Has saturation physics been observed in deuteron-gold collisions at RHIC?

Baier R, Mehtar-Tani Y, Schiff D. Has saturation physics been observed in deuteron-gold collisions at RHIC? NUCLEAR PHYSICS A. 2006;764:515-527.In the framework of the recently proposed saturation picture, we examine in a systematic way whether the nuclear modification factor measured for d-Au collisions at RHIC may be simply explained. The Cronin peak which is obtained at mid-rapidity around k(perpendicular to) similar or equal to 3 GeV may be reproduced at the proper height only by boosting the saturation momentum by an additional nuclear component as already shown in the literature. In this respect, mid-rapidity RHIC data cannot necessarily he seen as a probe of the saturation picture. The large rapidity (eta similar or equal to 3) region allows us to test the shape of the unintegrated gluon distribution in the nucleus, investigating various parameterizations inspired by large rapidity solutions (of the BFKL and) of the Balitsky-Kovchegov (BK) equation. A satisfactory description of R-CP at RHIC is obtained in the BK Picture. (c) 2005 Elsevier B.V. All rights reserved