A laser-induced fluorescence (LIF) spectroscopy has been applied to an electron cyclotron resonance plasma. The absolute azimuthal flow velocity has been determined by the Doppler-shifted LIF spectrum and compared with that measured with a directional Langmuir probe (DLP) and the E × B drift velocity, respectively. The velocity profiles obtained with the three different methods show good agreement. The validity of LIF spectroscopy as a tool of local and absolute flow velocity measurement has been confirmed.

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The physics impact of hydrogen antihydrogen spectroscopy on fundamental-physics research is outlined. Particular emphasis is given to the motivations and ideas behind CPT and Lorentz tests. Matter-antimatter interactions are discussed by elaborating on hydrogen-antihydrogen collisions leading to various processes. Also discussed is the simulation of antiproton interactions with the positron plasma for antihydrogen formation.

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Antiprotons produced by a proton synchrotron are decelerated and cooled first to 5.3 MeV by stochastic cooling and electron cooling in the Antiproton Decelerator (AD) ring, then to 111 keV by a Radio Frequency Quadrupole Decelerator (RFQD). After the deceleration of the RFQD, antiprotons are degraded by thin PET foils and injected into the Multi-Ring electrode Trap(MRT). Electrons are preloaded in the MRT to cool the antiprotons to subelectron volt energy region. Ramping up the trapping potential slowly allows ultra-slow antiprotons of 10-500eV to be extracted from the strong magnetic field region. Positrons from ²²Na are cooled by N₂ gas or by electrons to form a cold positron plasma. A rotating electric field is used to radially compress the plasma.

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Diagnostics of antiproton beams and nonneutral plasmas are described in this chapter. Parallel plate secondary electron emission detectors are used to non-destructively observe the beam position and intensity without loss. Plastic scintillation tracking detectors are useful in determining the position of annihilations of antiprotons in the trap. Three-dimensional imaging of antiprotons in a Penning trap is discussed. The unique capability of antimatter particle imaging has allowed the observation of the spatial distribution of particle loss in a trap. Radial loss is localized to small spots, strongly breaking the azimuthal symmetry expected for an ideal trap. By observing electrostatic eigen-modes of nonneutral plasmas trapped in the Multi-ring electrode trap, the non-destructive measurement of plasma parameters is performed.

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The ATHENA experiment at CERN produced and detected the first cold antihydrogen atoms. Antiprotons and positrons are mixed in a double Penning trap, known as a nested trap. The production of antihydrogen atoms was identified by detecting their annihilations signatures at trap wall. With the ATHENA results subsequently confirmed by another CERN experiment, ATRAP, cold antihydrogen research is entering an exciting era.

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Conditions required for magnetic confinement of antihydrogen atoms are briefly described. Then, several ideas of antihydrogen confinement in minimum-B fields are introduced with some comments. Two methods for extracting antihydroten atoms from their synthesized region are also described. Paul trap with a superconducting wall cavity has the potential to trap antihydrogen atoms in a space with no steady magnetic field.

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Escaping energetic ion diagnostics in magnetically confined plasma experiments are described in this lecture note. Experimental results from escaping energetic ion diagnostics in TFTR, JFT-2M, CHS and W7-AS are shown. In addition to mechanism of energetic ion loss from a viewpoint of particle orbit, effect of MHD activity on energetic particle transport is reviewed.

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