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Related papers: Reducing the hydrogen content in liquid helium

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Fundamental solid state physics phenomena typically occur at very low temperatures, requiring liquid helium cooling in experimental studies. Transmission electron microscopy is a well-established characterization method, which allows…

Instrumentation and Detectors · Physics 2019-10-02 Felix Börrnert , Felix Kern , Franziska Seifert , Thomas Riedel , Heiko Müller , Bernd Büchner , Axel Lubk

We review fundamental problems involved in liquid theory including both classical and quantum liquids. Understanding classical liquids involves exploring details of their microscopic dynamics and its consequences. Here, we apply the same…

Statistical Mechanics · Physics 2025-01-28 K. Trachenko

We present here a small-scale liquid Helium (LHe) immersion cryostat with an innovative optical setup suitable to work in long wavelength radiation ranges and under applied magnetic field. The cryostat is a multi stage device with several…

Instrumentation and Detectors · Physics 2020-07-09 S. J. Rezvani , D. Di Gioacchino , S. Tofani , A. Darco , C. Ligi , S. Lupi , C. Gatti , M. Cestelli Guidi , A. Marcelli

The compressibility of solid helium (3He and 4He) in the hcp and fcc phases has been studied by path-integral Monte Carlo. Simulations were carried out in both canonical (NVT) and isothermal-isobaric (NPT) ensembles at temperatures between…

Materials Science · Physics 2009-11-13 Carlos P. Herrero

We investigate the formation of molecular hydrogen (H_2) in a primordial H+He gas cloud irradiated by a power-law UV flux. We find that at high densities (>1 cm^{-3}) and low temperatures (<10^4 K), the background radiation enhances the…

Astrophysics · Physics 2009-10-28 Zoltan Haiman , Martin Rees , Abraham Loeb

Molecular hydrogen is a fascinating candidate for quantum fluid showing bosonic and fermionic superfluidity. We have studied diffusion dynamics of thin films of H$_2$, HD and D$_2$ adsorbed on a glass substrate by measurements of…

Strongly Correlated Electrons · Physics 2019-12-18 Takahiko Makiuchi , Katsuyuki Yamashita , Michihiro Tagai , Yusuke Nago , Keiya Shirahama

Behaviours of hydrogen, such as fluidity and metallicity, are crucial for our understanding of planetary interiors and the emerging field of high-temperature superconducting hydrides. These behaviours were discovered in complex phase…

A new search for a permanent electric dipole moment (EDM) of the neutron is underway using ultracold neutrons produced and held in a bath of superfluid helium. Attaining the target sensitivity requires maintaining an electric field of…

Instrumentation and Detectors · Physics 2007-05-23 J. C. Long , P. D. Barnes , J. G. Boissevain , D. J. Clark , M. D. Cooper , J. J. Gomez , S. K. Lamoreaux , R. E. Mischke , S. I. Penttila

The temperature of the low-density intergalactic medium is set by the balance between adiabatic cooling resulting from the expansion of the universe, and photo-heating by the UV-background. A sudden injection of entropy from the…

Astrophysics · Physics 2007-05-23 Tom Theuns , Saleem Zaroubi , Tae-Sun Kim

We study the interaction of atomic and molecular hydrogen with a surface of tholin, a man-made polymer considered to be an analogue of aerosol particles present in Titan's atmosphere, using thermal programmed desorption at low temperatures…

Earth and Planetary Astrophysics · Physics 2010-10-08 Ling Li , Hui Zhao , Gianfranco Vidali , Yechiel Frank , Ingo Lohmar , Hagai B. Perets , Ofer Biham

We report the application of evaporative cooling to clouds of trapped antiprotons, resulting in plasmas with measured temperature as low as 9~K. We have modeled the evaporation process for charged particles using appropriate rate equations.…

Low dimensional quantum fluids, where one can probe the effects of enhanced thermal and quantum fluctuations on macroscopic quantum wavefunctions, can be experimentally realized through transverse physical confinement of superfluid helium…

Mesoscale and Nanoscale Physics · Physics 2026-02-26 Sutirtha Paul , Taras Lakoba , Paul E. Sokol , Adrian Del Maestro

Alkali atoms do not stably embed in liquid helium-4 because the interatomic attractive potential is unable to overcome the short-range Pauli repulsion of the s electrons and the surface tension cost of the surrounding bubble. Similarly,…

Atomic and Molecular Clusters · Physics 2010-02-01 Casey Stark , Vitaly V. Kresin

The energy and angular momentum of both straight and curved vortex states of a helium nanodroplet are examined as a function of droplet size. For droplets in the size range of many experiments, it is found that during the pickup of heavy…

Condensed Matter · Physics 2007-05-23 Kevin K. Lehmann , Roman Schmied

We report on the low temperature behaviour of the colloidal electrolyte by means of Molecular Dynamics simulations, where the electrostatic interactions were modeled using effective screened interactions. As in previous works, we have found…

Soft Condensed Matter · Physics 2009-11-13 Jose B. Caballero , Antonio M. Puertas

Various mechanisms have been proposed for hydrogen embrittlement, but the causation of hydrogen-induced material degradation has remained unclear. This work shows hydrogen embrittlement due to phase instability (decomposition). In-situ…

Hydrodynamic outflows, such as those observed escaping close-in gas giant planets, are not isothermal in structure. Their highly ionized nature allows them to cool adiabatically at distances beyond several planetary radii. The contrast…

Earth and Planetary Astrophysics · Physics 2025-05-21 Matthäus Schulik , James Owen

The molecular phase of hydrogen converts to the atomic metallic phase at high pressures estimated usually as 300 - 500 GPa. We analyze the decay of metallic phase as the pressure is relieved below the transition one. The metallic state is…

Other Condensed Matter · Physics 2018-01-03 S. N. Burmistrov , L. B. Dubovskii

The influence of nitrogen impurities on the parameters of the self-sustained normal dc glow discharge at atmospheric pressure was studied. The concentrations of the low-excited helium atoms in states 2_1s, 2_1p, 2_3s and 2_3p were…

Plasma Physics · Physics 2007-05-23 Valery Arkhipenko , Andrey Kirillov , Leanid Simonchik , Siargey Zgirouski

Microwave heating of methane hydrate is investigated with electrostatic molecular dynamics simulations by the SPC/E water model. The structure I of methane hydrate is constructed. When the methane hydrate with a density of 0.91…

Chemical Physics · Physics 2023-11-27 Motohiko Tanaka , Motoyasu Sato , Shin Nakatani