TV movie. The crime itself was enough to grab headlines: Arias, a 32-year-old high school dropout, shot Travis Alexander in the forehead, stabbed him nearly 30 times and slit his throat from ear to ear, leaving the motivational speaker and businessman nearly decapitated.

She claimed he attacked her and she fought for her life. Prosecutors said she killed out of jealous rage after Alexander wanted to end their affair and planned to take a trip to Mexico with another woman.

Arias’ four-month trial quickly became a media sensation — ratings gold for cable networks that could broadcast from inside the courtroom and feed an insatiable public appetite for true-crime drama delivered live and up-close. It was, for many, the horrible train wreck they just couldn’t turn away from, even though they know they should.

Arias fought back tears as the verdict was announced Wednesday in the hushed, packed courtroom, while Alexander’s family members wept and hugged each other. They wore blue ribbons and wristbands with the words "Justice For Travis." The family thanked prosecutor Juan Martinez and a key witness and said it appreciated the outpouring of support from the public.

Outside, a huge crowd that had gathered on the courthouse steps screamed, whistled and cheered the news in a case that has attracted fans from across the country who traveled to Phoenix to be close to the proceedings. Some chanted, "USA, USA, USA!"

Alexander’s friend Chris Hughes said he was happy with the verdict, pointing out a bold proclamation that Arias made in one of her jailhouse interviews that she wouldn’t be found guilty.

"She said, ‘No jury would convict me. Mark my words.’ This jury convicted her," Hughes said. "Luckily we had 12 smart jurors. They nailed it."

When asked about Alexander’s family, Arias said in her TV interview, "I just hope that now that a verdict has been rendered, that they’ll be able to find peace."

Arias said she doesn’t have access to the Internet in jail so she’s been reading newspapers. She also told the station (http://bit.ly/15qG7aP) other inmates have wanted to shake her hand, give her a hug or get her autograph.

Testimony in Arias’ trial began in early January. The trial quickly snowballed into a made-for-the-tabloids drama, garnering daily coverage from cable news networks and spawning a virtual cottage industry for talk shows, legal experts and even Arias, who used her notoriety to sell artwork she made in jail.

The Maricopa County Sheriff’s Office said no more media interviews with Arias will be granted. She has been placed on suicide watch.

The trial now moves into the so-called aggravation phase during which prosecutors will argue the killing was committed in an especially cruel, heinous and depraved manner that should allow jurors to consider the death penalty. Both sides may call witnesses and show evidence. If the panel finds the aggravating factors exist, the trial then moves into the final penalty phase during which jurors will recommend either life in prison or death.

Authorities said Alexander fought for his life as Arias attacked him in a blitz, but he soon grew too weak to defend himself.

"Mr. Alexander did not die calmly," prosecutor Juan Martinez told jurors in opening statements.

Arias said she recalled Alexander attacking her in a fury after a day of sex. She said Alexander came at her "like a linebacker," body-slamming her to the tile floor. She managed to wriggle free and ran into his closet to retrieve a gun he kept on a shelf. She said she fired in self-defense but had no memory of stabbing him.

She acknowledged trying to clean the scene of the killing, dumping the gun in the desert and working on an alibi to avoid suspicion. She said she was too scared and ashamed to tell the truth. However, none of Arias’ allegations that Alexander had physically abused her in the months before his death, that he owned a gun and had sexual desires for young boys, were corroborated by witnesses or evidence during the trial. She acknowledged lying repeatedly before and after her arrest but insisted she was telling the truth in court.

Arias spent 18 days on the witness stand describing an abusive childhood, cheating boyfriends, dead-end jobs, a shocking sexual relationship with Alexander, and her contention that he had grown physically violent.

Psychologist Richard Samuels testified for the defense that Arias suffered from post-traumatic stress disorder and dissociative amnesia, which explained why she couldn’t recall much from the day of the killing. Another defense witness, psychotherapist Alyce LaViolette, concluded that Arias was a battered woman.

Their testimony was crucial and aimed at convincing jurors that, one, Arias wasn’t lying about her memory gaps from the day of the killing, and two, that she did suffer physical abuse by Alexander. Defense attorneys had to get jurors to believe that despite no evidence of Alexander ever having been violent in the past, he had attacked Arias on several occasions, and did so again on the day of his death.

After all, there was no dispute that Arias killed Alexander.

It was the first thing Arias’ defense acknowledged as the trial began.

"Jodi Arias killed Travis Alexander," Arias attorney Jennifer Willmott told jurors in opening statements. "There is no question about it. The million-dollar question is what would have forced her to do it?"

Martinez worked feverishly to attack the credibility of the defense experts, accusing them of having sympathy for Arias and offering biased opinions.

Aside from her lies, Arias had another formidable obstacle to overcome.

Her grandparents had reported a .25-caliber handgun stolen from their Northern California home about a week before Alexander’s death — the same caliber used to shoot him — but Arias insisted she didn’t take it. Authorities believe she brought it with her to kill him. The coincidence of the same caliber gun stolen from the home also being used to shoot Alexander was never resolved.

Meanwhile, the entire case devolved into a circus-like spectacle attracting dozens of enthusiast each day to the courthouse as they lined up for a chance to score just a few open public seats in the gallery. One trial regular sold her spot in line to another person for $200. Both got reprimands from the court, and the money was returned.

Many people also gathered outside after trial for a chance to see Martinez, who had gained celebrity-like status for his firebrand tactics and unapologetically intimidating style of cross-examining defense witnesses.

The case grew into a worldwide sensation as thousands followed the trial via a live, unedited Web feed. Twitter filled with comments as spectators expressed their opinions on everything from Arias’ wardrobe to Martinez’s angry demeanor. For its fans, the Arias trial became a live daytime soap opera.

Adding to the spectacle, Arias sold drawings from jail throughout the trial on a website operated by a third party, Arias’ mother said. According to the site, some pieces were fetching more than $1,000, and Sandra Arias said the money was being used to help pay for family expenses. Nothing prevented Jodi Arias from profiting from her notoriety given she hadn’t been convicted of a crime.