DOCSLIB.ORG

Λ Baryon Production Measurements with the ALICE Experiment at The

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Λ Baryon Production Measurements with the ALICE Experiment at The + Λc baryon production measurements with the ALICE experiment at the LHC Jaime Norman University of Liverpool Thesis submitted in accordance with the requirements of the University of Liverpool for the degree of Doctor of Philosophy December 2017 Abstract Quantum chromodynamics, the quantum field theory that describes the strong interaction, demonstrates a property known as asymptotic freedom which weakens the strong coupling constant αs at high energies or short distances. The measurement of particles containing heavy quarks, i.e. charm and beauty, in high-energy particle collisions is a stringent test of the theory of quantum chromodynamics in the regime where αs is small. In addition, asymptotic freedom leads to a phase transition of nuclear matter at high temperatures or energy densities to a phase known as the Quark-Gluon Plasma, where quarks and gluons are deconfined, and this state of matter can be studied in relativistic heavy-ion collisions. Particles containing heavy quarks, i.e. charm and beauty, have been proposed as probes of the properties of the Quark Gluon Plasma, where the measure- ment of mesons and baryons can offer insight into the transport properties of the medium and mechanisms related to the formation of hadrons during the transition back to ‘confined’ quark states. Proton-proton and proton- lead collisions offer a crucial benchmark for these measurements, and can also reveal important insights into particle production and interaction mechanisms. The goal of this thesis is to investigate the production of the charmed + baryon Λc in high-energy particle collisions with the ALICE detector at the Large Hadron Collider. The measurements presented will test pre- dictions utilising perturbative (small αs) and non-perturbative (large αs) + methods, will test possible cold-nuclear-matter modifications of the Λc yield in proton-lead collisions, and will set the stage for future measure- ments in lead-lead collisions. The measurements are carried out by recon- + − + structing the hadronic decay channel Λc ! pK π , making selections on its decay topology, extracting the signal via an invariant mass analysis, and finally correcting for its selection and reconstruction efficiency. A multivariate technique (Boosted Decision Trees) has been developed and is utilised in order to improve the signal extraction by optimally com- + bining discriminating variables related to the Λc decay topology. This technique has also been investigated as a possible approach to measuring + the Λc baryon in lead-lead collisions in the future, after the upgrade of the ALICE Inner Tracking System will make this measurement possible. + The transverse momentum dependence of the Λc baryon production cross section has been measured in proton-proton collisions at a centre-of-mass energy of 7 TeV and proton-lead collisions at a centre-of-mass energy per nucleon-nucleon collision of 5:02 TeV, in the transverse momentum range 2 < pT < 12 GeV=c, and is shown to be under-predicted by theoretical + 0 calculations. The baryon-to-meson ratio Λc /D has been measured to be consistent in proton-proton collisions and proton-lead collisions and under-predicted by theoretical calculations. The nuclear modification fac- tor RpPb is measured to be consistent with unity and in agreement with + the D meson RpPb, indicating no significant modification of the Λc yield in proton-lead collisions with respect to proton-proton collisions within the experimental uncertainties. Finally, Boosted Decision Trees have been shown to significantly improve the statistical precision with which the + measurement of the Λc baryon can be made in lead-lead collisions with the ALICE detector in the future. 4 Author's Contribution Throughout my PhD I have been working as part of the ALICE collaboration. + − + The work presented in this thesis extends the Λc ! pK π analysis in pp and p{ + Pb collisions to include a multivariate selection (using Boosted Decision Trees) of Λc candidates. This was carried out extending the framework developed by collaborators, and while I used much of the pre-existing framework all analysis work in this thesis, + including the Λc candidate selection, signal extraction, corrections and systematic uncertainties was performed by me. I also played a large role in the analysis performed in pp and p{Pb collisions using the standard, cut-based method, and developed the + strategy to merge the Λc analyses measured using different decay channels, though this is not presented in detail here. The preliminary results shown in this thesis were presented by myself at the `Strangeness in Quark Matter' conference in 2017 [1]. An extension of this work also involved a study to evaluate the statistical improve- + ment that will be gained from using a multivariate approach to extract the Λc signal in Pb{Pb collisions, after the upgraded ALICE Inner Tracking System is installed. This was carried out as an extension of and comparison to work performed for the Inner Tracking System Technical Design Report, and this work constitutes a chapter of this thesis. In addition to the work presented here, I helped review the analysis of the D meson p production cross section measurements at s = 5 TeV as part of the Analysis Review Committee, which have been presented as preliminary results at conferences. For my service task, I worked on a laser soldering technique that was being explored to bond the silicon chips of the Inner Tracking System upgrade to a circuit-board. I also had the opportunity to give overview talks on open heavy-flavour measurements at ALICE - at the `High pT physics in the RHIC-LHC era' workshop at Brookhaven National Laboratory, and at the `55th International Winter Meeting on Nuclear Physics' in Bormio, Italy [2]. All the work presented in this thesis is the result of my own work, except where explicit reference is made to the work of others. Acknowledgements Firstly, big thanks to my primary supervisor Marielle Chartier. From when I begun my undergraduate project to finishing my PhD, Marielle has supported and encouraged me throughout. Thanks also to my secondary supervisors, John Dainton for patiently talking through many ideas in this work, and Roy Lemmon for his feedback and help in shaping this thesis. Many thanks to Rossella Romita for first introducing me to the ALICE experiment and this analysis, and to Marcel Araujo Silva Figueredo, with whom the analyses in this thesis were finalised. It was a pleasure to work closely with both of you during the first couple of years of my PhD, and I learned a lot from both of you. During my time in ALICE I have been lucky to work in collaboration with many people, with whom I shared many interesting discussions. Thanks to those who I + have worked with directly on the Λc analysis, in particular to Chiara Zampolli and Andrea Alici for their help at the start of this analysis. Thanks to to Davide Caffarri and Zaida Conesa del Valle for the helpful discussions as well as the opportunity to present heavy-flavour results from ALICE at interesting conferences, and thanks to Andre Mischke, Jesus Guillermo Contreras Nuno, Francesco Prino and Martin Voelkl for their help in reviewing the analyses at different stages. Thanks to Andrea Dainese and Cristina Terrevoli for their useful discussions in shaping the studies presented in chapter 6 of this work. I would also like to thank Petra Riedler, Luciano Musa and Antoine Junique for the opportunity to work on the upgrade of the Inner Tracking System for my service task. Liverpool has become a second home over the past seven years. Thanks to ev- eryone I met during my undergraduate degree and my PhD, in particular K¯arlis Dreimanis, John Anders and David Morris for all the jokes and the drinks. Huge thanks to Jonathan Tinsley for proofreading sections of this thesis. Thanks also to all my non-physicist friends for giving me a welcome escape from physics when needed and for pretending to be interested in this work. Thanks to my family; my sister Meryn, and my parents Maggie and Bob - I would not be writing this if it wasn't for my parents consistent encouragement and support. And lastly to the `other' Alice, Alice Colquhoun, for sharing all the stress, the travelling, and enjoyment of the last few years. She has been much more than a 16 × 16 × 26 m3, 10; 000 tonne particle physics experiment to me, and for that I thank her. For Peter Norman, \science is either physics or stamp collecting." Contents List of Figures iii List of Tables vii 1 Introduction 1 1.1 The Standard Model . .2 1.2 Quantum Chromodynamics . .2 1.2.1 Confinement . .4 1.2.2 Deconfinement . .6 1.3 Quark-Gluon Plasma in heavy-ion collisions . 10 1.3.1 Kinematics of the collision . 12 1.3.2 Multiplicities and energy densities . 13 1.3.3 Thermal properties of the Quark-Gluon Plasma . 15 1.3.4 Nuclear modification factor . 16 1.3.5 Baryon-to-Meson Anomaly . 18 1.3.6 Collectivity . 20 1.4 Summary . 24 2 Heavy-flavour production - from pp to heavy-ion collisions 25 2.1 Theoretical description . 26 2.1.1 Heavy-flavour production in pp collisions . 26 2.1.2 Heavy-flavour production in p{Pb collisions . 33 2.1.3 Heavy-flavour production in Pb{Pb collisions . 36 2.2 Experimental Results . 42 2.2.1 Experimental results in pp and p{Pb collisions . 42 2.2.2 Experimental results in Pb{Pb collisions . 47 2.3 Aim of this thesis . 49 i CONTENTS 3 ALICE Experimental Setup 52 3.1 The Large Hadron Collider . 52 3.2 The ALICE detector . 54 3.2.1 The Inner Tracking System . 57 3.2.2 Time Projection Chamber . 59 3.2.3 Time-Of-Flight Detector .
Load more
Loading...
Loading...
Loading...
Loading...
Loading...

196 pages remaining, click to load more.

Recommended publications
  • CERN Courier–Digital Edition
    CERNMarch/April 2021 cerncourier.com COURIERReporting on international high-energy physics WELCOME CERN Courier – digital edition Welcome to the digital edition of the March/April 2021 issue of CERN Courier. Hadron colliders have contributed to a golden era of discovery in high-energy physics, hosting experiments that have enabled physicists to unearth the cornerstones of the Standard Model. This success story began 50 years ago with CERN’s Intersecting Storage Rings (featured on the cover of this issue) and culminated in the Large Hadron Collider (p38) – which has spawned thousands of papers in its first 10 years of operations alone (p47). It also bodes well for a potential future circular collider at CERN operating at a centre-of-mass energy of at least 100 TeV, a feasibility study for which is now in full swing. Even hadron colliders have their limits, however. To explore possible new physics at the highest energy scales, physicists are mounting a series of experiments to search for very weakly interacting “slim” particles that arise from extensions in the Standard Model (p25). Also celebrating a golden anniversary this year is the Institute for Nuclear Research in Moscow (p33), while, elsewhere in this issue: quantum sensors HADRON COLLIDERS target gravitational waves (p10); X-rays go behind the scenes of supernova 50 years of discovery 1987A (p12); a high-performance computing collaboration forms to handle the big-physics data onslaught (p22); Steven Weinberg talks about his latest work (p51); and much more. To sign up to the new-issue alert, please visit: http://comms.iop.org/k/iop/cerncourier To subscribe to the magazine, please visit: https://cerncourier.com/p/about-cern-courier EDITOR: MATTHEW CHALMERS, CERN DIGITAL EDITION CREATED BY IOP PUBLISHING ATLAS spots rare Higgs decay Weinberg on effective field theory Hunting for WISPs CCMarApr21_Cover_v1.indd 1 12/02/2021 09:24 CERNCOURIER www.
    [Show full text]
  • Qcd in Heavy Quark Production and Decay
    QCD IN HEAVY QUARK PRODUCTION AND DECAY Jim Wiss* University of Illinois Urbana, IL 61801 ABSTRACT I discuss how QCD is used to understand the physics of heavy quark production and decay dynamics. My discussion of production dynam- ics primarily concentrates on charm photoproduction data which is compared to perturbative QCD calculations which incorporate frag- mentation effects. We begin our discussion of heavy quark decay by reviewing data on charm and beauty lifetimes. Present data on fully leptonic and semileptonic charm decay is then reviewed. Mea- surements of the hadronic weak current form factors are compared to the nonperturbative QCD-based predictions of Lattice Gauge The- ories. We next discuss polarization phenomena present in charmed baryon decay. Heavy Quark Effective Theory predicts that the daugh- ter baryon will recoil from the charmed parent with nearly 100% left- handed polarization, which is in excellent agreement with present data. We conclude by discussing nonleptonic charm decay which are tradi- tionally analyzed in a factorization framework applicable to two-body and quasi-two-body nonleptonic decays. This discussion emphasizes the important role of final state interactions in influencing both the observed decay width of various two-body final states as well as mod- ifying the interference between Interfering resonance channels which contribute to specific multibody decays. "Supported by DOE Contract DE-FG0201ER40677. © 1996 by Jim Wiss. -251- 1 Introduction the direction of fixed-target experiments. Perhaps they serve as a sort of swan song since the future of fixed-target charm experiments in the United States is A vast amount of important data on heavy quark production and decay exists for very short.
    [Show full text]
  • Slides Lecture 1
    Advanced Topics in Particle Physics Probing the High Energy Frontier at the LHC Ulrich Husemann, Klaus Reygers, Ulrich Uwer University of Heidelberg Winter Semester 2009/2010 CERN = European Laboratory for Partice Physics the world’s largest particle physics laboratory, founded 1954 Historic name: “Conseil Européen pour la Recherche Nucléaire” Lake Geneva Proton-proton2500 employees, collider almost 10000 guest scientists from 85 nations Jura Mountains 8.5 km Accelerator complex Prévessin site (approx. 100 m underground) (France) Meyrin site (Switzerland) Probing the High Energy Frontier at the LHC, U Heidelberg, Winter Semester 09/10, Lecture 1 2 Large Hadron Collider: CMS Experiment: Proton-Proton and Multi Purpose Detector Lead-Lead Collisions LHCb Experiment: B Physics and CP Violation ALICE-Experiment: ATLAS Experiment: Heavy Ion Physics Multi Purpose Detector Probing the High Energy Frontier at the LHC, U Heidelberg, Winter Semester 09/10, Lecture 1 3 The Lecture “Probing the High Energy Frontier at the LHC” Large Hadron Collider (LHC) at CERN: premier address in experimental particle physics for the next 10+ years LHC restart this fall: first beam scheduled for mid-November LHC and Heidelberg Experimental groups from Heidelberg participate in three out of four large LHC experiments (ALICE, ATLAS, LHCb) Theory groups working on LHC physics → Cornerstone of physics research in Heidelberg → Lots of exciting opportunities for young people Probing the High Energy Frontier at the LHC, U Heidelberg, Winter Semester 09/10, Lecture 1 4 Scope
    [Show full text]
  • Proposal for Nuclear Physics Experiment at RI Beam Factory (RIBF NP-PAC-12, 2013)
    User Support Office use only Date: Date: Proposal for Nuclear Physics Experiment at RI Beam Factory (RIBF NP-PAC-12, 2013) Study of density dependence of the symmetry energy with the measurements Title of Experiment of charged pion ratio in heavy RI collisions [ x] NP experiment [ ] Detector R&D [ ] Construction Category [ ] Update proposal (Experimental Program: NP – ) Experimental [ ] GARIS [ ] RIPS [ x] BigRIPS Devices [ ] Zero Degree [ ] SHARAQ [ x] SAMURAI Detectors [ ] DALI2 [ ] GRAPE [ ] EURICA Co-spokesperson : Name William G. Lynch Institution NSCL, Michigan State University Title of position Professor Address 1 Cyclotron, East Lansing, MI 48824-1321, USA Tel +1-517-333-6319 Fax +1-517-353-5967 Email lynch@nscl.msu.edu Co-spokesperson : Name Tetsuya Murakami Institution Department of Physics, Kyoto University Title of position Lecturer Address 29-25 Kitabatake Kohata Uji, Kyoto 611-0002, Japan Tel +81-75-753-3866 Fax +81-75-753-3887 Email murakami@scphys.kyoto-u.ac.jp Your proposal should be sent to User Support Office (UserSupportOffice@ribf.riken.jp) Co-spokesperson : Name Tadaaki Isobe Institution RIKEN, Nishina Center Title of position Research Scientist Address RIBF BLDG318, RIKEN Hirosawa 2-1, Wako, Saitama, Japan Tel +81-48-467-4174 Fax +81-48-462-4464 Email isobe@riken.jp Co-spokesperson : Name Betty Tsang Institution NSCL, Michigan State University Title of position Professor Address 1 Cyclotron, East Lansing, MI 48824-1321, USA Tel +1-517-333-6386 Fax +1-517-353-5967 Email tsang@nscl.msu.edu Beam Time Request Summary: Please indicate requested beam times of TUser–Tuning & TUser–Data Run only. TBigRIPS and Total times will be given by RIKEN.
    [Show full text]
  • Mesures Directes Des Masses De {Sup 100}Sn Et De
    FR9701871 GANIL T 96 06 Universite de Caen THESE presentee par Marielle CHARTIER pour obtenir le GRADE de DOCTEUR EN SCIENCES DE L'UNIVERSITE DE CAEN sujet: Mesures directes des masses de 100Sn et de noyaux exotiques proches de la ligne N — Z soutenue le 31 Octobre 1996 devant le jury suivant : Monsieur G. AUDI Rapporteur Monsieur W. BENENSON Monsieur A. FLEURY Monsieur W. MITTIG Directeur Monsieur A. MUELLER Monsieur E. ROECKL Rapporteur Monsieur B. TAMAIN President GANIL T 96 06 Universite de Caen THESE presentee par Marielle CHARTIER pour obtenir le GRADE de DOCTEUR EN SCIENCES DE L'UNIVERSITE DE CAEN sujet: Me sure s directes des masses de 100 Sn et de noyaux exotiques proches de la ligne N = Z soutenue le 31 Octobre 1996 devant le jury suivant : Monsieur G. AUDI Rapporteur Monsieur W. BENENSON Monsieur A. FLEURY Monsieur W. MITTIG Directeur Monsieur A. MUELLER Monsieur E. ROECKL Rapporteur Monsieur B. TAMAIN President Mesures directes des masses de Sn et de noyaux exotiques proches de la ligne N = Z Remerciements Certaines rencontres, decisives et riches d ’espoir, ont suscite et renforce mon ent- housiasme pour la recherche en physique nucleaire. La premiere personae que j’aimerais remercier est tout naturellement celle sans qui je n ’aurais peut-etre pas choisi cette voie ni pu avoir la chance de venir a Caen. Merci Nimet ! Je tiens egalement a remercier Messieurs Samuel Harar, Daniel Guerreau, Jerome Fouan et Vensemble des physiciens du GANIL pour m’avoir accueillie dans leur labora- toire et per mis d'effectuer ma these dans d ’excellentes conditions, et auxquels j’associe Vensemble du personnel du GANIL pour sa gentillesse et la qualite de ses competences.
    [Show full text]
  • Scientific Opportunities with Fast Fragmentation Beams from RIA
    Scientific Opportunities with Fast Fragmentation Beams from RIA National Superconducting Cyclotron Laboratory Michigan State University March 2000 EXECUTIVE SUMMARY................................................................................................... 1 1. INTRODUCTION............................................................................................................. 5 2. EXTENDED REACH WITH FAST BEAMS .................................................................. 9 3. SCIENTIFIC MOTIVATION......................................................................................... 12 3.1. Properties of Nuclei far from Stability ..................................................................... 12 3.2. Nuclear Astrophysics................................................................................................ 15 4. EXPERIMENTAL PROGRAM...................................................................................... 20 4.1. Limits of Nuclear Existence ..................................................................................... 20 4.2. Extended and Unusual Distributions of Neutron Matter .......................................... 33 4.3. Properties of Bulk Nuclear Matter............................................................................ 39 4.4. Collective Oscillations.............................................................................................. 51 4.5. Evolution of Nuclear Properties Towards the Drip Lines ........................................ 56 Appendix A: Rate
    [Show full text]
  • Highlights from ALICE
    Highlights from ALICE Michael Weber for the ALICE Collaboration Quark Matter, Wuhan, 04-09 Nov 2019 Michael Weber (SMI) Opening the doors (December 2018) CERN-PHOTO-201812-335 2 Quark Matter, Wuhan, 04-09 Nov 2019 Michael Weber (SMI) Soon after CERN-PHOTO-201903-053 Quark Matter, Wuhan, 04-09 Nov 2019 Michael Weber (SMI) 3 Harvest of the past ten years Recorded L System Year(s) √s (TeV) int NN (for muon triggers) 2010,2011 2.76 ~75 μb-1 Pb–Pb 2015 5.02 ~0.25 nb-1 2018 5.02 ~0.55 nb-1 Xe–Xe 2017 5.44 ~0.3 μb-1 2013 5.02 ~15 nb-1 p–Pb 2016 5.02, 8.16 ~3 nb-1; ~25 nb-1 New for QM 2019: ~200 μb-1; ~100 nb-1; 2009-2013 0.9,2.76,7,8 ~1.5 pb-1; ~2.5 pb-1 ● Full 13 TeV pp data set with high-multiplicity triggers pp ● 2018 Pb-Pb with central and semi-central triggers 2015,2017 5.02 ~1.3 pb-1 ● Selected results out of 26 parallel talks, 2015-2018 13 ~36 pb-1 68 posters, and 18 new papers Labels used in this presentation: New since last QM New New preliminary for QM Final On arXiv for QM Quark Matter, Wuhan, 04-09 Nov 2019 Michael Weber (SMI) 4 Outline Initial state → Hadronic structure and photoproduction QGP - Macroscopic properties → Properties of QCD matter and the transition between phases QGP - Microscopic dynamics → Degrees of freedom at each stage and their interactions Small systems → Unified picture of QCD particle production from small to larger systems Hadron physics → LHC as laboratory for hadron interaction studies Following the open questions in the HL-LHC WG5 yellow report Quark Matter, Wuhan, 04-09 Nov 2019 Michael Weber (SMI) 5 ALICE parallel talks Initial state ● Low-mass dielectron measurements in pp, p-Pb and Pb-Pb collisions with ALICE at the LHC S.
    [Show full text]
  • Heavy-Ion Collisions at the Dawn of the Large Hadron Collider Era
    Heavy-Ion Collisions at the Dawn of the Large Hadron Collider Era J. Takahashi Universidade Estadual de Campinas, São Paulo, Brazil Abstract In this paper I present a review of the main topics associated with the study of heavy-ion collisions, intended for students starting or interested in the field. It is impossible to summarize in a few pages the large amount of information that is available today, after a decade of operations of the Relativistic Heavy Ion Collider and the beginning of operations at the Large Hadron Collider. Thus, I had to choose some of the results and theories in order to present the main ideas and goals. All results presented here are from publicly available references, but some of the discussions and opinions are my personal view, where I have made that clear in the text. 1 Introduction In this very exciting field of science, we use particle accelerators to collide heavy ions such as lead or gold nuclei, instead of colliding single protons or electrons. By doing so, we produce a much more violent collision in which a large number of particles are created and a considerable amount of energy is deposited in a volume bigger than the size of a single proton. As a result, a highly excited state of matter is created, and this state can have characteristics different from those of regular hadronic matter. It is postulated that, if the energy density is high enough, the system formed will be in a state where quarks and gluons are no longer confined into hadrons and thus exhibit partonic degrees of freedom [1,2].
    [Show full text]
  • Femtoscopy of Proton-Proton Collisions in the ALICE Experiment
    Femtoscopy of proton-proton collisions in the ALICE experiment DISSERTATION Presented in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the Graduate School of The Ohio State University By Nicolas Bock, B.Sc. B.Eng., M.Sc. Graduate Program in Physics The Ohio State University 2011 Dissertation Committee: Professor Thomas J. Humanic, Advisor Professor Michael Lisa #1 Professor Klaus Honscheid #2 Professor Richard Furnstahl #3 c Copyright by Nicolas Bock 2011 Abstract The Large Ion Collider Experiment (ALICE) at CERN has been designed to study matter at extreme conditions of temperature and pressure, with the long term goal of observing deconfined matter (free quarks and gluons), study its properties and learn more details about the phase diagram of nuclear matter. The ALICE experiment provides excellent particle tracking capabilities in high multiplicity proton-proton and heavy ion collisions, allowing to carry out detailed research of nuclear matter. This dissertation presents the study of the space time structure of the particle emission region, also known as femtoscopy, in proton- proton collisions at 0.9, 2.76 and 7.0 TeV. The emission region can be characterized by taking advantage of the Bose-Einstein effect for identical particles, which causes an enhancement of produced identical pairs at low relative momentum. The geometry of the emission region is related to the relative momentum distribution of all pairs by the Fourier transform of the source function, therefore the measurement of the final relative momentum distribution allows to extract the initial space-time characteristics. Results show that there is a clear dependence of the femtoscopic radii on event multiplicity as well as transverse momentum, a signature of the transition of nuclear matter into its fundamental components and also of strong interaction among these.
    [Show full text]
  • Charmed Bottom Baryon Spectroscopy from Lattice QCD
    W&M ScholarWorks Arts & Sciences Articles Arts and Sciences 2014 Charmed bottom baryon spectroscopy from lattice QCD Zachary S. Brown College of William and Mary Kostas Orginos College of William and Mary William Detmold Stefan Meinel Stefan Meinel Follow this and additional works at: https://scholarworks.wm.edu/aspubs Recommended Citation Brown, Z.S., Detmold, W., Meinel, S., & Orginos, K.N. (2014). Charmed bottom baryon spectroscopy from lattice QCD. This Article is brought to you for free and open access by the Arts and Sciences at W&M ScholarWorks. It has been accepted for inclusion in Arts & Sciences Articles by an authorized administrator of W&M ScholarWorks. For more information, please contact scholarworks@wm.edu. Charmed bottom baryon spectroscopy from lattice QCD Zachary S. Brown,1, 2 William Detmold,3 Stefan Meinel,3, 4, 5 and Kostas Orginos1, 2 1Department of Physics, College of William and Mary, Williamsburg, VA 23187, USA 2Thomas Jefferson National Accelerator Facility, Newport News, VA 23606, USA 3Center for Theoretical Physics, Massachusetts Institute of Technology, Cambridge, MA 02139, USA 4Department of Physics, University of Arizona, Tucson, AZ 85721, USA 5RIKEN BNL Research Center, Brookhaven National Laboratory, Upton, NY 11973, USA We calculate the masses of baryons containing one, two, or three heavy quarks using lattice QCD. We consider all possible combinations of charm and bottom quarks, and compute a total of 36 P 1 + P 3 + different states with J = 2 and J = 2 . We use domain-wall fermions for the up, down, and strange quarks, a relativistic heavy-quark action for the charm quarks, and nonrelativistic QCD for the bottom quarks.
    [Show full text]
  • Magnetic Moment of Charmed Baryon Μλc
    BLEU du CAc 03/03/2017 _______________________________________________________________________________________________ ! I. Préambule général Ce « Bleu du CAc » présente une synthèse (QCM et questionnaire ouvert 1 menée par le Conseil Académique (CAc) auprès de la communauté (personnels MAGNETIC MOMENT OFpermanents , sous contrat et étudiants) sur les orientations (objectifs / structure / organisation) qui devraient prévaloir au sein de la future Université cible « Paris-Saclay ». Cette synthèse est découpée en six items majeurs qui, nt diverses recommandations. Elle constitue donc un socle de propositions solides issues réflexion collective de la communauté des personnels et usagers de Paris- CHARMED BARYON Saclay, sur lequel le « GT des sept » pourrait/devrait cette communauté autour des futures bases de université cible. Emi KOU (LAL) Présentation de : for charm g-2 collaborationenquête réalisée par le CAc du 15 décembre 2016 au 7 février 2017 comportait un questionnaire (informatique) S. Barsuk, O. Fomin, L. Henri, A. Korchin, M. Liul,en deuxE. Niel,parties : P. Robbe, A. Stocchi I. Based on arXiv:1812.#### mble des personnels. pas été partout le cas : le -Saclay la garantie de distribution des messages officiels du Conseil Académique à personnel. II. Une partie ouverte destinée à tout collectif (Conseil de Laboratoire, par exemple). Tau-Charm factory workshop, 3-6 DecemberLa synthèse 2018 présentée at ciLAL-dessous prend en compte ces deux . Analyse des réponses reçues : I. Partie QCM 2135 réponses dont 2021 complètes : 1. Nombre de réponses comparable au nombre des participants aux élections de 2015 au CA et au CAc. 2. ~33% des réponses proviennent des étudiants, avec un taux de participation plus fort pour les étudiants des Grandes Ecoles.
    [Show full text]
  • FERMILAB and Now a Charmed Baryon
    Irwin Gaines presenting the results of the Columbia/Fermilab/Ha waiI Illinois experiment at the Fermilab which has strong evidence for the existence of a charmed baryon at a mass of 2.26 GeV. (Photo Fermilab) selected the target protons with a particular orbital angular momentum. These target protons could then have their spins parallel or antiparallel to the orbital angular momentum and the scattering cross section could be expected to show asymmetries of op­ posite sign depending on whether the scattering took place from a nucleon with spin parallel or antiparallel. Such asymmetries were clearly seen. A very thorough study of the nucleon-nucleon interaction at inter­ mediate energies is being carried out by the BASQUE collaboration (Bed­ ford / AERE Harwell / Surrey / Queen Mary/Universities of B.C. and Victo­ ria). Over a range of energies from 200 to 500 MeV they are measuring all the interaction parameters. Proton- proton data using the polarized proton beam is now being analysed at the Rutherford Laboratory and data col­ lection on polarized neutron-proton scattering is now under way. Some experiments where intensity is at a premium are at the TRIUMF resolution of 1.5 %. The pions can be medical facility where negative pion delivered over an area variable from FERMILAB beams are to be used for radiotherapy. 3 x 3 cm2 to 10 x 10 cm2 or to And now a Known as the Batho Biomedical 4x15 cm2. The excellent quality of Facility (in memory of Harold Batho, the beam has already been exploited charmed baryon the physicist from the British Columbia by a British Columbia team in a Month by month we seem to be chalk­ Cancer Institute who initiated the positive pion elastic scattering experi­ ing up fresh pieces of evidence sup­ development of the facility before he ment on carbon at 29 MeV.
    [Show full text]