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 Nucleon gold Collisions at 200A GeV Using Tagged D Au Interactions in the PHOBOS Detector written by and published by . This book was released on 2015 with total page 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 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 Relative Yields of Antiparticles to Particles in Au Au Collisions at 130 and 200 GeV Per Nucleon Pair written by Kristján Herlache Gulbrandsen and published by . This book was released on 2004 with total page 131 pages. Available in PDF, EPUB and Kindle. Book excerpt: Au+Au collisions at [square root of] [superscript]s nn = 130 and 200 GeV at the Relativistic Heavy Ion Collider have opened a new energy regime for studying nucleus-nucleus collisions. A search for the formation of a phase of matter in which quarks and gluons interact strongly over an extended deconfined volume is of primary importance. The PHOBOS detector was constructed to measure many observables at RHIC. The primary subsystem used in this analysis is the PHOBOS spectrometer. The spectrometer is a multiplane silicon pad detector which detects particles traversing its pads as they propagate through a strong magnetic field. The hit positions are used along with energy loss information in the silicon pads to determine both the momentum and velocity of the particles, allowing for the identification of the particle species. One of the most basic pieces of information to be determined is the baryochemical potential of the system. This information has been determined through the measurement of the relative yields of antiparticles to particles in RHIC collisions ... These values are compared to model predictions and are used to evaluate the contribution of baryon transport relative to particle production in determining the yields of baryon at midrapidity in central Au+Au collisions at RHIC energies.
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 Glauber Monte Carlo Study of 200 GeV U U Collisions at RHIC written by Christopher E. Flores and published by . This book was released on 2010 with total page 122 pages. Available in PDF, EPUB and Kindle. Book excerpt: Collisions of deformed uranium (238U) nuclei are studied using Glauber Monte-Carlo simulations in an effort to elucidate the effects of the non-symmetric rotations of prolate spheroid nucleus geometry and impact parameter. The nucleon density distribution is given by a three parameter Woods-Saxon density function and a Glauber Model is used in a Monte-Carlo simulation of U+U collisions. The number of participant nucleons and number of nucleon-nucleon collisions is determined and compared to the results found for gold using the same model. Simulations of uranium collisions shows that tip to tip U+U collisions increase energy density by 35% while body to body collisions decrease energy density by 10% compared to central Au+Au collisions. It is also shown that a cut on the top 5% of the charged multiplicity density per unit transverse area results in no significant increase or decrease in collision energy density. Finally, plots of predicted Upsilon production values show expected Upsilon production of collisions at various impact parameters and full overlap orientations.
Download or read book Study of Doubly Charged Delta Baryons in Collisions of Copper Nuclei at the Relativistic Heavy Ion Collider written by Joseph J. Simpson and published by . This book was released on 2017 with total page 59 pages. Available in PDF, EPUB and Kindle. Book excerpt: Experiments involving heavy-ion collisions at the Relativistic Heavy Ion Collider (RHIC) produce the hottest matter known to humans, approximately 100,000 times hotter than the center of the Sun or 7 trillion degrees Celsius. In these collisions, the nucleons melt into their constituent quarks and gluons for approximately 10 yoctoseconds (1E-23 seconds). As the collision system expands and cools, the quarks and gluons combine into particles via a process called “hadronization” and subsequently stream out into the detectors. Detailed studies of these produced particles can yield information about the properties of the medium in which they were produced. Some of the produced particles, known collectively as “resonances,” have lifetimes comparable to the lifetime of the collision medium itself. More specifically, comparative studies of the relative production of short-lived resonances and possible modifications of their properties by medium effects may provide information about the conditions present in and lifetime of the collision medium. In this project, we utilize data from 24.4 million collisions of copper nuclei at center-of-mass energies of 200 GeV per nucleon pair collected by the Solenoidal Tracker At RHIC (STAR) detector to reconstruct decays of the doubly-charged Delta baryon resonance and its anti-particle. Fits to the invariant mass distribution of Delta candidates are performed as functions of transverse momentum and collision centrality and properties of the Delta resonances are extracted statistically. Specifically we look at the mass, the width, and the yield of this resonance. Comparisons of our results with previous studies from proton on proton collisions and deuteron on gold nucleus collisions, as well as with model calculations, may provide deeper insight into effects present in the collision medium as well as the lifetime of the medium itself.
Download or read book Charged Kaon Production in P p and D Au Collisions the Baseline Comparison Systems for Understanding Au Au Collisions at RHIC written by Camelia M. Mironov and published by . This book was released on 2005 with total page 90 pages. Available in PDF, EPUB and Kindle. Book excerpt: One of the primary challenges in modern nuclear physics is to understand the properties of hot nuclear matter. The expectation is that at sufficiently high energy densities, nuclear matter undergoes a phase transition where individual nucleons 'dissolve' and a plasma of freely moving quarks and gluons is formed. To accomplish this in the laboratory, normal nuclear matter is heated and compressed through collisions of heavy nuclei at relativistic energies. The Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory is a dedicated particle accelerator, capable of colliding nuclear beams to energies up to 100 GeV per nucleon per beam. Particle species ranging from protons (A =1) to gold (A =197) are accelerated in this state-of-the-art facility and collide at selected intersection points. In this dissertation, a detailed transverse momentum (p T) analysis is made at central rapidities, using the STAR Time Projection Chamber (TPC). The data set is comprised of about 10 million d+Au and about 6 million p+p events at 200 GeV. Previously analyzed data from a 2002 Au+Au run are also used. This work concentrates on the study of identified charged kaons (K +, K - ), which are the lightest strange mesons and hence the particles that dominate strangeness production. Charged kaons are identified using a topological reconstruction method which has relatively large p T coverage. In this dissertation, we present p T and yield systematics. We find that the particle to anti-particle ratio is p T independent in all colliding systems studied, an indication that in the p T range studied, the pQCD regime is not reached yet. The ratios, close to unity, signal a rather net-baryon-free mid-rapidity region. The in central d+Au collisions is larger than in peripheral Au+Au collisions, which might hint at the presence of 'Cronin effect' in the dAu system as explained. We also obtain results on nuclear modification factors (R dA CP - central to peripheral ratio, R dA, R AA - geometrically scaled Au+Au(d+Au) to p+p ratios) which are presented for various mesons and baryons. In d+Au collisions, an enhancement compared to binary scaling of both R dA CP and R dA is observed, an experimental observation called 'Cronin effect'. This result is thought to be an initial-state effect. In contrast, the same ratio in central Au+Au collisions exhibits a suppression instead of an enhancement. This was understood in terms of a dense partonic medium which induces energy loss via gluon radiation by a high-energy parton traversing the medium, and leads, after fragmentation, to hadrons with lower . The meson-baryon differences, first observed in Au+Au R AA CP, also exist in d+Au collisions.
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 Azimuthal Anisotropy in Gold gold Collisions at 4 5 GeV Center of mass Energy Per Nucleon Pair Using Fixed target Mode at the Relativistic Heavy Ion Collider written by Yang Wu and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Pseudorapidity Dependence of Directed and Elliptic Flow in Au Au Collisions at 19 6 62 4 130 and 200 GeV Per Nucleon Pair written by Joshua Brian Hamblen and published by . This book was released on 2006 with total page 248 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Deutron Photodissociation in Ultraperipheral Relativistic Heavyion on Deutron Collisions written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In ultraperipheral relativistic deuteron on heavy-ion collisions, a photon emitted from the heavy nucleus may dissociate the deuterium ion. We find deuterium breakup cross sections of 1.24 barns for deuterium-gold collisions at a center of mass energy of 200 GeV per nucleon, as studied at the Relativistic Heavy Ion Collider, and 2.35 barns for deuterium-lead collisions at a center of mass energy of 6.2 TeV, as proposed for the Large Hadron Collider. In the latter case, the cross section is as large as that of hadronic interactions. The estimated error is 5%. We discuss the use of this process as a luminosity monitor and a 'tag' for moderate impact parameter collisions.
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 Nucleus nucleus Collisions at Very High Energies written by and published by . This book was released on 1990 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 Strangelet Search in S W Collisions at 200 A GeV c Per Nucleon written by Werner Volken and published by . This book was released on 1994 with total page 90 pages. Available in PDF, EPUB and Kindle. Book excerpt:
