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This paper reports on the 1H(28Ne,28Ne) and 1H(28Ne,27Ne) reactions studied at intermediate energy using a liquid hydrogen target. From the cross section populating the first 2+excited state of 28Ne, and using the previously determined B(E2) value, the neutron quadrupole transition matrix element has been calculated to be Mn=13.8 ±3.7 fm2. In the neutron knock-out reaction, two low-lying excited states were populated in 27Ne. Only one of them can be interpreted by the sd shell model while the additional state may intrude from the fp shell. These experimental observations are consistent with the presence of fp shell configurations at low excitation energy in 27,28Ne nuclei caused by a vanishing N=20 shell gap at Z=10.

Control of the beam position for three-dimensional pencil-beam scanning is important because the position accuracy of the beam significantly impacts the alignment of the irradiation field. To suppress this effect, we have developed a simple procedure for beamline tuning. At first, beamline tuning is performed with steering magnets and fluorescent screen monitors to converge the beam’s trajectory to a central orbit. Misalignment between the beam’s position and the reference axis is checked by using the verification system, which consists of a screen monitor and an acrylic phantom. If the beam position deviates from the reference axis, two pairs of steering magnets, which are placed on downstream of the beam transport line, will be corrected. These adjustments are iterated until the deviations for eleven energies of the beam are within 0.5 mm of the reference axis. To demonstrate the success of our procedure, we used our procedure to perform beam commissioning at the Kanagawa Cancer Center.

A two-dimensional dosimetry system was developed for the quality assurance (QA) of therapeutic scanned ion beams at Heavy Ion Medical Accelerator in Chiba (HIMAC). This system consists of a fluorescent screen and a charge-coupled device (CCD) camera. To evaluate the performance of this system, we carried out a few experiments concerning QA procedures. A verification of this system was also carried out by comparing the film dosimetry and the ionization chamber array. Also, we verified several types of corrections for errors, e.g., background and vignetting, that distort the measurement results. As a result, we confirmed that this system could be used for QA procedures of the therapeutic scanned ion beams.

A two-dimensional (2D) beam imaging system with a fluorescent intensifying screen and high-speed charge-coupled device (CCD) camera was developed to observe the fluctuations of the beam position and size. This system can perform imaging of the beam spot and the calculation of both its position and size from the obtained image with a cycle-time of 20 ms. For quality assurance of scanned carbon-ion therapy, we measured the stability of the unscanned-beam position and size by using this system at the isocenter in a treatment room. We confirmed that the fluctuation ranges of its position and size were less than the tolerance for scanning irradiation.

Abstract: Two-proton relative momentum distributions from the break-up channels 23Al→p+p+21Na and 22Mg→p+p+20Ne at an energy of 60–70 A MeV have been measured together with two-proton opening angles at the projectile fragment separator beamline (RIPS) in the RIKEN Ring Cyclotron Facility. The results demonstrate the existence of diproton emission component from single-step 2He for highly excited 23Al and 22Mg.

Abstract.: This paper reports on the 1H(28Ne,28Ne) and 1H(28Ne,27Ne) reactions studied at intermediate energy using a liquid hydrogen target. From the cross section populating the first 2+ excited state of 28Ne, and using the previously determined B(E2) value, the neutron quadrupole transition matrix element has been calculated to be Mn=13.8 ±3.7 fm2. In the neutron knock-out reaction, two low-lying excited states were populated in 27Ne. Only one of them can be interpreted by the sd shell model while the additional state may intrude from the fp shell. These experimental observations are consistent with the presence of fp shell configurations at low excitation energy in 27,28Ne nuclei caused by a vanishing N=20 shell gap at Z=10.

This paper reports on the 1H(28Ne,28Ne) and 1H(28Ne,27Ne) reactions studied at intermediate energy using a liquid hydrogen target. From the cross section populating the first 2+excited state of 28Ne, and using the previously determined B(E2) value, the neutron quadrupole transition matrix element has been calculated to be Mn=13.8 ?3.7?fm2. In the neutron knock-out reaction, two low-lying excited states were populated in 27Ne. Only one of them can be interpreted by the sd shell model while the additional state may intrude from the fp shell. These experimental observations are consistent with the presence of fp shell configurations at low excitation energy in 27,28Ne nuclei caused by a vanishing N=20 shell gap at Z=10.

By taking advantage of the high efficiency of the Coulomb dissociation method, we studied the stellar 22Mg(p, γ)23Al reaction. The radiative width Γγ of the first excited state in 23Al was determined by measuring the intermediate-energy 23Al → 22Mg + p breakup process with a lead target.

The evidence that some older patients with essential hypertension have low urinary dopamine excretion has brought into question the levels of urinary dopamine and plasma dopa, the major source of urinary dopamine, in young patients with essential hypertension. Twentyfour-hour urine sodium, creatinine, dopamine and noradrenaline and plasma dopa were evaluated in 48 patients with essential hypertension aged 18 to 27 years and 25 normotensive subjects. In comparison with age-matched normotensive subjects, the hypertensive patients had higher urinary dopamine (1920 ± 80 vs 1520 ± 130 nmol/day, p < 0.01) and noradrenaline (216 ± 11 vs 179 ± 12 nmol/day, p < 0.05) excretion. There was a significant correlation between urinary dopamine and noradrenaline excretion. There was no difference in plasma dopa levels between normotensive and hypertensive subjects. These results suggest that the elevated conversion of dopa to dopamine in the kidney is leading to increased urinary dopamine excretion in young patients with essential hypertension.