Jeff Ament, bass player for Pearl Jam, was the victim of a violent mugging outside a recording studio in Atlanta, several sources are reporting. Three people wearing blackmasks, gloves, and pants attacked Ament late last month, according to police records, smashing the windows of a rentedJeep and taking a BlackBerry. They also robbed him of $3,000 in cash and $4,320 worth of goods and his passport. Ament tried to run and was knocked down, sustaining head injuries.The assailants escaped in a black Nissan Maxima. A surveillance camera captured the robbery, but no one has been arrested. Pearl Jam is not commenting.