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Abstract We measured the production cross sections and momentum distributions of proton-rich radioactive isotopes (RIs) whose atomic numbers were 18–37. These isotopes were produced by the projectile fragmentation of a 345-MeV/nucleon $$^{78}$$Kr beam impinged on a 5-mm Be target. The cross sections close to the stability region were reproduced fairly well by the semi-empirical formulas, EPAX3.1a and FRACS1.1. However, these formulas tend to overestimate the cross sections of the RIs near the proton drip line, sometimes by as much as 100-fold. The Abrasion–Ablation model in the LISE$$^{++}$$ package was employed, using different mass table variations, to describe the experimental results in this region. The best agreement was achieved when the Weizsäcker-Skyrme microscopic-macroscopic mass formula (WS4$$_{\mathrm{RBF}}$$) and a version of the nonrelativistic Hartree–Fock–Bogoliubov mass model (HFB22) were used. The momentum distribution was represented well by an asymmetric Gaussian distribution. The width of the high-momentum side of the distribution was reproduced fairly well by the Goldhaber model, whereas the width of the low-momentum side was 1.1 times larger than that of the high-momentum side. Moreover, an exponential-shaped low-momentum tail was observed, which began from a height of approximately 1/100–1/1000 of the momentum peak. The momentum means were not reproduced well by Morrissey’s empirical formula: additional velocity loss to the formula was observed. The yield of $$^{68}$$Br was smaller than the expected yield, as estimated from the yield systematics of its neighboring RIs. Assuming an in-flight decay in the separator, the half-life of $$^{68}$$Br was estimated to be $$105^{+62}_{-25}$$ ns. 

Conference Abstract 

Grain size distributions of 311 sediment samples from Sites U1450 and U1451 of International Ocean Discovery Program (IODP) Expedition 354 were determined using laser diffraction. Most of the samples were from turbidites, but some hemipelagic beds were also examined. The mean grain size values show that silt-sized particles are the dominant textural class, whereas the grain size values range from clay to coarse-grained sand. An overall upward change in mean grain size value reveals a slight coarsening-upward trend. However, other parameters such as standard deviation, skewness, and kurtosis show no systematic relationship with depth in the holes. The analyzed samples cover the age range from recent to early Miocene. Shepard textural classification plots show the sediments are mostly sandy silts, silty sands, and clayey silts with a few silts and sands also present. Frequency curve plots of samples from individual turbidite beds show inversely graded beds are most common at Site U1450, whereas thicker massive beds are dominant at Site U1451.