DOCSLIB.ORG

Spectroscopy of Neutron–Rich Oxygen and Fluorine Nuclei Via Single–Neutron Knockout Reactions

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Spectroscopy of Neutron–Rich Oxygen and Fluorine Nuclei Via Single–Neutron Knockout Reactions SPECTROSCOPY OF NEUTRON{RICH OXYGEN AND FLUORINE NUCLEI VIA SINGLE{NEUTRON KNOCKOUT REACTIONS by Ben Pietras A THESIS Submitted to the University of Liverpool in partial fulfilment of the requirements for the degree of DOCTOR OF PHILOSOPHY Department of Physics 2009 Contents Acknowledgements xii Abstract xiv 1 Introduction 1 1.1 The Nucleus . 1 1.2 The Magic Numbers and Shell Structure . 3 1.3 The Nuclear Shell Model . 3 1.3.1 The Woods Saxon Potential . 4 1.3.2 The Spin{Orbit Interaction . 5 1.4 Evolution of Shell Structure far from Stability . 8 1.4.1 Nuclear Density Profiles . 8 1.4.2 Halo Nuclei . 9 1.4.3 Evolution of Shell Gaps . 10 1.5 New Magic Numbers at N = 14, 16 . 12 1.5.1 Experimental Evidence . 12 1.5.2 The Tensor Force . 15 ii 1.6 Single{Neutron Removal Reactions . 18 1.6.1 Longitudinal Momentum Distributions . 20 1.6.2 Adiabatic Approximation . 23 1.6.3 Serber Reaction Model . 24 1.6.4 Eikonal Theory . 26 2 Experimental Method 33 2.1 Radioactive Ion Beam Production . 33 2.1.1 Primary Beam Production . 34 2.1.2 Projectile Fragmentation . 35 2.1.3 Fragment Separation . 35 2.2 Experimental Detection Setup . 37 2.2.1 Overview of Experimental Setup . 37 2.2.2 The SPEG Spectrometer . 39 2.3 Direct Beam and Fragment Identification . 44 2.3.1 Identification Gates . 46 2.3.2 The Hybrid γ{ray Array . 49 2.3.3 EXOGAM . 50 2.3.4 The NaI Array . 53 2.4 γ{ray Array Calibration . 54 2.4.1 EXOGAM . 54 2.4.2 NaI Array . 57 2.5 SPEG Calibrations . 58 iii 2.6 Drift Chambers . 64 2.7 Ionisation Chamber . 67 2.8 Data Acquisition Trigger . 71 3 Analysis 76 3.1 Target Thickness . 76 3.2 Doppler Shift and Broadening Correction . 77 3.2.1 Lorentz factor calculation . 77 3.2.2 Theta Calculation . 79 3.3 Inclusive Cross Sections . 82 3.4 Exclusive Cross Sections . 87 3.5 Inclusive Momentum Distributions . 91 3.6 Exclusive Momentum Distributions . 92 3.7 Eikonal Calculations . 95 3.7.1 Exclusive Cross Sections . 95 3.7.2 Experimental Spectroscopic factors . 99 3.7.3 Exclusive Momentum Distributions . 99 3.7.3.1 Transformation of Theoretical LMDs . 101 3.7.3.2 Convolution of Theoretical LMDs . 101 3.7.4 Interactions and Model Spaces . 104 4 Results and Discussion 106 4.1 Inclusive One-Neutron Removal Cross Sections . 107 4.2 23O!22O ................................. 108 iv 4.2.1 Discussion . 108 4.2.2 Inclusive One-Neutron Removal Cross Sections . 109 4.2.3 Longitudinal Momentum Distributions . 113 4.3 24F!23F.................................. 115 4.3.1 Discussion . 115 4.3.2 γγ Coincidences . 117 4.3.3 Exclusive One{Neutron Removal Cross Sections and Spectroscopic Factors . 125 4.3.4 Longitudinal Momentum Distributions . 127 4.4 25F!24F.................................. 133 4.4.1 Discussion . 133 4.4.2 Exclusive One-Neutron Removal Cross Sections . 137 4.4.3 Longitudinal Momentum Distributions . 137 4.4.4 Experimental Spectroscopic Factors . 142 4.5 26F!25F.................................. 144 4.5.1 Discussion . 144 4.5.2 Longitudinal Momentum Distributions . 148 Summary 150 References 152 v List of Figures 1.1 The Chart of Nuclides . 2 1.2 The Nuclear Shell Model . 7 1.3 Hartree{Fock calculated neutron and proton density profiles. 8 1.4 Evolution of Shell Gaps. 11 1.5 The effect of Isospin on the Neutron Separation Energy. 13 + 1.6 Evolution of 21 energy in light even{even nuclei. 14 1.7 Neutron effective single particle energies. 15 1.8 Schematics illustrating the tensor interaction. 16 1.9 Neutron effective single{particle energies for 30Si and 24O. 17 1.10 Single{nucleon removal reaction schematic. 19 1.11 Core Fragment Inclusive Longitudinal Momentum Distributions. 21 1.12 Core fragment 25Ne LMD . 22 1.13 Three{body system. 23 1.14 Serber model. 24 1.15 Effect of valence neutron's angular momentum orientation on cross section. 25 vi 1.16 28Mg core fragment Theoretical Longitudinal Momentum Distributions. 26 1.17 One{dimensional Eikonal case. 28 1.18 Nucleon travelling through finite range potential of the target. 28 1.19 Core and valence neutron S{matrices for 26F projectile. 30 2.1 General layout of GANIL, indicating the location of SISSI. 36 2.2 Experimental setup, from secondary beam production to SPEG. 38 2.3 SPEG High{Resolution Mass Spectrometer. 39 2.4 Optics of SPEG. 44 2.5 ∆E vs. E for all ions. 46 2.6 ∆E vs. E for the Fluorine and Oxygen isotopes. 47 2.7 Xf vs. TOF for the Fluorine and Oxygen isotopes. 47 2.8 ∆E vs. Xf for the Fluorine and Oxygen isotopes. 48 2.9 Hybrid γ{ray Array. 49 2.10 One EXOGAM Clover, comprising four segmented coaxial detectors. 50 2.11 Simulated Energy Resolution for EXOGAM. 52 2.12 Schematic of Sodium Iodide detectors. 53 2.13 EXOGAM energy Calibration. 55 2.14 Efficiency vs. Energy for the entire EXOGAM array. 56 2.15 NaI fitting technique for 60Co. 57 2.16 Energy vs Efficiency for the total NaI array. 58 2.17 SPEG focal plane schematic. 59 2.18 Calibration Mask. 61 vii 2.19 Bρref scan with mask. 62 2.20 Bρ scan across SPEG focal plane. 63 2.21 Dispersion calibration. 64 2.22 SPEG Drift Chambers. 66 2.23 Drift chamber TDC calibration. 67 2.24 Ionisation chamber TOF correction. 68 2.25 Ionisation gas pressure correction. 70 2.26 Gas pressure correction effect. 71 2.27 Circuit Diagram of Germanium link to GMT. 73 2.28 Representation of the timing signals used. 74 2.29 Circuit diagram of the Ganil Master Trigger. 75 3.1 The effect of energy loss through half the 12C target. 79 3.2 EXOGAM clover face. 80 3.3 Example of Doppler{correction and Add-back effects. 82 3.4 Incident beam rate, Fluorine. 83 3.5 Incident Beam Rate Scaled Down to Reaction Fragment Rate. 84 3.6 24F Scaledown factors from LDCX1. 85 3.7 24F Scaledown factors from Trifoil. 86 3.8 Forward EXOGAM Array Ratio. 88 3.9 Backward EXOGAM Array Ratio. 88 3.10 Isotropic Forward EXOGAM Array Efficiency. 89 3.11 Isotropic Backward EXOGAM Array Efficiency. 89 viii 3.12 Background Subtraction schematic. 93 3.13 Example of LMD background subtraction. 94 3.14 Dependence of σsp on RMS radius. 97 3.15 Contributions of stripping (nucleon absorbed) and diffraction (nucleon dissociated) mechanisms to the single{particle cross section. 98 3.16 Eikonal distribution for the 24F fragment. 100 3.17 Transformation from centre{of{mass frame to laboratory frame. 102 3.18 Direct{beam{through{target longitudinal momentum distributions. 103 3.19 Convolution of Fragment Theoretical LMDs with the Projectile DBTT LMD. 104 4.1 Level scheme of 22O. 110 4.2 22O γ spectra. 111 4.3 22O Inclusive LMD from this experiment. 114 4.4 22O Inc. LMD taken from [35]. 114 4.5 Comparison of 22O and 23F state energies. 115 4.6 23F γ spectra. 116 4.7 EXOGAM γγ coincidences for 23F..
Load more

Recommended publications
  • 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 [email protected] 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 [email protected] Your proposal should be sent to User Support Office ([email protected]) 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 [email protected] 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 [email protected] 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]
  • Exotic Nuclei Studied in Light-Ion Induced Reactions at the NESR Storage Ring)
    LOI Identification Nº FAIR- PAC: make cross where applicable APPA [ * ] NUSTAR [ x ] QCD [ * ] Date: 21/01/2005 Technical Proposal for the Design, Construction, Commissioning and Operation of the EXL Project (Exotic nuclei studied in light-ion induced reactions at the NESR storage ring) The EXL Collaboration Abstract: We propose to study the structure of exotic nuclei in light-ion scattering experiments at intermediate energies. The EXL objective is to capitalise on light-ion reactions in inverse kinematics by using novel storage-ring techniques and a universal detector system providing high resolution and large solid angle coverage in kinematically complete measurements. The apparatus shown in Figure 1 is foreseen being installed at the internal target at the NESR storage-cooler ring of the international Facility for Antiproton and Ion Research (FAIR). It comprises (i) a silicon target-recoil detector for charged particles, completed by γ-ray and slow- neutron detectors, located around the internal gas-jet target, (ii) forward detectors for fast ejectiles (both charged particles and neutrons) and (iii) an in-ring heavy-ion spectrometer. The present technical proposal focuses on these detection systems and provides a status report on the conceptual design studies. Synergies with other projects (in particular R3B) have been identified and incorporated in the structure of the collaboration. Spokesperson: Marielle Chartier, [email protected], +44 (0)151 794 6775 Deputy: Jürg Jourdan, [email protected], +41 (0)61 267 3689 Contact person @ GSI: Peter Egelhof, [email protected], +49 (0)6159 71 2662 Heavy-Ion Spectrometer Recoil Detector Neutrons / Charged Ejectiles Recoil Detector Gas jet Beam in Storage Ring Figure 1: Schematic view of the EXL detection systems.
    [Show full text]
  • Measurement of the J/ Elliptic Flow in Pb-Pb Collisions at Snn=5.02Tev
    Measurement of the J/ elliptic flow in Pb-Pb collisions p at sNN=5.02TeV with the muon spectrometer of ALICE at the LHC Audrey Francisco To cite this version: p Audrey Francisco. Measurement of the J/ elliptic flow in Pb-Pb collisions at sNN=5.02TeV with the muon spectrometer of ALICE at the LHC. High Energy Physics - Experiment [hep-ex]. Ecole nationale supérieure Mines-Télécom Atlantique, 2018. English. NNT : 2018IMTA0087. tel-02010296 HAL Id: tel-02010296 https://tel.archives-ouvertes.fr/tel-02010296 Submitted on 7 Feb 2019 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. THESE DE DOCTORAT DE L’ÉCOLE NATIONALE SUPERIEURE MINES-TELECOM ATLANTIQUE BRETAGNE PAYS DE LA LOIRE - IMT ATLANTIQUE COMUE UNIVERSITE BRETAGNE LOIRE ECOLE DOCTORALE N° 596 Matière, Molécules, Matériaux Spécialité : Physique Subatomique et Instrumentation Nucléaire Par Audrey FRANCISCO Measurement of the J/� elliptic flow in Pb-Pb collisions at √sNN=5.02TeV with the muon spectrometer of ALICE at the LHC Thèse présentée et soutenue à Nantes le 24 Septembre 2018 Unité de recherche : SUBATECH— UMR6457 Thèse N° : 2018IMTA0087 Composition du Jury : Président : Pol-Bernard GOSSIAUX Professeur, IMT-Atlantique Examinateurs : Javier CASTILLO CASTELLANOS Chercheur-Ingénieur, CEA Manuel CALDERON DE LA BARÇA SANCHEZ Professeur, University of California Davis Marielle CHARTIER Professeur, University of Liverpool Silvia NICCOLAI Directeur de Recherche CNRS, Univ.
    [Show full text]
  • Design and Construction of the Spirit Tpc
    DESIGN AND CONSTRUCTION OF THE SPIRIT TPC By Suwat Tangwancharoen A DISSERTATION Submitted to Michigan State University in partial fulfillment of the requirements for the degree of Physics-Doctor of Philosophy 2016 ABSTRACT DESIGN AND CONSTRUCTION OF THE SPIRIT TPC By Suwat Tangwancharoen The nuclear symmetry energy, the density dependent term of the nuclear equation of state (EOS), governs important properties of neutron stars and dense nuclear matter. At present, it is largely unconstrained in the supra-saturation density region. This dissertation concerns the design and construction of the SπRIT Time Projection Chamber (SπRIT TPC) at Michigan State University as part of an international collaborations to constrain the symmetry energy at supra-saturation density. The SπRIT TPC has been constructed during the dissertation and transported to Radioactive Isotope Beam Factory (RIBF) at RIKEN, Japan where it will be used in conjunction with the SAMURAI Spectrometer. The detector will measure yield ratios for pions and other light charged particles produced in central collisions of neutron-rich heavy ions such as 132Sn + 124Sn. The dissertation describes the design and solutions to the problem presented by the measurement. This also compares some of the initial fast measurement of the TPC to calculation of the performance characteristics. ACKNOWLEDGMENTS The design and construction of the SAMURAI Pion-Reconstruction and Ion Tracker Time Projection Chamber (SπRIT TPC) involved an international collaboration to study and constrain the symmetry energy term in the nuclear equation of state (EOS) at twice supra- saturation density. The TPC design and construction as well as many additional aspects of the project were supported financially by the U.S.
    [Show full text]
  • November 27, 2012 Dear Members of The
    November 27, 2012 Dear Members of the NSAC Subcommittee on the Implementation of the Long Range Plan: We the undersigned 824 members of the FRIB Users Organization are writing to express the importance of the timely completion of the FRIB project. FRIB is a central component of our future research plans and will enable forefront research and discovery into the nature of atomic nuclei, the origin of elements in WKHFRVPRVWHVWVRIQDWXUH¶VIXQGDPHQWDOODZVDQGVRFLHWDO applications of isotopes. The exciting science case for FRIB and the other rationale for its completion are summarized in the document "FRIB: Opening New Frontiers in Nuclear Science" that we submitted to you in September. The field of nuclear science now encompasses a broad and exciting scientific landscape. Within this landscape, the study of nuclei remains a vital component of the field. Major discoveries are on the horizon into the interactions that govern the properties of nuclei and in the understanding of nuclear processes that drive astrophysical environments. It is likely that other unexpected discoveries will accompany the vast new view of nuclear systems with extreme neutron-to-proton ratios made available by the next generation of rare isotope facilities. The 2007 Long Range Plan outlined the steps needed to achieve a vibrant future for nuclear physics in the U.S. The plan envisions a program where QCD phenomena, nuclei, and fundamental symmetries are studied. It also describes the set of capabilities required to achieve this vision. Specifically, the LRP recognized that a new capability, FRIB, was needed in the area of nuclear structure and nuclear DVWURSK\VLFVDQGFDOOHGWKLVQHHG³PRVWDFXWH´)5,%LVWKH second priority of the 2007 Long Range Plan (the first for new construction) and the first recommendation of the 2012 National Research Council study of Nuclear Physics.
    [Show full text]
  • 29-45 C E N B G F Centre D'études Nucléaires De Bordeaux-Gradignan Le Haut-Vigneau B.P.120 3175 Gradignan Cedex : +33 (0)556 891 800 ^*To) 556 751 180 'Wwwcenbg
    FR9810143 RAPPORT D'ACTIVITÉ 1995-1996 29-45 C E N B G f Centre d'Études Nucléaires de Bordeaux-Gradignan Le Haut-Vigneau B.P.120 3175 Gradignan Cedex : +33 (0)556 891 800 ^*tO) 556 751 180 'wwwcenbg. in2p3.fr CENBG Rapport d'Activité 1995-1996 S* - NEXT PAQE(S) '«f t BLANK avé avec /es /ogtcteû (tfct&n&éte rïovd , e£aÇ£/GÔG et "7/im/ Àottr ~^ùt</o<ixi. t&a mue e,n Àaae. a é/é fucAae/©C ztPrawAoff*a<uùfâi c/e S fta-rie-Q f(a<f*s/eine C&t/éanavd et concerne tes rr/t/tS&i c&ni/ej 1335 e£ 193&, 1397 ' WORD ET WINDOWS SONT DES MARQUES DÉPOSÉES DE MICROSOFT INTERNATIONAL. SCIENTIFIC WORD EST UNE MARQUE DÉPOSÉE DE TCI SOFTWARE RESEARCH. NEXT PAGE(S) left BLANK Avant-Propos Avant-Propos Le Centre d'Études Nucléaires de Bordeaux Gradignan affiche dans son sigle deux idées de base. Il s'agit d'abord d'affirmer que le Centre est un laboratoire de recherche fondamentale, dans le domaine de la physique. Le mot nucléaire est toujours porteur de divers fantasmes et de certaines réalités. Cette affirmation de laboratoire nucléaire nous expose déjà aux regards et est une prise de position forte et voulue. Le CENBG s'affirme ensuite laboratoire de Bordeaux Gradignan. C'est bien sûr une indication géographique nécessaire pour localiser le laboratoire. Cette mention de lieu souligne une forte volonté politique d'intégration dans une région, et confirme que le laboratoire entend être présent et irriguer une région qui aussi le nourrit.
    [Show full text]
  • Proton-Proton Collisions at the Large Hadron Collider's ALICE Experiment: Diffraction and High Multiplicity
    Proton-proton Collisions at the Large Hadron Collider's ALICE Experiment: Diffraction and High Multiplicity Zoe Louise Matthews Thesis submitted for the degree of Doctor of Philosophy Particle Physics Group, School of Physics and Astronomy, University of Birmingham. November 20, 2011 Abstract Diffraction in pp collisions contributes approximately 30 % of the inelastic cross section. Its influ- ence on the pseudorapidity density is not well constrained at high energy. A method to estimate the contributing fractions of diffractive events to the inelastic cross section has been developed, and the fractions are measured in the ALICE detector at 900 GeV (7 TeV) to be fD=0.278±0.055 (fD=0.28±0.054) respectively. These results are compatible with recent ATLAS and ALICE mea- surements. Bjorken's energy density relation suggests that, in high multiplicity pp collisions at the LHC, an environment comparable to A-A collisions at RHIC could be produced. Such events are of great interest to the ALICE Collaboration. Constraints on the running conditions have been established for obtaining a high multiplicity pp data sample using the ALICE detector's multi- plicity trigger. A model independent method to separate a multiplicity distribution from `pile-up' contributions has been developed, and used in connection with other findings to establish a suitable threshold for a multiplicity trigger. It has been demonstrated data obtained under these conditions for 3 months can be used to conduct early strangeness analyses with multiplicities of over 5 times the mean. These findings have resulted in over 16 million high multiplicity events being obtained to date.
    [Show 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.
    [Show full text]
  • Technical Proposal for the Design, Construction, Commissioning and Operation of the EXL Project (Exotic Nuclei Studied in Light
    LOI Identification Nº FAIR- PAC: make cross where applicable APPA [ * ] NUSTAR [ x ] QCD [ * ] Date: 21/01/2005 Technical Proposal for the Design, Construction, Commissioning and Operation of the EXL Project (Exotic nuclei studied in light-ion induced reactions at the NESR storage ring) The EXL Collaboration Abstract: We propose to study the structure of exotic nuclei in light-ion scattering experiments at intermediate energies. The EXL objective is to capitalise on light-ion reactions in inverse kinematics by using novel storage-ring techniques and a universal detector system providing high resolution and large solid angle coverage in kinematically complete measurements. The apparatus shown in Figure 1 is foreseen being installed at the internal target at the NESR storage-cooler ring of the international Facility for Antiproton and Ion Research (FAIR). It comprises (i) a silicon target-recoil detector for charged particles, completed by γ-ray and slow- neutron detectors, located around the internal gas-jet target, (ii) forward detectors for fast ejectiles (both charged particles and neutrons) and (iii) an in-ring heavy-ion spectrometer. The present technical proposal focuses on these detection systems and provides a status report on the conceptual design studies. Synergies with other projects (in particular R3B) have been identified and incorporated in the structure of the collaboration. Spokesperson: Marielle Chartier, [email protected], +44 (0)151 794 6775 Deputy: Jürg Jourdan, [email protected], +41 (0)61 267 3689 Contact person @ GSI: Peter Egelhof, [email protected], +49 (0)6159 71 2662 Heavy-Ion Spectrometer Recoil Detector Neutrons / Charged Ejectiles Recoil Detector Gas jet Beam in Storage Ring Figure 1: Schematic view of the EXL detection systems.
    [Show full text]
  • Étude Des Corrélations Dans La Dissociation De L'8he
    Étude des corrélations dans la dissociation de l’8He B. Laurent To cite this version: B. Laurent. Étude des corrélations dans la dissociation de l’8He. Physique Nucléaire Théorique [nucl-th]. Université de Caen, 2007. Français. tel-00265845 HAL Id: tel-00265845 https://tel.archives-ouvertes.fr/tel-00265845 Submitted on 20 Mar 2008 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. UNIVERSITÉ de CAEN/BASSE-NORMANDIE U.F.R. des SCIENCES ÉCOLE DOCTORALE SIMEM THÈSE présentée par Monsieur Benoit LAURENT et soutenue le 26 Novembre 2007 en vue de l’obtention du DOCTORAT de l’UNIVERSITÉ de CAEN Spécialité : Constituants Élémentaires (Arrêté du 7 août 2006) Titre : Étude des corrélations dans la dissociation de l’8He. JURY Monsieur Jean-Antoine SCARPACI, Directeur de recherche CNRS, IPN Orsay (Rapporteur) Monsieur Jean-Luc SIDA, Ingénieur de recherche, CEA/DAM Bruyères-le-châtel (Rapporteur) Madame Marielle CHARTIER, Maitre de conférence, Université de Liverpool Monsieur Jean-François LECOLLEY, Professeur émérite, Université de Caen Monsieur Nigel ORR, Directeur de recherche CNRS, LPC Caen (Directeur de thèse) La phrase la plus excitante à entendre en science, celle qui annonce de nouvelles découvertes, n’est pas «Eurêka», mais plutôt «Tiens, c’est marrant...» Isaac Asimov Remerciements Premières pages de ce document mais bien souvent dernières pages écrites, ces remerciements marquent la fin d’une belle aventure.
    [Show full text]