PaperPanorama

Nuclear Theory·nucl-th

Friday·March 29, 2024

10 papers6 primary·4 cross-listed

  1. 07

    [Submitted on 27 Mar 2024] (cross-list from hep-ph)

    Prospects for PIONEER

    Martin Hoferichter

    Pion decay, , offers a pristine way to measure the CKM matrix element in a purely mesonic system, with excellent control over the hadronic matrix elements. We review the physics goals and current status of the PIONEER experiment, which aims at major improvements in the branching fractions for the decay in Phase I and for pion decay in Phases II and III of its experimental program, potentially leading to a measurement of competitive with determinations from decays involving nucleons.

    Comments:
    6+3 pages, 4 figures; presented at the 12th Workshop on the CKM Unitarity Triangle, 18-22 September 2023, Santiago de Compostela
    Subjects:
    High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); Nuclear Theory (nucl-th)
    arXiv:
    2403.18889 [pdf]
    2 citations
  2. 08

    [Submitted on 27 Mar 2024] (cross-list from hep-th)

    Exact evaluation of large-charge correlation functions in non-relativistic conformal field theory

    Silas R. Beane🇨🇭 · Domenico Orlando🇨🇭 · Susanne Reffert🇨🇭

    The large-charge master field which generates all n-point correlation functions with an insertion of large charge Q in non-relativistic conformal field theory is obtained. This field is used to compute Schrödinger-invariant n-point correlation functions of large-charge operators via a direct evaluation of the path integral. Conformal dimensions are found to agree with calculations based on the state-operator correspondence. The master field solution exhibits an emergent harmonic trap whose frequency is a function of the Euclidean time. The large-charge effective action with operator insertions describes a droplet of superfluid matter whose spatial size scales with the time separation of sources. The solution is used to compute Schrödinger symmetry breaking corrections in the large-charge effective field theory (EFT) due to a finite scattering length in the fundamental theory of fermions near unitarity. The scaling of these effects in the large-charge power counting scheme is established, and the size of the effects is quantified using input from quantum Monte Carlo simulations of the near-unitary gas, as well as from the large-N expansion at large charge.

    Comments:
    30 pages, 5 figures, minor errors corrected
    Subjects:
    High Energy Physics — Theory (hep-th); Quantum Gases (cond-mat.quant-gas); High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
    arXiv:
    2403.18898 [pdf]
    PRD(2024)·5 citations
  3. 09

    [Submitted on 28 Mar 2024] (cross-list from physics.chem-ph)

    Reference Energies for Double Excitations: Improvement and Extension

    Fábris Kossoski · Martial Boggio-Pasqua · Pierre-François Loos · Denis Jacquemin

    In the realm of photochemistry, the significance of double excitations (also known as doubly-excited states), where two electrons are concurrently elevated to higher energy levels, lies in their involvement in key electronic transitions essential in light-induced chemical reactions as well as their challenging nature from the computational theoretical chemistry point of view. Based on state-of-the-art electronic structure methods (such as high-order coupled-cluster, selected configuration interaction, and multiconfigurational methods), we improve and expand our prior set of accurate reference excitation energies for electronic states exhibiting a substantial amount of double excitations [http://dx.doi.org/10.1021/acs.jctc.8b01205; Loos et al. J. Chem. Theory Comput. 2019, 15, 1939]. This extended collection encompasses 47 electronic transitions across 26 molecular systems that we separate into two distinct subsets: (i) 28 "genuine" doubly-excited states where the transitions almost exclusively involve doubly-excited configurations and (ii) 19 "partial" doubly-excited states which exhibit a more balanced character between singly- and doubly-excited configurations. For each subset, we assess the performance of high-order coupled-cluster (CC3, CCSDT, CC4, and CCSDTQ) and multiconfigurational methods (CASPT2, CASPT3, PC-NEVPT2, and SC-NEVPT2). Using as a probe the percentage of single excitations involved in a given transition () computed at the CC3 level, we also propose a simple correction that reduces the errors of CC3 by a factor of 3, for both sets of excitations. We hope that this more complete and diverse compilation of double excitations will help future developments of electronic excited-state methodologies.

    Comments:
    25 pages, 3 figures (Supporting Information available)
    Subjects:
    physics.chem-ph (physics.chem-ph); cond-mat.mtrl-sci (cond-mat.mtrl-sci); Strongly Correlated Electrons (cond-mat.str-el); Nuclear Theory (nucl-th)
    arXiv:
    2403.19597 [pdf]
    J.Chem.Theor.Comput.(2024)·1 citation
  4. 10

    [Submitted on 28 Mar 2024] (cross-list from hep-ph)

    Angular dependence in transverse momentum dependent diffractive parton distributions at small-

    Yoshitaka Hatta🇺🇸 · Feng Yuan🇺🇸

    We discuss the angular dependence of the recently proposed transverse momentum dependent quark and gluon diffractive parton distributions at small-. We introduce the difractive versions of the Sivers function and the elliptic gluon Wigner distribution and evaluate them in simple models with gluon saturation and study their geometric scaling properties. We also show that the diffractive version of the linearly polarized gluon distribution identically vanishes to leading order. These distributions enrich the physics opportunities for measuring semi-inclsuive diffractive DIS processes at the future electron-ion colliders.

    Comments:
    9 pages, 5 figures
    Subjects:
    High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
    arXiv:
    2403.19609 [pdf]
    PLB(2024)·14 citations

Affiliations

first authorsco-authorsvia INSPIRE