Nuclear Theory·nucl-th

Thursday·February 17, 2022

8 papers—2 primary·6 cross-listed

01
Can nuclear matter consist of $α$ -particles?
B. E. Grinyuk🇺🇦
A sufficient condition for the spatial collapse in an infinite system of interacting Bose particles is obtained on the basis of the variational principle with the use of trial functions with the Jastrow pair correlation factors. The instability of a hypothetical infinite system of $α$ -particles with respect to the spatial collapse is shown under the assumption of the Ali - Bodmer interaction potentials between such Bose particles. Thus, it becomes clear why the hypothetical nuclear matter is naturally treated with the use of at least the nucleon degrees of freedom.
nucl-thcond-mat.otherquant-phUkr.J.Phys.(2022)·0 citations
02
Magnetic field induced hair structure in charmonium gluon-dissociation
Jin Hu🇨🇳 · Shuzhe Shi🇨🇦 · Zhe Xu🇨🇳 · Jiaxing Zhao🇨🇳 · Pengfei Zhuang🇨🇳
We study electromagnetic field effect on charmonium gluon-dissociation in quark-gluon plasma. With the effective Hamiltonian derived from QCD multipole expansion under an external electromagnetic field, we first solve the two-body Schrödinger equation for a pair of charm quarks with mean field potentials for color and electromagnetic interactions and obtain the charmonium binding energies and wave functions, and then calculate the gluon-dissociation cross-section and decay width by taking the color electric and magnetic dipole interactions as perturbations above the mean field and employing Fermi's Golden Rule. Considering the charmonium deformation in magnetic field, the discrete Landau energy levels make the dissociation cross-section grow hair, and the electric dipole channel is significantly changed, especially for the $P -$ wave states $χ_{c 0}$ and $χ_{c \pm}$ . From our numerical calculation, the magnetic field strength $e B = 5 m_{π}^{2}$ already changes the gluon dissociation strongly, which may indicate measurable effects in high-energy nuclear collisions.
nucl-thhep-phPRD(2022)·12 citations
03
Decays of Roper-like singly heavy baryons in a chiral model
Daiki Suenaga🇯🇵 · Atsushi Hosaka🇯🇵
We present a chiral model describing decays of the Roper-like $Λ_{c} (2765)$ and $Ξ_{c} (2970)$ as well as those of the heavy quark spin-doublet ${Σ_{c} (2455), Σ_{c} (2520)}$ and ${Ξ_{c}^{'}, Ξ_{c} (2645)}$ , by focusing on chiral representations of diquarks inside the heavy baryons. Based on our chiral model together with the heavy quark spin symmetry, we derive a relation satisfied by axial charges of the heavy baryons that controls magnitude of their one pion (kaon) decays. Besides, it is shown that the large decay widths of the Roper-like $Λ_{c} (2765)$ and $Ξ_{c} (2970)$ , which cannot be implemented by conventional non-relativistic quark models, are explained by reasonable values of the axial charges. In addition, we apply the chiral model to bottom baryons and predict decay widths of the undiscovered Roper-like $Ξ_{b}$ . We expect that our present investigation leads to elucidation of dynamical properties of the excited heavy baryons from the viewpoint of chiral symmetry.
↳ hep-phnucl-thPRD(2022)·13 citations
04
Static and Dynamic Bethe-Salpeter Equations in the $T$ -Matrix Approximation
Pierre-François Loos🇫🇷 · Pina Romaniello🇫🇷
While the well-established $G W$ approximation corresponds to a resummation of the direct ring diagrams and is particularly well suited for weakly-correlated systems, the $T$ -matrix approximation does sum ladder diagrams up to infinity and is supposedly more appropriate in the presence of strong correlation. Here, we derive and implement, for the first time, the static and dynamic Bethe-Salpeter equations when one considers $T$ -matrix quasiparticle energies as well as a $T$ -matrix-based kernel. The performance of the static scheme and its perturbative dynamical correction are assessed by computing the neutral excited states of molecular systems. Comparison with more conventional schemes as well as other wave function methods are also reported. Our results suggest that the $T$ -matrix-based formalism performs best in few-electron systems where the electron density remains low.
↳ physics.chem-phcond-mat.mtrl-scicond-mat.str-elnucl-th+1J.Chem.Phys.(2022)·5 citations
05
Elastic pion-proton and pion-pion scattering at high energies in holographic QCD
Zhibo Liu🇨🇳 · Wei Xie🇨🇳 · Fei Sun🇨🇳 · Shuang Li🇨🇳 · Akira Watanabe🇨🇳
The total and differential cross sections of high energy pion-proton and pion-pion scattering are investigated in a holographic QCD model, focusing on the Regge regime in which the Pomeron exchange gives the dominant contribution to those cross sections. The Pomeron is described by the Reggeized spin-2 particle propagator, and the hadron-Pomeron couplings are given by gravitational form factors of the hadrons, which are obtained from the bottom-up AdS/QCD models. Since the parameters, which characterize the Pomeron trajectory, have been determined in a preceding study of the proton-proton scattering, the pion-proton cross sections can be expressed with a single adjustable parameter. Once this parameter is determined by the experimental data of the pion-proton total cross section, its differential cross section and the pion-pion cross sections can be calculated without any additional parameter. Although the currently available data are limited, it is found that our calculation is consistent with those. Our predictions are explicitly shown, and the present model can be tested at the future experimental facilities.
↳ hep-phhep-exnucl-exnucl-thPRD(2022)·13 citations
06
1-jettiness with jet axis at $O (α_{s})$ in jeep inelastic scattering
Zexuan Chu🇨🇳 · Yunlu Wang🇨🇳 · June-Haak Ee🇨🇳 · Jinhui Chen🇨🇳 · Daekyoung Kang🇨🇳
We present $O (α_{s})$ analytic predictions for event shape 1-jettiness $τ_{1}$ distribution aiming measurements in deep inelastic scattering process at future Electron Ion Colliders. The result depends on conventional variables $x$ and $Q$ as well as on $τ_{1}$ and is relatively compact and easy to implement for numerical calculation. Three different choices of axis, with respect to which $τ_{1}$ is measured are considered in the Breit frame. The first is the one optimally adjusted to minimize $τ_{1}$ and the second and third are taken from anti- $k_{T}$ and Centauro jet algorithms defined with a jet radius parameter $R$ , respectively. We find that the first and second give the same result at this order and are independent of $R$ , while the third depends on the radius. This fixed-order result provides a nonsingular contribution to be combined with a singular log-resummed contribution to give the full spectrum in $τ_{1}$ space and also shows how fixed-order and resummation regions change as a function of $x$ and $Q$ .
↳ hep-phnucl-exnucl-thJHEP(2022)·10 citations
07
Investigation of the MicroBooNE neutrino cross sections on Argon
M. Martini🇫🇷 · M. Ericson🇫🇷 · G. Chanfray🇫🇷
Experimental data of charged current inclusive neutrino cross sections on argon as a function of different variables have recently appeared. We have compared them to our theoretical approach. Overall we find an agreement in spite of a tendency of underestimation in some specific regions. A new aspect is the availability of data in terms of the energy transfer to the nucleus, which allows a better separation of the different reaction mechanisms. We explain the deterioration of agreement in specific kinematical conditions by the absence in our model of two-pion production and other inelastic channels, more important for MicroBooNE than for T2K.
↳ hep-phhep-exnucl-thPRC(2022)·10 citations
08
Nuclear information entropy, gravitational form factor, and glueballs in AdS/QCD
G. Karapetyan🇧🇷 · R. da Rocha🇧🇷
The nuclear configurational entropy (NCE) is employed to derive two parameters encoding the Pomeron Regge trajectory and the spectrum of closed strings, which are also related to the glueball mass, precisely matching data of the TOTEM collaboration at the LHC. In the Regge regime of holographic QCD, the (Reggeized) glueball propagator and the gravitational form factor of the proton occupy a relevant spot in AdS/QCD. They are used for deriving the cross-sections for the TeV scale proton-proton scattering process, which are the main ingredient for computing the NCE. The nuclear configurational stability is also addressed.
↳ hep-phhep-thnucl-thEur.Phys.J.Plus(2022)·5 citations

Affiliations

first authorsco-authorsvia INSPIRE