liquid ref D. Vieira et al ., Friedel oscillations in one dimensional metals From Luttinger s theorem ... charged particles can be observed, in the quantum mechanical scenario of Friedel Oscillations periodic ... gravitynlevity In the figure to the right, a 2 dimensional Friedel Oscillations has been illustrated ... in the wavelength of the Friedel Oscillations as a function of electron energy, an increase in wavelength ... Oscillations in 2D Electron Gas Systems at Semiconductor Surfaces , http www.brl.ntt.co.jp E activities ... 2009 06 02 friedel oscillations wherein we learn that the electron has a size a simple explanation of the phenomenon DEFAULTSORT Friedel Oscillations Category Condensed matter ... more details
Bloch oscillation is a phenomenon from solid state physics . It describes the oscillation of a particle e.g. an electron confined in a periodic potential when a constant force is acting on it. It was first pointed out by Bloch and Zener while studying the electrical properties of crystals. In particular, they predicted that the motion of electrons in a perfect crystal under the action of a constant electric field would be oscillatory instead of uniform. While in natural crystals this phenomenon is extremely hard to observe due to the scattering of electrons by lattice defects, it has been observed in semiconductor superlattices and in different physical systems such as cold atoms in an optical potential and ultrasmall Josephson junction s. Derivation The one dimensional equation of motion for an electron in a constant electric field E is math hbar frac dk dt eE math , which has the solution math k t k 0 frac eE hbar t math . The velocity v of the electron is given by math v k frac 1 hbar frac d mathcal E dk math , where math mathcal E k math denotes the dispersion relation for the given energy band . Suppose that the latter has the tight binding form math mathcal E k A cos ak math , where a is the lattice parameter and A is a constant. Then v k is given by math v k frac 1 hbar frac d mathcal E dk frac Aa hbar sin ak math , and the electron position math x math by math x t int v k t dt frac A eE cos left frac aeE hbar t right math . This shows that the electron oscillates in real space. The frequency of the oscillations is given by math omega B ae E hbar math . See also Super Bloch oscillations Category Fundamental physics concepts de Bloch Oszillationen ru uk ... more details
The term solar like oscillations refers to oscillation s in other star s that are excited in the same way as those in the Sun , namely by convection in its outer layers. See also asteroseismology helioseismology Variable star Solar like oscillations variable stars Procyon Oscillations controversy Procyon Space missions COROT , Kepler Mission Kepler , Microvariability and Oscillations of STars telescope MOST , Wide Field Infrared Explorer WIRE External links http whome.phys.au.dk jcd oscilnotes Lecture Notes on Stellar Oscillations published by J rgen Christensen Dalsgaard J. Christensen Dalsgaard Aarhus University , Denmark Category Variable stars Star Var star stub pt Oscila es do tipo solar ... more details
Subthreshold membrane potential oscillations are rhythmic fluctuations of the voltage difference between the interior and exterior of a neuron , in the nervous system . Neurons produce action potentials when their membrane potential increases past a critical threshold. If the voltage is below the threshold the neuron does not fire, but the membrane potential still fluctuates due to postsynaptic potential postsynaptic potentials and intrinsic electrical properties of neurons. In some type of neurons, the membrane potential can oscillation oscillate at specific frequencies. Although subthreshold oscillations do not directly result in neuronal firing, they may facilitate neural synchronization synchronous activity of neighboring neurons. It may also facilitate computation, particularly processing of sensory signals Overview Neurons display, beyond synapse synaptic and action potentials , rhythmic subthreshold membrane potential oscillations a particular type of neural oscillations . These oscillations , which resembled sinusoidal wave forms were originally discovered in the mammalian inferior olive nucleus cells. ref Llinas R. and Yarom Y. 1986 Oscillatory properties of guinea pig inferior ... ref The functional relevance of subthreshold oscillations concerns the nature of the intrinsic electrical ... D.1 Gloveli T. Behr J. Dugladze T.and Heinemann U. 1998 . Subthreshold membrane potential oscillations ... subthreshold membrane potential oscillations and low threshold spikes in rat entorhinal cortex ... Hasselmo Hasselmo M.E. 2007 . Temporal Frequency of Subthreshold Oscillations Scales with Entorhinal ... neurons exhibit heterogeneous subthreshold oscillations and spiking patterns PNAS 104 15911 15916 ref ... timing by intrinsic subthreshold oscillations in the olfactory bulb output neurons . J, Neuroscience ... Subthreshold oscillations generated by TTX sensitive sodium currents in dorsal cochlear nucleus pyramidal cells . Exp. Brain Research 153 443 451 ref The dynamic aspects of such oscillations have ... more details
Condensed matter experiments In condensed matter physics , Quantum oscillations describes an experimental physics experimental technique to map the Fermi surface of a metal in the presence of a strong magnetic field . ref name prsa cite journal last Coldea first Amalia title Quantum oscillations probe the normal electronic states of novel superconductors journal Philosophical Transactions of the Royal Society A year 2010 volume 368 pages 3503 3517 url http rsta.royalsocietypublishing.org content ... cite journal last Doiron Leyraud first Nicolas coauthors et al title Quantum oscillations and the Fermi ... of the magnetic field. In a quantum oscillations experiment, the external magnetic field is varied, which causes the Landau levels to pass over the Fermi surface, which in turn results in oscillations of the Quantum hall effect Hall resistance . ref name leyraud Observation of quantum oscillations ... 20fermi 20liquid&f false ref Quantum oscillations have been used to study high temperature superconductivity ... first Suchitra E. coauthors Neil Harrison, Gilbert G. Lonzarich title Quantum oscillations in the high ... 1687.full.pdf html accessdate 23 March 2012 ref File Quantum oscillations at 100 T.jpg 180px thumb ... is suppressed and Landau oscillations can be observed math varepsilon l frac eB m left ell frac 1 ... expand, and eventually fall off the Fermi surface. This leads to oscillations in the observed energy of the highest occupied level, and hence in the Hall conductivity. The periodicity of these oscillations ...&dq 22quantum oscillations 22 magnetic experimental techniques in physics&source bl&ots KNp1NXpCDs&sig ... ref If the axis of the magnetic field is varied at constant magnitude, similar oscillations are observed. The oscillations occur whenever the Landau orbits touch the Fermi surface. In this way, the complete ... first A. S. title Theory of quantum magneto oscillations in underdoped cuprate superconductors journal ... p473 1 accessdate 25 March 2012 ref However, quantum oscillations have been observed in these materials ... more details
Infobox journal title Nonlinear Oscillations cover editor Anatolii M. Samoilenko discipline Mathematics language English abbreviation publisher Springer Science Business Media on behalf of the Institute of Mathematics, National Academy of Sciences of Ukraine country Ukraine frequency Quarterly history 1998 present openaccess license impact 0.158 impact year 2010 website http imath.kiev.ua nosc web index.php?lang en link1 http www.springer.com mathematics dynamical systems journal 11072 link1 name Journal page on publisher s website link2 http www.springerlink.com openurl.asp?genre issue&issn 1536 0059&issue current link2 name Online access JSTOR OCLC LCCN CODEN ISSN 1536 0059 eISSN Nonlinear Oscillations is a quarterly Peer review peer reviewed mathematical journal that was established in 1998. It is published by Springer Science Business Media on behalf of the Institute of Mathematics, National Academy of Sciences of Ukraine . It covers research in the qualitative theory of differential or functional differential equation s. This includes the qualitative analysis of differential equations with the help of symbolic calculus systems and applications of the theory of ordinary and functional differential equations in various fields of mathematical biology, electronics, and medicine. Nonlinear Oscillations is a translation of the peer reviewed Ukraine Ukrainian journal Nelineinye Kolebaniya . The editor in chief is Anatoly M. Samoilenko Institute of Mathematics, National Academy of Sciences of Ukraine, Kiev, Ukraine . External links Official 1 http imath.kiev.ua nosc web index.php?lang en Category Mathematics journals Category Quarterly journals Category English language journals Category Springer academic journals Category Publications established in 1998 uk ... more details
Image BiSON Network.jpg 325px thumb The BiSON stations. The distribution in longitude allows for near continuous observations of the Sun. The Birmingham Solar Oscillations Network BiSON consists of a network of six remote solar observatories monitoring low degree Helioseismology solar oscillation modes. It is operated by the High Resolution Optical Spectroscopy group of the School of Physics and Astronomy at the University of Birmingham , United Kingdom UK , in collaboration with Sheffield Hallam University , United Kingdom UK . They are funded by the Science and Technology Facilities Council Science and Technology Facilities Council STFC . ref name BiSON Home cite web url http bison.ph.bham.ac.uk title BiSON Home accessdate 2009 05 16 ref The BiSON has been collecting data continuously on solar oscillations since 1976, making it the longest running helioseismology network with data covering three Solar cycle solar cycles . ref name BiSON PPT cite web url http astro.phys.au.dk SONG WORKSHOP 2006 Miller.ppt title BiSON The Birmingham Solar Oscillations Network accessdate 2009 05 16 ref Team Academic Staff Professor Yvonne Elsworth Head of project Professor Bill Chaplin Research Staff Anne Marie Broomhall Helioseismology Andrea Miglio Steven Hale Technical Staff Mr Ian Barnes Electronics Mr Barry Jackson Mechanic s Remote observatories BiSON operates automated Resonance resonant scattering spectrometer s in astronomical domes or mirror fed systems. The network was established in 1976 with two permanent stations the addition of several more sites culminated with the addition of a sixth in 1992. ref name 1996AAS cite journal date 05 1996 title Recent Results from the Birmingham Solar Oscillations Network BiSON journal American Astronomical Society publisher American Astronomical Society issue 1996AAS...188.6904C bibcode 1996AAS...188.6904C author1 Chaplin first1 W. J. last2 Elsworth first2 Y. last3 Isaak first3 G. R. last4 McLeod first4 C. P. last5 Miller ... more details
Lorentz violating neutrino oscillation refers to the quantum phenomenon of neutrino oscillations described ... of study. The conventional model of neutrino oscillations assumes that neutrinos are massive, which ... through the Lorentz violating neutrino oscillations Global models of neutrino oscillations with Lorentz ... of neutrinos explain the phenomenon of oscillations by endowing these particles with mass. However, if Lorentz violation occurs, oscillations could be due to other mechanisms. The general framework ... would affect neutrino propagation, interactions, and oscillations. This neutrino framework first appeared ... a discussion on Lorentz violating neutrino oscillations, was presented in a 1999 publication. ref name ... do indeed oscillate. These oscillations have a variety of possible implications, including ... oscillations Puma model puma model . The unconventional energy dependence in the theory leads ... last2 Liu first2 Zuowei last3 Nath first3 Pran ref of atmospheric neutrino oscillations require ... title Evidence for neutrino oscillations from the observation of Subatomic particle Electron antineutrino ... Cochran first6 A. last7 Donahue first7 J. last8 Fazely first8 A. last9 Garvey first9 G. ref oscillations ... of neutrino oscillations with Lorentz violation Global models are descriptions of neutrino oscillations ..., Challenging Lorentz noninvariant neutrino oscillations without neutrino masses , Phys. Lett. B 653 ... model for neutrino oscillations using Lorentz violation , Phys. Rev. D 74, 105009 2006 . http arxiv.org ... violating models for neutrino oscillations , http arxiv.org abs 1108.1799 arXiv 1108.1799 . ref ... neutrino to electron neutrino oscillations in MINOS , http arxiv.org abs 1108.0015 arXiv 1108.0015 ... oscillations of massless neutrinos are excluded , http arxiv.org abs 1106.6023 arXiv 1106.6023 ... antineutrino oscillations. This hamiltonian contains the information of propagation and oscillations ... because it does not contribute to oscillations however, it can play an important role in the stability ... more details
Cosmology cTopic Baryon Acoustic Oscillations Technical date September 2011 Expert subject Physics date September 2011 In cosmology , baryon acoustic oscillations BAO refers to regular, periodic fluctuations in the density of the visible baryonic matter of the universe, caused by Acoustics acoustic waves which existed in the early universe. ref name ref EisensteinNAR D.J. Eisenstein, New Astronomy Reviews. 49 , 360 2005 . ref In the same way that supernova experiments provide a standard candle for astronomical observations, ref name ref Perlmutter S. Perlmutter, et al. The Astrophysical Journal. 517 , 565 1999 . ref BAO matter clustering provides a standard ruler for length scale in cosmology. ref name ref EisensteinNAR The length of this standard ruler 490 million light years in today s universe ref name ref EisensteinAPJ D.J. Eisenstein et. al. The Astrophysical Journal. 633 , 560 2005 . ref can be measured by looking at the large scale structure of matter using astronomical surveys . ref name ref EisensteinAPJ BAO measurements help cosmologists understand more about the nature of dark energy the acceleration of the universe by constraining Lambda CDM model Parameters cosmological parameters . ref name ref EisensteinNAR The Early Universe The early universe consisted of a hot, dense Plasma physics plasma of electrons and baryons protons and neutrons . Photons light particles traveling ... are in the right most column. ref name ref MWhite M. White, Baryon acoustic oscillations and dark ... pressure . These counteracting forces of gravity and pressure create oscillations , analogous ... mwhite bao Martin White s Baryon Acoustic Oscillations and Dark Energy Web Page http www.cfa.harvard.edu ... http arxiv.org abs 0910.5224 Review of Baryon Acoustic Oscillations http www.sdss.org news releases 20050111.yardstick.html SDSS BAO Press Release DEFAULTSORT Baryon Acoustic Oscillations Category Physical cosmology Category Baryons de Baryonische akustische Oszillation fr Oscillations acoustiques ... more details
The Global Oscillation Network Group GONG is a community based program to study Sun solar Sun Structure internal structure and dynamics using helioseismology . Six solar observatories are involved, with the intention of achieving almost unbroken observation of the Sun. The six observatories are the Teide Observatory Canary Islands , the Learmonth Solar Observatory Western Australia , the Big Bear Solar Observatory California , the Mauna Loa Solar Observatory Hawaii , the Udaipur Solar Observatory India and the Cerro Tololo Inter American Observatory Chile . In 2001, the original GONG detectors were upgraded to 1000 x 1000 pixels and continuous magnetogram magnetograms were implemented, and the new system is known as GONG . More recently c. 2010 , improvements to GONG observatory instrumentation have been made to enable imaging of the H alpha H H alpha spectral line of hydrogen in the solar atmosphere. The GONG Program is managed by the National Solar Observatory, which is operated by AURA, Inc. under a cooperative agreement with the National Science Foundation External links http gong.nso.edu info GONG info at the National Solar Observatory site Category Sun Category Solar observatories sun stub zh ... more details
Transient noise pulses consist of a relatively short pulse followed by decaying low frequency oscillations. The initial peak is often due to an Impulse noise audio impulse interference , and the following oscillations are due to resonance on the channel that received the initial pulse. The source of these noise pulses is often channel interference. See also Transient acoustics Category Noise tech stub ... more details
orphan date March 2012 Oscillations are an important type of cell signaling characterized by the periodic change of the system in time. ref name Kruse & J licher. Oscillations in Biology. 2005 Kruse & J licher. Oscillations in Biology. 2005 ref Oscillations can take place in a biological system in a multitude of ways. Positive feedback loops , on their own or in combination with negative feedback are a common feature of oscillating biological systems. ref name Kholodenko. Cell signaling dynamics in time and space. 2006 Kholodenko. Cell signaling dynamics in time and space. 2006 ref Examples Genetic Oscillation One of the most common forms of biological oscillation is Oscillating gene genetic oscillation , which can take place when a transcription factor binds and represses its own Promoter genetics promoter . This type of regulatory system is able to successfully describe the NFkB NFkB IkB and p53 p53 Mdm52 biological oscillating systems. ref name Kruse & J licher. Oscillations in Biology. 2005 Relaxation Oscillations Relaxation oscillation takes place in the context of a bi stable system. It is characterized by the periodic switching between two stable states. ref name Kholodenko. Cell signaling dynamics in time and space. 2006 References reflist Category Cell signaling ... more details
Slow wave may refer to Oscillations of low frequency Slow wave potential Slow wave threshold of smooth muscle Slow wave sleep Slow wave coupler , a set of coupled microstrip lines Other Slow Wave , a comic strip disambig ... more details
NACA Report No. 787 A Theoretical Investigation of the Rolling Oscillations of an Airplane with Ailerons Free was issued by the United States National Advisory Committee for Aeronautics in June 1944. Introduction An analysis is made of the stability of an airplane with ailerons free, with particular attention to the motions when the ailerons have a tendency to float against the wind. The present analysis supersedes the aileron investigation contained in NACA Report No. 709 . The equations of motion are first written to include yawing and sideslipping, and it is demonstrated that the principal effects of freeing the ailerons can be determined without regard to these motions. If the ailerons tend to float against the wind and have a high degree of aerodynamic balance, rolling oscillations, in addition to the normal lateral oscillations, are likely to occur. On the basis of the equations including ... of the rolling oscillations in terms of the hinge moment derivates and other characteristics ... and damping of the rolling oscillations are found to be satisfactory in a mass balanced system so long ..., has an unfavorable effect on the damping of the oscillations and so shifts the boundary that close ... of the aileron free oscillations but in no case causes undamped oscillations if the ailerons are otherwise ... overbalanced, of oscillatory instability. The unstable oscillations exist in addition to the normal rolling yawing oscillations introduced by the dihedral angle and by the directional stability ... of the aileron free oscillations in a mass balanced system is so great as to make the oscillations appear ... with aileron chord. On the other hand, the oscillations are of considerably lower frequency for wide ... system has the effect of gradually increasing or decreasing the damping of the oscillations as their amplitude ... fixed. Neither instability or steady oscillations will result from the presence of friction. The stability of the control free oscillations is virtually independent of the moment of inertia ... more details
Spike and wave is the term that describes a particular pattern of the electroencephalogram EEG typically observed during Epilepsy epileptic seizures . Spike and wave patterns are seen in many types of epilepsy , and in particular during absence seizures also called petit mal seizures , which are characterized by clear cut spike and wave EEG oscillations. The mechanisms underlying spike and wave patterns are complex and involve cerebral cortex and thalamus, the intrinsic properties of the neurons, and the various types of synaptic receptors present in the circuits. In particular, it is thought that a diffuse increase in cortical excitability either through enhanced excitation or diminished inhibition can lead to spike and wave patterns through thalamocortical loops. In this case, the spike and wave patterns can be synchronous over large portions of the entire cerebral cortex generalized spike and wave seizures . A focal increase of excitability can also entrain the thalamocortical system or part of it to generate spike and wave patterns, and various types of focal seizures . References http www.scholarpedia.org article Spike and wave oscillations Spike and wave Oscillations article in Scholarpedia Neuroscience stub Category Neuroscience fr Pointes Ondes ... more details
The term SPACE capitalized can refer to Space TV channel SPACE , a Canadian science fiction channel The Society for Promotion of Alternative Computing and Employment DSPACE , a term in computational complexity theory Spectroscopic All Sky Cosmic Explorer , a proposed satellite designed to measure the baryon acoustic oscillations disambig ... more details
wiktionary starquake Starquake may refer to Starquake astrophysics , an astrophysical phenomenon when the crust of a neutron star undergoes a sudden adjustment Starquake video game , a 1984 computer game Starquake novel , a 1989 novel by Robert L. Forward See also asteroseismology for the study of pressure waves and oscillations within the atmospheres of stars disambig ... more details
BAO may refer to Bachelor of Medicine and Surgery Ireland Baccalaureus in Arte Obstetricia , Bachelor of Obstetrics, a medical degree unique to Ireland. Baryon acoustic oscillations , a signature of the early universe observed in galaxy surveys. Benny Anderssons Orkester Bullets And Octane See also Bao disambiguation disambig eo BAO fr BAO it BAO ... more details
QPO may stand for Qualified Petty Officer , a ranking in the Royal Canadian Sea Cadets Quasi periodic oscillations , a phenomenon exhibited by certain astronomical sources Qualified public offering , a stock offering that sets and meets requirements agreed upon between the investor and the stock issuer it usually involves a preferred stock series issue. disambig Category Initialisms fr QPO ... more details
cells lacking contact, the periodicity of these oscillations is rather variable 2 10 min . However, within an islet of Langerhans the oscillations become synchronized by electrical coupling between closely ... 6 min . ref name hellman Image Insulin oscillations coordination.svg thumb left 150px Coordination ... , the pancreas is connected to cranial nerve 10, and others, but the oscillations are accomplished ... into a common pancreatic rhythm. ref name hellman Clinical significance The insulin oscillations ... is a major insulin target. Disturbances of the insulin oscillations occur early in type 2 diabetes ... more details
The flywheel effect is the continuation of oscillations in an electronic oscillator oscillator Electronic circuit circuit after the control stimulus has been removed. This is usually caused by interacting inductor inductive and capacitor capacitive elements in the oscillator. Circuits undergoing such oscillations are said to be flywheeling . The flywheel effect may be desirable, such as in phase waves phase locked loops used in Synchronization synchronous systems, or undesirable, such as in voltage controlled oscillators. Flywheel effect is used in class C modulation where efficiency of modulation can be achieved as high as 90 . See also Thermal flywheel effect References FS1037C MS188 Category Electronics terms ... more details
Context date October 2009 one source date May 2010 Two sinusoidal oscillations of the same frequency are said to be mutually coherent if they exhibit a constant phase relationship during the course of time. See also Coherence physics Energy Phased array External links http www.ccr.jussieu.fr scbs b.htm Z.W.Wolkowski The Concept of Coherence Considered as a Systems Isomorphism physics stub Category Wave mechanics ... more details
sustainable oscillations. The second condition implies that, with adequate light input power, self sustained oscillations may be obtained without the need for the RF microwave amplifier in the loop ... more details
Asteroseismology studies the internal structure of our Sun and other stars using oscillations. These can ... id 1484 mode research research description id 333 Types of oscillations The modes of oscillations ... modes. Spherical modes are oscillations in the radial direction while toroidal modes oscillate horizontal ... as a special case of non radial ones, preserving the shape of the star in the oscillations, while the non ... 300px right An illustration of p mode oscillations in a spherical body. br R. Nilsson, MSc thesis ......325..725M title Nonradial oscillations of neutron stars author P. N. McDermott et al. year 1987 ... oscillations curvature, trapped and interface modes, with predicted periods in the range of microseconds ... On the non radial oscillations of a star. III A reconsideration of the axial modes author S. Chandrasekhar ... oscillations of neutron stars A new branch of strongly damped normal modes author M. Leins ... , High speed astrophysics Chasing neutron star oscillations. ref . More details on stellar pulsation ... gr qc 9909058 ref . Oscillation excitation Generally, oscillations are caused when a system is perturbed ... to that equilibrium state. The oscillations in neutron stars are probably weak with small amplitudes, but exciting these oscillations might increase the amplitudes to observable levels. One of the general ... hitting a bell. The hit adds energy to the system, which excites the amplitudes of the oscillations ... bibcode 1998ApJ...498L..45D title Global seismic oscillations in Soft Gamma Repeaters author R. Duncan ... condensate. This releases energy which partly could be channeled to excitations. Mode damping The oscillations ... to be in the range of years. When the kinetic energy of the oscillations is converted into thermal ... data about neutron star oscillations come from the blasts of four specific soft gamma repeater ... events have been observed, little is known for sure about neutron stars and the physics of their oscillations ... strasbg.fr abs 2005ApJ...628L..53I Discovery of rapid x ray oscillations in the tail of the SGR ... more details
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