Tue·Mar 8, 2022Tuesday·March 8, 2022

1. 01*

   Progress in understanding short-range structure in nuclei: an experimental perspective

   John Arrington🇺🇸 · Nadia Fomin🇺🇸 · Axel Schmidt🇺🇸

   High-energy electron scattering is a clean and precise probe for measurements of hadronic and nuclear structure, with a key role in understanding the role of high-momentum nucleons (and quarks) in nuclei. Jefferson Lab has dramatically expanded our understanding of the high-momentum nucleons generated by short-range correlations, providing sufficient insight to model much of their impact on nuclear structure in neutron stars, and in low- to medium-energy scattering observables including neutrino oscillation measurements. These short-range correlations also appear to be related to the modification of the quark distributions in nuclei, and efforts to improve our understanding of the internal structure of these short-distance and high-momentum configurations in nuclei will provide important input on a wide range of high-energy observables.

   nucl-exnucl-thAnn.Rev.Nucl.Part.Sci.(2022)·62 citations
2. 02*

   Measurement of the ${}^1{S}_0$ neutron-neutron effective range in neutron-deuteron breakup

   R. C. Malone (1 and 2)🇺🇸 · A. S. Crowell (1 and 2) · L. C. Cumberbatch (1 and 2) · B. A. Fallin (1 and 2) · F. Q. L. Friesen (1 and 2)🇺🇸 · C. R. Howell (1 and 2)🇺🇸 · C. R. Malone (1 and 2) · D. R. Ticehurst (1 and 2) · W. Tornow (1 and 2)🇺🇸 · D. M. Markoff (2 and 3)🇺🇸 · B. J. Crowe (2 and 3) · H. Witała (4) ((1) Department of Physics, Duke University, Durham, NC, (2) Triangle Universities Nuclear Laboratory, Durham, NC, (3) Department of Mathematics and Physics, North Carolina Central University, Durham NC, (4) M. Smoluchowski Institute of Physics, Jagiellonian University, Krakòw, Poland)🇵🇱

   We report the most precise determination of the ${}^1{S}_0$ neutron-neutron effective range parameter ($r_{nn}$) from neutron-neutron quasifree scattering in neutron-deuteron breakup. The experiment setup utilized a collimated beam of 15.5 MeV neutrons and an array of eight neutron detectors positioned at angles sensitive to several quasifree scattering kinematic configurations. The two neutrons emitted from the breakup reaction were detected in coincidence and time-of-flight techniques were used to determine their energies. The beam-target luminosity was measured in-situ with the yields from neutron-deuteron elastic scattering. Rigorous Faddeev-type calculations using the CD Bonn nucleon-nucleon potential were fit to our cross-section data to determine the value of $r_{nn}$. The analysis was repeated using a semilocal momentum-space regularized N${}^4$LO${}^{+}$ chiral interaction potential. We obtained values of $r_{nn}=2.86\pm 0.01(stat)\pm 0.10(sys)$ fm and $r_{nn}=2.87\pm 0.01(stat)\pm 0.10(sys)$ fm using the CD Bonn and N${}^4$LO${}^{+}$ potentials, respectively. Our results are consistent with charge symmetry and previously reported values of $r_{nn}$.

   nucl-exPLB(2022)·5 citations
3. 03*

   Measurement of double-$\beta$ decay of ${}^{150}$Nd to the 0${}_1^{+}$ excited state of ${}^{150}$Sm in NEMO-3

   NEMO-3 Collaboration: X. Aguerre🇫🇷 · R. Arnold🇫🇷 · C. Augier🇫🇷 · A.S. Barabash🇷🇺 · A. Basharina-Freshville🇬🇧 · S. Blondel🇫🇷 · S. Blot🇬🇧 · M. Bongrand🇫🇷 · R. Breier🇸🇰 · V. Brudanin🇷🇺 · J. Busto🇫🇷 · A. Bystryakov🇺🇸 and 83 other authors

   The NEMO-3 results for the double-$\beta$ decay of ${}^{150}$Nd to the 0${}_1^{+}$ and 2${}_1^{+}$ excited states of ${}^{150}$Sm are reported. The data recorded during 5.25 yr with 36.6 g of the isotope ${}^{150}$Nd are used in the analysis. For the first time, the signal of the $2\nu \beta \beta$ transition to the 0${}_1^{+}$ excited state is detected with a statistical significance exceeding 5$\sigma$. The half-life is measured to be $T_{1/2}^{2\nu \beta \beta }(0_1^{+})=\left[1.11_{-0.14}^{+0.19}{\left(\text{mbox}stat\right)}_{-0.15}^{+0.17}\left(\text{mbox}syst\right)\right]\times 10^{20}\text{mbox}yr$. The limits are set on the $2\nu \beta \beta$ decay to the 2${}_1^{+}$ level and on the $0\nu \beta \beta$ decay to the 0${}_1^{+}$ and 2${}_1^{+}$ levels of ${}^{150}$Sm.

   nucl-exEPJC(2023)·10 citations
4. 04*

   The odderon discovery by the D0 and TOTEM collaborations

   Christophe Royon🇺🇸

   We describe the discovery of the colorless $C$-odd gluonic compound, the odderon, by the D0 and TOTEM Collaborations by comparing elastic differential cross sections measured in $pp$ and $p\bar{p}$ interactions at high energies.

   ↳ hep-exhep-phnucl-exRev.Mex.Fis.Suppl.(2022)·3 citations
5. 05*

   Seniority and $(\frac{9}{2}{)}^n$ configurations in neutron-rich Nickel isotopes

   S. Sidorov · D. Zhulyaeva · T. Tretyakova

   Excited states in low-energy spectra in ${}^{70-76}$Ni are considered. To this end, pairing forces in form of surface delta interaction are employed to account for formation of the ground state multiplet with seniority $\nu =2$ states. The multiplet splitting is described with mass relations of masses of neighbouring nuclei. Subsequently, seniority model is used to reproduce or predict the states $\nu =3$ in odd-even isotopes and $\nu =4$ in even-even isotopes. Correct account of $2_1^{+}$ state should allow for description of reversed order of states $J=4$ with $\nu =2$ and $\nu =4$ observed in experiment. The results obtained are compared with the structure of similar multiplets in $N=50$ isotones.

   ↳ nucl-thnucl-exCPC(2022)·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.