Event Characterization Detectors

Beam-Beam CountersMeasures collision location and centrality. Starts the stopwatch for an event.
Zero Degree Calorimeters and Shower Max DetectorsMeasures collision location and centrality.
Forward CalorimetersFor d+Au collisions, it measures surviving neutrons and protons from the original deuteron.
Multiplicity Vertex DetectorMeasures collision location and charged particle distributions.
Reaction Plane DetectorAccurately measures the reaction plane of each collision.