Subject |
is part of |
has acceptance statu |
is an instance of |
has antiparticle |
has number of quark |
has decompostion temperature |
has symbol |
has domain |
carries the force |
has lifetime |
has propagation direction |
has period |
has decay product |
has amplitude |
has discovery in space date |
has composition |
is a kind of |
has mass |
has quantum behavior |
has spin |
has synonym |
has definition |
has desintegration energy |
ammonia | | | neutral particle | | | | NH3 | | | | | | | | | | | | | | | | |
antineutrino | | | | neutrino | | | | | | | | | | | | | antiparticle | | Fermi-Dirac statistics | 1/2 | | The antiparticle of a neutrino. | |
antineutron | | | radioactive particle | neutron | 3 | | | | | The average time in which a particle decays | | | the products produced immediately after decay | | | | | | Fermi-Dirac statistics | 1/2 or 3/2 | | The antiparticle of a neutron. A neutron and antineutron both have the same mass and zero electric charge, but can be differentiated by their interactions: a neutron and an antineutron can annihilate into gamma rays, while two neutrons cannot. | the total energy produced when the particle decays |
carbon monoxide | | | neutral particle | | | < 10000 K | CO | | | | | | | | | | | | | | | A molecule consisting of one carbon atom and one oxygen atom. It is the most abundant interstellar molecule after molecular hydrogen and is especially useful because it radiates at radio wavelengths, so astronomers can use it to map the distribution of molecular hydrogen. | |
graviton | | hypothetical | | | | | | | gravity | | | | | | | | hypothetical particle | 0 | Bose-Einstein statistics | 2 | force carrier | The quanta thought to convey gravitational force; analogous to the photons, gluons, and intermediate vector bosons of electromagnetism and the strong and weak nuclear forces. Predicted by quantum theory of gravity, gravitons have not yet been detected. | |
methanol | | | neutral particle | | | | CH3OH | | | | | | | | 1970 | | | | | | methyl alcohol | More rotational lines have been observed astronomically for it than for any other molecule. | |
molecular hydrogen | | | diatomic molecule | | | < 10000 K | H2 | | | | | | | | | | neutral particle | | | | | A molecule of hydrogen, discovered in interstellar space in 1970. H2 is a very hard molecule to detect. None of its transitions lie in the visible part of the spectrum. Second, being a symmetric homonuclear molecule, it does not have an electric-dipole rotation-vibration spectrum, and detection must be based on the weak quadrupole spectrum. Third, ultraviolet radiation is a very efficient dissociator of H2, so any H2 that survived would presumably be located inside very dense interstellar clouds. So far observations have borne out this supposition. Measurements of the region within about 1 kpc of the Sun suggest that H2 is about twice as abundant as atomic H. | |
molecular oxygen | | | neutral particle | | | < 10000 K | O2 | | | | | | | | | | | | | | | | |
neutrino | | | | antineutrino | | | | | | | | | | | | | massless particle | 0 | Fermi-Dirac statistics | 1/2 | | A stable particle with no charge, a rest mass of zero, and a spin of 1/2, that carries away energy in the course of nuclear reactions. Its main characteristic is the weakness of its interactions with all other particles. Since the wavelengths of neutrinos at the energies at which they are normally emitted from unstable nuclei are only a few thousandths of an angstrom (compared with the wavelength of a light photon which is several thousand angstroms), they have negligible probability (10-19 that of a light photon) of interacting with matter and escape at the speed of light. Neutrinos arise only in the energy-producing regions of stars and therefore, unlike light photons, provide direct evidence of conditions in stellar cores. There are two types of neutrinos, those associated with electrons (ve) and those associated with muons (vµ). | |
neutron | nucleus | | radioactive particle | | 3 | | | | | 15 minutes | | | proton, electron | | | two down quarks and one up quark | | 1.6749 × 10-24 g | Fermi-Dirac statistics | 1/2 | | Stable within the nucleus, the neutron if isolated decays, with a ha half-life of fifteen minutes. | the total energy produced when the particle decays |
photon | | | | | | | | physics | electromagnetism | | | | | | | | transverse wave | 0 | Bose-Einstein statistics | 1 | electromagnetic radiation | A transverse wave of electric and magnetic fields which can propagate through empty space. | |
pi0 | | | neutral particle | | 2 | | | | | -has source: Hopkins, J. 1976 Glossary of Astronomy and Astrophysics, University of Chicago Press | | | two γ-rays | | | | | 264 me | Bose-Einstein statistics | -has source: Hopkins, J. 1976 Glossary of Astronomy and Astrophysics, University of Chicago Press | π-meson | | |
positronium | | | boson | | | | | | | The average time in which a particle decays | | | the products produced immediately after decay | | | | | | Bose-Einstein statistics | integral | | A positron and electron bound together electrostaticaly. | the total energy produced when the particle decays |
water vapor | | | neutral particle | | | | H2O | | | | | | | | | | | | | | | | |