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Very neutron-deficient fragments were produced by projectile fragmentation of a 140 MeV/ nucleon 78Kr primary beam on a beryllium target. The secondary fragments were unambiguously identified after separation in the A1900 fragment separator. Three events of 60Ge and four events of 64Se have been observed for the first time, making 60Ge the heaviest known isotone of the N = 28 neutron shell. No events of 59Ga and 63As have been observed providing very strong evidence that these nuclei are unbound with respect to proton emission. [ABSTRACT FROM AUTHOR]

The ground state of 11Li is the preeminent example of a two-neutron-halo nucleus and is part of an isobaric sextet. Another member of this sextet, the double isobaric analog of 11Lig.s. in 11B, has been identified in the 12Be(p, 2n)11B reaction. The state was discovered through its two-proton decay branch. From detected 2p + 9Li events, its excitation energy was determined to be 33.57(8) MeV using the invariant mass method. With the known masses of 11Li and its isobaric analog state in 11Be, three members of the same sextet have measured masses for the first time, permitting the masses of the remaining members to be extrapolated using the isobaric multiplet mass equation. All members of this multiplet are expected to have a two-nucleon halo structure and this was found consistent with the evolution of the mass across the sextet. The momentum correlations of the detected protons were found to have both "diproton" and "cigar" components. [ABSTRACT FROM AUTHOR]

One-proton removal reactions of 936 MeV/u 8B have been studied with carbon and lead as breakup targets. Using the FRS at GSI, the longitudinal momentum distributions of the 7Be fragments and the one-proton removal cross section of 8B were measured. The relative contributions of the breakup channels leading to 7Be in its ground state and excited state at 429 keV (7Be*) have been determined from measurements of γ rays in coincidence with the fragments from the one-proton removal reaction. The experimental breakup data are discussed in the context of a theoretical (α+3He+p) three-body model. The combined data from the two targets allow a determination of the weight of the 7Be* component in the 8B ground state wave function as (13.3±2.2%) [Copyright &y& Elsevier]

Laser-plasma interactions in the novel regime of relativistically induced transparency (RIT) have been harnessed to generate intense ion beams efficiently with average energies exceeding 10 MeV/nucleon (>100 MeV for protons) at "table-top" scales in experiments at the LANL Trident Laser. By further optimization of the laser and target, the RIT regime has been extended into a self-organized plasma mode. This mode yields an ion beam with much narrower energy spread while maintaining high ion energy and conversion efficiency. This mode involves self-generation of persistent high magnetic fields (∼10 4  T, according to particle-in-cell simulations of the experiments) at the rear-side of the plasma. These magnetic fields trap the laser-heated multi-MeV electrons, which generate a high localized electrostatic field (∼0.1 T V/m). After the laser exits the plasma, this electric field acts on a highly structured ion-beam distribution in phase space to reduce the energy spread, thus separating acceleration and energy-spread reduction. Thus, ion beams with narrow energy peaks at up to 18 MeV/nucleon are generated reproducibly with high efficiency (≈5%). The experimental demonstration has been done with 0.12 PW, high-contrast, 0.6 ps Gaussian 1.053  μ m laser pulses irradiating planar foils up to 250 nm thick at 2-8 × 10 20  W/cm 2 . These ion beams with co-propagating electrons have been used on Trident for uniform volumetric isochoric heating to generate and study warm-dense matter at high densities. These beam plasmas have been directed also at a thick Ta disk to generate a directed, intense point-like Bremsstrahlung source of photons peaked at ∼2 MeV and used it for point projection radiography of thick high density objects. In addition, prior work on the intense neutron beam driven by an intense deuterium beam generated in the RIT regime has been extended. Neutron spectral control by means of a flexible converter-disk design has been demonstrated, and the neutron beam has been used for point-projection imaging of thick objects. The plans and prospects for further improvements and applications are also discussed.

We report on the first direct measurement of the proton separation energy for the proton-unbound nucleus (69)Br. Bypassing the (68)Se waiting point in the rp process is directly related to the 2p-capture rate through (69)Br, which depends exponentially on the proton separation energy. We find a proton separation energy for (69)Br of Sp((69)Br )= -785(-40)(+34) keV; this is less bound compared to previous predictions which have relied on uncertain theoretical calculations. The influence of the extracted proton separation energy on the rp process occurring in type I x-ray bursts is examined within the context of a one-zone burst model.

The aim of this study was to compare transiently evoked otoacoustic emissions (TEOAE) and pure tone audiometry in normal hearing ears and ears with cochlear hearing loss (60 ears of 30 subjects), to obtain defined data on qualitative and quantitative correlations. We wanted to determine the reliability with which a clinical examiner could predict a typical, idealized audiometric configuration from TEOAE measurements. The results show that the presence of otoacoustic emissions drops as a function of hearing loss and that there is a highly statistically significant correlation between characteristics of otoacoustic emission (coefficient of correlation and strength of otoacoustic emissions) and hearing loss at 1000-3000 Hz frequency. Otoacoustic emissions are never found when hearing loss at 1000-3000 Hz exceeds 36 dBnHL. The main practical conclusion is that otoacoustic emission presence indicates middle frequency functional integrity of the outer hair cells of Corti's organ. Absence of otoacoustic emissions is harder to interpret and requires further audiological diagnosis (brain-stem auditory evoked potentials).