Abstract
A search for the narrow structure, X(5568), reported by the D0 Collaboration in the decay
sequence X → B0 π±, B0
→ J/ψφ, is presented. The analysis is based on a data sample
s s
recorded with the ATLAS detector at the LHC corresponding to 4.9 fb−1 of pp collisions at 7 TeV and
19.5 fb−1 at 8 TeV. No significant signal was found. Upper limits on the number of signal events,
with properties corresponding to those reported by D0, and on the X production rate relative to B0
mesons, ρX , were determined at 95% confidence level. The results are N(X) < 382 and ρX < 0.015 for
B0 mesons with transverse momenta above 10 GeV, and N(X) < 356 and ρX < 0.016 for transverse
momenta above 15 GeV. Limits are also set for potential B0 π± resonances in the mass range 5550 MeV
to 5700 MeV.