Search for a light $CP$-odd Higgs boson and low-mass dark matter at the Belle experiment

I.S. Seong , S.E. Vahsen , I. Adachi , H. Aihara , S. Al Said , D.M. Asner , V. Aulchenko , T. Aushev , R. Ayad , V. Babu , A.M. Bakich , V. Bansal , P. Behera , V. Bhardwaj , B. Bhuyan , T. Bilka , J. Biswal , A. Bobrov , G. Bonvicini , A. Bozek , M. Bračko , T.E. Browder , L. Cao , D. Červenkov , P. Chang , V. Chekelian , A. Chen , B.G. Cheon , K. Chilikin , K. Cho , Y. Choi , S. Choudhury , D. Cinabro , S. Cunliffe , N. Dash , S. Di Carlo (1) , J. Dingfelder , T.V. Dong , S. Eidelman , D. Epifanov , J.E. Fast , A. Frey , B.G. Fulsom , R. Garg , V. Gaur , N. Gabyshev , A. Garmash , M. Gelb , A. Giri , P. Goldenzweig , B. Golob , E. Guido , J. Haba , K. Hayasaka , H. Hayashii , M.T. Hedges , T. Higuchi , W.-S. Hou , C.-L. Hsu , K. Huang , T. Iijima , K. Inami , G. Inguglia , A. Ishikawa , R. Itoh , M. Iwasaki , Y. Iwasaki , W.W. Jacobs , H.B. Jeon , S. Jia , Y. Jin , D. Joffe , K.K. Joo , T. Julius , A.B. Kaliyar , G. Karyan , T. Kawasaki , H. Kichimi , C. Kiesling , D.Y. Kim , J.B. Kim , K.T. Kim , S.H. Kim , K. Kinoshita , P. Kodyš , S. Korpar , D. Kotchetkov , P. Križan , R. Kroeger , P. Krokovny , T. Kuhr , T. Kumita , A. Kuzmin , Y.-J. Kwon , J.S. Lange , I.S. Lee , S.C. Lee , L.K. Li , Y.B. Li , L. Li Gioi , J. Libby , D. Liventsev , M. Lubej , T. Luo , C. Macqueen , M. Masuda , T. Matsuda , M. Merola , K. Miyabayashi , H. Miyata , R. Mizuk , G.B. Mohanty , T. Mori , R. Mussa , E. Nakano , M. Nakao , T. Nanut , K.J. Nath , M. Nayak , M. Niiyama , N.K. Nisar , S. Nishida , K. Nishimura , S. Ogawa , H. Ono , W. Ostrowicz , P. Pakhlov , G. Pakhlova , B. Pal , H. Park , T.K. Pedlar , R. Pestotnik , L.E. Piilonen , E. Prencipe , M. Ritter , A. Rostomyan , G. Russo , Y. Sakai , M. Salehi , S. Sandilya , L. Santelj , T. Sanuki , V. Savinov , O. Schneider , G. Schnell , J. Schueler , C. Schwanda , Y. Seino , K. Senyo , O. Seon , M.E. Sevior , C.P. Shen , T.-A. Shibata , J.-G. Shiu , F. Simon , E. Solovieva , S. Stanič , M. Starič , M. Sumihama , T. Sumiyoshi , W. Sutcliffe , M. Takizawa , K. Tanida , F. Tenchini , K. Trabelsi , M. Uchida , T. Uglov , Y. Unno , S. Uno , Y. Usov , C. van Hulse , R. van Tonder , G. Varner , A. Vinokurova , A. Vossen , B. Wang , C.H. Wang , P. Wang , M. Watanabe , S. Watanuki , E. Widmann , E. Won , H. Yamamoto , H. Ye , J. Yelton , C.Z. Yuan , Y. Yusa , S. Zakharov , Z.P. Zhang , V. Zhilich , V. Zhukova , V. Zhulanov , A. Zupanc

1 LAL - Laboratoire de l'Accélérateur Linéaire

We report on the first Belle search for a light CP-odd Higgs boson, A0, that decays into low mass dark matter, χ, in final states with a single photon and missing energy. We search for events produced via the dipion transition ϒ(2S)→ϒ(1S)π+π-, followed by the on-shell process ϒ(1S)→γA0 with A0→χχ, or by the off-shell process ϒ(1S)→γχχ. Utilizing a data sample of 157.3×106 ϒ(2S) decays, we find no evidence for a signal. We set limits on the branching fractions of such processes in the mass ranges MA0<8.97  GeV/c2 and Mχ<4.44  GeV/c2. We then use the limits on the off-shell process to set competitive limits on WIMP-nucleon scattering in the WIMP mass range below 5  GeV/c2.

Mots clés: Elementary Particles and Fields; electron positron: annihilation; electron positron: colliding beams; dark matter: mass: low; Higgs particle: electroproduction; Higgs particle: rare decay; dark matter: pair production; Upsilon(10020): hadronic decay; BELLE; KEK-B; Higgs particle: branching ratio: upper limit; missing-energy; off-shell; photon: single production; experimental results; Upsilon(10020) --> Upsilon(9460) pi+ pi-; Upsilon(9460) --> photon Higgs particle; S030DI1

Domaines: Physique des Hautes Energies - Expérience [hep-ex]

I.S. Seong, S.E. Vahsen, I. Adachi, H. Aihara, S. Al Said, et al.. Search for a light $CP$-odd Higgs boson and low-mass dark matter at the Belle experiment. Physical Review Letters, 2019, 122 (1), pp.011801. ⟨10.1103/PhysRevLett.122.011801⟩. ⟨hal-01886168⟩