Helium-4 (4 He ) is a stable isotope of the element helium. It is by far the more abundant of the two naturally occurring isotopes of helium, making up...

nuclear binding energy (per nucleon) of helium-4, with respect to the next three elements after helium. This helium-4 binding energy also accounts for why...

Superfluid helium-4 (helium II or He-II) is the superfluid form of helium-4, an isotope of the element helium. A superfluid is a state of matter in which...

there are nine known isotopes of helium (2He) (standard atomic weight: 4.002602(2)), only helium-3 (3 He ) and helium-4 (4 He ) are stable. All radioisotopes...

Liquid helium is a physical state of helium at very low temperatures at standard atmospheric pressures. Liquid helium may show superfluidity. At standard...

Helium-3 (3He see also helion) is a light, stable isotope of helium with two protons and one neutron. (In contrast, the most common isotope, helium-4...

protons and two neutrons bound together into a particle identical to a helium-4 nucleus. They are generally produced in the process of alpha decay but...

universe's helium (as isotope helium-4 (4He)), along with small fractions of the hydrogen isotope deuterium (2H or D), the helium isotope helium-3 (3He)...

nuclear fusion reactions by which three helium-4 nuclei (alpha particles) are transformed into carbon. Helium accumulates in the cores of stars as a result...

include the photon and atoms with an even number of neutrons (such as helium-4 (4 He )), are allowed to share a quantum state. Einstein proposed that cooling...

cooling of helium-4 (the more common isotope of helium), a 1-K pot liquefies a small amount of helium-3 in a small vessel called a helium-3 pot. Evaporative...

characteristic manner described by Bose–Einstein statistics: for example a gas of helium-4 atoms becomes a superfluid at temperatures close to absolute zero. Similarly...

Once the helium-3 has been produced, there are four possible paths to generate 4 He . In p–p I, helium-4 is produced by fusing two helium-3 nuclei; the...

nuclear fission. Nuclear fusion uses lighter elements, such as hydrogen and helium, which are in general more fusible; while the heavier elements, such as...

averages. For example, an atom of helium-4 has a mass of 4.0026 Da. This is an intrinsic property of the isotope and all helium-4 atoms have the same mass. Acetylsalicylic...

composite and wide spectral lines and helium with the inherently wide spectral line. Magnetometers based on helium-4 excited to its metastable triplet state...

rotate indefinitely. Superfluidity occurs in two isotopes of helium (helium-3 and helium-4) when they are liquefied by cooling to cryogenic temperatures...

region. The cooling power is provided by the heat of mixing of the helium-3 and helium-4 isotopes. The dilution refrigerator was first proposed by Heinz...

involve more than one solid phase, for substances with multiple polymorphs. Helium-4 is unusual in that it has no sublimation/deposition curve and therefore...

The helium hydride ion, hydridohelium(1+) ion, or helonium is a cation (positively charged ion) with chemical formula HeH+. It consists of a helium atom...

helium Helium-3 Helium-4 Helium (band), American rock band Helium (Pram album), 1994 Helium (H3llb3nt album), 1998 Helium (Homeshake album) "Helium" (Sia...

number 4; it is therefore also helium-4. The complete equation therefore reads: 6 3Li  + 2 1H  → 4 2He  + 4 2He . or more simply: 6 3Li  + 2 1H  → 2 4 2He...

Stellar nucleosynthesis has occurred since the original creation of hydrogen, helium and lithium during the Big Bang. As a predictive theory, it yields accurate...

California Radiation Laboratory) by bombarding curium with alpha particles (helium-4 ions). It is an actinide element, the sixth transuranium element to be...

heavier elements, initially deuterium which itself quickly fuses into mainly helium-4. By 20 minutes, the universe is no longer hot enough for nuclear fusion...

A helium atom is an atom of the chemical element helium. Helium is composed of two electrons bound by the electromagnetic force to a nucleus containing...

Helium is the smallest and the lightest noble gas and one of the most unreactive elements, so it was commonly considered that helium compounds cannot exist...

H.; et al. (STAR Collaboration) (2011). "Observation of the antimatter helium-4 nucleus". Nature. 473 (7347): 353–356. arXiv:1103.3312. Bibcode:2011Natur...

the helium-3 isotope, consisting of two protons and one neutron. The nucleus of the other (and far more common) stable isotope of helium, helium-4, consisting...

The helium dimer is a van der Waals molecule with formula He2 consisting of two helium atoms. This chemical is the largest diatomic molecule—a molecule...