Nuclear Theory·nucl-th

Tuesday·April 20, 2021

9 papers—2 primary·7 cross-listed

03
Implications of the $Z_{cs} (3985)$ and $Z_{cs} (4000)$ as two different states
Lu Meng🇩🇪 · Bo Wang🇨🇳 · Guang-Juan Wang🇯🇵 · Shi-Lin Zhu🇨🇳
Recently, the hidden charm tetraquark states $Z_{cs} (3985)$ and $Z_{cs} (4000)$ with strangeness were observed by the BESIII and LHCb collaborations, respectively, which are great breakthroughs for exploring exotic QCD structures. The first and foremost question is whether they are the same state. In this work, we explore the implications of the narrower state $Z_{cs} (3985)$ in BESIII and the wider one $Z_{cs} (4000)$ in LHCb as two different states. Within a solvable nonrelativistic effective field theory, we include the possible violations of heavy quark spin symmetry and SU(3) flavor symmetry in a comprehensive approach. If $Z_{cs} (3985)$ and $Z_{cs} (4000)$ are two different states, our results show that $Z_{cs} (4000) / Z_{cs} (3985)$ is the pure $(∣ D ˉ_{s}^{*} D ⟩ + / - ∣ D ˉ_{s} D^{*} ⟩) / 2$ state, and the SU(3) flavor partner of $Z_{c} (3900)$ is $Z_{cs} (4000)$ rather than the $Z_{cs} (3985)$ . Another two important consequences are the existence of a tensor $D ˉ_{s}^{*} D^{*}$ resonance with mass about 4126 MeV and width 13 MeV, and the suppression of the decay mode $Z_{cs} (3985) \to J / ψ K$ . The two consequences can be tested in experiments and distinguish the two-state interpretation from the one-state scheme.
↳ hep-phhep-exhep-latnucl-thSci.Bull.(2021)·46 citations
04
Violation of Quark-Hadron Duality (The missing oscillation in the OPE)
Santiago Peris (UAB, IFAE and BIST)🇪🇸
The origin of quark-hadron Duality Violations (DVs) can be related to the sigularities of the Laplace transform of the spectral function. With the help of rather generic properties of the large- $N_{c}$ approximation and a generalized form for the radial trajectories found in Regge Theory, we may locate these singularities in the complex plane and obtain an expression for the DVs which turns out to agree with general expectations. Using the two-point vector correlator as a test laboratory, we show how the usual dispersion relation may give rise to perturbation theory, the power corrections from the condensate expansion and DVs.
↳ hep-phhep-lathep-thnucl-th0 citations
05
Novel method for producing very-neutron-rich hypernuclei via charge-exchange reactions with heavy ion projectiles
Takehiko Saito🇯🇵 · Hiroyuki Ekawa🇯🇵 · Manami Nakagawa🇯🇵
We propose a novel method for producing very-neutron-rich hypernuclei and corresponding resonance states by employing charge-exchange reactions via pp( $^{12}$ C, $^{12}$ N $K^{+}$ )n $Λ$ with single-charge-exchange and ppp( $^{9}$ Be, $^{9}$ C $K^{+}$ )nn $Λ$ with double-charge-exchange, both of which produce $Λ K^{+}$ in a target nucleus. The feasibility of producing very-neutron-rich hypernuclei using the proposed method was analysed by applying an ultra-relativistic quantum molecular dynamics model to a $^{6}$ Li+ $^{12}$ C reaction at 2 $A$ GeV. The yields of very-neutron-rich hypernuclei, signal-to-background ratios, and background contributions were investigated. The proposed method is a powerful tool for studying very-neutron-rich hypernuclei and resonance states with a hyperon for experiments employing the Super-FRS facility at FAIR and HFRS facility at HIAF.
↳ nucl-exnucl-thEPJA(2021)·18 citations
06
Born-Oppenheimer potential energy surfaces for Kohn-Sham models in the local density approximation
Yukimi Goto
We show that the Born-Oppenheimer potential energy surface in Kohn-Sham theory behaves like the corresponding one in Thomas-Fermi theory up to $o (R^{- 7})$ for small nuclear separation $R$ . We also prove that if a minimizing configuration exists, then the minimal distance of nuclei is larger than some constant which is independent of the nuclear charges.
↳ math-phmath.MPnucl-thAnnales Henri Poincare(2022)·0 citations
07
Dynamics of equilibration and collisions in ultradilute quantum droplets
Viktor Cikojević🇭🇷 · Leandra Vranješ Markić🇭🇷 · Martí Pi🇪🇸 · Manuel Barranco🇪🇸 · Francesco Ancilotto🇮🇹 · Jordi Boronat🇪🇸
Employing time-dependent density-functional theory, we have studied dynamical equilibration and binary head-on collisions of quantum droplets made of a $^{39}$ K- $^{39}$ K Bose mixture. The phase space of collision outcomes is extensively explored by performing fully three-dimensional calculations with effective single-component QMC based and two-components LHY-corrected mean-field functionals. We exhaustively explored the important effect -- not considered in previous studies -- of the initial population ratio deviating from the optimal mean-field value $N_{2} / N_{1} = a_{11} / a_{22}$ . Both stationary and dynamical calculations with an initial non-optimal concentration ratio display good agreement with experiments. Calculations including three-body losses acting only on the $∣ F, m_{F} ⟩ = ∣1, 0 ⟩$ state show dramatic differences with those obtained with the three-body term acting on the total density.
↳ cond-mat.quant-gasnucl-thphysics.comp-phphysics.flu-dyn+1PRResearch(2021)·7 citations
08
Two-Group Flux Analysis of Neutrons which enter, internally scatter, and often escape a Shielding Layer of Iron -- with respective Group Settings circa one MeV and kilo-eV
Eric V. Steinfelds🇺🇸 · Keith Andrew🇺🇸
It has been long recognized that radiation transport theory is the foundation for the planning and analysis of X-ray (gamma-ray) radiation therapy and for imaging. In less common but appropriate occasions as an alternative to X-rays or gammas, neutron radiation is used in oncological treatments or in imaging of patients. The following work is also potentially of interest to Radiation Safety Planners. Especially in regard to uses for neutron beams, we introduce and present a deterministic and semi-analytical method for doing transport analysis on neutrons and which are judiciously set to be distributed into two energy groups. There are advantages for doing such 2-group and higher multi-group analysis of radiative particles (i.e. neutrons and photons). These advantages are that we can more directly keep track of what percentages of radiative particles are close to the original high energy and how many are at significantly lower energy. For photons, the profile of any build-up function shows that the function is slightly larger than 1.0 at entry, then it rises to perhaps 2 or 3 within roughly one mean free path of the fast primary particles, and finally approaches the asymptote of 1.0 as the penetration depth gets progressively larger. Neutrons deserve a separate treatment. Although it is lengthier, our algorithm and formulation is much more complete than the popular formula used among radiologists where exponential decay is modified with a buildup coefficient. Moreover, a buildup function for neutron fluxes do not appear to be widely offered in radiological and radiation safety publications. This paper demonstrates a method to predict the ratio of high energy (circa 1 MeV) neutrons over low energy neutrons (in a group below 0.201 MeV) which are scattered backwards and forwards out of walls of Fe-56 at various thicknesses.
↳ physics.app-phnucl-thphysics.med-ph0 citations
09
Toward simulating quantum field theories with controlled phonon-ion dynamics: A hybrid analog-digital approach
Zohreh Davoudi🇺🇸 · Norbert M. Linke🇺🇸 · Guido Pagano🇺🇸
Quantum field theories are the cornerstones of modern physics, providing relativistic and quantum mechanical descriptions of physical systems at the most fundamental level. Simulating real-time dynamics within these theories remains elusive in classical computing. This provides a unique opportunity for quantum simulators, which hold the promise of revolutionizing our simulation capabilities. Trapped-ion systems are successful quantum-simulator platforms for quantum many-body physics and can operate in digital, or gate-based, and analog modes. Inspired by the progress in proposing and realizing quantum simulations of a number of relativistic quantum field theories using trapped-ion systems, and by the hybrid analog-digital proposals for simulating interacting boson-fermion models, we propose hybrid analog-digital quantum simulations of selected quantum field theories, taking recent developments to the next level. On one hand, the semi-digital nature of this proposal offers more flexibility in engineering generic model interactions compared with a fully-analog approach. On the other hand, encoding the bosonic fields onto the phonon degrees of freedom of the trapped-ion system allows a more efficient usage of simulator resources, and a more natural implementation of intrinsic quantum operations in such platforms. This opens up new ways for simulating complex dynamics of e.g., Abelian and non-Abelian gauge theories, by combining the benefits of digital and analog schemes.
↳ quant-phcond-mat.quant-gashep-latnucl-thPRResearch(2021)·108 citations

Affiliations

first authorsco-authorsvia INSPIRE

Implications of the Zcs​(3985) and Zcs​(4000) as two different states

Violation of Quark-Hadron Duality (The missing oscillation in the OPE)

Novel method for producing very-neutron-rich hypernuclei via charge-exchange reactions with heavy ion projectiles

Born-Oppenheimer potential energy surfaces for Kohn-Sham models in the local density approximation

Dynamics of equilibration and collisions in ultradilute quantum droplets

Two-Group Flux Analysis of Neutrons which enter, internally scatter, and often escape a Shielding Layer of Iron -- with respective Group Settings circa one MeV and kilo-eV

Toward simulating quantum field theories with controlled phonon-ion dynamics: A hybrid analog-digital approach

Affiliations

Implications of the $Z_{cs} (3985)$ and $Z_{cs} (4000)$ as two different states