Thu·Jan 3, 2019Thursday·January 3, 2019

1. 01*

   First observation of 20B and 21B

   S. Leblond🇫🇷 · F.M. Marqués🇫🇷 · J. Gibelin🇫🇷 · N.A. Orr🇫🇷 · Y. Kondo🇯🇵 · T. Nakamura🇯🇵 · J. Bonnard🇫🇷 · N. Michel🇺🇸 · N.L. Achouri🇫🇷 · T. Aumann🇩🇪 · H. Baba🇯🇵 · F. Delaunay🇫🇷 and 36 other authors

   The most neutron-rich boron isotopes 20B and 21B have been observed for the first time following proton removal from 22N and 22C at energies around 230 MeV/nucleon. Both nuclei were found to exist as resonances which were detected through their decay into 19B and one or two neutrons. Two-proton removal from 22N populated a prominent resonance-like structure in 20B at around 2.5 MeV above the one-neutron decay threshold, which is interpreted as arising from the closely spaced 1-,2- ground-state doublet predicted by the shell model. In the case of proton removal from 22C, the 19B plus one- and two-neutron channels were consistent with the population of a resonance in 21B 2.47+-0.19 MeV above the two-neutron decay threshold, which is found to exhibit direct two-neutron decay. The ground-state mass excesses determined for 20,21B are found to be in agreement with mass surface extrapolations derived within the latest atomic-mass evaluations.

   nucl-exnucl-thPRL(2018)·33 citations
2. 02*

   Simulations of radiation damage in spacecraft camera for ESA JUICE mission

   Hualin Xiao🇨🇭 · Wojtek Hajdas🇨🇭 · Stephane Beauvivre · Daniel Kraehenbuehl · Ruth Ziethe · Nikhil Banerji

   The JUpiter ICy moons Explorer (JUICE) is an ESA interplanetary spacecraft being developed to perform detailed investigations of the Jupiter system and three of its icy moons: Europa, Callisto and Ganymede. The emphasis will be given on Ganymede as a small planetary body to be studied as a potential habitat. The spacecraft is set for launch in 2022 and would reach Jupiter in 2030. Two identical optical cameras are proposed for the mission to monitor the spacecraft and its surroundings. The sensors of the cameras need to be protected from hazardous radiation levels caused by extremely high fluxes of very energetic electrons. A precise model of the camera was developed to be used for intense Monte Carlo simulations performed to optimize the shielding and to determine the radiation damage during the mission. Simulations included determination of the total ionizing and non-ionizing doses in the sensors and crucial electronic components. This paper presents both simulation methods and results.

   ↳ physics.space-phastro-ph.IMnucl-exphysics.geo-ph+10 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.