Thu·Jul 13, 2017Thursday·July 13, 2017

1. 01*

   A proton density bubble in the doubly magic ${}^{34}$Si nucleus

   A. Mutschler (1, 2)🇫🇷 · A. Lemasson (2, 3)🇫🇷 · O. Sorlin (2)🇫🇷 · D. Bazin (3)🇺🇸 · C. Borcea (4)🇷🇴 · R. Borcea (4)🇷🇴 · Z. Dombradi (5)🇭🇺 · J.P. Ebran🇫🇷 · A. Gade (3)🇺🇸 · H. Iwasaki (3)🇺🇸 · E. Khan (1)🇫🇷 · A. Lepailleur (2)🇫🇷 and 10 other authors

   Many properties of the atomic nucleus, such as vibrations, rotations and incompressibility, can be interpreted as due to a two component quantum liquid of protons and neutrons. Electron scattering measurements on stable nuclei demonstrate that their central densities are saturated, as for liquid drops. In exotic nuclei near the limits of mass and charge, with large imbalances in their proton and neutron numbers, the possibility of a depleted central density, or a 'bubble' structure, has been discussed in a recurrent manner since the 1970s. Here we report first experimental evidence that points to a depletion of the central density of protons in the short-lived nucleus 34Si. The proton-to-neutron density asymmetry in 34Si offers the possibility to place constraints on the density and isospin dependence of the spin--orbit force-on which nuclear models have disagreed for decades-and on its stabilizing effect towards limits of nuclear existence.

   nucl-exNat.Phys.(2017)·96 citations
2. 02*

   The Half-lives of ${}^{132}$La and ${}^{135}$La

   E. P. Abel · H. K. Clause · J. Fonslet · R. J. Nickles · G. W. Severin🇺🇸

   The half-lives of ${}^{135}$La and ${}^{132}$La were determined via gamma spectroscopy and high-precision ionization chamber measurements. The results are 18.930(6) h for ${}^{135}$La and 4.59(4) h for ${}^{132}$La compared to the previously compiled values of 19.5(2) h and 4.8(2) h, respectively. The new results represent an improvement in the precision and accuracy of both values. These lanthanum isotopes comprise a medically interesting system with positron emitter ${}^{132}$La and Auger electron emitter ${}^{135}$La forming a matched pair for internal diagnostics and therapeutics. The precise half-lives are necessary for proper evaluation of their value in medicine and for a more representative tabulation of nuclear data.

   nucl-exPRC(2018)·2 citations
3. 03*

   Hard processes in small systems

   Dennis V. Perepelitsa🇺🇸

   These proceedings from the Quark Matter 2017 conference give an overview of the latest experimental results on hard processes in small collision systems at RHIC and the LHC, discuss their implications, and consider several prospects for future measurements.

   nucl-exnucl-thNPA(2017)·1 citation

* 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.