相关论文: BASE - The Baryon Antibaryon Symmetry Experiment
In this paper we study the possibility of testing Charge-Parity-Time Reversal (CPT) symmetry with cosmic microwave background (CMB) experiments. We consider two kinds of Chern-Simons (CS) term, electromagnetic CS term and gravitational CS…
Measurements of the double-differential charged pion production cross-section in the range of momentum 0.5 GeV/c < p < 8.0 GeV/c and angle 0.025 rad < theta <0.25 rad in collisions of protons on beryllium, carbon, nitrogen, oxygen,…
Nuclear spin-dependent parity violation arises from weak interactions between electrons and nucleons, and from nuclear anapole moments. We outline a method to measure such effects, using a Stark-interference technique to determine the…
According to the CPT theorem, which states that the combined operation of charge conjugation, parity transformation and time reversal must be conserved, particles and their antiparticles should have the same mass and lifetime but opposite…
The COMPASS Experiment at the CERN SPS has a broad physics program focused on the nucleon spin structure and on hadron spectroscopy, using muon and hadron beams. Main objectives for the spin program with the muon beam are the direct…
The experimental concept of a search for a long-range coupling between rubidium (Rb) nuclear spins and the mass of the Earth is described. The experiment is based on simultaneous measurement of the spin precession frequencies for…
Low energy antiprotons offer excellent opportunities to study properties of fundamental forces and symmetries in nature. Experiments with them can contribute substantially to deepen our fundamental knowledge in atomic, nuclear and particle…
The General AntiParticle Spectrometer (GAPS) is a balloon-borne instrument designed to detect cosmic-ray antimatter using the novel exotic atom technique, obviating the strong magnetic fields required by experiments like AMS, PAMELA, or…
Random motion of spins is usually detrimental in magnetic resonance experiments. The spin diffusion in non-uniform magnetic fields causes broadening of the resonance and limits the sensitivity and the spectral resolution in applications…
Atomic microwave clocks based on hyperfine transitions, such as the caesium standard, tick with a frequency that is proportional to the magnetic moment of the nucleus. This magnetic moment varies strongly between isotopes of the same atom,…
The MuCap experiment measures the singlet rate Lambda_S of muon capture on the proton. A negative muon beam is stopped in a time projection chamber filled with ultra-pure hydrogen gas at 10 bar and room temperature. In combination with the…
The fields of particle and nuclear physics have undertaken extensive programs to search for evidence of physics beyond that explained by current theories. The observation of the Higgs boson at the Large Hadron Collider completed the set of…
The precise knowledge of the atomic masses of light atomic nuclei, e.g. the proton, deuteron, triton and helion, is of great importance for several fundamental tests in physics. However, the latest high-precision measurements of these…
Upon a suggestion of Kostelecky et al., we have performed a test of CPT and Lorentz invariance from the microwave spectroscopy of muonium. New terms in their standard model extension violating CPT and Lorentz symmetry would appear as…
This paper describes a time-marking system that enables a measurement of the in-plane (horizontal) polarization of a 0.97-GeV/c deuteron beam circulating in the Cooler Synchrotron (COSY) at the Forschungszentrum J\"ulich. The clock time of…
This thesis discusses two different approaches for the measurement of cosmic-ray antiparticles in the GeV to TeV energy range. The first part of this thesis discusses the prospects of antiparticle flux measurements with the proposed PEBS…
DAE\delta ALUS, the Decay At-rest Experiment for \delta_{CP} at a Laboratory for Underground Science will look for evidence of CP-violation in the neutrino sector, an ingredient in theories that seek to explain the matter/antimatter…
The asymmetry parameter P was measured for the elastic pion-proton scattering in the very backward angular region of theta_cm ~ 150-170^o at several pion beam energies in the invariant mass range containing most of the pion-proton…
From recent charge exchange measurements in the extreme forward direction, an independent and precise determination of the pion nucleon coupling constant is possible. This determination has reopened the debate on the value of this…
The flavor-separated polarized parton distribution functions for light quarks and anti-quarks in the proton can be studied in the production of $W$ bosons in $p$+$p$ collisions. The $W$s are produced in processes like $u+\bar{d}\rightarrow…