FORT HOOD, Texas -- Survivors of the 2009 shooting rampage at Fort Hood and relatives of those killed testified Monday during the final phase of Maj. Nidal Hasan's trial.

Prosecutors hope the emotional testimony -- from sobbing widows, distraught parents and paralyzed soldiers -- helps convince jurors to impose a rare military death sentence on Hasan, who was convicted last week of killing 13 people and wounding more than 30 others at the Texas military base.

The sentencing phase also will be Hasan's last chance to tell jurors what he's spent the last four years telling the military, judges and journalists: that the killing of unarmed American soldiers preparing to deploy to Iraq and Afghanistan was necessary to protect Muslim insurgents. But whether he plans to address jurors remains unclear.

Staff Sgt. Patrick Ziegler was among the first to testify, telling jurors how he was shot four times and underwent emergency surgery that removed about 20 per cent of his brain. Doctors initially expected him to die or remain in a vegetative state.

Shoua Her wiped away tears as she recalled how she and her husband, Pfc. Kham Xiong, talked about growing old together and having more children. Now, she said, their children know their slain father only through memories and stories.

"We had talked about how excited we were to purchase our first home. We talked about vacations and places we wanted to go visit. And all that was stripped away from me," she said.

As she testified, one juror, a male officer, fought back tears.

The hearing ended for the day after a dozen people testified. Hasan asked for three recesses through the day, and the judge granted two of them.

Other widows, mothers, children and siblings of the slain also are expected this week to tell the jury of 13 high-ranking military officers about their loves ones and describe the pain of living without them.

What they won't be allowed to talk about are their feelings toward Hasan or what punishment they think he deserves.

Hasan, an American-born Muslim, has admitted carrying out the attack and showed no reaction when he was found guilty. He is representing himself during his trial, yet he called no witnesses, declined to testify and questioned only three of prosecutors' nearly 90 witnesses before he was convicted.

Earlier Monday, the judge asked Hasan if he wanted to continue representing himself and advised against it, as she has repeatedly done during the trial.

"You understand that this is the stage of trial ... you are staking your life on decisions you make. You understand?" the judge, Col. Tara Osborn, asked.

"I do," Hasan said.

She told him that it was "unwise to represent yourself, but it's your choice."

At the minimum, the 42-year-old Hasan will spend the rest of his life in prison.

Prosecutors want Hasan to join just five other U.S. service members currently on military death row. No American soldier has been executed since 1961. Many military death row inmates have had their sentences overturned on appeal, which are automatic when jurors unanimously vote for the death penalty. The U.S. president must eventually approve a military death sentence.