Fri·Oct 24, 2014Friday·October 24, 2014

1. 01*

   High-precision Measurements of piP Elastic Differential Cross Sections in the Second Resonance Region

   I.G. Alekseev🇷🇺 · V.A. Andreev🇷🇺 · I.G. Bordyuzhin🇷🇺 · W.J. Briscoe🇺🇸 · Ye.A. Filimonov🇷🇺 · V.V. Golubev🇷🇺 · A.B. Gridnev🇷🇺 · D.V. Kalinkin🇷🇺 · L.I. Koroleva🇷🇺 · N.G. Kozlenko🇷🇺 · V.S. Kozlov🇷🇺 · A.G. Krivshich🇷🇺 and 13 other authors

   Cross sections for pi+-p elastic scattering have been measured to high precision, for beam momenta between 800 and 1240 MeV/c, by the EPECUR Collaboration, using the ITEP proton synchrotron. The data precision allows comparisons of the existing partial-wave analyses (PWA) on a level not possible previously. These comparisons imply that updated PWA are required.

   nucl-exhep-exhep-phnucl-thPRC(2015)·18 citations
2. 02*

   Consequences of omitting spin-orbit partner configurations on B(E2)'s and quadrupole moments in nuclei

   Larry Zamick🇺🇸 · Yitzhak Sharon🇺🇸 · Shadow Robinson🇺🇸 · Matthew Harper

   Calculations of B(E2)'s and quadruplole moments in the g_{9/2 region below ^{100} Sn are hampered by the fact that the inclusion of the g_{7/2}configuration leads to model spaces that are too large to handle. We therefore examine lighter nuclei if the fp region where one can easily include all the orbitals, f,{}_{7/2}, p_{3/2}, p_{1/2}and f_{5/2} . We perform such calculations but then take a step back and exclude the f_{5/2} orbital. By comparing the 2 calculations we can hope to get insight into the importance of the missing spin-orbit partner in other regions.

   ↳ nucl-thnucl-exPRC(2015)·3 citations
3. 03*

   Constraints on the $\omega \pi$ form factor from analyticity and unitarity

   B. Ananthanarayan🇮🇳 · I. Caprini🇷🇴 · B. Kubis🇩🇪

   Motivated by the discrepancies noted recently between the theoretical calculations of the electromagnetic $\omega \pi$ form factor and certain experimental data, we investigate this form factor using analyticity and unitarity in a framework known as the method of unitarity bounds.We use a QCD correlator computed on the spacelike axis by operator product expansion and perturbative QCD as input, and exploit unitarity and the positivity of its spectral function, including the two-pion contribution that can be reliably calculated using high-precision data on the pion form factor. From this information, we derive upper and lower bounds on the modulus of the $\omega \pi$ form factor in the elastic region. The results provide a significant check on those obtained with standard dispersion relations, confirming the existence of a disagreement with experimental data in the region around 0.6 GeV.

   ↳ hep-phhep-exnucl-exEPJC(2014)·32 citations
4. 04*

   Systematic study of nuclear matrix elements in neutrinoless double-beta decay with a beyond mean-field covariant density functional theory

   J. M. Yao🇯🇵 · L. S. Song🇨🇳 · K. Hagino🇯🇵 · P. Ring🇩🇪 · J. Meng🇨🇳

   We report a systematic study of nuclear matrix elements (NMEs) in neutrinoless double-beta decays with a state-of-the-art beyond mean-field covariant density functional theory. The dynamic effects of particle-number and angular-momentum conservations as well as quadrupole shape fluctuations are taken into account with projections and generator coordinate method for both initial and final nuclei. The full relativistic transition operator is adopted to calculate the NMEs. The present systematic studies show that in most of the cases there is a much better agreement with the previous non-relativistic calculation based on the Gogny force than in the case of the nucleus ${}^{150}$Nd found in Song et al. [Phys. Rev. C 90, 054309 (2014)]. In particular, we find that the total NMEs can be well approximated by the pure axial-vector coupling term with a considerable reduction of the computational effort.

   ↳ nucl-thhep-exhep-phnucl-exPRC(2015)·185 citations
5. 05*

   Fully damped Mott oscillations in sub-barrier elastic scattering of identical heavy ions and the nuclear interaction

   M. S. Hussein🇧🇷 · L. F. Canto🇧🇷 · W. Mittig🇺🇸

   We investigate the possible disappearance of Mott oscillations in the scattering of bosonic nuclei at sub-barrier energies. This effect is universal and happens at a critical value of the Sommerfeld parameter. It is also found that the inclusion of the short-range nuclear interaction has a profound influence on this phenomenon. Thus we suggest that the study of this lack of Mott oscillation, which we call, "transverse isotropy" is a potentially useful mean to study the nuclear interaction.

   ↳ nucl-thnucl-exJ.Phys.Conf.Ser.(2015)·0 citations
6. 06*

   Four-body effects on 9Be + 208Pb scattering and fusion around the Coulomb barrier

   P. Descouvemont🇧🇪 · T. Druet · L. F. Canto🇧🇷 · M. S. Hussein🇧🇷

   We investigate the 9Be + 208Pb elastic scattering and fusion at energies around the Coulomb barrier. The ${}^9$Be nucleus is described in a \alpha + \alpha + n three-body model, using the hyperspherical coordinate method. The scattering with ${}^{208}$Pb is then studied with the Continuum Discretized Coupled Channel (CDCC) method, where the \alpha + \alpha + n continuum is approximated by a discrete number of pseudostates. Optical potentials for the $\alpha {+}^{208}$Pb and $n{+}^{208}$Pb systems are taken from the literature. We present elastic-scattering and fusion cross sections at different energies, and investigate the convergence with respect to the truncation of the \alpha + \alpha + n continuum. A good agreement with experiment is obtained, considering that there is no parameter fitting. We show that continuum effects increase at low energies.

   ↳ nucl-thnucl-exJ.Phys.Conf.Ser.(2015)·3 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.