PT Journal AU ATLAS Collaboration (Aaboud, Mea Alvarez Piqueras, D Barranco Navarro, L Cabrera Urban, S Castillo Gimenez, V Cerda Alberich, L Costa, MJ Fernandez Martinez, P Ferrer, A Fiorini, L Fuster, J Garcia, C Garcia Navarro, JE Gonzalez de la Hoz, S Hernandez Jimenez, Y Higon-Rodriguez, E Jimenez Pena, J King, M Lacasta, C Lacuesta, VR Mamuzic, J Marti-Garcia, S Melini, D Mitsou, VA Pedraza Lopez, S Rodriguez Rodriguez, D Romero Adam, E Ros, E Salt, J Sanchez Martinez, V Soldevila, U Sanchez, J Valero, A Valls Ferrer, JA Vos, M TI Search for the Higgs boson produced in association with a W boson and decaying to four b-quarks via two spin-zero particles in pp collisions at 13 TeV with the ATLAS detector SO European Physical Journal C JI Eur. Phys. J. C PY 2016 BP 605 - 31pp VL 76 IS 11 DI 10.1140/epjc/s10052-016-4418-9 LA English AB This paper presents a dedicated search for exotic decays of the Higgs boson to a pair of new spin-zero particles, H -> aa, where the particle a decays to b-quarks and has a mass in the range of 20-60 GeV. The search is performed in events where the Higgs boson is produced in associationwith aW boson, giving rise to a signature of a lepton (electron or muon), missing transverse momentum, and multiple jets from b-quark decays. The analysis is based on the full dataset of pp collisions at root s = 13 TeV recorded in 2015 by theATLAS detector at theCERNLargeHadron Collider, corresponding to an integrated luminosity of 3.2 fb(-1). No significant excess of events above the Standard Model prediction is observed, and a 95% confidence-level upper limit is derived for the product of the production cross section for pp -> WH times the branching ratio for the decay H -> aa -> 4b. The upper limit ranges from 6.2 pb for an a-boson mass m(a) = 20 GeV to 1.5 pb for m(a) = 60 GeV. ER