Physics Letters B (Dec 2014)

Charge symmetry breaking in dd→He4π0 with WASA-at-COSY

  • P. Adlarson,
  • W. Augustyniak,
  • W. Bardan,
  • M. Bashkanov,
  • F.S. Bergmann,
  • M. Berłowski,
  • H. Bhatt,
  • A. Bondar,
  • M. Büscher,
  • H. Calén,
  • I. Ciepał,
  • H. Clement,
  • D. Coderre,
  • E. Czerwiński,
  • K. Demmich,
  • E. Doroshkevich,
  • R. Engels,
  • A. Erven,
  • W. Erven,
  • W. Eyrich,
  • P. Fedorets,
  • K. Föhl,
  • K. Fransson,
  • F. Goldenbaum,
  • P. Goslawski,
  • A. Goswami,
  • K. Grigoryev,
  • C.-O. Gullström,
  • C. Hanhart,
  • F. Hauenstein,
  • L. Heijkenskjöld,
  • V. Hejny,
  • B. Höistad,
  • N. Hüsken,
  • L. Jarczyk,
  • T. Johansson,
  • B. Kamys,
  • G. Kemmerling,
  • F.A. Khan,
  • A. Khoukaz,
  • D.A. Kirillov,
  • S. Kistryn,
  • H. Kleines,
  • B. Kłos,
  • W. Krzemień,
  • P. Kulessa,
  • A. Kupść,
  • A. Kuzmin,
  • K. Lalwani,
  • D. Lersch,
  • B. Lorentz,
  • A. Magiera,
  • R. Maier,
  • P. Marciniewski,
  • B. Mariański,
  • M. Mikirtychiants,
  • H.-P. Morsch,
  • P. Moskal,
  • H. Ohm,
  • I. Ozerianska,
  • E. Perez del Rio,
  • N.M. Piskunov,
  • P. Podkopał,
  • D. Prasuhn,
  • A. Pricking,
  • D. Pszczel,
  • K. Pysz,
  • A. Pyszniak,
  • C.F. Redmer,
  • J. Ritman,
  • A. Roy,
  • Z. Rudy,
  • S. Sawant,
  • S. Schadmand,
  • T. Sefzick,
  • V. Serdyuk,
  • B. Shwartz,
  • R. Siudak,
  • T. Skorodko,
  • M. Skurzok,
  • J. Smyrski,
  • V. Sopov,
  • R. Stassen,
  • J. Stepaniak,
  • E. Stephan,
  • G. Sterzenbach,
  • H. Stockhorst,
  • H. Ströher,
  • A. Szczurek,
  • A. Täschner,
  • A. Trzciński,
  • R. Varma,
  • M. Wolke,
  • A. Wrońska,
  • P. Wüstner,
  • P. Wurm,
  • A. Yamamoto,
  • L. Yurev,
  • J. Zabierowski,
  • M.J. Zieliński,
  • A. Zink,
  • J. Złomańczuk,
  • P. Żuprański,
  • M. Żurek

Journal volume & issue
Vol. 739
pp. 44 – 49

Abstract

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Charge symmetry breaking (CSB) observables are a suitable experimental tool to examine effects induced by quark masses on the nuclear level. Previous high precision data from TRIUMF and IUCF are currently used to develop a consistent description of CSB within the framework of chiral perturbation theory. In this work the experimental studies on the reaction dd→He4π0 have been extended towards higher excess energies in order to provide information on the contribution of p-waves in the final state. For this, an exclusive measurement has been carried out at a beam momentum of pd=1.2 GeV/c using the WASA-at-COSY facility. The total cross section amounts to σtot=(118±18stat±13sys±8ext) pb and first data on the differential cross section are consistent with s-wave pion production. Keywords: Charge symmetry breaking, Deuteron–deuteron interactions, Pion production