All-Heavy Tetraquarks

Total Page:16

File Type:pdf, Size:1020Kb

All-Heavy Tetraquarks PHYSICAL REVIEW D 100, 016006 (2019) All-heavy tetraquarks † ‡ Ming-Sheng Liu,1,4,* Qi-Fang Lü,1,4, Xian-Hui Zhong,1,4, and Qiang Zhao2,3,4,§ 1Department of Physics, Hunan Normal University, and Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education, Changsha 410081, China 2Institute of High Energy Physics and Theoretical Physics Center for Science Facilities, Chinese Academy of Sciences, Beijing 100049, China 3School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China 4Synergetic Innovation Center for Quantum Effects and Applications (SICQEA), Hunan Normal University, Changsha 410081, China (Received 21 January 2019; published 16 July 2019) In this work, we study the mass spectra of the all-heavy tetraquark systems, i.e., ccc¯c¯, bbb¯b¯, bbc¯c=cc¯ b¯b¯, bcc¯c=cc¯ b¯c¯, bcb¯b=bb¯ b¯c¯, and bcb¯c¯, within a potential model by including the linear confining potential, Coulomb potential, and spin-spin interactions. It shows that the linear confining potential has important contributions to the masses and is crucial for our understanding of the mass spectra of the all-heavy ¯ ¯ tetraquark systems. For the all-heavy tetraquarks Q1Q2Q3Q4, our explicit calculations suggest that ¯ ¯ no bound states can be formed below the thresholds of any meson pairs ðQ1Q3Þ − ðQ2Q4Þ or ¯ ¯ ðQ1Q4Þ − ðQ2Q3Þ. Thus, we do not expect narrow all-heavy tetraquark states to be existing in experiments. DOI: 10.1103/PhysRevD.100.016006 I. INTRODUCTION constituent quarks are confined inside these Zc or Zb states, it makes them the best candidates for QCD exotic hadrons. Experimental searches for and theoretical studies of Recently, the tetraquarks of all-heavy systems, such as exotic hadrons beyond the conventional quark model are ¯¯ ¯ ¯ an important test of nonperturbative properties of the strong cccc and bbbb, have received considerable attention with interaction theory QCD. Since the discovery of quark model the development of experiments. If there are stable tetra- quark ccc¯c¯ and/or bbb¯b¯ states, they are most likely to be [1] and QCD, the progresses on the experimental tools have ¯ ¯ brought to us a lot of novel phenomena in hadron physics. In observed at LHC [9]. In fact, a search for the tetraquark bbbb particular, during the past 15 years, there have been a states is being carried out by the LHCb Collaboration sizeable number of candidates for QCD exotics [2–8]. although no confirmed information has been observed Interestingly, but also puzzlingly, it shows that the number [10]. Other study interests for physicists arise from the of exotic candidates is far less than what we have expected special aspects of the all-heavy tetraquark systems [11]. for the hadron spectroscopy, where the internal effective They may favor to form genuine tetraquark configurations degrees of freedom of a hadron may contain quarks and rather than loosely bound hadronic molecules, since the light gluons beyond the conventional quark model prescription. mesons cannot be exchanged between two heavy mesons. Strong evidences for such exotic hadrons include some Furthermore, it will be very easy to distinguish the all-heavy of those recently observed XYZ states, e.g., Xð3872Þ, tetraquark states from the states which have been observed because their masses should be far away from the mass Zcð3900Þ, Zcð4020Þ, Zbð10610Þ, and Zbð10650Þ [2].In particular, these charged quarkoniumlike states, Z and Z , regions of the observed states. Thus, besides some previous c b – contain not only the hidden heavy flavor cc¯ or bb¯, but also works on the heavy tetraquark states [12 17],manynew – charged light flavors of ud¯ or du¯. Since at least four studies have been carried out in recent years [11,18 30], although some of the conclusions are quite different from each other. In some works, it is predicted that there exist *[email protected] † stable bound tetraquark ccc¯c¯ states and/or bound tetraquark [email protected] ‡ ¯ ¯ [email protected] bbbb states with relatively smaller masses below the thresh- §[email protected] olds of heavy charmonium pairs [11,21–28]. Thus, their decays into heavy quarkonium pairs through quark rear- Published by the American Physical Society under the terms of rangements will be hindered. In contrast, in some other the Creative Commons Attribution 4.0 International license. works, it is predicted that there should be no stable bound Further distribution of this work must maintain attribution to ¯ ¯ the author(s) and the published article’s title, journal citation, tetraquark ccc¯c¯ and bbbb states [12,16,18,29,30] because and DOI. Funded by SCOAP3. the predicted masses are large enough for them to decay into 2470-0010=2019=100(1)=016006(12) 016006-1 Published by the American Physical Society LIU, LÜ, ZHONG, and ZHAO PHYS. REV. D 100, 016006 (2019) ¯ ¯ heavy quarkonium pairs. To some extent, a better under- confinement for the four-quark system Q1Q2Q3Q4,we standing of the possible mass locations is not only crucial for have 12 configurations as follows: understanding their underlying dynamics, but also useful for 6 ¯ ¯ 6¯ 0 6 ¯ ¯ 6¯ 0 experimental searches for their existence. j1i¼j½Q1Q21½Q3 Q41i0; j2i¼jfQ1Q2g0fQ3 Q4g0i0; In this work, we systemically study the mass spectra of ¯ ¯ 3 3¯ ¯ ¯ 3 0 4 3¯ ¯ ¯ 3 0 the all-heavy tetraquark Q1Q2Q3Q4 systems with a poten- j i¼jfQ1Q2g1fQ3 Q4g1i0; j i¼j½Q1Q20½Q3 Q40i0; – 6 ¯ ¯ 6¯ 0 6 ¯ ¯ 6¯ 0 tial model widely used in the literature [31 49].Our j5i¼j½Q1Q21½Q3 Q41i1; j6i¼j½Q1Q21fQ3 Q4g0i1; purpose is to understand two key issues based on the 7 6 ¯ ¯ 6¯ 0 8 3¯ ¯ ¯ 3 0 knowledge collected in the study of heavy quarkonium j i¼jfQ1Q2g0½Q3 Q41i1; j i¼jfQ1Q2g1fQ3 Q4g1i1; spectrum. The first one is what a quark potential model can 3¯ ¯ ¯ 3 0 3¯ ¯ ¯ 3 0 j9i¼jfQ1Q2g1½Q3 Q40i1; j10i¼j½Q1Q20fQ3 Q4g1i1; tell about the all-heavy tetraquark system. The second one 6 ¯ ¯ 6¯ 0 3¯ ¯ ¯ 3 0 is where the masses of the ground states could be located if j11i¼j½Q1Q21½Q3 Q41i2; j12i¼jfQ1Q2g1fQ3 Q4g1i2; the all-heavy tetraquark states do exist. At this moment, we do not consider any orbital or radial where fg and ½ denote the symmetric and antisymmetric excitations of the all-heavy tetraquarks. Instead, we would flavor wave functions of the two quarks (antiquarks) sub- like to address where and how the all-heavy tetraquarks systems, respectively. The subscripts and superscripts are the would manifest themselves in their lowest states. For a spin quantum numbers and representations of the color spectrum of multiquark states, a correct identification of the SU(3) group, respectively. A symmetric spatial wave func- ground state should be the first step towards a better tion is implied for the ground states under investigation. ¯ understanding of the multiquark dynamics in the non- It should be emphasized that for the bcbc¯ systems the perturbative regime. J ¼ 1 states can have both C ¼1, which can be con- The potentials between the quarks, such as the linear structed by the linear combinations of j6i, j7i, j9i and j10i, confining potential, color Coulomb potential, and spin-spin 1 interactions, are adopted the standard forms of the potential 0 6 ¯ 6¯ 0 6 ¯ 6¯ 0 j6 i¼pffiffiffi ðjðbcÞ1ðbc¯Þ0i1 − jðbcÞ0ðbc¯Þ1i1Þ; ð1Þ models. The model parameters are determined by fitting the 2 mass spectra of charmonium, bottomonium, and Bc meson. 1 ¯ ¯ In our calculations, we find both the confining potential and j70i¼pffiffiffi ðjðbcÞ6ðb¯c¯Þ6i0 þjðbcÞ6ðb¯c¯Þ6i0Þ; ð2Þ color Coulomb potential are very crucial for understanding 2 1 0 1 0 1 1 the masses of the all-heavy tetraquarks. The linear confining 1 potential as well as the kinetic energy contributes a quite large 90 ffiffiffi 3¯ ¯ ¯ 3 0 − 3¯ ¯ ¯ 3 0 ¯ ¯ j i¼p ðjðbcÞ1ðbcÞ0i1 jðbcÞ0ðbcÞ1i1Þ; ð3Þ positive mass term to the all-heavy tetraquarks Q1Q2Q3Q4, 2 which leads to a large mass far above the threshold of the ¯ ¯ ¯ ¯ 1 meson pair Q1Q3 − Q2Q4 or Q1Q4 − Q2Q3, although the 0 3¯ ¯ 3 0 3¯ ¯ 3 0 j10 i¼pffiffiffi ðjðbcÞ1ðbc¯Þ0i1 þjðbcÞ0ðbc¯Þ1i1Þ; ð4Þ color Coulomb potential contributes a very large negative 2 mass term. As a consequence, we find no bound all-heavy ¯ ¯ 60 90 −1 70 tetraquarks Q1Q2Q3Q4 below the threshold of any meson where configurations j i and j i have C ¼ , and j i ¯ − ¯ ¯ − ¯ and j100i have C ¼þ1. Since the permutation symmetries pairs Q1Q3 Q2Q4 or Q1Q4 Q2Q3. ¯ The paper is organized as follows: a brief introduction to are lost for the bc and bc¯ subsystems, in this work, we use the framework is given in Sec. II. In Sec. III, the numerical () to denote no permutation symmetries for these quark pair results and discussions are presented. A short summary is subsystems. given in Sec. IV. In Table I, all possible configurations and corresponding quantum numbers for the ccc¯c¯, bbb¯b¯, bbc¯c¯, bcc¯c¯, bcb¯b¯, ¯ II. FRAMEWORK and bcbc¯ systems are listed. A. Quark model classification B. Hamiltonian for the multiquark system In the charm and bottom quark sector, there are nine ¯ ¯ ¯¯ ¯ ¯ ¯¯ The following nonrelativistic Hamiltonian is adopted for different all-heavy Q1Q2Q3Q4 systems: cccc, bbbb, bccc, ¯ ¯ the calculation of the masses of the all-heavy Q1Q2Q3Q4 bcb¯b¯, bbc¯c¯, bcb¯c¯, ccb¯c¯, bbb¯c¯, and ccb¯b¯. Note that ccb¯c¯, system: bbb¯c¯, and ccb¯b¯ are the antiparticles of bcc¯c¯, bcb¯b¯, and ¯¯ bbcc, respectively. Thus, we need only consider six X4 X ¯¯ ¯ ¯ ¯¯ ¯ ¯ ¯¯ ¯ ¯ systems, cccc, bbbb, bccc, bcbb, bbcc, and bcbc,in H ¼ mi þ Ti − TG þ VijðrijÞ; ð5Þ our calculations.
Recommended publications
  • Observation of Global Hyperon Polarization in Ultrarelativistic Heavy-Ion Collisions
    Available online at www.sciencedirect.com Nuclear Physics A 967 (2017) 760–763 www.elsevier.com/locate/nuclphysa Observation of Global Hyperon Polarization in Ultrarelativistic Heavy-Ion Collisions Isaac Upsal for the STAR Collaboration1 Ohio State University, 191 W. Woodruff Ave., Columbus, OH 43210 Abstract Collisions between heavy nuclei at ultra-relativistic energies form a color-deconfined state of matter known as the quark-gluon plasma. This state is well described by hydrodynamics, and non-central collisions are expected to produce a fluid characterized by strong vorticity in the presence of strong external magnetic fields. The STAR Collaboration at Brookhaven National Laboratory’s√ Relativistic Heavy Ion Collider (RHIC) has measured collisions between gold nuclei at center of mass energies sNN = 7.7 − 200 GeV. We report the first observation of globally polarized Λ and Λ hyperons, aligned with the angular momentum of the colliding system. These measurements provide important information on partonic spin-orbit coupling, the vorticity of the quark-gluon plasma, and the magnetic field generated in the collision. 1. Introduction Collisions of nuclei at ultra-relativistic energies create a system of deconfined colored quarks and glu- ons, called the quark-gluon plasma (QGP). The large angular momentum (∼104−5) present in non-central collisions may produce a polarized QGP, in which quarks are polarized through spin-orbit coupling in QCD [1, 2, 3]. The polarization would be transmitted to hadrons in the final state and could be detectable through global hyperon polarization. Global hyperon polarization refers to the phenomenon in which the spin of Λ (and Λ) hyperons is corre- lated with the net angular momentum of the QGP which is perpendicular to the reaction plane, spanned by pbeam and b, where b is the impact parameter vector of the collision and pbeam is the beam momentum.
    [Show full text]
  • Light Higgs Production in Hyperon Decay
    Light Higgs Production in Hyperon Decay Xiao-Gang He∗ Department of Physics and Center for Theoretical Sciences, National Taiwan University, Taipei. Jusak Tandean† Department of Mathematics/Physics/Computer Science, University of La Verne, La Verne, CA 91750, USA G. Valencia‡ Department of Physics and Astronomy, Iowa State University, Ames, IA 50011, USA (Dated: July 8, 2018) Abstract A recent HyperCP observation of three events in the decay Σ+ pµ+µ− is suggestive of a new particle → with mass 214.3 MeV. In order to confront models that contain a light Higgs boson with this observation, it is necessary to know the Higgs production rate in hyperon decay. The contribution to this rate from penguin-like two-quark operators has been considered before and found to be too large. We point out that there are additional four-quark contributions to this rate that could be comparable in size to the two-quark contributions, and that could bring the total rate to the observed level in some models. To this effect we implement the low-energy theorems that dictate the couplings of light Higgs bosons to hyperons at leading order in chiral perturbation theory. We consider the cases of scalar and pseudoscalar Higgs bosons in the standard model and in its two-Higgs-doublet extensions to illustrate the challenges posed by existing experimental constraints and suggest possible avenues for models to satisfy them. arXiv:hep-ph/0610274v3 16 Apr 2008 ∗Electronic address: [email protected] †Electronic address: [email protected] ‡Electronic address: [email protected] 1 I. INTRODUCTION Three events for the decay mode Σ+ pµ+µ− with a dimuon invariant mass of 214.3 0.5 MeV → ± have been recently observed by the HyperCP Collaboration [1].
    [Show full text]
  • Mass Generation Via the Higgs Boson and the Quark Condensate of the QCD Vacuum
    Pramana – J. Phys. (2016) 87: 44 c Indian Academy of Sciences DOI 10.1007/s12043-016-1256-0 Mass generation via the Higgs boson and the quark condensate of the QCD vacuum MARTIN SCHUMACHER II. Physikalisches Institut der Universität Göttingen, Friedrich-Hund-Platz 1, D-37077 Göttingen, Germany E-mail: [email protected] Published online 24 August 2016 Abstract. The Higgs boson, recently discovered with a mass of 125.7 GeV is known to mediate the masses of elementary particles, but only 2% of the mass of the nucleon. Extending a previous investigation (Schumacher, Ann. Phys. (Berlin) 526, 215 (2014)) and including the strange-quark sector, hadron masses are derived from the quark condensate of the QCD vacuum and from the effects of the Higgs boson. These calculations include the π meson, the nucleon and the scalar mesons σ(600), κ(800), a0(980), f0(980) and f0(1370). The predicted second σ meson, σ (1344) =|ss¯, is investigated and identified with the f0(1370) meson. An outlook is given on the hyperons , 0,± and 0,−. Keywords. Higgs boson; sigma meson; mass generation; quark condensate. PACS Nos 12.15.y; 12.38.Lg; 13.60.Fz; 14.20.Jn 1. Introduction adds a small additional part to the total constituent- quark mass leading to mu = 331 MeV and md = In the Standard Model, the masses of elementary parti- 335 MeV for the up- and down-quark, respectively [9]. cles arise from the Higgs field acting on the originally These constituent quarks are the building blocks of the massless particles. When applied to the visible matter nucleon in a similar way as the nucleons are in the case of the Universe, this explanation remains unsatisfac- of nuclei.
    [Show full text]
  • Pentaquark and Tetraquark States Arxiv:1903.11976V2 [Hep-Ph]
    Pentaquark and Tetraquark states 1 2 3 4;5 6;7;8 Yan-Rui Liu, ∗ Hua-Xing Chen, ∗ Wei Chen, ∗ Xiang Liu, y Shi-Lin Zhu z 1School of Physics, Shandong University, Jinan 250100, China 2School of Physics, Beihang University, Beijing 100191, China 3School of Physics, Sun Yat-Sen University, Guangzhou 510275, China 4School of Physical Science and Technology, Lanzhou University, Lanzhou 730000, China 5Research Center for Hadron and CSR Physics, Lanzhou University and Institute of Modern Physics of CAS, Lanzhou 730000, China 6School of Physics and State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871, China 7Collaborative Innovation Center of Quantum Matter, Beijing 100871, China 8Center of High Energy Physics, Peking University, Beijing 100871, China April 2, 2019 Abstract The past seventeen years have witnessed tremendous progress on the experimental and theo- retical explorations of the multiquark states. The hidden-charm and hidden-bottom multiquark systems were reviewed extensively in Ref. [1]. In this article, we shall update the experimental and theoretical efforts on the hidden heavy flavor multiquark systems in the past three years. Espe- cially the LHCb collaboration not only confirmed the existence of the hidden-charm pentaquarks but also provided strong evidence of the molecular picture. Besides the well-known XYZ and Pc states, we shall discuss more interesting tetraquark and pentaquark systems either with one, two, three or even four heavy quarks. Some very intriguing states include the fully heavy exotic arXiv:1903.11976v2 [hep-ph] 1 Apr 2019 tetraquark states QQQ¯Q¯ and doubly heavy tetraquark states QQq¯q¯, where Q is a heavy quark.
    [Show full text]
  • The Quark Model and Deep Inelastic Scattering
    The quark model and deep inelastic scattering Contents 1 Introduction 2 1.1 Pions . 2 1.2 Baryon number conservation . 3 1.3 Delta baryons . 3 2 Linear Accelerators 4 3 Symmetries 5 3.1 Baryons . 5 3.2 Mesons . 6 3.3 Quark flow diagrams . 7 3.4 Strangeness . 8 3.5 Pseudoscalar octet . 9 3.6 Baryon octet . 9 4 Colour 10 5 Heavier quarks 13 6 Charmonium 14 7 Hadron decays 16 Appendices 18 .A Isospin x 18 .B Discovery of the Omega x 19 1 The quark model and deep inelastic scattering 1 Symmetry, patterns and substructure The proton and the neutron have rather similar masses. They are distinguished from 2 one another by at least their different electromagnetic interactions, since the proton mp = 938:3 MeV=c is charged, while the neutron is electrically neutral, but they have identical properties 2 mn = 939:6 MeV=c under the strong interaction. This provokes the question as to whether the proton and neutron might have some sort of common substructure. The substructure hypothesis can be investigated by searching for other similar patterns of multiplets of particles. There exists a zoo of other strongly-interacting particles. Exotic particles are ob- served coming from the upper atmosphere in cosmic rays. They can also be created in the labortatory, provided that we can create beams of sufficient energy. The Quark Model allows us to apply a classification to those many strongly interacting states, and to understand the constituents from which they are made. 1.1 Pions The lightest strongly interacting particles are the pions (π).
    [Show full text]
  • RIKEN BNL Research Center Workshop Volume 108
    BNL-97035-2012 F onnal Report Proceedings of RIKEN BNL Research Center Workshop Volume 108 Hyperon-Hyperon Interactions and Searches for Exotic Di-Hyperons in Nuclear Collisions February 29 - March 2,2012 Organizers: Anthony Baltz, Rainer Fries, Huan Zhong Huang, John Millener and Zhangbu Xu RIKEN BNL Research Center ' Building 510A, Brookhaven National Laboratory, Upton, NY 11973-5000, USA DISCLAIMER This work was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, nor any of their contractors, subcontractors or their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or any third party's use or the results of such use of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof or its contractors or subcontractors. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof Notice: This manuscript has been authored by employees of Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CHI0886 with the U.S. Department of Energy. The . publisher by accepting the manuscript for publication acknowledges that the United States Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form of this manuscript, or allow others to do so, for United States Government purposes.
    [Show full text]
  • Hyperon-Nucleon Interaction, Hypernuclei & Hyperonic Matter
    Hyperon-nucleon interaction, hypernuclei & hyperonic matter Isaac Vidaña Universidade de Coimbra “Interaction forte dans la matière nucléaire: nouvelles tendaces” Ecole Internationale Joliot-Curie, 27 Sept.- 3 Oct. 2009, Lacanau (France) Plan of the Lecture Introduction & Historical Overview Birth, Life & Death of Hypernuclei Hyperon-Nucleon Interaction Hypernuclear Matter & Neutron Star Properties What is a hyperon ? A hyperon is a baryon made of one , two or three strange quarks Hyperon Quarks I(JP) Mass (MeV) Λ uds 0(1/2+) 1115 Σ+ uus 1(1/2+) 1189 Σ0 uds 1(1/2+) 1193 Σ- dds 1(1/2+) 1197 Ξ0 uss 1/2(1/2+) 1315 Ξ- dss 1/2(1/2+) 1321 Ω- sss 0(3/2+) 1672 What is a hypernucleus ? A hypernucleus is a bound system of nucleons with one or more strange baryons (Λ,Σ,Ξ,Ω- hyperons). H. Bando, PARITY 1, 54 (1986) In a simple single-particle model: protons, neutrons and hyperons are considered distinguishable particles placed in independent effective potential wells in which 12 Pauli exclusion principle is applied. Simple s.p. model of " C ! Since hyperons are distinguishable from nucleons, they are privileged probes to explore states deep inside the nucleus, extending our knowledge of conventional to flavored nuclear physics. ΛΛ Hyperons can change the nuclear nuclear structure. For instance the glue-like role of the Λ hyperon can facilitate the existance of neutron-rich hypernuclei, being a more suitable framework to study matter with extreme n/p ratios as compared to ordinary nuclei. A hypernucleus is a “laboratory” to study hyperon-nucleon (YN) and hyperon-hyperon (YY) interactions.
    [Show full text]
  • Unveiling the Strong Interaction Among Hadrons at the LHC
    Article Unveiling the strong interaction among hadrons at the LHC https://doi.org/10.1038/s41586-020-3001-6 ALICE Collaboration* Received: 3 June 2020 Accepted: 20 October 2020 One of the key challenges for nuclear physics today is to understand from frst Published online: 9 December 2020 principles the efective interaction between hadrons with diferent quark content. First successes have been achieved using techniques that solve the dynamics of Open access quarks and gluons on discrete space-time lattices1,2. Experimentally, the dynamics of Check for updates the strong interaction have been studied by scattering hadrons of each other. Such scattering experiments are difcult or impossible for unstable hadrons3–6 and so high-quality measurements exist only for hadrons containing up and down quarks7. Here we demonstrate that measuring correlations in the momentum space between hadron pairs8–12 produced in ultrarelativistic proton–proton collisions at the CERN Large Hadron Collider (LHC) provides a precise method with which to obtain the missing information on the interaction dynamics between any pair of unstable hadrons. Specifcally, we discuss the case of the interaction of baryons containing strange quarks (hyperons). We demonstrate how, using precision measurements of proton–omega baryon correlations, the efect of the strong interaction for this hadron–hadron pair can be studied with precision similar to, and compared with, predictions from lattice calculations13,14. The large number of hyperons identifed in proton–proton collisions at the LHC, together with accurate modelling15 of the small (approximately one femtometre) inter-particle distance and exact predictions for the correlation functions, enables a detailed determination of the short-range part of the nucleon-hyperon interaction.
    [Show full text]
  • Quarks, Pion, Kaons, and Hyperons Garrett Yar N Claremont Mckenna College
    Claremont Colleges Scholarship @ Claremont CMC Senior Theses CMC Student Scholarship 2017 Maximum Mass Restraint of Neutron Stars: Quarks, Pion, Kaons, and Hyperons Garrett yaR n Claremont McKenna College Recommended Citation Ryan, Garrett, "Maximum Mass Restraint of Neutron Stars: Quarks, Pion, Kaons, and Hyperons" (2017). CMC Senior Theses. 1535. http://scholarship.claremont.edu/cmc_theses/1535 This Open Access Senior Thesis is brought to you by Scholarship@Claremont. It has been accepted for inclusion in this collection by an authorized administrator. For more information, please contact [email protected]. 1 Maximum Mass Restraint of Neutron Stars: Quarks, Pion, Kaons, and Hyperons A Thesis Presented by Garrett Dane Ryan To the Keck Science Department Of Claremont McKenna, Pitzer, and Scripps Colleges In partial fulfillment of The degree of Bachelor of Arts Senior Thesis in Physics 12-05-16 2 Table of Contents Introduction and Neutron Star Birth 4 The Layers of a Neutron Star 6 Superfluid Properties and EOS 10 Magnetic Field Properties and EOS 11 History of Neutron Star Mass and EOS 12 The Known and Unknown Equation of States 15 Nucleon-Nucleon Interactions (NN) and (NNN) 18 Hyperon-Nucleon(HN) and Hyperon-Hyperon (HH) Interactions 22 Equation of State for the Core of a Traditional Neutron Star 22 The Sly and FPS EOS 24 APR and APRb 26 BBB1 and BBB2 28 BGN and Balberg and Gal 31 The Pion Core and Pion Condensation 39 The Kaon Core and Kaon Condensation 40 The Quark Core and Strange Stars 42 Conclusion 45 References 50 3 This thesis explores the topic of maximum mass stability of neutron stars.
    [Show full text]
  • Exploring the Nature of the Universe
    EXPLORING THE NATURE OF THE UNIVERSE CERN explores the fundamental structure of the universe by operating a sophisticated complex of accelerators that collide beams of particles or direct them onto fixed targets. The results of these collisions are recorded by giant detectors and analysed by thousands of scientists at CERN and beyond. CERN’S ACCELERATOR COMPLEX AND THE productive year for CERN. In addition to the completion of EXPERIMENTS THAT IT FEEDS the process leading to the update of the European Strategy for Particle Physics (see p. 47), 2020 saw many remarkable physics results based on the analysis of data taken The Large Hadron Collider (LHC) is CERN’s flagship before the shutdown by both the LHC and the non-LHC machine. It collides proton beams at the highest energies experiments. The results include the first indications that the ever created, and the results of these collisions are recorded Higgs boson interacts with second-generation particles, the by seven experiments – ALICE, ATLAS, CMS, LHCb, LHCf, observation of a new form of matter–antimatter asymmetry MoEDAL and TOTEM – and soon also by FASER, the newest in strange-beauty particles, and the demonstration of a LHC experiment. The year 2020 was the second year of technique to reveal the dynamics of the strong interaction the Laboratory’s ongoing long shutdown, during which between composite particles called hadrons. It was also a the accelerator complex and experiments are undergoing special year because 30 March 2020 marked ten years of intensive maintenance and upgrade work. However, despite the LHC physics programme, which has seen almost 3000 the shutdown and the COVID-19 pandemic, 2020 was a very scientific papers published by the LHC experiments.
    [Show full text]
  • 1. Introduction
    ISSN1330–0016 CODEN FIZBE7 HYPERON AND GLUEBALL ELECTROMAGNETIC PRODUCTION STEPHEN R. COTANCH Department of Physics, North Carolina State University, Raleigh, NC, U.S.A. E-mail: [email protected], Fax: 1 919 515 2471 Received 21 January 1999; Accepted 12 July 1999 An analysis of new kaon electroproduction measurements at Jefferson Lab is pre- sented for both proton and deuteron targets. Calculations based upon quantum hadrodynamics are compared to the experimental longitudinal and transverse sep- arated cross sections for elementary KΛ production. Also confronted by data are model predictions for d(e,e’K+)YN inclusive measurements with YN = Λn, Σ0n and Σ−p. In general, both proton and deuteron target experiments are reasonably well described. Finally, glueball production, possible with the anticipated Jefferson Lab beam energy upgrade, is discussed in conjunction with results from a QCD Hamiltonian calculation for the low-lying gluonia spectrum. PACS numbers: 12.39.Mk, 13.60.Le, 13.60.-r, 13.75.Ev UDC 539.126 Keywords: kaon electroproduction, proton and deuteron targets, longitudinal and trans- verse cross sections, glueball production, low-lying gluonia spectrum 1. Introduction Among the very first experiments [1,2] conducted at Jefferson Lab (JLAB) have been those involving strangeness electroproduction utilizing Hall C. The unprece- dented high count rate for exclusive p(e,e’K+)Λ measurements has permitted ex- tracting the most accurate transverse and longitudinal elementary cross sections to date. Also noteworthy is the first kinematically-complete inclusive measurement of d(e,e’K+)YN for YN = Λn, Σ0n and Σ−p. The focus of this work is a theoretical analysis for both of these experiments highlighting the strengths and weaknesses of current models.
    [Show full text]
  • Hyperon Spectra [Iizuka,Ishii,Kadoh,KH, 0910.1179] Mass Splitting of Baryons With
    Hyperon Spectra [Iizuka,Ishii,Kadoh,KH, 0910.1179] Mass splitting of baryons with Superstring Superstring Mass splitting of baryons with Superstring Superstring Our inputs : 1st March 2011 “New hadron” workshop @ Nishina center Holographic QCD and Hadron Physics Koji Hashimoto (RIKEN Nishina Center) w/ N.Iizuka (CERN), P.Yi (KIAS), T.Sakai (Nagoya) S.Sugimoto (IPMU), T.Hirayama (Kyoto), T.Oka (Tokyo), D.K.Hong (Pusan), H.U.Yee (Trieste), F.L.Lin (Taiwan), T.Morita (Crete), T.Ishii, D.Kadoh, T.Nakatsukasa (RIKEN) What is your goal of hadron physics? Unification Quark / Gluon Lattice QCD AdS/CFT Hadron, Nucleon Nuclear Physics Nucleus Unified picture of QCD String theory + D-branes open string meson baryon D-brane glueball closed string confinement 10-dimensional curved spacetime Superstring Lattice Glueball spectrum Superstring Lattice SU(N) Yang-Mills SU(3) + junk massive, Yang-Mills N Only 2 parameters [Brower,Mathur,Tan (03)] [Morningstar,Peardon (99)] Plan Superstringy Hadron Physics Superstringy Nuclear Physics Couplings, Radii of Nucleon [Sakai,Sugimoto,KH (0806.3122)] Superstring Experiment (0.74 fm)2 (0.875 fm)2 0 – 0.116 fm2 0.54 fm 0.674 fm 2.2 2.79 – 1.3 –1.91 0.73 1.27 7.5 13.2 5.8 4.2 – 6.5 Lattice 4.4 3.7 – 7.5 4.99 2.3 – 2.49 0.20 – 0.06 –1.9 – –2.45 Nucleon Form factor Experiment (empirically known dipole behavior) [Sakai,Sugimoto,KH 0806.3122] Superstring : Nucleon mass vs. Quark mass higher. [Hirayama,Hong,KH, 0906.0402] Superstring : Lattice : Hyperon Spectra [Iizuka,Ishii,Kadoh,KH, 0910.1179] Mass splitting of baryons
    [Show full text]