Search for the rare decays B-s(0) -> mu(+)mu(-) and B-0 -> mu(+)mu(-)

A search for the decays B-s(0) -> mu(+)mu(-) and B-0 -> mu(+)mu(-) is performed with 0.37 fb(-1) of pp collisions at root s = 7 TeV collected by the LHCb experiment in 2011. The upper limits on the branching fractions are B(B-s(0) -> mu(+)mu(-)) < 1.6 x 10(-8) and B(B-0 -> mu(+)mu(-)) < 3.6 x 10(-9) at 95% confidence level. A combination of these results with the LHCb limits obtained with the 2010 dataset leads to B(B-s(0) -> mu(+)mu(-)) < 1.4 x 10(-8) and B(B-0 -> mu(+)mu(-)) < 3.2 x 10(-9) at 95% confidence level. (C) 2012 CERN. Published by Elsevier B.V. All rights reserved.