42,772 articles
R CrA
R CrA, or R Coronae Australis, is a young, strongly variable Herbig Ae/Be star at the heart of the Coronet cluster in the Corona Australis star-forming region.
R Dor
R Doradus is a nearby red giant star in Dorado, the closest oxygen-rich AGB star to the Sun, whose surface convection was tracked by ALMA in 2023.
R Hya
R Hydrae (R Hya) is a Mira variable red giant in Hydra, the third Mira discovered in 1704, with a period that shortened from 495 to 389 days.
R Leo
R Leonis (R Leo) is a Mira-type variable star in Leo, a red giant whose brightness swings between magnitudes 5.4 and 10.5 over about 310 days.
R Monocerotis
R Monocerotis (R Mon) is a young, variable Herbig Ae/Be star of roughly 8 solar masses in Monoceros, about 2,500 light-years away, illuminating NGC 2261, Hubble's Variable Nebula.
R Scuti
R Scuti (R Sct) is a bright RV Tauri variable star in Scutum, discovered in 1795, pulsating with alternating deep and shallow minima and one of the longest observed records.
R-curve
An R-curve, or crack growth resistance curve, is a fracture mechanics plot of a material's resistance to crack extension against stable crack growth, proposed by Irwin and Kies in the 1950s.
R-hadron
An R-hadron is a hypothetical composite particle in which a long-lived gluino or squark binds with ordinary quarks or gluons; none has been observed, though LHC searches set multi-TeV mass limits.
R-matrix method
The R-matrix method is a numerical technique of atomic collision physics that partitions configuration space into inner and outer regions to compute scattering cross sections.
r-mode instability
The r-mode instability is a gravitational-wave driven instability of the rotating-fluid oscillations called r-modes, which are unstable at any nonzero spin rate if viscous damping is weak.
R-parity
R-parity, also known as matter-parity, is a discrete symmetry in supersymmetric extensions of the Standard Model that prevents rapid proton decay and makes the lightest supersymmetric particle a dark matter candidate.
R-process
The r-process, or rapid neutron-capture process, is a nucleosynthesis mechanism creating about half of all heavy elements beyond iron, confirmed in neutron-star mergers in 2017.
R-symmetry
R-symmetry is an internal symmetry of a supersymmetric theory that does not commute with supersymmetry, acting on supercharges and Grassmann parameters of superfields; in N=1 theories it is U(1)R.
R-value (insulation)
R-value, also called thermal insulance, is a measure of thermal resistance used to rate insulation; the higher the value, the slower heat moves through the material.
R. Benny Gerber
R. Benny Gerber is an Israeli-born theoretical and computational chemist at the Hebrew University of Jerusalem and UC Irvine, known for VSCF methods and predicted noble-gas molecules.
R. Brent Tully
R. Brent Tully, born 1943 in Toronto, is an American-based astronomer at the University of Hawaii known for the Tully–Fisher relation, the Cosmicflows catalogs, and mapping the Laniakea Supercluster.
R. Bruce Weisman
R. Bruce Weisman is a Rice University chemist who mapped the optical spectra of single-walled carbon nanotubes, developed methods to sort them, and founded Applied NanoFluorescence.
R. Dennis Cook
R. Dennis Cook, also published as R. D. Cook, is an American statistician and University of Minnesota professor emeritus known for Cook's distance and sufficient dimension reduction.
R. Graham Cooks
R. Graham Cooks is an American analytical chemist at Purdue University known for ambient ionization mass spectrometry, elected to the National Academy of Sciences in 2015.
R. H. Bing
R. H. Bing (1914–1986) was an American mathematician known for work in geometric topology, especially 3-manifolds and decomposition theory, elected to the National Academy of Sciences in 1965.
R. J. Dwayne Miller
R. J. Dwayne Miller is a chemist and physicist at the University of Toronto who pioneered ultrabright femtosecond electron sources recording atomic movies of molecules in motion.
R. Jürgen Behm
R. Jürgen Behm is a chemist who pioneered atomic-scale scanning tunneling microscopy of surface processes, then researched electrocatalysis and energy storage as professor at Ulm University from 1992 to 2020.
R. L. Moore
R. L. Moore, born Robert Lee Moore, was an American mathematician at the University of Texas known for point-set topology, a term he coined, and the Moore method.
R. Lawrence Edwards
Richard Lawrence Edwards, known as R. Lawrence or Larry Edwards, is an American isotope geochemist at the University of Minnesota who developed modern uranium-thorium dating of climate records.
R. Leonard Brooks
R. Leonard Brooks, full name Rowland Leonard Brooks, was an English mathematician at Trinity College, Cambridge, known for Brooks's theorem on graph coloring and for work on squaring the square.
R. M. Foster
R. M. Foster, born Ronald Martin Foster (1896–1998), was an American mathematician at AT&T and Bell Labs known for the 1924 reactance theorem, a first breakthrough in network synthesis.
R. Morris Bullock
R. Morris Bullock is an American organometallic chemist at Pacific Northwest National Laboratory who directs the Center for Molecular Electrocatalysis and develops cheap-metal electrocatalysts for hydrogen.
R. P. C. Morgan
R. P. C. Morgan (Royston Philip Charles Morgan, born 1942) is a British geomorphologist specializing in soil erosion, author of the standard textbook Soil Erosion and Conservation and co-developer of the MMF model.
R. Paul Butler
R. Paul Butler is an astronomer at Carnegie Science who co-developed the iodine-cell technique for Doppler spectroscopy and co-discovered hundreds of exoplanets, including 5 of the first 6 known.
R. Stephen Berry
R. Stephen Berry (1931–2020) was an American chemical physicist and University of Chicago professor known for the Berry pseudorotation, cluster science, finite-time thermodynamics, and early energy policy analysis.