Wave, antenna impedance, plasma density, and temperature anisotropy measurements are carried out for a helicon plasma source in nonuniform and uniform static magnetic fields. Strong axial density gradients associated with the nonuniform magnetic fields are observed to affect wave fields, absorption, and source efficiency. The wave field and antenna input impedance measurements are compared with...

introduction range and diffusion of positron-emitting radiopharmaceuticals are important parameters for image resolution in positron emission tomography (pet). in this study, geant4 toolkit was applied to study positron diffusion in soft tissues with and without a magnetic field for six commonly used isotopes in pet imaging including 11c, 13n, 15o, 18f, 68ga, and 82rb. materials and methods gea...

A near-IR line of Mn I as a diagnostic tool of the average magnetic energy in the solar photosphere ABSTRACT We report on spectropolarimetric observations of a near-IR line of Mn I located at 15262.702Å whose intensity and polarization profiles are very sensitive to the presence of hyperfine structure. A theoretical investigation of the magnetic sensitivity of this line to the magnetic field un...

Abstract We investigated the diagnostic potential of Stokes V profile H α line to probe chromospheric line-of-sight (LOS) magnetic field ( B LOS ) by comparing inferred from weak approximation (WFA) with that multiline inversions Ca ii 8542 Å, Si i 8536 and Fe 8538 Å lines using STiC inversion code. Simultaneous spectropolarimetric observations a pore in spectral obtained SPINOR at Dunn Solar T...

A large diameter (up to 73.8 cm), high-density helicon plasma with short axial length (≤ 81 cm) has been successfully produced using a flat spiral antenna. The electron plasma density can reach up to ∼ 10 cm−3 with the input radio frequency (rf) power of < 4 kW for various axial lengths, and the density scaling as a function of the axial length is in good agreement with expectations. The strong...

Plasma confined by a magnetic dipole is stabilized, at low beta, by magnetic compressibility. The ideal magnetohydrodynamic (MHD) requirements for stability against interchange and high-n ballooning modes are derived at arbitrary beta for a fusion grade laboratory plasma confined by a levitated dipole. A high beta MHD equilibrium is found numerically with a pressure profile near marginal stabil...

We present a general radiative transfer model which allows appropriate Zeeman diagnostics of small scale and unresolved solar magnetic fields. Present modeling techniques still rely to a large extent on a-priori assumptions about the geometry of the underlying magnetic field. In an effort to obtain a more flexible and unbiased approach we pursue a rigorous statistical description of the underly...