A hybrid setup for fundamental unknowns in neutrino oscillations using T2HK (ν) and μ-DAR \( \left(\overline{\nu}\right) \)

  • Sanjib Kumar AgarwallaEmail author
  • Monojit Ghosh
  • Sushant K. Raut
Open Access
Regular Article - Theoretical Physics


Neutrino mass hierarchy, CP-violation, and octant of θ 23 are the fundamental unknowns in neutrino oscillations. In order to address all these three unknowns, we study the physics reach of a setup, where we replace the antineutrino run of T2HK with antineutrinos from muon decay at rest (μ-DAR). This approach has the advantages of having higher statistics in both neutrino and antineutrino modes, and lower beam-on backgrounds for antineutrino run with reduced systematics. We find that a hybrid setup consisting of T2HK (ν) and μ-DAR \( \left(\overline{\nu}\right) \) in conjunction with full exposure from T2K and NOνA can resolve the issue of mass hierarchy at greater than 3σ C.L. irrespective of the choices of hierarchy, δ CP, and θ 23. This hybrid setup can also establish the CP-violation at 5σ C.L. for ∼ 55% choices of δ CP, whereas the same for conventional T2HK \( \left(\nu + \overline{\nu}\right) \) setup along with T2K and NOνA is around 30%. As far as the octant of θ 23 is concerned, this hybrid setup can exclude the wrong octant at 5σ C.L. if θ 23 is at least 3° away from maximal mixing for any δ CP.


Neutrino Physics CP violation 


Open Access

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Copyright information

© The Author(s) 2017

Authors and Affiliations

  • Sanjib Kumar Agarwalla
    • 1
    • 2
    Email author
  • Monojit Ghosh
    • 3
  • Sushant K. Raut
    • 4
    • 5
  1. 1.Institute of PhysicsBhubaneswarIndia
  2. 2.Homi Bhabha National Institute, Training School ComplexMumbaiIndia
  3. 3.Department of PhysicsTokyo Metropolitan UniversityHachiojiJapan
  4. 4.Department of Theoretical Physics, School of Engineering SciencesKTH Royal Institute of Technology, AlbaNova University CenterStockholmSweden
  5. 5.Center for Theoretical Physics of the Universe, Institute for Basic Science (IBS)DaejeonKorea

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