helium-4

Information about helium-4

Helium-4 is a non-radioactive and light isotope of helium. It is by far the most abundant of the two naturally-occurring isotopes of helium, making up about 99.99986% of the helium on earth. Its nucleus is a boson and an alpha particle, having two protons and two neutrons. Alpha decay is a common decay mode for many radioactive isotopes. In fact, alpha decay of heavy elements is the source of most naturally occurring helium-4 on earth. Helium-4 is also a byproduct of nuclear fusion in stars.

When helium-4 is cooled to below 2.17 kelvins (–271 °C), it becomes a superfluid, with properties that are very unlike those of an ordinary liquid. For example, if helium-4 is kept in an open vessel, a thin film will climb up the sides of the vessel and overflow. Another name for this property of Helium is Rollin film. This strange behaviour is a result of the Clausius-Clapeyron relation and cannot be explained by the current model of classical mechanics nor by nuclear or electrical models; it is only understood as a quantum mechanical phenomenon.

Helium-3Isotopes of HeliumHelium-5
Produced from:
Lithium-5 (p)
Helium-5 (n)
Beryllium-6 (2p)'''		Decay chainDecays to:
Stable
Radioactive decay is the process in which an unstable atomic nucleus loses energy by emitting radiation in the form of particles or electromagnetic waves. This decay, or loss of energy, results in an atom of one type, called the parent nuclide
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Isotopes are any of the several different forms of an element each having different atomic mass (mass number). Isotopes of an element have nuclei with the same number of protons (the same atomic number) but different numbers of neutrons.
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Helium (He) is a colorless, odorless, tasteless, non-toxic, inert monatomic chemical element that heads the noble gas series in the periodic table and whose atomic number is 2.
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In particle physics, bosons are force carrier particles, such as the photon. They may be either elementary or composite. They are distinguished from fermions (matter particles) by their integer spin. Bosons are named after Indian physicist Satyendra Nath Bose.
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Alpha particles (named after and denoted by the first letter in the Greek alphabet, α) consist of two protons and two neutrons bound together into a particle identical to a helium nucleus; hence, it can be written as He2+ or 42He.
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Proton

The quark structure of the proton.
Composition: 2 up, 1 down
Family: Fermion
Group: Quark
Interaction: Gravity, Electromagnetic, Weak, Strong
Antiparticle: Antiproton
Discovered: Ernest Rutherford (1919)
Symbol: p+
Mass: 1.
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Neutron

The quark structure of the neutron.
Composition: one up, two down
Family: Fermion
Group: Quark
Interaction: Gravity, Electromagnetic, Weak, Strong
Antiparticle: Antineutron
Discovered: James Chadwick[1]
Symbol: n
Mass: 1.
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Alpha decay is a type of radioactive decay in which an atomic nucleus emits an alpha particle (two protons and two neutrons bound together into a particle identical to a helium nucleus) and transforms (or 'decays') into an atom with a mass number 4 less and atomic number 2 less.
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A radionuclide is an atom with an unstable nucleus, which is a nucleus characterized by excess energy which is available to be imparted either to a newly-created radiation particle within the nucleus, or else to an atomic electron (see internal conversion) .
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nuclear fusion is the process by which multiple atomic particles join together to form a heavier nucleus. It is accompanied by the release or absorption of energy. Iron and nickel nuclei have the largest binding energies per nucleon of all nuclei and therefore are the most stable.
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STAR is an acronym for:

Organizations:
  • Society for Telescopy, Astronomy, and Radio, a non-profit astronomy club in New Jersey
  • Special Tasks and Rescue or Special Tactics and Response, synonyms for SWAT

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The kelvin (symbol: K) is a unit increment of temperature and is one of the seven SI base units. The Kelvin scale is a thermodynamic (absolute) temperature scale where absolute zero — the coldest possible temperature — is zero kelvins
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Superfluidity is a phase of matter or description of heat capacity in which "unusual" effects are observed when liquids, typically of helium-4 or helium-3, overcome friction by surface interaction when at a stage, known as the "lambda point" for helium-4, at which the liquid's
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Rollin film also covers the interior of the larger container; if it were not sealed, the helium II would creep out and escape.]]

A Rollin film, named after Bernard V. Rollin, is a 30 nm-thick liquid film of helium in the helium II state.
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The Clausius-Clapeyron relation, named after Rudolf Clausius and Émile Clapeyron, is a way of characterizing the phase transition between two states of matter, such as solid and liquid.
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model is used in various contexts to mean a physical representation of some thing. That thing may be a single item or object (for example, a bolt) or a large system (for example, the Solar System).
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Classical mechanics (commonly confused with Newtonian mechanics, which is a subfield thereof) is used for describing the motion of macroscopic objects, from projectiles to parts of machinery, as well as astronomical objects, such as spacecraft, planets, stars, and galaxies.
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Nuclear physics is the branch of physics concerned with the nucleus of the atom. It has three main aspects: probing the fundamental particles (protons and neutrons) and their interactions, classifying and interpreting the properties of nuclei, and providing technological advances.
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Electricity (from New Latin ēlectricus, "amberlike") is a general term for a variety of phenomena resulting from the presence and flow of electric charge. This includes many well-known physical phenomena such as lightning, electromagnetic fields and electric currents,
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quantum mechanics is the study of the relationship between energy quanta (radiation) and matter, in particular that between valence shell electrons and photons. Quantum mechanics is a fundamental branch of physics with wide applications in both experimental and theoretical physics.
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Helium-3 (He-3) is a light, non-radioactive isotope of helium with two protons and one neutron, which is rare on Earth; it is sought after for use in nuclear fusion research.
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Helium (He)
Standard atomic mass: 4.002602(2) u

Natural helium isotopes

For more details on this topic, see Helium-3.

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Helium (He) is a colorless, odorless, tasteless, non-toxic, inert monatomic chemical element that heads the noble gas series in the periodic table and whose atomic number is 2.
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Helium (He)
Standard atomic mass: 4.002602(2) u

Natural helium isotopes

For more details on this topic, see Helium-3.

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Proton emission (also known as proton radioactivity) is a type of radioactive decay in which a proton is ejected from a nucleus. Proton emission can occur from high-lying excited states in a nucleus following a beta decay, in which case the process is known as beta-delayed proton
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Helium (He)
Standard atomic mass: 4.002602(2) u

Natural helium isotopes

For more details on this topic, see Helium-3.

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Neutron emission is a type of radioactive decay in which an atom contains excess neutrons and a neutron is simply ejected from the nucleus. Two examples of isotopes which emit neutrons are helium-5 and beryllium-13.
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In nuclear science, the decay chain refers to the radioactive decay of different discrete radioactive decay products as a chained series of transformations. Most radioactive elements do not decay directly to a stable state, but rather undergo a series of decays until eventually a
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