Results 21 to 30 of about 676,534 (379)
Helium in the Atmosphere [PDF]
Nature, 1898 THE discovery of helium lines in the spectrum of neon, by Mr. E. C. C. Baly, will necessitate a modification of the views we have expressed in our communication to the British Association at Bristol. We there estimated the density of neon at 9.6, allowing for the presence of a certain proportion of argon unavoidably left in the neon.
Ramsay, William, Travers, Morris W.
+10 more sources
The European Physical Journal D, 2013 Using a configuration-interaction variational method, we accurately compute the reduced, single-electron von Neumann entropy for several low-energy, singlet and triplet eigenstates of helium atom. We estimate the amount of electron-electron orbital entanglement for such eigenstates and show that it decays with energy.
Giuliano Benenti +3 more
openaire +5 more sources
Spectrally resolved helium absorption from the extended atmosphere of a warm Neptune-mass exoplanet [PDF]
Science, 2018 Helium escaping from hot gas giants Many gas giant exoplanets orbit so close to their host star that they are heated to high temperatures, causing atmospheric gases to escape.
R. Allart +12 more
semanticscholar +1 more source
High-resolution confirmation of an extended helium atmosphere around WASP-107b [PDF]
Astronomy & Astrophysics, 2019 Context. Probing the evaporation of exoplanet atmospheres is key to understanding the formation and evolution of exoplanetary systems. The main tracer of evaporation in the UV is the Lyman-α transition, which can reveal extended exospheres of neutral ...
R. Allart +9 more
semanticscholar +1 more source
Frontiers in Earth Science, 2022 Carbon dioxide (CO2) is released from the Earth’s interior into the atmosphere through both volcanic and non-volcanic sources in a variety of tectonic settings.
Paolo Randazzo +10 more
doaj +1 more source
The ionization of helium by neutral helium atoms [PDF]
Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences, 1946 A method is described for investigating the ionization produced in helium by collisions between quasi-stationary atoms—that is, atoms possessing only therm al velocities—and a beam of neutral helium atoms with kinetic energy less than 100 eV. Ionization is shown to begin when the kinetic energy of the bombarding atoms is twice as great as the minimum ...
Frank Horton, Dorothy M. Millest
openaire +3 more sources
Metals, 2021 Electron beam melting (EBM) is a metal powder bed fusion additive manufacturing (AM) technology that facilitates the production of metal parts by selectively melting areas in layers of metal powder.
Elroei Damri +5 more
doaj +1 more source
Helium Emissions Observed in Ground-Based Spectra of Solar Prominences [PDF]
, 2012 The only prominent line of singly ionized helium in the visible spectral range, helium-II 4686 A, is observed together with the helium-I 5015 A singlet and the helium-I 4471 A triplet line in solar prominences.
Bianda, Michele +3 more
core +2 more sources
Cavitation pressure in liquid helium [PDF]
, 2001 Recent experiments have suggested that, at low enough temperature, the homogeneous nucleation of bubbles occurs in liquid helium near the calculated spinodal limit. This was done in pure superfluid helium 4 and in pure normal liquid helium 3. However, in
B. M. Abraham +31 more
core +3 more sources
Rb*He_n exciplexes in solid 4_He [PDF]
, 2006 We report the observation of emission spectra from Rb*He_n exciplexes in solid 4He. Two different excitation channels were experimentally identified, viz., exciplex formation via laser excitation to the atomic 5P3/2 and to the 5P1/2 levels.
Hofer, A. +4 more
core +2 more sources