Tue·Jun 18, 2019Tuesday·June 18, 2019

1. 01*

   Investigation of the quasi-free domain in deuteron-deuteron break-up using spin observables

   R. Ramazani-Sharifabadi🇮🇷 · M.T. Bayat · I. Ciepał🇵🇱 · N. Kalantar-Nayestanaki🇳🇱 · St. Kistryn🇵🇱 · A. Kozela🇵🇱 · M. Mahjour-Shafiei🇮🇷 · J.G. Messchendorp🇳🇱 · M. Mohammadi-Dadkan🇳🇱 · A. Ramazani-Moghaddam-Arani · E. Stephan🇵🇱 · H. Tavakoli-Zaniani🇳🇱

   Precision measurements of vector and tensor analyzing powers of the ${}^2\mathrm{H}(\vec{d},dp)n$ break-up process for configurations in the vicinity of the quasi-free scattering regime with the neutron as spectator, are presented. These measurements are performed with a polarized deuteron-beam with an energy of 65 MeV/nucleon impinging on a liquid-deuterium target. The experiment was conducted at the AGOR facility at KVI using the BINA 4$\pi$-detection system. Events for which the final-state deuteron and proton are coplanar have been analyzed and the data have been sorted for various momenta of the missing neutron. In the limit of vanishing neutron momentum and at large deuteron-proton momentum transfer, the data agree well with the measured and theoretically predicted spin observables of the elastic deuteron-proton scattering process. The agreement deteriorates rapidly with increasing neutron momentum and/or decreasing momentum transfer from the deuteron beam to the outgoing proton. This study reveals the presence of a significant contribution of final-state interactions even at very small neutron momenta.

   nucl-exEPJA(2019)·6 citations
2. 02*

   Search for triple and quadruple beta decay of ${}^{150}$Nd

   A.S. Barabash🇷🇺 · Ph. Hubert🇫🇷 · A. Nachab🇲🇦 · V.I. Umatov🇷🇺

   Triple beta decay of ${}^{150}$Nd to the ground and excited states of ${}^{150}$Eu and quadruple beta decay of ${}^{150}$Nd to the excited states of ${}^{150}$Gd have been studied using a 400 cm${}^3$ low-background HPGe detector and an external source consisting of 3046 g of natural Nd${}_2$O${}_3$ powder. A half-life limit for the quadruple beta decay to the 0${}_1^{+}$ state of ${}^{150}$Gd was found to be $T_{1/2}(0\nu +4\nu )>8.7\times 10^{20}$ yr (90\% C.L.). For other (0$\nu$+4$\nu$) transitions to the 2${}_1^{+}$, 3${}_1^{-}$, 4${}_1^{+}$, 2${}_2^{+}$ and 2${}_3^{+}$ excited states limits for the first time have been obtained at the level of $(6.1-9.5)\times 10^{20}$ yr (90\% C.L.). We report here also the results for the first search for triple beta decay to the ground and excited final states of ${}^{150}$Eu. We find no evidence of this decay and set lower limits on the half-life in the range $T_{1/2}(0\nu +3\nu )>(0.04-4.8)\times 10^{20}$ yr (90\% C.L.).

   nucl-exPRC(2019)·3 citations
3. 03*

   High-K isomer and the rotational properties in the odd-Z neutron-rich nucleus ${}^{163}$Eu

   Xiao-Tao He🇨🇳 · Ze-Long Chen

   The newly observed isomer and ground-state band in the odd-Z neutron-rich rare-earth nucleus ${}^{163}$Eu are investigated by using the cranked shell model (CSM) with pairing treated by the particle-number conserving (PNC) method. This is the first time detailed theoretical investigations are performed of the observed $964(1)$ keV isomer and ground-state rotational band in ${}^{163}$Eu. The experimental data are reproduced very well by the theoretical results. The configuration of the $964(1)$ keV isomer is assigned as the three-particle state ${\frac{13}{2}}^{-}(\nu {\frac{7}{2}}^{+}[633]\otimes \nu {\frac{1}{2}}^{-}[521]\otimes \pi {\frac{5}{2}}^{+}[413]$). More low-lying multi-particle states are predicted in ${}^{163}$Eu. Due to its significant effect on the nuclear mean field, the high-order ${\epsilon }_6$ deformation plays an important role in the energy and configuration assignment of the multi-particle states. Compared to its neighboring even-even nuclei ${}^{162}$Sm and ${}^{164}$Gd, there is a $10\%\sim 15\%$ increase of $J^{(1)}$ of the one-particle ground-state band in ${}^{163}$Eu. This is explained by the pairing reduction due to the blocking of the nucleon on the proton $\pi {\frac{5}{2}}^{+}$[413] orbital in ${}^{163}$Eu.

   ↳ nucl-thnucl-exCPC(2019)·4 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.