It has been proposed that there could be a mirror copy of the standard model particles, restoring the parity symmetry in the weak interaction on the global level. Oscillations between a neutral ...standard model particle, such as the neutron, and its mirror counterpart could potentially answer various standing issues in physics today. Astrophysical studies and terrestrial experiments led by ultracold neutron storage measurements have investigated neutron to mirror-neutron oscillations and imposed constraints on the theoretical parameters. Recently, further analysis of these ultracold neutron storage experiments has yielded statistically significant anomalous signals that may be interpreted as neutron to mirror-neutron oscillations, assuming nonzero mirror magnetic fields. The neutron electric dipole moment collaboration performed a dedicated search at the Paul Scherrer Institute and found no evidence of neutron to mirror-neutron oscillations. Thereby, the following new lower limits on the oscillation time were obtained: τnn′>352 s at B′=0 (95% C.L.), τnn′>6s for 0.4μT<B′<25.7μT (95% C.L.), and τnn′/cosβ>9s for 5.0μT<B′<25.4μT (95% C.L.), where β is the fixed angle between the applied magnetic field and the local mirror magnetic field, which is assumed to be bound to the Earth. These new constraints are the best measured so far around B′∼10μT and B′∼20μT.
Abstract
The differential cross sections for the proton-deuteron breakup reaction have been measured for more than 200 angular configurations of outgoing protons in the range of polar angles from 13 ...to 27 degrees with a proton beam at 108 MeV. The paper presents the experimental results of the selected configurations, which are compared to state-of-the-art theoretical calculations. In some regions of the phase space, a strong influence of the Coulomb interaction is observed.
Differential cross section for the
1
H
(
d
,
p
p
)
n
reaction is sensitive to various dynamical ingredients and allows for thorough tests of theoretical potentials describing the interaction in the ...three nucleon systems. The analysis of the experimental data collected for the breakup reaction at the beam energy of 100 MeV has been performed and the first cross section results for selected configurations are presented in this paper. They are in good agreement with calculations based on the realistic potentials. Studies at this relatively low energy will also be important for examining awaited calculations within the Chiral Effective Field Theory.
Abstract
An experiment focused on studies of relativistic effects in the proton-deuteron breakup reaction has been performed at Cyclotron Center Bronowice in Kraków, Poland with the use of the Kratta ...detectors. Thirty Kratta modules have been arranged in a planar symmetric around beam axis configuration at few selected polar angles at which significant relativistic effects have been predicted. In front of each Kratta module 4 thin plastic scintillators were installed acting as a fast timing detectors to improve a trigger system. Determination of acceptance and efficiency of the detectors is discussed.
The differential cross sections for the
2
H(p,pp)n reaction have been measured for more than 80 angular configurations of the outgoing protons in the range of polar angles from 13
∘
to 33
∘
with ...a proton beam at 108 MeV. Data have been collected at the first experimental run in the Cyclotron Center Bronowice (CCB) at the Institute of Nuclear Physics PAS in Cracow, using the BINA detector setup. Analysis leading to determination of the breakup cross section values is described. Absolute normalization is obtained by normalization to the simultaneously measured
1
H(d,d)p scattering events. Experimental results are compared to the state-of-the-art theoretical calculations. Global analysis shows significant influence of the Coulomb interaction and small effects of three nucleon force in the studied phase space region.
Abstract
Applying a Mott polarimetry for measurement of the transverse polarization components of electrons from free neutron decay as well as proton momentum reconstruction using the combination of ...the time of flight method and the kinematical constrains of this three body decay, one gets access to eleven correlation coefficients of the neutron
β
-decay. Successful measurement of some of these coefficients would allow for an unique access to exotic scalar and tensor couplings of weak interactions and obtaining new constraints on their imaginary part, known with much worse accuracy. Results of the performance studies of some key experimental components of the prototype setup performed during the test run in 2021 at ILL PF1B neutron beam line are presented.
Analysis of the data acquired with the BINA detector system in
1
H(
d
,
pp
)
n
reaction at the beam energy of 80 MeV/nucleon makes a systematic analysis of the star configurations possible. This ...paper shows the preliminary cross section of the Forward-Plane Star (FPS) configuration with the neighbouring configurations.
We present a magnetometer based on optically pumped Cs atoms that measures the magnitude and direction of a 1 μT magnetic field. Multiple circularly polarized laser beams were used to probe the free ...spin precession of the Cs atoms. The design was optimized for long-time stability and achieves a scalar resolution better than 300 fT for integration times ranging from 80 ms to 1000 s. The best scalar resolution of less than 80 fT was reached with integration times of 1.6 to 6 s. We were able to measure the magnetic field direction with a resolution better than 10 μrad for integration times from 10 s up to 2000 s.
PDF
