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Information concerning presentations at the 12th International Symposium on Electron Beam Ion Sources and Traps (EBIST) held in East Lansing, Michigan on May 18-21, 2014 is presented. It states there were four main sessions concerning developments of EBIST facilities, atomic spectroscopy of highly charged ions, and material and surface interactions with charged ions. It also included presentations on nuclear physics with storage rings, applications of highly charged ions, and spin qubits.

We review our recent high resolution experiments on photoabsorption by Fe14+ [M. C. Simon, et al., Phys. Rev. Lett. 105, 183001 (2010)], Fe15+, and Ar12+ [M. C. Simon, et al., J. Phys. B-At. Mol. Opt. Phys. 43, 065003 (2010)] at photon energies up to 1 keV. These ions play an essential role in photoionized astrophysical plasmas. Diagnostics of X-ray binary systems rely heavily on precise identification and knowledge of absorption lines. Novel experiments using an electron beam ion trap, FLASH EBIT, in combination with monochromatic synchrotron radiation allow us to investigate ions in charge states hitherto out of reach. Trapped ions can be prepared in any charge state at target densities sufficient to measure absorption cross sections below 0.1 Mb. This results in benchmark state-of-the-art predictions of the transitions wavelengths, widths, and absolute cross sections. [ABSTRACT FROM AUTHOR]

Decay studies of very neutron-deficient nuclei 43Cr and 48Ni with the application of a time projection chamber with optical readout are presented. [ABSTRACT FROM AUTHOR]

The investigation of the limits of nuclear existence is fundamental to the understanding of nuclear forces and structure. The limits of binding for very neutron-rich nuclei and the location of the neutron dripline are established experimentally only for the lightest elements. We report on the discovery of the new neutron-rich isotopes 40Mg, 42,43Al, and 44Si. These rare isotopes were produced at the National Superconducting Cyclotron Laboratory by fragmentation of a 141 MeV/u 48Ca beam on a tungsten target. The combination of the A1900 fragment separator together with the analysis beam line of the S800 spectrograph provided a two-stage fragment separation with exceptional selectivity. The observation of the odd-odd nucleus 42Al, which was predicted to be unbound by FRDM [1] and HFB-8 [2] models, is the first indication that the neutron drip line may be located significantly further towards heavier isotopes in this mass region than it is currently believed. [ABSTRACT FROM AUTHOR]

The decay properties of rp-process nuclei in the vicinity of 100Sn have been studied at the National Superconducting Cyclotron Laboratory (NSCL). The measured β-decay half-life for 100Sn is 0.55-0.31+0.70 s, in agreement with a previous measurement. In 98In, the β-decay of the ground state plus that of a long lived isomer were observed with half-lives of 47(13) ms and 0.66(40) s respectively. The half-life of 96Cd, measured for the first time, is 1.03-0.21+0.24 s; however, the existence of a predicted isomeric state in this nucleus could not be confirmed. Additionally, a gamma cascade de-exciting a μ-isomer in the odd-odd nucleus 96Ag was observed. The implications of the measured half-life of 96Cd on the calculated rp-process final abundances are discussed. [ABSTRACT FROM AUTHOR]

We explore the limits of nuclear stability and the consequences on nuclear structure theory by measuring masses of neutron-unbound nuclei and level energies above the neutron separation energy such as for the first excited state in 24O. Open problems in reaction theory are addressed by, among others, measurements of the Coulomb breakup of 8Li on a Pb and C target at 40 and 70 MeV/u. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

One-nucleon removal reactions at relativistic energies have been used as spectroscopic tool to obtain information about the ground state properties of several neutron-rich isotopes in the sd-shell. Using the FRS at GSI, the longitudinal momentum distributions of the emerging fragments after one-nucleon removal cross-sections were measured. The relative contributions of the remaining fragments in their ground and excited states have been determined from measurements of γ rays in coincidence with the longitudinal momentum distributions. The interesting case of 23O will be directly address. The interpretation of our experimental results in the framework of a simple theoretical model will favours a spin and parity assignment of 1/2+ for the 23O ground state in agreement with shell model predictions. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

The availability of fast radioactive beams offers the possibility for studies of E1-strength in projectiles via Coulomb excitation. Theoretical calculations predict that a significant fraction of this strength is shifted towards lower excitation energies in neutron-rich systems (e.g., [1]). At the NSCL, virtual photon scattering was used to probe the discrete structure of both [sup 18]O and [sup 20]O for levels in the region between 1 and 8 MeV. Two 1[sup -] levels at 5.35(10) and 6.85(5) MeV were observed for the first time in [sup 20]O [2]. The observed γ-ray spectrum for [sup 20]O is, in fact, dominated by transitions resulting from E1 excitations to these states. The extracted B(E1) ↑ values of ∼0.062(16) e²fm² and ∼0.035(9) e&sup22fm² for the 5.35 and 6.85 MeV levels, respectively, are larger than shell model calculations predict [3, 4]. Such large dipole strengths are not observed for low-lying 1[sup -] states in [sup 18]O, indicating a shift of dipole strength towards lower energies as one approaches the neutron drip-line. [ABSTRACT FROM AUTHOR]

One-nucleon removal reactions at relativistic energies have been used as spectroscopic tool to obtain information about the ground state properties of [sup 8]B and [sup 23]O. Using the FRS at GSI, the longitudinal momentum distributions of the emerging fragments after breakup and the one-nucleon removal cross-sections were measured. The relative contributions of the remaining fragments ([sup 7]Be and [sup 22]O) in their ground and excited states have been determined from measurements of γ rays in coincidence with the longitudinal momentum distributions. In the [sup 8]B case, the experimental breakup data on two different targets (C and Pb) allow a determination of the weight of the [sup 7]Be[sup *] component in the [sup 8]B ground state wave function as (13.3±2.2) %. These results are discussed in the context of a theoretical three-body model. Preliminary results on [sup 23]O indicate a spin and parity assignment of ½[sup +] in agreement with shell model predictions. [ABSTRACT FROM AUTHOR]

The upgrade of the National Superconducting Cyclotron Laboratory (NSCL) is well under way and nearing completion. With the coupled superconducting cyclotrons K500 and K1200, the NSCL will be able to deliver high-intensity heavy-ion beams for nuclear reaction studies at intermediate energies and for the production of rare isotope beams via projectile fragmentation. I am reporting on the planned facility and the current status of the upgrade project. Selected highlights of the physics opportunities at the upgraded facility are reviewed. Specific advantages of using fast beams for rare isotopes will be discussed. [ABSTRACT FROM AUTHOR]