The formation and dynamics of topological defects of different structure has been of central interest in the study of the 3He superfluids. Compared to superfluid 4He-II, the variability of the important parameters with temperature and pressure is wider and many features are more ideal. This has made experimentally new approaches possible. An example is the formation of quantized vortices and ot...

We present a simple model of 3He and 4He transport in the mantle using the appropriate rates of mass and species transfer and 4He production. Previous workers have shown the presence of excess 3He in hotspots such as Hawaii and Iceland and inferred that these hotspots tap a source with a higher 3He/aHe ratio than the source region of mid-ocean ridge basalts (MORB). Hotspot ocean islands probabl...

A set of time integrated cosmogenic 3He production rates in olivines for the last 1.35 Ma are presented. We investigated three basaltic lava flow tops from Lanzarote, Canary Islands, Spain. The 40Ar/39Ar ages determined for those basalt flows by incremental laser heating of leached groundmass samples are 152 þ 26 ka, 281 þ 19 ka and 1.35 þ 0.01 Ma ( þ 2c). Three or four different olivine phenoc...

MR imaging with polarized noble gases has shown promise in both, biomedical and material’s imaging applications. Its advantage over the conventional proton MRI lies in its ability to produce high signal-to-noise ratio (SNR), high-resolution images at low magnetic field strengths. In this work: 1. We implemented and studied in detail two methods for detecting hyperpolarization levels of 129Xe an...

We describe the design and operation of an open-access, very-low-field, magnetic resonance imaging (MRI) system for in vivo hyperpolarized 3He imaging of the human lungs. This system permits the study of lung function in both horizontal and upright postures, a capability with important implications in pulmonary physiology and clinical medicine, including asthma and obesity. The imager uses a bi...

We present results of the Q−1 and period shift, P , for 3He confined in a 98% nominal open aerogel on a torsion pendulum. The aerogel is compressed uniaxially by 10% along a direction aligned to the torsion pendulum axis and was grown within a 400 μm tall pancake (after compression) similar to an Andronikashvili geometry. The result is a high Q pendulum able to resolve Q−1 and mass coupling of ...

Linear defects are generic in continuous media. In quantum systems they appear as topological line defects which are associated with a circulating persistent current. In relativistic quantum vacuum they are known as cosmic strings, in superconductors as quantized flux lines, and in superfluids and low-density atomic Bose-Einstein condensates as quantized vortex lines. We discuss unconventional ...

2014 Optical pumping of ground state 3He has several peculiar features because nuclear polarization is first obtained in the metastable 2 3S state and then transferred to the ground state (indirect optical pumping); this introduces non-linearities in the equation of evolution of the populations. Here we present a numerical calculation of the kinetics of optical pumping in 3He, which allows a de...