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EXA 2011 pp 163-167 | Cite as

Neutron bound beta-decay: BOB

  • Josephine McAndrewEmail author
  • Stephan Paul
  • Ralf Emmerich
  • Ralf Engels
  • Peter Fierlinger
  • Mirko Gabriel
  • Erwin Gutsmiedl
  • Johannes Mellenthin
  • Johannes Schön
  • Wolfgang Schott
  • Andreas Ulrich
  • Florian Grüenauer
  • Anton Röhrmoser
Conference paper

Abstract

An experiment to observe the bound beta-decay (BOB) of the free neutron into a hydrogen atom and an electron anti-neutrino is described. The hyperfine spin state population of the monoenergetic hydrogen atom yields the neutrino left-handedness or possible right-handed admixture as well as possible small scalar and tensor contributions to the weak force. The BOB H(2s) hyperfine states can be separated with a Lamb-Shift Spin Filter. These monoenergetic H(2s) atoms are ionised into H by charge exchanging within an argon cell. These ions are then separated using an adaptation of a MAC-E Filter. A first experiment is proposed at the FRMII high thermal-neutron flux beam reactor SR6 through-going beam tube, where we will seek to observe this rare neutron decay-mode for the first time and determine the branching ratio. After successful completion, the hyperfine spin state population will be determined, possibly at the ILL high-flux beam reactor through-going beam tube H6–H7, where the thermal neutron flux is a factor of four larger.

Keywords

Neutron Weak interaction Scalar coupling constant Tensor coupling constant Neutrino helicity 

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Copyright information

© Springer Science+Business Media B.V. 2012

Authors and Affiliations

  • Josephine McAndrew
    • 1
    Email author
  • Stephan Paul
    • 1
  • Ralf Emmerich
    • 1
  • Ralf Engels
    • 2
  • Peter Fierlinger
    • 3
  • Mirko Gabriel
    • 1
  • Erwin Gutsmiedl
    • 1
  • Johannes Mellenthin
    • 1
  • Johannes Schön
    • 1
  • Wolfgang Schott
    • 1
  • Andreas Ulrich
    • 1
  • Florian Grüenauer
    • 1
  • Anton Röhrmoser
    • 4
  1. 1.Physik-DepartmentTUMGarchingGermany
  2. 2.Institut Für KernphysikForschungszentrum JülichJülichGermany
  3. 3.Excellence Cluster UniverseTUMGarchingGermany
  4. 4.FRMIIGarchingGermany

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