Long-range pseudorapidity dihadron correlations in d + Au collisions at √s[subscript NN] = 200 GeV

Abstract

Dihadron angular correlations in d + Au collisions at √s[subscript NN] = 200 GeV are reported as a function of the measured zero-degree calorimeter neutral energy and the forward charged hadron multiplicity in the Au-beam direction. A finite correlated yield is observed at large relative pseudorapidity (Δη) on the near side (i.e. relative azimuth Δϕ~0). This correlated yield as a function of Δη appears to scale with the dominant, primarily jet-related, away-side (Δϕ~π) yield. The Fourier coefficients of the Δϕ correlation, V[subscript n] = 〈cos⁡nΔϕ〉, have a strong Δη dependence. In addition, it is found that V[subscript 1] is approximately inversely proportional to the mid-rapidity event multiplicity, while V[subscript 2] is independent of it with similar magnitude in the forward (d-going) and backward (Au-going) directions.