Issues

 / 

2019

 / 

June

  

Physics of our days


Disagreement between measurements of the neutron lifetime by the ultracold neutron storage method and the beam technique


The National Research Center "Kurchatov Institute", Konstantinov Petersburg Nuclear Physics Institute, Orlova Roshcha, Gatchina, Leningradskaya Region, 188300, Russian Federation

Recent measurements of neutron lifetime performed using a gravitational trap of ultracold neutrons (UCNs) (Konstantinov Petersburg Nuclear Physics Institute, Russia) and a magnetic UCN trap (LANL, USA) have confirmed PNPI's result of 2005. The results of the experiments with stored UCNs agree with each other but differ from those of the beam experiment (NIST, USA) by 3.5$\sigma$ (corresponding to 1% in the decay probability). This disagreement is currently discussed in the literature as a 'neutron anomaly'. We analyze possible reasons for that disagreement and test the experimental data for the neutron lifetime and beta-decay asymmetry within the Standard model. The test is only passed for the neutron lifetime values that are obtained using the UCN storage method.

Fulltext pdf (595 KB)
Fulltext is also available at DOI: 10.3367/UFNe.2018.11.038475
Keywords: neutron lifetime, particle physics, dark matter
PACS: 06.20.−f, 12.60.−i, 14.20.Dh (all)
DOI: 10.3367/UFNe.2018.11.038475
URL: https://ufn.ru/en/articles/2019/6/c/
000484015200003
2-s2.0-85072924865
2019PhyU...62..596S
Citation: Serebrov A P "Disagreement between measurements of the neutron lifetime by the ultracold neutron storage method and the beam technique" Phys. Usp. 62 596–601 (2019)
BibTexBibNote ® (generic)BibNote ® (RIS)MedlineRefWorks

Received: 13th, April 2018, revised: 2nd, November 2018, 15th, November 2018

Оригинал: Серебров А П «Разногласие между методом хранения ультрахолодных нейтронов и пучковым методом при измерении времени жизни нейтрона» УФН 189 635–641 (2019); DOI: 10.3367/UFNr.2018.11.038475

References (46) Cited by (11) Similar articles (17) ↓

  1. Yu.A. Mostovoi, K.N. Mukhin, O.O. Patarakin “The neutron yesterday, today, and tomorrowPhys. Usp. 39 925–958 (1996)
  2. M.I. Vysotsky, E.V. Zhemchugov “Equivalent photons in proton and ion—ion collisions at the LHCPhys. Usp. 62 910–919 (2019)
  3. I.M. Dremin “The interaction region of high energy protonsPhys. Usp. 58 61–70 (2015)
  4. V.V. Anisovich “Universality of hadron cross section at ultrahigh energiesPhys. Usp. 58 963–967 (2015)
  5. D.I. Kazakov “Prospects of elementary particle physicsPhys. Usp. 62 364–377 (2019)
  6. B. Heinemann, Y. Nir “The Higgs program and open questions in particle physics and cosmologyPhys. Usp. 62 920–930 (2019)
  7. V.A. Rubakov “Large Hadron Collider’s discovery of a new particle with Higgs boson propertiesPhys. Usp. 55 949–957 (2012)
  8. L.B. Okun “Particle physics prospects: August 1981Phys. Usp. 55 958–962 (2012)
  9. L.B. Okun “Epilogue to the discovery of a particle similar to the Higgs boson: August 2012Phys. Usp. 55 963–964 (2012)
  10. S.V. Troitsky “Unsolved problems in particle physicsPhys. Usp. 55 72–95 (2012)
  11. A. Bettini “Physics beyond the Standard Model: experiments at the Gran Sasso LaboratoryPhys. Usp. 44 931–954 (2001)
  12. A.V. Semenov “Observation of very-large-Q2 anomalous events in ep collisions on the HERA colliderPhys. Usp. 40 739–740 (1997)
  13. I.B. Khriplovich “The discovery of the nuclear anapole momentPhys. Usp. 40 1161–1162 (1997)
  14. V.I. Dokuchaev, Yu.N. Eroshenko “Physical laboratory at the center of the GalaxyPhys. Usp. 58 772–784 (2015)
  15. E.A. Khazanov, S.Yu. Mironov, G. Mourou “Nonlinear compression of high-power laser pulses: compression after compressor approachPhys. Usp. 62 1096–1124 (2019)
  16. S.M. Stishov, A.E. Petrova “Helical itinerant magnet MnSi: magnetic phase transitionPhys. Usp. 60 1268–1276 (2017)
  17. V.B. Braginskii “Gravitational-wave astronomy: new methods of measurementsPhys. Usp. 43 691–699 (2000)

The list is formed automatically.

© 1918–2024 Uspekhi Fizicheskikh Nauk
Email: ufn@ufn.ru Editorial office contacts About the journal Terms and conditions