Nuclear Theory·nucl-th

Friday·June 9, 2017

9 papers—5 primary·4 cross-listed

01
[Submitted on 7 Jun 2017]
Analytic predictions for nuclear shapes, the prolate dominance and the prolate-oblate shape transition in the proxy-SU(3) model
Dennis Bonatsos · I. E. Assimakis · N. Minkov · Andriana Martinou · S. Sarantopoulou · R. B. Cakirli · R. F. Casten · K. Blaum
Using a new approximate analytic parameter-free proxy-SU(3) scheme, we make simple predictions of shape observables for deformed nuclei, namely gamma and beta deformation variables, the global feature of prolate dominance and the locus of the prolate-oblate shape transition. The predictions are compared with empirical results.
Comments:
14 pages, 6 figures, 4 tables
Subjects:
Nuclear Theory (nucl-th)
arXiv:
1706.02321 [pdf]
PRC(2017)·113 citations
02
[Submitted on 8 Jun 2017]
On the properties of the $^{229}$ Th isotope
V.I. Isakov
Electromagnetic properties of the deformed neutron-odd nucleus $^{229}$ Th are investigated in the framework of the unified model, with primary emphasis upon the properties of the low-lying isomeric state.
Comments:
10 pages, one figure
Subjects:
Nuclear Theory (nucl-th)
arXiv:
1706.02517 [pdf]
0 citations
03
[Submitted on 8 Jun 2017]
Shell model based deformation analysis of light Cadmium isotopes
T. Schmidt · K. L. G. Heyde · A. Blazhev · J. Jolie
Large-scale shell-model calculations for the even-even Cadmium isotopes 98 Cd - 108 Cd have been performed with the ANTOINE code in the {\pi}(2p 1/2 ; 1g 9/2 ) {\nu}(2d 5/2 ; 3s 1/2 ; 2d 3/2 ; 1g 7/2 ; 1h 11/2 ) model space without further truncation. Known experimental energy levels and B(E2) values could be well reproduced. Taking these calculations as a starting ground we analyze the deformation parameters predicted for the Cd isotopes as a function of neutron number N and spin J using the methods of model independent invariants introduced by K. Kumar and D. Cline.
Subjects:
Nuclear Theory (nucl-th)
arXiv:
1706.02544 [pdf]
PRC(2017)·34 citations
04
[Submitted on 8 Jun 2017]
Three--Dimensional parton structure of light nuclei
Sergio Scopetta🇮🇹 · Alessio Del Dotto🇮🇹 · Leonid Kaptari🇷🇺 · Emanuele Pace🇮🇹 · Matteo Rinaldi🇪🇸 · Giovanni Salmè🇮🇹
Two promising directions beyond inclusive deep inelastic scattering experiments, aimed at unveiling the three dimensional structure of the bound nucleon, are reviewed, considering in particular the $^{3}$ He nucleus. The 3D structure in coordinate space can be accessed through deep exclusive processes, whose non-perturbative part is encoded in generalized parton distributions (GPDs). In this way, the distribution of partons in the transverse plane can be obtained. As an example, coherent deeply virtual Compton scattering (DVCS) off $^{3}$ He nuclei, important to access the neutron GPDs, will be discussed. In Impulse Approximation (IA), the sum of two GPDs of $^{3}$ He, $H$ and $E$ , at low momentum transfer, turns out to be dominated by the neutron contribution. Besides, a technique, able to take into account the nuclear effects included in the Impulse Approximation analysis, has been developed. The spin dependent GPD $H ~$ of $^{3}$ He is also found to be largely dominated, at low momentum transfer, by the neutron contribution. Semi-inclusive deep inelastic scattering processes access the momentum space 3D structure parameterized through transverse momentum dependent parton distributions. A distorted spin-dependent spectral function has been recently introduced for $^{3}$ He, in a non-relativistic framework, to take care of the final state interaction between the observed pion and the remnant in semi-inclusive deep inelastic electron scattering off transversely polarized $^{3}$ He. The calculation of the Sivers and Collins single spin asymmetries for $^{3}$ He, and a straightforward procedure to effectively take into account nuclear dynamics and final state interactions, will be reviewed. The Light-front dynamics generalization of the analysis is also addressed.
Comments:
10 pages, 5 figures, invited talk at the "15th Conference on Theoretical Nuclear Physics in Italy (TNPI16)", Pisa, Italy, 20-22 April 2016. To appear in the Proceedings
Subjects:
Nuclear Theory (nucl-th); High Energy Physics — Phenomenology (hep-ph)
arXiv:
1706.02626 [pdf]
J.Phys.Conf.Ser.(2018)·0 citations
05
[Submitted on 8 Jun 2017]
Charge and Magnetic Properties of Three-Nucleon Systems in Pionless Effective Field Theory
Jared Vanasse
A method to calculate the form factor for an external current with non-derivative coupling for the three-body system in an effective field theory (EFT) of short-range interactions is shown. Using this method the point charge radius of $^{3} He$ is calculated to next-to-next-to-leading order (NNLO) in pionless EFT ( $EFT (\neq π)$ ), and the magnetic moment and magnetic radius of $^{3} H$ and $^{3} He$ are calculated to next-to-leading order (NLO). For the $^{3} He$ charge and magnetic form factors Coulomb interactions are ignored. The $^{3} He$ point charge radius is given by 1.74(4) fm at NNLO. This agrees well with the experimental $^{3} He$ point charge radius of 1.7753(54) fm [Angeli and Marinova, At. Data Nucl. Data Tables 99, 69 (2013)]. The $^{3} H$ ( $^{3} He$ ) magnetic moment in units of nuclear magnetons is found to be 2.92(35) (-2.08(25)) at NLO in agreement with the experimental value of 2.979 (-2.127). For $^{3} H$ ( $^{3} He$ ) the NLO magnetic radius is 1.78(11) fm (1.85(11) fm) which agrees with the experimental value of 1.840(182) fm (1.965(154) fm) [I. Sick, Prog. Part. Nucl. Phys. 47, 245 (2001)]. The fitting of the low-energy constant $L_{1}$ of the isovector two-body magnetic current and the consequences of Wigner-SU(4) symmetry for the three-nucleon magnetic moments are also discussed.
Comments:
v1: 38 pages 6 figures
Subjects:
Nuclear Theory (nucl-th)
arXiv:
1706.02665 [pdf]
PRC(2018)·25 citations
06
[Submitted on 22 May 2017] (cross-list from hep-ph)
Renormalized quark-antiquark Hamiltonian induced by a gluon mass ansatz in heavy-flavor QCD
Stanisław D. Głazek🇵🇱 · María Gómez-Rocha🇮🇹 · Jai More🇮🇳 · Kamil Serafin🇵🇱
In response to the growing need for theoretical tools that can be used in QCD to describe and understand the dynamics of gluons in hadrons in the Minkowski space-time, the renormalization group procedure for effective particles (RGPEP) is shown in the simplest available context of heavy quarkonia to exhibit a welcome degree of universality in the first approximation it yields once one assumes that beyond perturbation theory gluons obtain effective mass. Namely, in the second-order terms, the Coulomb potential with Breit-Fermi spin couplings in the effective quark-antiquark component of a heavy quarkonium, is corrected in one-flavor QCD by a spin-independent harmonic oscillator term that does not depend on the assumed effective gluon mass or the choice of the RGPEP generator. The new generator we use here is much simpler than the ones used before and has the advantage of being suitable for studies of the effective gluon dynamics at higher orders than the second and beyond the perturbative expansion.
Comments:
8 pages, 2 figures, journal version
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Theory (hep-th); Nuclear Theory (nucl-th)
arXiv:
1705.07629 [pdf]
PLB(2017)·35 citations
07
[Submitted on 8 Jun 2017] (cross-list from hep-ph)
On neutrino production of a charmed meson
J. Wagner🇵🇱 · B. Pire🇫🇷 · L. Szymanowski🇵🇱
We calculate in the framework of the collinear QCD approach the amplitude for exclusive neutrino-production of a pseudoscalar charmed $D$ meson. This process allows to access gluon and both chiral-odd and chiral-even quark generalized parton distributions (GPDs), which contribute in specific ways to the amplitude for different polarization states of the $W$ boson. The energy dependence of the cross section allows to separate different contributions and the measurement of the azimuthal dependence helps to single out the transversity chiral-odd GPDs contributions. The flavor dependence, and in particular the difference between $D^{+}$ and $D^{0}$ production rates, allows to test the importance of gluonic contributions. The behaviour of the proton and neutron target cross sections enables to separate the $u$ and $d$ quark contributions. Planned medium and high energy neutrino facilities will thus allow some important progress in the realm of hadronic physics.
Comments:
5 pages, 8 figures, contribution to DIS 2017, XXV International Workshop on Deep-Inelastic Scattering and Related Subjects, 3-7 April 2017, University of Birmingham, UK
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
1706.02461 [pdf]
PoS(2018)·1 citation
08
[Submitted on 8 Jun 2017] (cross-list from hep-ph)
Heavy Baryon-Antibaryon Molecules in Effective Field Theory
Jun-Xu Lu🇨🇳 · Li-Sheng Geng🇨🇳 · Manuel Pavon Valderrama🇨🇳
We discuss the effective field theory description of bound states composed of a heavy baryon and antibaryon. This framework is a variation of the ones already developed for heavy meson-antimeson states to describe the $X (3872)$ or the $Z_{c}$ and $Z_{b}$ resonances. We consider the case of heavy baryons for which the light quark pair is in S-wave and we explore how heavy quark spin symmetry constrains the heavy baryon-antibaryon potential. The one pion exchange potential mediates the low energy dynamics of this system. We determine the relative importance of pion exchanges, in particular the tensor force. We find that in general pion exchanges are probably non-perturbative for the $Σ_{Q} Σ ˉ_{Q}$ , $Σ_{Q}^{*} Σ ˉ_{Q}$ and $Σ_{Q}^{*} Σ ˉ_{Q}^{*}$ systems, while for the $Ξ_{Q}^{'} Ξ ˉ_{Q}^{'}$ , $Ξ_{Q}^{*} Ξ ˉ_{Q}^{'}$ and $Ξ_{Q}^{*} Ξ ˉ_{Q}^{*}$ cases they are perturbative If we assume that the contact-range couplings of the effective field theory are saturated by the exchange of vector mesons, we can estimate for which quantum numbers it is more probable to find a heavy baryonium state. The most probable candidates to form bound states are the isoscalar $Λ_{Q} Λ ˉ_{Q}$ , $Σ_{Q} Σ ˉ_{Q}$ , $Σ_{Q}^{*} Σ ˉ_{Q}$ and $Σ_{Q}^{*} Σ ˉ_{Q}^{*}$ and the isovector $Λ_{Q} Σ ˉ_{Q}$ and $Λ_{Q} Σ ˉ_{Q}^{*}$ systems, both in the hidden-charm and hidden-bottom sectors. Their doubly-charmed and -bottom counterparts ( $Λ_{Q} Λ_{Q}$ , $Λ_{Q} Σ_{Q}^{(*)}$ , $Σ_{Q}^{(*)} Σ_{Q}^{(*)}$ ) are also good candidates for binding.
Comments:
38 pages, 1 figure, 12 tables; extended discussion on the most probable molecular heavy baryon-antibaryon states to bind; corresponds to published version
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); High Energy Physics — Lattice (hep-lat); Nuclear Theory (nucl-th)
arXiv:
1706.02588 [pdf]
PRD(2019)·54 citations
09
[Submitted on 8 Jun 2017] (cross-list from hep-ph)
Nuclear-bound quarkonia and heavy-flavor hadrons
G. Krein🇧🇷 · A.W. Thomas🇦🇺 · K. Tsushima🇧🇷
In our quest to win a deeper understanding of how QCD actually works, the study of the binding of heavy quarkonia and heavy-flavor hadrons to atomic nuclei offers enormous promise. Modern experimental facilities such as FAIR, Jefferson Lab at 12 GeV and J-PARC offer exciting new experimental opportunities to study such systems. These experimental advances are complemented by new theoretical approaches and predictions, which will both guide these experimental efforts and be informed and improved by them. This review will outline the main theoretical approaches, beginning with QCD itself, summarize recent theoretical predictions and relate them both to past experiments and those from which we may expect results in the near future.
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
1706.02688 [pdf]
PPNP(2018)·126 citations

Affiliations

first authorsco-authorsvia INSPIRE