The 50-mile-long Panama Canal celebrated the opening of a $5.4 billion expansion that will allow larger ships to pass at greater volumes. The work had focused on increasing capacity at two sets of locks, one at either end of the canal. A Chinese-owned container ship, Cosco Shipping Panama, was the first commercial vessel to cross through Caribbean-facing Agua Clara locks on Sunday, amid scenes of jubilation in Panama. The new locks are wider and deeper than their predecessors. Officials say the larger locks and a new lane will double the canal’s cargo capacity. The canal initially opened more than 100 years ago and could handle ships carrying about 5,500 cargo containers. With the expansion, it can handle more than 13,000.