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PHENIX Detector
The PHENIX detector (for Pioneering High Energy Nuclear Interaction eXperiment) is the largest of the four experiments that have taken data at the Relativistic Heavy Ion Collider (RHIC) in Brookhaven National Laboratory, United States. Overview PHENIX is an exploratory experiment for the investigation of high energy collisions of heavy ions and protons, and is designed specifically to measure direct probes of the collisions such as electrons, muons, and photons. The primary goal of PHENIX is to discover and study a new state of matter called quark–gluon plasma (QGP). Detecting and understanding the QGP allows us to understand better the universe in the moments after the Big Bang. The PHENIX Experiment consists of a collection of detectors, each of which perform a specific role in the measurement of the results of a heavy ion collision. The detectors are grouped into two central arms, which are capable of measuring a variety of particles including pions, protons, kaons, deuteron ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Relativistic Heavy Ion Collider
The Relativistic Heavy Ion Collider (RHIC ) is the first and one of only two operating heavy-ion colliders, and the only spin-polarized proton collider ever built. Located at Brookhaven National Laboratory (BNL) in Upton, New York, and used by an international team of researchers, it is the only operating particle collider in the US. By using RHIC to collide ions traveling at relativistic speeds, physicists study the primordial form of matter that existed in the universe shortly after the Big Bang. By colliding spin-polarized protons, the spin structure of the proton is explored. RHIC is as of 2019 the second-highest-energy heavy-ion collider in the world. As of November 7, 2010, the Large Hadron Collider (LHC) has collided heavy ions of lead at higher energies than RHIC. The LHC operating time for ions (lead–lead and lead–proton collisions) is limited to about one month per year. In 2010, RHIC physicists published results of temperature measurements from earlier experime ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kaon
KAON (Karlsruhe ontology) is an ontology infrastructure developed by the University of Karlsruhe and the Research Center for Information Technologies in Karlsruhe. Its first incarnation was developed in 2002 and supported an enhanced version of RDF ontologies. Several tools like the graphical ontology editor OIModeler or the KAON Server were based on KAON. There are ontology learning companion tools which take non-annotated natural language text as input: TextToOnto (KAON-based) and Text2Onto (KAON2-based). Text2Onto is based on the Probabilistic Ontology Model (POM). In 2005, the first version of KAON2 was released, offering fast reasoning support for OWL ontologies. KAON2 is not backward-compatible with KAON. KAON2 is developed as a joint effort of the Information Process Engineering (IPE) at the Research Center for Information Technologies (FZI), the Institute of Applied Informatics and Formal Description Methods (AIFB) at the University of Karlsruhe, and the Information Ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nuclear Physics A
''Nuclear Physics A'', ''Nuclear Physics B'', ''Nuclear Physics B: Proceedings Supplements'' and discontinued ''Nuclear Physics'' are peer-reviewed scientific journals published by Elsevier. The scope of ''Nuclear Physics A'' is nuclear and hadronic physics, and that of ''Nuclear Physics B'' is high energy physics, quantum field theory, statistical systems, and mathematical physics. ''Nuclear Physics'' was established in 1956, and then split into ''Nuclear Physics A'' and ''Nuclear Physics B'' in 1967. A supplement series to ''Nuclear Physics B'', called ''Nuclear Physics B: Proceedings Supplements'' has been published from 1987 onwards. ''Nuclear Physics B'' is part of the SCOAP3 initiative. Abstracting and indexing ''Nuclear Physics A'' * Current Contents ''Current Contents'' is a rapid alerting service database from Clarivate Analytics, formerly the Institute for Scientific Information and Thomson Reuters. It is published online and in several different printed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quantum Chromodynamics
In theoretical physics, quantum chromodynamics (QCD) is the theory of the strong interaction between quarks mediated by gluons. Quarks are fundamental particles that make up composite hadrons such as the proton, neutron and pion. QCD is a type of quantum field theory called a non-abelian gauge theory, with symmetry group SU(3). The QCD analog of electric charge is a property called ''color''. Gluons are the force carriers of the theory, just as photons are for the electromagnetic force in quantum electrodynamics. The theory is an important part of the Standard Model of particle physics. A large body of experimental evidence for QCD has been gathered over the years. QCD exhibits three salient properties: * Color confinement. Due to the force between two color charges remaining constant as they are separated, the energy grows until a quark–antiquark pair is spontaneously produced, turning the initial hadron into a pair of hadrons instead of isolating a color charge. Although ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Barbara Jacak
Barbara Jacak () is a nuclear physicist who uses heavy ion collisions for fundamental studies of hot, dense nuclear matter. She is director of the Nuclear Science Division, Lawrence Berkeley National Laboratory, and a professor of physics at UC Berkeley. Before going to Berkeley, she was a member of the Department of Physics and Astronomy at Stony Brook University, where she held the rank of distinguished professor. She is a leading member of the collaboration that built and operates the PHENIX detector, one of the large detectors that operated at the Relativistic Heavy Ion Collider at Brookhaven National Laboratory, and was involved in the discovery of the quark gluon plasma and its strongly coupled, liquid-like behavior. Throughout her career she has served on many advisory committees and boards, including the National Research Council Committee on Nuclear Physics, and the ''Physical Review C'' editorial board. Physics career Jacak started her career at Michigan State Universi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
William Allen Zajc
William Allen Zajc is a U.S. physicist and the I.I. Rabi Professor of Physics at Columbia University in New York, USA, where he has worked since 1987. Early life Born in Barstow, California, on November 14, 1953, and raised in Brookfield, Wisconsin, he received his bachelor's degree from the California Institute of Technology in 1975. He went on to the doctoral program in physics at the University of California, Berkeley, where, as his thesis topic, he became the first person to use Hanbury-Brown Twiss correlations to measure the size of the interacting region between two colliding heavy ions. Career From 1982 to 1986 he was first a post-doctoral fellow and then a professor at the University of Pennsylvania. In 1987 he accepted a professorship at Columbia University, where he has remained as a professor ever since. He has been a scientific leader in the field of heavy ion physics since early in his career, and he has performed extensive service for the broader nuclear physic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shoji Nagamiya
A is a door, window or room divider used in traditional Japanese architecture, consisting of translucent (or transparent) sheets on a lattice frame. Where light transmission is not needed, the similar but opaque ''fusuma'' is used (oshiire/closet doors, for instance). Shoji usually slide, but may occasionally be hung or hinged, especially in more rustic styles. Shoji are very lightweight, so they are easily slid aside, or taken off their tracks and stored in a closet, opening the room to other rooms or the outside. Fully traditional buildings may have only one large room, under a roof supported by a post-and-lintel frame, with few or no permanent interior or exterior walls; the space is flexibly subdivided as needed by the removable sliding wall panels. The posts are generally placed one '' tatami''-length (about 2 m or 6 ft) apart, and the shoji slide in two parallel wood-groove tracks between them. In modern construction, the shoji often do not form the exterior ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deuteron
Deuterium (or hydrogen-2, symbol or deuterium, also known as heavy hydrogen) is one of two stable isotopes of hydrogen (the other being protium, or hydrogen-1). The nucleus of a deuterium atom, called a deuteron, contains one proton and one neutron, whereas the far more common protium has no neutrons in the nucleus. Deuterium has a natural abundance in Earth's oceans of about one atom of deuterium among all atoms of hydrogen (see heavy water). Thus deuterium accounts for approximately 0.0156% by number (0.0312% by mass) of all the naturally occurring hydrogen in the oceans, while protium accounts for more than 99.98%. The abundance of deuterium changes slightly from one kind of natural water to another (see Vienna Standard Mean Ocean Water). (Tritium is yet another hydrogen isotope, with two neutrons, that is far more rare and is radioactive.) The name ''deuterium'' is derived from the Greek , meaning "second", to denote the two particles composing the nucleus. Deuteri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proton
A proton is a stable subatomic particle, symbol , H+, or 1H+ with a positive electric charge of +1 ''e'' elementary charge. Its mass is slightly less than that of a neutron and 1,836 times the mass of an electron (the proton–electron mass ratio). Protons and neutrons, each with masses of approximately one atomic mass unit, are jointly referred to as "nucleons" (particles present in atomic nuclei). One or more protons are present in the nucleus of every atom. They provide the attractive electrostatic central force which binds the atomic electrons. The number of protons in the nucleus is the defining property of an element, and is referred to as the atomic number (represented by the symbol ''Z''). Since each element has a unique number of protons, each element has its own unique atomic number, which determines the number of atomic electrons and consequently the chemical characteristics of the element. The word ''proton'' is Greek for "first", and this name was given to the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brookhaven National Laboratory
Brookhaven National Laboratory (BNL) is a United States Department of Energy national laboratory located in Upton, Long Island, and was formally established in 1947 at the site of Camp Upton, a former U.S. Army base and Japanese internment camp. Its name stems from its location within the Town of Brookhaven, approximately 60 miles east of New York City. It is managed by Stony Brook University and Battelle Memorial Institute. Research at BNL includes nuclear and high energy physics, energy science and technology, environmental and bioscience, nanoscience, and national security. The 5,300 acre campus contains several large research facilities, including the Relativistic Heavy Ion Collider and National Synchrotron Light Source II. Seven Nobel Prizes have been awarded for work conducted at Brookhaven Lab. Overview BNL is staffed by approximately 2,750 scientists, engineers, technicians, and support personnel, and hosts 4,000 guest investigators every year. The laboratory has ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pion
In particle physics, a pion (or a pi meson, denoted with the Greek letter pi: ) is any of three subatomic particles: , , and . Each pion consists of a quark and an antiquark and is therefore a meson. Pions are the lightest mesons and, more generally, the lightest hadrons. They are unstable, with the charged pions and decaying after a mean lifetime of 26.033 nanoseconds ( seconds), and the neutral pion decaying after a much shorter lifetime of 85 attoseconds ( seconds). Charged pions most often decay into muons and muon neutrinos, while neutral pions generally decay into gamma rays. The exchange of virtual pions, along with vector, rho and omega mesons, provides an explanation for the residual strong force between nucleons. Pions are not produced in radioactive decay, but commonly are in high-energy collisions between hadrons. Pions also result from some matter–antimatter annihilation events. All types of pions are also produced in natural processes wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Big Bang
The Big Bang event is a physical theory that describes how the universe expanded from an initial state of high density and temperature. Various cosmological models of the Big Bang explain the evolution of the observable universe from the earliest known periods through its subsequent large-scale form. These models offer a comprehensive explanation for a broad range of observed phenomena, including the abundance of light elements, the cosmic microwave background (CMB) radiation, and large-scale structure. The overall uniformity of the Universe, known as the flatness problem, is explained through cosmic inflation: a sudden and very rapid expansion of space during the earliest moments. However, physics currently lacks a widely accepted theory of quantum gravity that can successfully model the earliest conditions of the Big Bang. Crucially, these models are compatible with the Hubble–Lemaître law—the observation that the farther away a galaxy is, the faster it is mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
