All articles starting with G
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Gamma Geminorum
Gamma Geminorum, or Alhena, is a spectroscopic binary star in Gemini about 109 light-years from Earth, the third brightest point of light in the constellation after Pollux and Castor.
Gamma globulin
Gamma globulin (γ globulin) is the electrophoretic serum fraction containing most immunoglobulins; source of Cohn fraction II immune globulin used for hepatitis A prophylaxis and IVIG/SCIG antibody replacement therapy.
Gamma irradiation
Gamma irradiation is a sterilization method using cobalt-60 gamma rays to kill microorganisms on medical devices, pharmaceuticals, and tissue grafts, typically at a dose of 25 kGy.
Gamma Knife surgery
Gamma Knife surgery is a stereotactic radiosurgery method in which about 192 cobalt-60 sources converge on a brain target with submillimeter accuracy, treating tumors, AVMs, and trigeminal neuralgia.
Gamma Leporis
Gamma Leporis is an F-type main-sequence star about 29 light-years from the Sun in the constellation Lepus, the brighter component of a wide double star with an orange dwarf companion.
Gamma matrices
The gamma matrices, or Dirac matrices, are square matrices satisfying the Clifford anticommutation relation {γ, γ} = 2η, appearing as coefficients of the Dirac equation in relativistic quantum mechanics.
Gamma motor neuron
A gamma motor neuron, also called a fusimotor neuron, is a lower motor neuron of the spinal cord or brainstem that innervates muscle spindle intrafusal fibers and regulates spindle sensitivity.
Gamma Ophiuchi
Gamma Ophiuchi, cataloged as HD 161868, is a rapidly rotating A0V main-sequence star in Ophiuchus about 103 light-years away, known for one of the largest resolved debris disks around a nearby star.
Gamma Orionis
Gamma Orionis, officially named Bellatrix, Latin for "the Female Warrior", is a hot blue giant star in Orion, its third brightest, about 250 light years from Earth.
Gamma Pavonis
Gamma Pavonis is an F-type main-sequence star in the southern constellation Pavo, about 30 light-years away, notable for its low metallicity, old age, and asteroseismic studies.
Gamma Pegasi
Gamma Pegasi, or Algenib, is a blue subgiant star of spectral type B2 IV in the constellation Pegasus, about 391.5 light-years from Earth, and a hybrid pulsating variable.
Gamma prime
Gamma prime (γ′) is the ordered intermetallic precipitate, based on Ni₃(Al, Ti), that is the principal strengthening phase in nickel-based superalloys for jet-engine turbine disks and blades.
Gamma process
The gamma process, or gamma subordinator, is a Lévy process with independent, nonnegative gamma-distributed increments, applied in reliability and as the time change behind the Variance Gamma option-pricing model.
Gamma ray
A gamma ray, also called gamma radiation, is the most energetic, shortest-wavelength electromagnetic radiation, emitted by excited atomic nuclei during radioactive decay and used in cancer therapy.
Gamma Ray (band)
Gamma Ray is a German power metal band formed in 1989 in Hamburg by ex-Helloween guitarist Kai Hansen; debut Heading for Tomorrow (1990), landmark Land of the Free (1995), Teutonic sound pillar with ten albums by 2010.
Gamma rays
Gamma rays are the highest-energy photons of the electromagnetic spectrum, a penetrating ionizing radiation described by Paul Villard in 1900 and emitted by nuclear processes, gamma-ray bursts, and pulsars.
Gamma regression
Gamma regression is a generalized linear model for strictly positive, right-skewed continuous outcomes such as costs and insurance claims, with variance proportional to the squared mean.
Gamma Serpentis
Gamma Serpentis, or Ainalhai, is a yellow-white F-type main-sequence star in the Serpens Caput half of the constellation Serpens, about 36.7 light-years away, with roughly 1.2 solar masses.
Gamma spectroscopy
Gamma spectroscopy, also called gamma ray spectrometry, is an analytical technique that identifies radionuclides by their characteristic gamma ray energies and quantifies their activity, using high-resolution detectors like HPGe.
Gamma Tauri
Gamma Tauri is a K-type giant star in the Hyades, the nearest open cluster to Earth, one of four prominent K giants that dominate its bright end.
Gamma titanium aluminide
Gamma titanium aluminide (γ-TiAl) is a lightweight intermetallic alloy with a density of about 4 g/cm³ that retains strength at 650–850 °C, used in jet engine turbine blades.
Gamma tubulin
Gamma tubulin (γ-tubulin), tubulin family protein discovered 1989 in Aspergillus nidulans; with GCPs forms γTuSC and γTuRC ring complexes that template microtubule nucleation at centrosomes and non-centrosomal sites; also regulates mitosis, cell cycle, and DNA damage response.
Gamma Ursae Majoris
Gamma Ursae Majoris, formally named Phecda, is a white A-type star about 83 light-years from Earth, marking the lower-left corner of the Big Dipper's bowl.
Gamma Velorum
Gamma Velorum is a bright multiple star system in the constellation Vela whose brightest component, γ² Velorum, is a 78.5-day binary containing the closest Wolf–Rayet star to the Sun.
Gamma Virginis
Gamma Virginis, also known as Porrima, is a naked-eye binary star in Virgo made of two nearly identical F0 stars about 38 light-years away, orbiting each other every 169 years.
Gamma wave
Gamma wave: brain rhythm in the gamma band, roughly 30–90 Hz (definitions vary to 30–150 Hz), first named by Jasper and Andrews in 1938; generated by pyramidal cell–parvalbumin interneuron interactions, linked to attention, memory, and Alzheimer's research.
Gamma World
Gamma World: post-apocalyptic science fantasy tabletop RPG, first published by TSR in 1978 (James M. Ward, Gary Jaquet); seven editions, mutants on Gamma Terra, card-based 7th edition (2010).
Gamma-alumina
Gamma-alumina (γ-Al2O3) is a metastable transition alumina with a defect spinel structure, formed by calcining boehmite at about 450–750 °C and the dominant industrial catalyst support for hydrotreating and automotive converters.
Gamma-aminobutyric acid transaminase deficiency
Gamma-aminobutyric acid transaminase deficiency, also called GABA-T or GABA transaminase deficiency, is an ultra-rare autosomal recessive ABAT-gene disorder causing neonatal epileptic encephalopathy, hypotonia, choreoathetosis, accelerated growth, and elevated CSF GABA.
Gamma-Butyrolactone
Gamma-butyrolactone, also known as GBL or 1,4-butyrolactone, is a cyclic ester and widely used industrial solvent, notably in semiconductor manufacturing, that the body rapidly converts to the depressant GHB, placing it under controlled-substance regulation.