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Detmold W, Illa M, Murphy DJ, Oare P, Orginos K, Shanahan PE, Wagman ML, Winter F. Lattice QCD Constraints on the Parton Distribution Functions of ^{3}He. PHYSICAL REVIEW LETTERS 2021; 126:202001. [PMID: 34110196 DOI: 10.1103/physrevlett.126.202001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Accepted: 04/19/2021] [Indexed: 06/12/2023]
Abstract
The fraction of the longitudinal momentum of ^{3}He that is carried by the isovector combination of u and d quarks is determined using lattice QCD for the first time. The ratio of this combination to that in the constituent nucleons is found to be consistent with unity at the few-percent level from calculations with quark masses corresponding to m_{π}∼800 MeV. With a naive extrapolation to the physical quark masses, this constraint is consistent with, and more precise than, determinations from global nuclear parton distribution function fits through the nnnpdf framework. It is thus concretely demonstrated that lattice QCD calculations of light nuclei have imminent potential to enable more precise determinations of the u and d parton distributions in light nuclei and to reveal the QCD origins of the EMC effect.
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Affiliation(s)
- William Detmold
- Center for Theoretical Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Marc Illa
- Departament de Física Quàntica i Astrofísica and Institut de Ciències del Cosmos, Universitat de Barcelona, Martí i Franquès 1, 08028 Barcelona, Spain
| | - David J Murphy
- Center for Theoretical Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Patrick Oare
- Center for Theoretical Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Kostas Orginos
- Department of Physics, College of William and Mary, Williamsburg, Virginia 23187-8795, USA
- Jefferson Laboratory, 12000 Jefferson Avenue, Newport News, Virginia 23606, USA
| | - Phiala E Shanahan
- Center for Theoretical Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Michael L Wagman
- Fermi National Accelerator Laboratory, Batavia, Illinois 60510, USA
| | - Frank Winter
- Jefferson Laboratory, 12000 Jefferson Avenue, Newport News, Virginia 23606, USA
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König S. Few-Body Bound States and Resonances in Finite Volume. FEW-BODY SYSTEMS 2020; 61:20. [PMID: 32684657 PMCID: PMC7357817 DOI: 10.1007/s00601-020-01550-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Accepted: 05/04/2020] [Indexed: 06/11/2023]
Abstract
Since the pioneering work of Lüscher in the 1980s it is well known that considering quantum systems in finite volume, specifically, finite periodic boxes, can be used as a powerful computational tool to extract physical observables. While this formalism has been worked out in great detail in the two-body sector, much effort is currently being invested into deriving analogous relations for systems with more constituents. This work is relevant not only for nuclear physics, where lattice methods are now able to calculate few- and many-nucleon states, but also for other fields such as simulations of cold atoms. This article discusses recent progress regarding the extraction of few-body bound-state and resonance properties from finite-volume calculations of systems with an arbitrary number of constituents.
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Affiliation(s)
- Sebastian König
- Department of Physics, Technische Universität Darmstadt, 64289 Darmstadt, Germany
- ExtreMe Matter Institute EMMI, GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany
- Department of Physics, North Carolina State University, Raleigh, NC 27695 USA
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Abstract
Explorations of the properties of light nuclear systems beyond their lowestlying spectra have begun with Lattice Quantum Chromodynamics. While progress has been made in the past year in pursuing calculations with physical quark masses, studies of the simplest nuclear matrix elements and nuclear reactions at heavier quark masses have been conducted, and several interesting results have been obtained. A community effort has been devoted to investigate the impact of such Quantum Chromodynamics input on the nuclear many-body calculations. Systems involving hyperons and their interactions have been the focus of intense investigations in the field, with new results and deeper insights emerging. While the validity of some of the previous multi-nucleon studies has been questioned during the past year, controversy remains as whether such concerns are relevant to a given result. In an effort to summarize the newest developments in the field, this talk will touch on most of these topics.
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Parreño A, Savage MJ, Tiburzi BC, Wilhelm J, Chang E, Detmold W, Orginos K. Baryon magnetic moments: Symmetries and relations. EPJ WEB OF CONFERENCES 2018. [DOI: 10.1051/epjconf/201817506001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Magnetic moments of the octet baryons are computed using lattice QCD in background magnetic fields, including the first treatment of the magnetically coupled ∑0- ⋀ system. Although the computations are performed for relatively large values of the up and down quark masses, we gain new insight into the symmetries and relations between magnetic moments by working at a three-flavor mass-symmetric point. While the spinflavor symmetry in the large Nc limit of QCD is shared by the naïve constituent quark model, we find instances where quark model predictions are considerably favored over those emerging in the large Nc limit. We suggest further calculations that would shed light on the curious patterns of baryon magnetic moments.
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Aoki S, Doi T, Iritani T. Sanity check for NN bound states in lattice QCD with Lüscher’s finite volume formula – Disclosing Symptoms of Fake Plateaux –. EPJ WEB OF CONFERENCES 2018. [DOI: 10.1051/epjconf/201817505006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The sanity check is to rule out certain classes of obviously false results, not to catch every possible error. After reviewing such a sanity check for NN bound states with the Lüscher’s finite volume formula [1–3], we give further evidences for the operator dependence of plateaux, a symptom of the fake plateau problem, against the claim [4]. We then present our critical comments on [5] by NPLQCD: (i) Operator dependences of plateaux in NPL2013 [6, 7] exist with the P value of 4–5%. (ii) The volume independence of plateaux in NPL2013 does not prove their correctness. (iii) Effective range expansions (EREs) in NPL2013 violate the physical pole condition. (iv) Their comment is partly based on new data and analysis different from the original ones. (v) Their new ERE does not satisfy the Lüscher’s finite volume formula.
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Savage MJ, Shanahan PE, Tiburzi BC, Wagman ML, Winter F, Beane SR, Chang E, Davoudi Z, Detmold W, Orginos K. Proton-Proton Fusion and Tritium β Decay from Lattice Quantum Chromodynamics. PHYSICAL REVIEW LETTERS 2017; 119:062002. [PMID: 28949612 DOI: 10.1103/physrevlett.119.062002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Indexed: 06/07/2023]
Abstract
The nuclear matrix element determining the pp→de^{+}ν fusion cross section and the Gamow-Teller matrix element contributing to tritium β decay are calculated with lattice quantum chromodynamics for the first time. Using a new implementation of the background field method, these quantities are calculated at the SU(3) flavor-symmetric value of the quark masses, corresponding to a pion mass of m_{π}∼806 MeV. The Gamow-Teller matrix element in tritium is found to be 0.979(03)(10) at these quark masses, which is within 2σ of the experimental value. Assuming that the short-distance correlated two-nucleon contributions to the matrix element (meson-exchange currents) depend only mildly on the quark masses, as seen for the analogous magnetic interactions, the calculated pp→de^{+}ν transition matrix element leads to a fusion cross section at the physical quark masses that is consistent with its currently accepted value. Moreover, the leading two-nucleon axial counterterm of pionless effective field theory is determined to be L_{1,A}=3.9(0.2)(1.0)(0.4)(0.9) fm^{3} at a renormalization scale set by the physical pion mass, also agreeing within the accepted phenomenological range. This work concretely demonstrates that weak transition amplitudes in few-nucleon systems can be studied directly from the fundamental quark and gluon degrees of freedom and opens the way for subsequent investigations of many important quantities in nuclear physics.
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Affiliation(s)
- Martin J Savage
- Institute for Nuclear Theory, University of Washington, Seattle, Washington 98195-1550, USA
- Kavli Institute for Theoretical Physics, University of California, Santa Barbara, California 93106, USA
| | - Phiala E Shanahan
- Kavli Institute for Theoretical Physics, University of California, Santa Barbara, California 93106, USA
- Center for Theoretical Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Brian C Tiburzi
- Kavli Institute for Theoretical Physics, University of California, Santa Barbara, California 93106, USA
- Department of Physics, The City College of New York, New York, New York 10031, USA
- Graduate School and University Center, The City University of New York, New York, New York 10016, USA
- RIKEN BNL Research Center, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - Michael L Wagman
- Kavli Institute for Theoretical Physics, University of California, Santa Barbara, California 93106, USA
- Department of Physics, University of Washington, Box 351560, Seattle, Washington 98195, USA
| | - Frank Winter
- Jefferson Laboratory, 12000 Jefferson Avenue, Newport News, Virginia 23606, USA
| | - Silas R Beane
- Kavli Institute for Theoretical Physics, University of California, Santa Barbara, California 93106, USA
- Department of Physics, University of Washington, Box 351560, Seattle, Washington 98195, USA
| | - Emmanuel Chang
- Institute for Nuclear Theory, University of Washington, Seattle, Washington 98195-1550, USA
| | - Zohreh Davoudi
- Kavli Institute for Theoretical Physics, University of California, Santa Barbara, California 93106, USA
- Center for Theoretical Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - William Detmold
- Kavli Institute for Theoretical Physics, University of California, Santa Barbara, California 93106, USA
- Center for Theoretical Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Kostas Orginos
- Jefferson Laboratory, 12000 Jefferson Avenue, Newport News, Virginia 23606, USA
- Department of Physics, College of William and Mary, Williamsburg, Virginia 23187-8795, USA
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Howell C, Tornow W, Witała H. Few-Nucleon Research at TUNL: Probing Two- and Three-Nucleon Interactions with Neutrons. EPJ WEB OF CONFERENCES 2016. [DOI: 10.1051/epjconf/201611304008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Detmold W, Orginos K, Parreño A, Savage MJ, Tiburzi BC, Beane SR, Chang E. Unitary Limit of Two-Nucleon Interactions in Strong Magnetic Fields. PHYSICAL REVIEW LETTERS 2016; 116:112301. [PMID: 27035294 DOI: 10.1103/physrevlett.116.112301] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Indexed: 06/05/2023]
Abstract
Two-nucleon systems are shown to exhibit large scattering lengths in strong magnetic fields at unphysical quark masses, and the trends toward the physical values indicate that such features may exist in nature. Lattice QCD calculations of the energies of one and two nucleons systems are performed at pion masses of m_{π}∼450 and 806 MeV in uniform, time-independent magnetic fields of strength |B|∼10^{19}-10^{20} G to determine the response of these hadronic systems to large magnetic fields. Fields of this strength may exist inside magnetars and in peripheral relativistic heavy ion collisions, and the unitary behavior at large scattering lengths may have important consequences for these systems.
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Affiliation(s)
- William Detmold
- Center for Theoretical Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Kostas Orginos
- Department of Physics, College of William and Mary, Williamsburg, Virginia 23187-8795, USA
- Jefferson Laboratory, 12000 Jefferson Avenue, Newport News, Virginia 23606, USA
| | - Assumpta Parreño
- Department d'Estructura i Constituents de la Matèria. Institut de Ciències del Cosmos (ICC), Universitat de Barcelona, Martí Franquès 1 E08028, Spain
| | - Martin J Savage
- Institute for Nuclear Theory, University of Washington, Seattle, Washington 98195-1550, USA
| | - Brian C Tiburzi
- Department of Physics, The City College of New York, New York, New York 10031, USA
- Graduate School and University Center, The City University of New York, New York, New York 10016, USA
- RIKEN BNL Research Center, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - Silas R Beane
- Department of Physics, University of Washington, Box 351560, Seattle, Washington 98195, USA
| | - Emmanuel Chang
- Institute for Nuclear Theory, University of Washington, Seattle, Washington 98195-1550, USA
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Beane SR, Chang E, Detmold W, Orginos K, Parreño A, Savage MJ, Tiburzi BC. Ab initio Calculation of the np→dγ Radiative Capture Process. PHYSICAL REVIEW LETTERS 2015; 115:132001. [PMID: 26451545 DOI: 10.1103/physrevlett.115.132001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Indexed: 06/05/2023]
Abstract
Lattice QCD calculations of two-nucleon systems are used to isolate the short-distance two-body electromagnetic contributions to the radiative capture process np→dγ, and the photo-disintegration processes γ^{(*)}d→np. In nuclear potential models, such contributions are described by phenomenological meson-exchange currents, while in the present work, they are determined directly from the quark and gluon interactions of QCD. Calculations of neutron-proton energy levels in multiple background magnetic fields are performed at two values of the quark masses, corresponding to pion masses of m_{π}~450 and 806 MeV, and are combined with pionless nuclear effective field theory to determine the amplitudes for these low-energy inelastic processes. At m_{π}~806 MeV, using only lattice QCD inputs, a cross section σ^{806 MeV}~17 mb is found at an incident neutron speed of v=2,200 m/s. Extrapolating the short-distance contribution to the physical pion mass and combining the result with phenomenological scattering information and one-body couplings, a cross section of σ^{lqcd}(np→dγ)=334.9(+5.2-5.4) mb is obtained at the same incident neutron speed, consistent with the experimental value of σ^{expt}(np→dγ)=334.2(0.5) mb.
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Affiliation(s)
- Silas R Beane
- Department of Physics, University of Washington, Box 351560, Seattle, Washington 98195, USA
| | - Emmanuel Chang
- Institute for Nuclear Theory, University of Washington, Seattle, Washington 98195-1560, USA
| | - William Detmold
- Center for Theoretical Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Kostas Orginos
- Department of Physics, College of William and Mary, Williamsburg, Virginia 23187-8795, USA
- Jefferson Laboratory, 12000 Jefferson Avenue, Newport News, Virginia 23606, USA
| | - Assumpta Parreño
- Departament d'Estructura i Constituents de la Matèria and Institut de Ciències del Cosmos, Universitat de Barcelona, Martí i Franquès 1, Barcelona, 08028, Spain
| | - Martin J Savage
- Institute for Nuclear Theory, University of Washington, Seattle, Washington 98195-1560, USA
| | - Brian C Tiburzi
- Department of Physics, The City College of New York, New York, New York 10031, USA
- Graduate School and University Center, The City University of New York, New York, New York 10016, USA
- RIKEN BNL Research Center, Brookhaven National Laboratory, Upton, New York 11973, USA
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10
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de Groote RP, Budinčević I, Billowes J, Bissell ML, Cocolios TE, Farooq-Smith GJ, Fedosseev VN, Flanagan KT, Franchoo S, Garcia Ruiz RF, Heylen H, Li R, Lynch KM, Marsh BA, Neyens G, Rossel RE, Rothe S, Stroke HH, Wendt KDA, Wilkins SG, Yang X. Use of a Continuous Wave Laser and Pockels Cell for Sensitive High-Resolution Collinear Resonance Ionization Spectroscopy. PHYSICAL REVIEW LETTERS 2015; 115:132501. [PMID: 26451548 DOI: 10.1103/physrevlett.115.132501] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Indexed: 06/05/2023]
Abstract
New technical developments have led to a 2 orders of magnitude improvement of the resolution of the collinear resonance ionization spectroscopy (CRIS) experiment at ISOLDE, CERN, without sacrificing the high efficiency of the CRIS technique. Experimental linewidths of 20(1) MHz were obtained on radioactive beams of francium, allowing us for the first time to determine the electric quadrupole moment of the short lived [t_{1/2}=22.0(5) ms] ^{219}Fr Q_{s}=-1.21(2) eb, which would not have been possible without the advantages offered by the new method. This method relies on a continuous-wave laser and an external Pockels cell to produce narrow-band light pulses, required to reach the high resolution in two-step resonance ionization. Exotic nuclei produced at rates of a few hundred ions/s can now be studied with high resolution, allowing detailed studies of the anchor points for nuclear theories.
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Affiliation(s)
- R P de Groote
- KU Leuven, Instituut voor Kern-en Stralingsfysica, B-3001 Leuven, Belgium
| | - I Budinčević
- KU Leuven, Instituut voor Kern-en Stralingsfysica, B-3001 Leuven, Belgium
| | - J Billowes
- School of Physics and Astronomy, The University of Manchester, Manchester M13 9PL, United Kingdom
| | - M L Bissell
- KU Leuven, Instituut voor Kern-en Stralingsfysica, B-3001 Leuven, Belgium
- School of Physics and Astronomy, The University of Manchester, Manchester M13 9PL, United Kingdom
| | - T E Cocolios
- School of Physics and Astronomy, The University of Manchester, Manchester M13 9PL, United Kingdom
| | - G J Farooq-Smith
- School of Physics and Astronomy, The University of Manchester, Manchester M13 9PL, United Kingdom
| | - V N Fedosseev
- Engineering Department, CERN, CH-1211 Geneva 23, Switzerland
| | - K T Flanagan
- School of Physics and Astronomy, The University of Manchester, Manchester M13 9PL, United Kingdom
| | - S Franchoo
- Institut de Physique Nucléaire d'Orsay, F-91406 Orsay, France
| | - R F Garcia Ruiz
- KU Leuven, Instituut voor Kern-en Stralingsfysica, B-3001 Leuven, Belgium
| | - H Heylen
- KU Leuven, Instituut voor Kern-en Stralingsfysica, B-3001 Leuven, Belgium
| | - R Li
- Institut de Physique Nucléaire d'Orsay, F-91406 Orsay, France
| | - K M Lynch
- KU Leuven, Instituut voor Kern-en Stralingsfysica, B-3001 Leuven, Belgium
- School of Physics and Astronomy, The University of Manchester, Manchester M13 9PL, United Kingdom
- Physics Department, CERN, CH-1211 Geneva 23, Switzerland
| | - B A Marsh
- Engineering Department, CERN, CH-1211 Geneva 23, Switzerland
| | - G Neyens
- KU Leuven, Instituut voor Kern-en Stralingsfysica, B-3001 Leuven, Belgium
| | - R E Rossel
- Engineering Department, CERN, CH-1211 Geneva 23, Switzerland
- Institut für Physik, Johannes Gutenberg-Universität, D-55128 Mainz, Germany
| | - S Rothe
- Engineering Department, CERN, CH-1211 Geneva 23, Switzerland
| | - H H Stroke
- Department of Physics, New York University, New York, New York 10003, USA
| | - K D A Wendt
- Institut für Physik, Johannes Gutenberg-Universität, D-55128 Mainz, Germany
| | - S G Wilkins
- School of Physics and Astronomy, The University of Manchester, Manchester M13 9PL, United Kingdom
| | - X Yang
- KU Leuven, Instituut voor Kern-en Stralingsfysica, B-3001 Leuven, Belgium
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