Neutron Lifetime Puzzle

Session

Recent Advances in Neutron Lifetime Measurements

13 Sept 2025, 10:40

WHGA/001 - Auditorium (PSI)

Conveners

Recent Advances in Neutron Lifetime Measurements

• T. M. Ito (Los Alamos National Laboratory)

18. Current status and future activities of UCNtau+

Susan Seestrom (Los Alamos National Laboratory, Retired Senior Fellow and Guest Scientist)

13/09/2025, 10:40

invited

5. The NIST Beam Neutron Lifetime Experiments

Fred Wietfeldt (Tulane University)

13/09/2025, 11:10

invited

A series of neutron lifetime measurements using the beam method has been conducted at the National Institute of Standards and Technology (USA) for more than 30 years. In these experiments, a cold neutron beam passes through a quasi-Penning trap where protons from free neutron decay are captured and subsequently counted by a silicon detector. We will review the previous BL1 experiment (2005,...

3. A new results of neutron lifetime measurement with cold neutron beam at J-PARC

Kenji Mishima (RCNP, Osaka university)

13/09/2025, 11:55

invited

The ``neutron lifetime puzzle'' arises from the discrepancy between neutron lifetime measurements obtained using the beam method, which measures decay products, and the bottle method, which measures the disappearance of neutrons.
To resolve this puzzle, we conducted an experiment using a pulsed cold neutron beam at J-PARC. In this experiment, the neutron lifetime is determined from the ratio...