Download or read book Charged Hadron Spectra in Au Au Collisions at centre of mass Energy Per Nucleon Pair written by Manuel Calderón de la Barca Sánchez and published by . This book was released on 2001 with total page 340 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Charged Hadron Transverse Momentum Spectra in Au Au and D Au Collisions at 200 GeV Per Nucleon Pair written by Jay Lawrence Kane and published by . This book was released on 2005 with total page 235 pages. Available in PDF, EPUB and Kindle. Book excerpt: (Cont.) When ... is calculated for different rapidities, a suppression is seen as the rapidity in the deuteron fragmentation region increases. This has been predicted to be seen if a CGC does form in the colliding nuclei.
Download or read book Inclusive Charged Hadron Transverse Momentum Spectra at Center of Mass Energy of 200 GeV for P p and D Au Collisions at the Relativistic Heavy Ion Collider written by Jonathan Edward Gans and published by . This book was released on 2004 with total page 288 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Using the Balance Function to Search for Late Hadronization in Au Au Collisions at a Center of Mass Energy of 130 GeV Per Nucleon Pair written by Marguerite Belt Tonjes and published by . This book was released on 2002 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Suppression of High Transverse Momentum Charged Hadrons in Au Au Collisions at 200 GeV Nucleon Nucleon Center of Mass Energy written by Jason B. Bryslawskyj and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Charged Kaon Production in Au Au Collisions at center of mass Energy Per Nucleon Pair written by Wensheng Deng and published by . This book was released on 2002 with total page 162 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Studies of Nucleon gold Collisions at 200 GeV Per Nucleon Pair Using Tagged D Au Interactions written by Corey James Reed and published by . This book was released on 2006 with total page 215 pages. Available in PDF, EPUB and Kindle. Book excerpt: (Cont.) Further, hadron production in p+Au interactions is compared to that of n+Au interactions. The single charge difference between a p+Au and a n+Au collision allows for a unique study of the ability of the interaction to transport the proton from the initial deuteron to mid-rapidity. However, no asymmetry between the positively and negatively charged hadron spectra of p+Au and n+Au interactions is observed at (qr) = 0.8. Collision centrality was determined using several different observables, including those based on the multiplicity in different regions of pseudorapidity and those based on the amount of nuclear spectator material. It is shown that measurements made on small collision systems in the mid-rapidity region are biased by centrality variables based on the mid-rapidity multiplicity. Despite this bias, a smooth evolution with centrality is observed in the Cronin enhancement of hadrons produced in d+Au collisions. It is shown that this smooth progression is independent of the choice of centrality variable when centrality is parametrized by the multiplicity measured near mid-rapidity.
Download or read book Directed and Elliptic Flow in Au Au Collisions at a Center of Mass Energy of 19 6 GeV Per Nucleon nucleon Pair written by Michael George Anderson and published by . This book was released on 2006 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Neutral Kaon Correlations in Au au Collisions at Center of Mass Energy of 200 GeV Per Nucleon Pair written by Selemon Bekele and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: A few microseconds after the Big Bang, the universe is believed to have existed in the form of a plasma composed of strongly interacting particles known as quarks and gluons. Although the quarks and gluons behave as asymptotically free particles in a Quark Gluon Plasma (QGP), free quarks and gluons have never been discovered in the laboratory. Experiments at the Relativistic Heavy Ion Collider (RHIC) aim to create conditions similar to the early universe by colliding heavy ions at the highest energies possible in the hope of observing a phase transition from a QGP into hadronic degrees of freedom. The response of the space time structure of the hot reaction zone created in a heavy ion collision to a phase transition is one of the many observables being studied at RHIC. Making use of the techniques of two particle intensity interferometry, also known as the HBT effect, the RHIC experiments are studying the space-time structure and dynamical properties of the region from which particles are emitted. A large spatial size and long duration of particle emission are the predicted signals for a phase transition from a QGP to a hadronic phase. In this thesis we present results on the first measurement of one dimensional K0[subscript s] K0[subscript s] interferometry by the STAR experiment at RHIC in central (small impact parameter) Au-Au collisions at center of mass energy of 200 GeV per nucleon pair. The lambda parameter, which is a measure of the sources chaoticity, is found to be consistent with unity confirming the fact that the source is mostly chaotic as measured by STAR using three particle correlations. Without taking into account the effect of the strong interaction, the invariant radius R inv is found to be large for the mean transverse mass M [subscript t] of the pair, which is about 980 MeV/c, compared to expectations from charged pion correlations at the same M [subscript t]. Including the effect of the strong interactions makes the radius parameter for the K0[subscript s] K0[subscript s] system fall within the charged pion M [subscript t] systematics. Our result serves as a valuable cross-check of charged pion measurements which are mainly affected by contributions from resonance decays and final state interactions. This is also an important first step towards a full three dimensional analysis of neutral kaon correlations as high statistics data from RHIC will be available in the near future.
Download or read book Hadron Spectra in Au Au Collisions at the BNL AGS written by Michael David Heffner and published by . This book was released on 2000 with total page 298 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Identified Particle Transverse Momentum Distributions from AU AU Collisions at 62 4 GeV Per Nucleon Pair written by Conor Henderson and published by . This book was released on 2005 with total page 322 pages. Available in PDF, EPUB and Kindle. Book excerpt: Transverse momentum (PT) distributions for pions, kaons, protons and antiprotons have been measured near mid-rapidity for Au+Au collisions at sNN = 62.4 GeV using the PHOBOS detector at the Relativistic Heavy-Ion Collider (RHIC) in Brookhaven National Laboratory. Particle identification is performed using the PHOBOS Time-of-Flight plastic scintillator walls and specific energy loss in the multi-layer silicon Spectrometer, which is also used for track reconstruction and momentum-determination. The spectra are corrected for all detector-dependent effects, including feed-down from weak decays. At PT 3 GeV/c, protons are measured to be the dominant species of charged hadrons and scale much faster with respect to collision centrality than mesons. This behaviour at 62.4 GeV is found to be remarkably similar to that observed in Au+Au collisions at 200 GeV, an interesting observation which should serve as an important constraint on the various mechanisms which have been proposed to describe particle production over this PT range. Baryon stopping, the transport of baryon number from intial beam rapidity, is explored through the net proton (p - p) yields at mid-rapidity. These results fill a large gap between the SPS and higher RHIC energies and as such form an important set of data for comparing to models of baryon transport mechanisms.
Download or read book Measurements of Dielectron Production in Au Au Collisions at math mrow msqrt msub mi mi mrow mi N mi mi N mi mrow msub msqrt mo written by and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We report on measurements of dielectron (ee−) production in Au+Au collisions at a center-of-mass energy of 200 GeV per nucleon-nucleon pair using the STAR detector at RHIC. Systematic measurements of the dielectron yield as a function of transverse momentum (pT) and collision centrality show an enhancement compared to a cocktail simulation of hadronic sources in the low invariant-mass region (Mee
Download or read book First Moment of Azimuthal Anisotropy in Au Au Collisions from the Beam Energy Scan at the Relativistic Heavy Ion Collider written by Prashanth Shanmuganathan and published by . This book was released on 2016 with total page 128 pages. Available in PDF, EPUB and Kindle. Book excerpt: Excited nuclear matter at high temperature and density results in the creation of a new state of matter called Quark Gluon Plasma (QGP). It is believed that the Universe was in the QGP state a few millionths of a second after the Big Bang. A QGP can be experimentally created for a very brief time by colliding heavy nuclei, such as gold, at ultra-relativistic energies. The Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory consists of two circular rings, 3.8 km in circumference, which can accelerate heavy nuclei in two counter-rotating beams to nearly the speed of light (up to 100 GeV per beam). STAR (Solenoidal Tracker At RHIC) is one of two large detectors at the RHIC facility, and was constructed and is operated by a large international collaboration made up of more than 500 scientists from 56 institutions in 12 countries. STAR has been taking data from heavy ion collisions since the year 2000. An important component of the physics effort of the STAR collaboration is the Beam Energy Scan (BES), designed to study the properties of the Quantum Chromodynamics (QCD) phase diagram in the regions where a first-order phase transition and a critical point may exist. Phase-I of the BES program took data in 2010, 2011 and 2014, using Au+Au collisions at a center-of-mass energy per nucleon pair of 7.7, 11.5, 14.5, 19.6, 27 and 39 GeV. It is by now considered a well-established fact that the QGP phase exists. However, all evidence so far indicates that there is a smooth crossover when normal hadronic matter becomes QGP and vice versa in collisions at the top energy of RHIC (and likewise at the Large Hadron Collider at the CERN laboratory in Switzerland). At these very high energies, the net density of baryons like nucleons is quite low, since there are almost equal abundances of baryons and antibaryons. It is known that net-baryon compression increases as the beam energy is lowered below a few tens of GeV. Of course, if the beam energy is too low, then the QGP phase cannot be produced at all, so it has been proposed that there is an optimum beam energy, so far unknown, where phenomena like a first-order phase transition and a critical point might be observed. On the other hand, there also exists the possibility that a smooth crossover to QGP occurs throughout the applicable region of the QCD phase diagram. Experiments are needed to resolve these questions. In this dissertation, I focus on one of the main goals of the BES program, which is to search for a possible first-order phase transition from hadronic matter to QGP and back again, using measurements of azimuthal anisotropy. The momentum-space azimuthal anisotropy of the final-state particles from collisions can be expressed in Fourier harmonics. The first harmonic coefficient is called directed flow, and reflects the strength of the collective sideward motion, relative to the beam direction, of the particles. Models tell us that directed flow is imparted during the very early stage of a collision and is not much altered during subsequent stages of the collision. Thus directed flow can provide information about the early stages when the QGP phase exists for a short time. A subset of hydrodynamic and nuclear transport model calculations with the assumption of a first-order phase transition show a prominent dip in the directed flow versus beam energy. I present directed flow and its slope with respect to rapidity, for identified particle types, namely lambda, anti-lambda and kaons as a function of beam energy for central, intermediate and peripheral collisions. The production threshold of neutral strange particles requires them to be created earlier, and these particles have relatively long mean free path. Thus these particles may probe the QGP at earlier times. In addition, new Lambda measurements can provide more insight about baryon number transported to the midrapidity region by stopping process of the nuclear collision. It is noteworthy that net-baryon density (equivalent to baryon chemical potential) depends not only on beam energy but also on collision centrality. The centrality dependence of directed flow and its slope are also studied for all BES energies for nine identified particle types, lambda, anti-lambda, neutral kaons, charged kaons, protons, anti-protons, and charged pions. These detailed results for many particle species, where both centrality and beam energy are varied over a wide range, strongly constrain models. The measurements summarized above pave the way for a new round of model refinements and subsequent comparisons with data. If the latter does not lead to a clear conclusion, the BES Phase-II program will take data in 2019 and 2020 with an upgraded STAR detector with wider acceptance, greatly improved statistics, and will extend measurements to new energy points.
Download or read book Quark Confinement and the Hadron Spectrum V written by N. Brambilla and published by World Scientific. This book was released on 2003 with total page 551 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides an update on our understanding of strong interaction, with theoretical and experimental highlights included. It is divided into five sections. The first section is devoted to the investigations into and the latest results on the mechanism of quark confinement. The second and third sections focus respectively on light and heavy quarks (effective field theories, SchwingerOCoDyson approach and lattice QCD results). The fourth section deals with the deconfinement mechanism and quarkOCogluon plasma formation signals. The last section presents highlights of experiments, new physics beyond QCD, and nonperturbative approaches in other theories (strings and SUSY) that may be useful in QCD."
Download or read book Direct Photon Hadron Correlations Measurement in Au Au Collision at Nucleon Center of mass Energy of 200 GeV with Isolation Cut Methods written by and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Quark Confinement And The Hadron Spectrum V Proceedings Of The 5th International Conference written by Nora Serafina Brambilla and published by World Scientific. This book was released on 2003-08-27 with total page 551 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides an update on our understanding of strong interaction, with theoretical and experimental highlights included. It is divided into five sections. The first section is devoted to the investigations into and the latest results on the mechanism of quark confinement. The second and third sections focus respectively on light and heavy quarks (effective field theories, Schwinger-Dyson approach and lattice QCD results). The fourth section deals with the deconfinement mechanism and quark-gluon plasma formation signals. The last section presents highlights of experiments, new physics beyond QCD, and nonperturbative approaches in other theories (strings and SUSY) that may be useful in QCD.
Download or read book MEASUREMENT OF CHARGED HADRON SPECTRA IN AU AU COLLISION AT SNN written by and published by . This book was released on 2005 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt:
