A judge said retired geologist Jim Fitton acted with criminal intent when he tried to leave the country with the fragments. Fitton said he didn't know his actions were unlawful.
Troops and patrols have deployed around Baghdad following the attack with armed drones that targeted Prime Minister Mustafa al-Kadhimi in his residence.
The Iraqi government says Prime Minister Mustafa al-Kadhimi has survived an assassination attempt with an armed drone and is unharmed.
Iraqis have voted in parliamentary elections held months ahead of schedule as a concession to a youth-led uprising against corruption and mismanagement.
Among the dead were at least 28 patients on ventilators battling severe symptoms of the coronavirus.
Pope Francis brushed aside the coronavirus pandemic and security concerns to make his first-ever papal visit to the country.
One of the rockets struck close to the American Embassy. The attack signals an end to an informal truce announced by Iran-backed militias in October.
Tehran accuses Trump and 35 others of involvement in the January drone strike that killed Gen. Qassem Soleimani in Baghdad.
The airstrikes came just hours after an attack killed and wounded American and British servicemen at a base north of Baghdad.
Hundreds of anti-government demonstrators flooded the streets of Baghdad and Iraq's southern provinces on Sunday.