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A beam monitor is developed at the Rare-RI Ring storage ring facility at the RI beam factory at RIKEN. Because the Rare-RI Ring stores only a single exotic ion according to the operation principle, conventional beam instruments cannot be employed. In the present study, we design a simple monitoring system to confirm particle storage. The system comprises a thin foil and scintillators with photon sensors. When an ion passes through the foil, secondary electrons, including δ -rays, are emitted and are detected by a set of scintillation detectors without any guiding field. A beam test using 78 Ge with 175 MeV/nucleon successfully demonstrates the periodic revolution of the stored ions.

We investigated charge-changing processes (total charge-changing cross sections and partial charge-changing cross sections) for light proton-rich nuclei (34–36Ar, 33Cl, 25–28Si) at around 300A MeV on carbon and solid-hydrogen targets. We estimated the nuclear proton point radii of 33Cl and 25,26,27Si from the observed total charge-changing cross sections by using Glauber-model calculations with a phenomenological correction factor. Furthermore, we estimated the proton skin thickness for 33Cl coupled with its previously observed matter radius. From investigations of the partial charge-changing cross sections, clear zigzag pattern was observed for all isotopes. The present studies suggest that the pattern may be common in the proton-rich side, and depends on the odd–even nature of the fragment charge.

An electrostatic time-of-flight detector named E-MCP has been developed for quick diagnostics of circulating beam and timing measurement in mass spectrometry at the Rare-RI Ring in RIKEN. The E-MCP detector consists of a conversion foil, potential grids, and a microchannel plate. Secondary electrons are released from the surface of the foil when a heavy ion hits it. The electrons are accelerated and deflected by 90$^\circ$ toward the microchannel plate by electrostatic potentials. A thin carbon foil and a thin aluminum-coated mylar foil were used as conversion foils. We obtained time resolutions of 69(1) ps and 43(1) ps (standard deviation) for a $^{84}$Kr beam at an energy of 170 MeV/u when using the carbon and the aluminum-coated mylar foils, respectively. A detection efficiency of approximately 90% was obtained for both foils. The E-MCP detector equipped with the carbon foil was installed inside the Rare-RI Ring to confirm particle circulation within a demonstration experiment on mass measurements of nuclei around $^{78}$Ge produced by in-flight fission of uranium beam at the RI Beam Factory in RIKEN. Periodic time signals from circulating ions were clearly observed. Revolution times for $^{78}$Ge, $^{77}$Ga, and $^{76}$Zn were obtained. The results confirmed successful circulation of the short-lived nuclei inside the Rare-RI Ring.

We developed a time-of-flight (TOF) detector for mass measurements of rare radioactive isotopes (RIs) with a storage ring, called the Rare-RI Ring, in RIKEN. For successful mass measurements, a time resolution of less than 100 ps and a detection efficiency close to 100% are required. Additionally, the change of ion velocity in the detector should be as small as possible ( 1 0 − 4 ). To satisfy these requirements, the TOF detector utilizes ion-induced secondary electrons emitted from a thin foil and the crossed static electric and magnetic fields to transport the electrons isochronously to the microchannel plate detectors. The TOF detector was tested in both offline test with an alpha source and online test with heavy ions. In the online test with 84Kr ions of 200 MeV/nucleon, a time resolution of 38.6(2) ps in sigma and a position-averaged detection efficiency of 95.2(2)% were achieved in the entire area of 45-mm-diameter aluminum-coated Mylar foil. This good performance is attributed to the electromagnetic field achieved, which is the strongest thus far for a detector with this design.

We measured the energy dependence of the total reaction cross sections ( σ R ) for the proton drip-line nucleus of neon isotopes, 17Ne, with a solid hydrogen target. The σ R on a proton target in the low- and intermediate-energy regions were provided, where only a few values are available for unstable nuclei. The new data were compared with theoretical calculations using the Glauber model. In the low-energy region (∼100A MeV), the theoretical cross sections overestimate the experimental ones, whereas the theoretical ones significantly underestimate the experimental data in the intermediate energy region (∼300-500A MeV). We discuss several possibilities for solving this discrepancy. This work suggests the necessity of more careful investigations of the energy dependence of σ R for various nuclei on a proton target to determine the nuclear size properties precisely.

The present study summarizes the conductivity of the drop-cast film for various amine complexes of the novel self-doped polyanilines bearing phosphonic acid, poly(2-methoxyaniline-5-phosphonic acid) (PMAP) and poly(2-methoxyaniline-5-phosphonic acid monoethyl ester) (PMAPE). The conductivity was revealed to depend on the kind and amount of the amine base. The tendency of PMAP and PMAPE complexes was similar, but the PMAP ones exhibited the higher conductivity than the PMAPE ones. In the case of the pyridine and CF 3 CH 2 NH 2 complexes of PMAP, the conductivity more than 10 S m −1 was kept even in the presence of four equivalents of the amine based on the phosphonic acid moiety. The charge dissipation property of the PMAP/pyridine (1:2) complex was also investigated qualitatively by top-coating a resist on a quartz substrate in the electron beam lithography. The obtained pattern clearly showed the charge dissipation property. Use of PMAP/{CF 3 CH 2 NH 2 /NH 3 (4:1)} (1:3) complex made it possible with the development using only water in place of an aqueous NMe 4 OH solution.

Novel self-doped polyanilines bearing phosphonic acid, poly(2-methoxyaniline-5-phosphonic acid) (PMAP) and poly(2-methoxyaniline-5-phosphonic acid monoethyl ester) (PMAPE) were characterized in the following properties: (1) thermostability, (2) morphology in the solid state, (3) absorption and transparency in the spin-coating film, (4) delocalization of polaron, (5) doping efficiency, and (6) chemical oxidation and reduction. The UV–vis–NIR absorption spectra of the spin-coating films of PMAP/pyridine (1:2) and PMAPE/pyridine (1:1) show the polaron band and free carrier tail, which are characteristic to the conducting polymers. The highly transparent films of them (up to ∼90% transparency) were formed by spin-coating. Concerning the property of the polaron in the polymer, the ESR spectra suggest that polaron of PMAP/pyridine (1:2) is more delocalized than that of PMAPE/pyridine (1:1). The XPS experiments indicate that the doping efficiency of PMAP is much higher than that of PMAPE, which is likely to be due to diprotic acid units derived from phosphonic acid of PMAP. Oxidation and reduction of PMAP and PMAPE were demonstrated by treatment with the corresponding oxidant {(NH 4 ) 2 S 2 O 8 } and reductant (N 2 H 4 ·H 2 O), respectively.

We measured the reaction cross sections of the two-neutron halo nucleus 14Be with proton and carbon targets at about 41 and 76 MeV/nucleon. Based on a Glauber model calculation, we deduced the matter density distribution of 14Be in which previously measured interaction cross sections at relativistic energies were also included. An s-wave dominance in 14Be has been confirmed, although the halo tail of 14Be is not distributed as much as that of 11Li. Significant mixing of the p-wave in addition to the s- and d-wave is also suggested.

Poly(2-methoxyaniline-5-phosphonic acid monoethyl ester) (PMAPE) was synthesized via oxidative polymerization of 2-methoxyaniline-5-phosphonic acid monoethyl ester. This is the first example of the conducting self-doped polymers with phosphonic acid monoester. Self-doping of the polymer was shown by UV–vis–NIR and ESR measurements. The pyridinium salt of the thus-obtained PMAPE was water-soluble and its film exhibited conductivity.

An isochronous mass spectroscopy system using a newly constructed storage ring named the “rare-RI ring” is expected to be implemented at the RIKEN Nishina Center to determine the masses of short-lived rare nuclei including those in the r-process region with a relative precision of the order of 10 - 6 even for only one particle. In an isochronous storage ring, the mass is determined by measuring the revolution time of each nucleus. Our rare-RI ring consists of six magnetic sectors, and each sector consists of four bending magnets. To precisely optimize the isochronous conditions of the circulating particles for large acceptance, we install ten trim coils to half of the bending magnets. A fast-response and fast-charging kicker system enables selective and efficient injection of the produced rare nuclei into the ring one by one, along with facilitating efficient extraction of the circulating particles for time-of-flight measurement. Construction of the rare-RI ring was begun in the middle of the fiscal year 2012 at the RIKEN RI Beam Factory, and the ring is expected to be fully functional by 2015.

A large time-of-flight (TOF) detector has been developed for the Rare-RI Ring. This detector consists of a Multi Channel Plate (MCP) and a carbon foil. Secondary electrons from the carbon foil are transported to the MCP by crossed electric and magnetic fields. In order to cover the beam size of the ring, a large and thin carbon foil (100 mm × 50 mm2 and 60 μ g/cm2) is used as a sensitive material. The time resolution of σ ≈ 130 ps, the detection efficiency about 56% and a position dependence of the TOF about 1 ns are obtained. A calculated position dependence of TOF adopting experimental (inhomogeneous) electric field and a homogeneous magnetic field is in agreement with the experimental one. These results suggest that the homogeneity of electric field is important to improve the time resolution in the large size detector.

The in-flight particle separation capability of intermediate-energy radioactive ion (RI) beams produced at a fragment separator can be improved with the Cherenkov light detection technique. The cone angle of Cherenkov light emission varies as a function of beam velocity. This can be exploited as a velocity selector for secondary beams. Using heavy ion beams available at the HIMAC synchrotron facility, the Cherenkov light angular distribution was measured for several thin radiators with high refractive indices ( n = 1.9 ~ 2.1 ). A velocity resolution of ~10−3 was achieved for a 56Fe beam with an energy of 500 MeV/nucleon. Combined with the conventional rigidity selection technique coupled with energy-loss analysis, the present method will enable the efficient selection of an exotic species from huge amounts of various nuclides , such as uranium fission products at the BigRIPS fragment separator located at the RI Beam Factory.

As a self-doped conducting polyaniline bearing phosphonic acid, poly(2-methoxyaniline-5-phosphonic acid) (PMAP) was synthesized via oxidative polymerization of 2-methoxyaniline-5-phosphonic acid. The pyridinium salt of thus-obtained PMAP was water-soluble and its film exhibited conductivity.

The level structure of 30 P up to 8.25 MeV was investigated via in-beam γ -ray spectroscopy using the 28 Si( 3 He,p γ ) 30 P reaction at 9 MeV at the University of Tsukuba Tandem Accelerator Complex in Japan. An energy level scheme was deduced from γ - γ coincidence measurements. 47 new transitions have been observed from the previously known states (mostly resonances), thereby reducing the uncertainties in the excitation energies of 17 states from 3 to 10 keV to values of γ -ray angular distributions and γ - γ directional correlation of oriented nuclei (DCO ratios) were made for several observed levels of 30 P.

A thick and large solid hydrogen target (SHT) for radioisotope (RI) beams was developed. A target with 100 mm thickness and 50 mm diameter equipped with thin Kapton windows (25 μm) was achieved. We developed a new method to fill solid hydrogen into a large target cell by eliminating any void or porous regions. The expansion of thin Kapton windows and the real thickness of SHT were measured by a laser distance meter and an energy-loss of RI beams, respectively. They gave the same thickness confirming the complete solidification of hydrogen in the cell. We obtained a window expansion of about 2.5 mm (about 1.25 mm for each side).

A system for the spin-polarization measurement of unstable nuclei has been developed, in which the alternation of nuclear spins takes place by adiabatically rotating a holding magnetic field for the preservation of spin polarization, without applying a resonant oscillating magnetic field for NMR. The performance of the system was studied with spin-polarized 20F ( I π = 2 + , T 1 / 2 = 11.163 s) produced in the 19 F ( d → , p ) 20 → F reaction at E/A = 7 MeV at the RIKEN RIBF facility. In the measurement, the magnitude of 20F spin polarization | P ( 20 F ) | = 1.6 ( 2 ) % was successfully observed with the new system.

Objectives. This study sought to determine whether patients with sick sinus syndrome could be detected by analyzing the initial portion of the signal-averaged P wave corresponding to the electrical activity of the perinodal atrial myocardial cells.Background. In sick sinus syndrome, pathophysiologic abnormalities have been shown not only in the sinus node, but also in atrial muscle, especially the perinodal portion.Methods. The study included 41 patients with sick sinus syndrome and 140 age-matched control subjects. Eighteen of 41 patients with sick sinus syndrome had paroxysmal atrial fibrillation. Signal-averaged P wave electrocardiograms (ECGs) were recorded through a bandpass filter of 40 to 300 Hz with a P wave-triggering technique. Signals of the orthogonal bipolar leads were combined into a spatial magnitude. The root mean square voltage for the initial 30 ms (EP30) and the duration of initial low amplitude signals 22 ms as atrial early potential gave a sensitivity of 76%, a specificity of 91%, a positive predictive value of 74% and a negative predictive value of 93% for identification of patients with sick sinus syndrome.Conclusions. These results suggest that the long, low amplitude signals early in the filtered P wave on the signal-averaged ECGs are characteristic of sick sinus syndrome. Thus, the atrial early potential could be a useful marker to identify patients with sick sinus syndrome.

To determine whether the extent of myocardial fibrosis in dilated cardiomyopathy could be estimated noninvasively, signal-averaged electrocardiograms were recorded in 32 patients with dilated cardiomyopathy, followed by left ventricular endomyocardial biopsy. The root mean square voltage for the last 40 msec (V40), the duration of the filtered QRS complex (fQRSd) and the duration of low amplitude signals40 microV (LAS) were obtained by signal-averaged electrocardiography. The extent of fibrosis in all biopsy samples was measured by the point-counting method. The extent of myocardial fibrosis closely correlated with fQRSd (r = 0.623, p0.001), LAS (r = 0.570, p0.001), and V40 (r = -0.355, p0.05). When fibrosis was classified into intercellular and interfascicular types, the extent of intercellular fibrosis more closely correlated with fQRSd (r = 0.695, p0.0001), LAS (r = 0.640, p0.0001), and V40 (r = -0.533, p0.005). These results suggest that signal-averaged electrocardiograms might be useful for estimation of the extent of myocardial fibrosis, especially intercellular fibrosis in patients with dilated cardiomyopathy.

To clarify how the long-term β-blocker (β) therapy for the patients (pts) with dilated cardiomyopathy (DCM) improves the rate of freedom from cardiac death (RFCD), 57 DCM pts with β (metoprolol; 40–60 mg/day)(G-l, followup; 6–120 M) and 72 DCM pts without β (G-2, follow-up; 6–102 M) were followed up. The survival was confirmed by annual interview. The cause of death and the preterminal condition of the pts were obtained from family members, medical personnel or medical recordings. The RFCO was analyzed with Kaplan-Meier life table method. At entry, there were no significant differences in age, sex, blood pressure, heart rate, left ventricular end-diastolic dimension (64.0 ± 6.0 vs 63.5 ± 6.8 mm) and ejection fraction (40.7 ± 9.1 vs 42.3 ± 8.3%) measured by echocardiography, and the severity of ventricular arrhythmia by 24 hours Holter monitoring (according to the Lawn's grade) between G-l and G-2. During the follow-up period, non-cardiac death occurred in 2 pts in G-1 and in 3 pts in G-2. The annual RFCD were calculated as shown below; 1Y 2Y 3Y 4Y 5Y 6Y 7Y G-1 1.0 * 1.0 # 0.98 * 0.98 # 0.98 # 0.98 # 0.87 * G-1 0.91 0.86 0.84 0.84 0.72 0.62 0.62 * p l 0.05 # P l 0.01 vs G-2 The number of death from heart failure did not show significant difference between G-1 (3 of 57 pts) and G-2 (4 of 72 pts). On the other hand, sudden death has occurred more often in G-2 (10 of 72 pts) than in G-1 (1 of 57 pts) (p l 0.05), resulting in that the RFCD was significantly better in G-l than in G-2. These results indicate that the long-term β-blocker therapy for DCM might improve the rate of freedom from cardiac death due to prevention of sudden death rather than of death from heart failure.

In sick sinus syndrome (SSS), pathophysiological abnormalities have been shown not only in the sinus node but also in the atrial muscle, especially of the perinodal portion. To investigate whether the electrophysiological abnormalities of atrial muscle in SSS would induce the characteristic P wavepattern, especially in the initial portion of the P wave, we studied 37 patients with SSS and 67 age-comparable control patients. using the P wave-triggered signal-averaged electrocardiography. Sixteen of 37 SSS patients had paroxysmal atrial fibrillation (Paf). Signal-averaged electrocardiograms were recorded with a band-pass filter of 40–300 Hz and signals of 200 beats or more were averaged with the P wave-triggering technique. The P wave complexes of the three bipolar leads were combined into a spatial magnitude, and then the root mean square voltage for the initial 30 ms (EP30) and the last 20 m (LP20) of filtered P wave were measured. The duration (Ad) and root mean square voltage (RMS) of the total filtered P wave were also measured. Results SSS with Paf SSS without Pat Control EP30 (μV) 2.55 ± 1.17 * 2.16 ± 0.98 * 3.93 ± 1.23 LP20 (μV) 1.98 ± 0.40 # † 2.79 ± 1.04 3.35 ± 1.76 Ad (ms) 145.8 ± 16.1 * † 131.2 ± 14.1 $ 123.7 ± 11.7 RMS (μV) 6.20 ± 0.41 5.82 ± 0.82 6.20 ± 1.47 * p l 0.0001 # P l 0.005 $ p l 0.05 vs. Control † p l 0.01 vs SSS Without Pat The amplitude of initial portion of filtered P wave was significantly lower and the duration was longer in SSS patients with/without Paf than the controls, while there was no significant difference in the amplitude of the terminal portion between SSS patients without Paf and controls. The criteria of “EP30 ≤ 3.0 μV and Ad g 130 m” as defining “atrial early potential” gave a sensitivity of 76%, a specificity of 83% and a predictive accuracy of 81% for detection of patients with SSS. These results indicate that the low amplitude signals in the initial portion of filtered P wave were characteristic of SSS, so that the recognition of atrial early potential might be promising to identify patients with SSS.

In general, it is well known that the energy efficiency of a grinding process decreases with decrease in produced particle size, increase in grinding time, or increase in input energy. In this paper, a grinding method, based on fracture mechanics, to produce ultrafine particles has been investigated. We define the size reduction energy as the elastic strain energy which is stored in the specimen up to the instant of fracture. Assuming that the kinetic energy of a grinding medium or a particle were converted completely into fracture energy, the relationship between impact velocity required to fracture and particle size, or between impact velocity of a grinding medium required for a particle to fracture and mass of a medium have been calculated. As a result, the assumption that, for ultrafine grinding, a grinding medium collides against a particle was found to be more feasible than that a particle collides against a medium. It was necessary to increase the collision probability because the number of particles produced varies inversely as the cube of particle size. The experimental verification of the above considerations was performed using a ball mill. Ground products smaller than 3 μm with a median diameter of about 0.3 μm were obtained.