papers

Publications (19)

nucl-ex2006

Upper Bounds on Parity Violating Gamma-Ray Asymmetries in Compound Nuclei from Polarized Cold Neutron Capture

M. T. Gericke, J. D. Bowman, R. D. Carlini +33

Parity-odd asymmetries in the electromagnetic decays of compound nuclei can sometimes be amplified above values expected from simple dimensional estimates by the complexity of comp…

nucl-ex2022

Absolute He polarimetry for a double-chambered cell using transmission of thermal neutrons

A. Watanabe, K. Sekiguchi, T. Ino +5

We present an absolute He polarimetry method based on thermal neutron transmission for a double-chambered cell. This method utilizes the fact that a He nucleus has a large…

nucl-ex2004

A Current Mode Detector Array for Gamma-Ray Asymmetry Measurements

M. T. Gericke, C. Blessinger, J. D. Bowman +15

We have built a CsI(Tl) gamma-ray detector array for the NPDGamma experiment to search for a small parity-violating directional asymmetry in the angular distribution of 2.2 MeV gam…

physics.ins-det2015

Pulsed UCN production using a Doppler shifter at J-PARC

S. Imajo, K. Mishima, M. Kitaguchi +8

We have constructed a Doppler-shifter-type pulsed ultra-cold neutron (UCN) source at the Materials and Life Science Experiment Facility (MLF) of the Japan Proton Accelerator Resear…

nucl-ex2023

Spin dependence in the -wave resonance of

T. Okudaira, R. Nakabe, S. Endo +24

We measured the spin dependence in a neutron-induced -wave resonance by using a polarized epithermal neutron beam and a polarized nuclear target. Our study focuses on the 0.75~e…

physics.ins-det2024

Performance of the Fully-equipped Spin Flip Chopper For Neutron Lifetime Experiment at J-PARC

K. Mishima, G. Ichikawa, Y. Fuwa +19

To solve the ''neutron lifetime puzzle,'' where measured neutron lifetimes differ depending on the measurement methods, an experiment with pulsed neutron beam at J-PARC is in progr…

hep-ex2020

Neutron lifetime measurement with pulsed cold neutrons

K. Hirota, G. Ichikawa, S. Ieki +26

The neutron lifetime has been measured by comparing the decay rate with the reaction rate of He nuclei of a pulsed neutron beam from the spallation neutron source at the Japan…

nucl-ex2024

Improved measurements of neutron lifetime with cold neutron beam at J-PARC

Y. Fuwa, T. Hasegawa, K. Hirota +28

The ``neutron lifetime puzzle'' arises from the discrepancy between neutron lifetime measurements obtained using the beam method, which measures decay products, and the bottle meth…

nucl-ex2020

Transverse asymmetry of rays from neutron-induced compound states of

T. Yamamoto, T. Okudaira, S. Endo +17

A correlation term in the reaction has been studied utilizing epithermal polarized neutrons and germanium…

nucl-ex2019

Improved determination of thermal cross section of 14N(n,p)14C for the neutron lifetime measurement

R. Kitahara, K. Hirota, S. Ieki +21

In a neutron lifetime measurement at the Japan Proton Accelerator Complex, the neutron lifetime is calculated by the neutron decay rate and the incident neutron flux. The flux is o…

physics.atom-ph2018

Development of co-located Xe and Xe nuclear spin masers with external feedback scheme

T. Sato, Y. Ichikawa, S. Kojima +23

We report on the operation of co-located Xe and Xe nuclear spin masers with an external feedback scheme, and discuss the use of Xe as a comagnetometer…

hep-ex2021

Precise Neutron Lifetime Measurement Using Pulsed Neutron Beams at J-PARC

N. Sumi, K. Hirota, G. Ichikawa +18

A neutron decays into a proton, an electron, and an anti-neutrino through the beta-decay process. The decay lifetime (880 s) is an important parameter in the weak interaction…

physics.ins-det2015

Development of time projection chamber for precise neutron lifetime measurement using pulsed cold neutron beams

Y. Arimoto, N. Higashi, Y. Igarashi +24

A new time projection chamber (TPC) was developed for neutron lifetime measurement using a pulsed cold neutron spallation source at the Japan Proton Accelerator Research Complex (J…

nucl-ex2024

Transverse asymmetry of individual -rays in the La(, )La reaction

M. Okuizumi, C. J. Auton, S. Endo +21

The enhancement of the parity-violating asymmetry in the vicinity of -wave compound nuclear resonances was observed for a variety of medium-heavy nuclei. The enhanced parity-vio…

nucl-ex2019

Measurement of 3He analyzing power for p-3He scattering using the polarized 3He target

A. Watanabe, S. Nakai, K. Sekiguchi +34

Proton-3He scattering is one of the good probes to study the T=3/2 channel of three--nucleon forces. We have measured 3He analyzing powers for p-3He elastic scattering with the pol…

physics.ins-det2020

Development and application of a He Neutron Spin Filter at J-PARC

T. Okudaira, T. Oku, T. Ino +22

We are developing a neutron polarizer with polarized He gas, referred to as a He spin filter, based on the Spin Exchange Optical Pumping (SEOP) for polarized neutron scatte…

nucl-ex2021

Proton- elastic scattering at intermediate energies

A. Watanabe, S. Nakai, Y. Wada +42

We present a precise measurement of the cross section, proton and analyzing powers, and spin correlation coefficient for - elastic scattering near…

physics.ins-det2024

Circular polarization measurement for individual gamma rays in capture reactions with intense pulsed neutrons

S. Endo, R. Abe, H. Fujioka +21

Measurements of circular polarization of -ray emitted from neutron capture reactions provide valuable information for nuclear physics studies. The spin and parity of excited st…

nucl-ex2023

High sensitivity of a future search for P-odd/T-odd interactions on the 0.75 eV -wave resonance in forward transmission determined using pulsed neutron beam

R. Nakabe, C. J. Auton, S. Endo +27

Neutron transmission experiments can offer a new type of highly sensitive search for time-reversal invariance violating (TRIV) effects in nucleon-nucleon interactions via the same…