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Recent progress in advanced autonomous driving techniques, such as level 5 or level 4, requires precise dead reckoning in order to compensate main positioning systems such as GNSS, visual SLAMs or LIDARs. This kind of precise dead reckoning is established by using a gyroscope of 0.1 deg/ hr. class. Currently, gyroscopes that satisfy this accuracy include Fiber Optic Gyros (FOGs) and Ring Laser Gyros (RLGs) and their price range is more than $10,000 per axis. So it is strongly required to reduce the price of gyroscopes with equivalent accuracy for practical application and commercialization of autonomous driving. In order to respond these requirements, we have established price down scheme for fabrication of interferometric Fiber Optical Gyroscope (iFOG). The i-FOG is a sensor that detects the rotation speed of the object from the optical interference phase difference caused by the light relativistic effect (so-called Sagnac effect of light). Light incident from both ends of the optical path inside the optical fiber coil interferes with a phase difference proportional to the rotation speed of the optical path, so the rotation speed is detected by measuring this interference phase difference. To have precise optical phase difference, which comes only from actual input rotation speed i.e. without unwanted phase difference error comes from other than actual input rotation, we should use precisely aligned quadrupole optical fiber coil and modulation element parts, called IOC (Integrated Optical Circuit). The former contributes to reduce thermally induced optical phase difference, so-called Shupe effect, and the later contributes to reject unwanted polarization crosstalk which result in optical phase change by its excellent polarization rejection ratio. When considering fabrication cost of the i-FOG, production costs of these two important components have substantial ratio in total production cost. Especially the former one generally thought to be very difficult to reduce because it depends upon human hand-work to achieve quadrupole winding arrangement and precise alignment of optical fiber on the coil bobbin simultaneously. To solve this difficulty, we have developed automatic optical fiber winding machine which can execute automatic quadrupole winding with fine alignment of optical fiber by adopting double-flyer winding mechanism. This mechanism allow us to avoid extra and time consuming hand work for changing the optical fiber source from left to right and right to left for each layer of the fiber coil. This has reduced the man-time to 1/5. By combination of this technique and our fabrication process of IOCs, we have acquired the potential to reduce fabrication cost of i-FOGs.

We have developed a position-sensitive Parallel Plate Avalanche Counter (PPAC), which has been used as a focal plane detector in the BigRIPS fragment separator and the subsequent RI-beam delivery lines at the RIKEN Nishina Center RI Beam Factory. The PPAC detector plays an important role not only in the tuning of the separator and delivery lines but also in the particle identification of rare isotope (RI) beams. The PPAC detector has a sensitive area of 240 mm × 150 mm, and the position information is obtained by a delay-line readout method. Being called double PPAC, it is composed of two full PPACs, each measuring the particle locus in two dimensions. High detection efficiency has been made possible by the twofold measurement using the double PPAC detector. The sensitivity uniformity is also found to be excellent. The root-mean-square position resolution is measured to be 0.25 mm using an α source, while the position linearity is as good as ±0.1 mm for the detector size of 240 mm. Characteristics, operating principles, specifications, performance and issues of the PPAC detector are presented, including its signal transmission system using optical fiber cables.

The image quality of high-definition television (HDTV) cameras and camcorders for space activity is degraded by the presence of permanent bright pixels (so-called “white defects”) due to space radiation. We studied the space radiation damage to HDTV charge-coupled devices (CCDs; 2 × 106 pixels per chip) loaded in the Russian service module (SM) of the International Space Station (ISS) for 71 days, 256 days and 446 days. We used the “Passive Dosimeter for Lifescience Experiments in Space” (PADLES), which consists of CR-39 plastic nuclear track detectors (PNTDs) and thermoluminescent dosimeters, to measure space radiation doses received by the HDTV CCDs in the SM during loading periods. The average production rates of white defects for output voltage greater than 0.5 mV were 2.366 ± 0.055 pixels/day in Si and 5.213 ± 0.071 pixels/mGy in Si. We also investigated the correlation between the position of the white defects and tracks of high-energy particles with LET∞,Si of approximately 300 keV/μm or more using stacks of CR-39 PNTDs and the HDTV CCD chips. We found that approximately 30% of these high-energy high-LET particles coincided with the position of white defects on the HDTV CCDs in the SM.

A PAssive Dosimeter for Life-science Experiments in Space (PADLES) has been developed for measuring total absorbed dose and dose equivalents in the radiation environments of the International Space Station (ISS) where the Linear Energy Transfer (LET) of radiation ranges from 0.2 (ionization minimum) to 103 keVμm−1 or more. PADLES consists of two types of passive and integrating radiation detectors: MSO-S (Mg2SiO4:Tb) ThermoLuminescence Dosimeters (TLDs) and antioxidant-doped CR-39 plastic nuclear track detectors. In this paper, we first describe a method to obtain a water-equivalent absorbed dose by combining data from these two types of detector. In order to increase the reliability of PADLES for ISS space radiation dosimetry, we investigated the following characteristics of MSO-S TLDs: calibration of our ThermoLuminescence (TL) readout system for high-energy protons and gamma rays from 60Co and 137Cs sources; dose responses for high-energy heavy ions (He, C, Si, Ar, Fe); response variation of different manufacture batches; directional response for the high-energy protons; the initial variations and long-term fading effects of the TL response for high-energy protons and heavy ions at temperatures from −80 °C to 60 °C; and LET response.

An electro-conjugate fluid (ECF) is a kind of dielectric fluid that works as a functional/smart fluid generating a powerful jet flow (ECF jet) when subjected to a high d.c. voltage. The authors previously proposed the first liquid rate gyroscope in the world using ECF. The ECF liquid rate gyroscope proposed uses the drift of the ECF jet due to the Coriolis force when an angular motion is applied. The contribution of the proposed concept to gyroscope technology is that it provides the possibility of a low-cost micro gyroscope with inherent robustness to external impact. To move beyond a mere laboratory curiosity, the present paper describes the practical design of an ECF liquid rate gyroscope and characterizes the prototype. The ECF liquid rate gyroscope developed in this study has a scale factor, range of detection, resolution, and linearity of 32 mV/(°/s), ±400°/s, 0.04°/s, and 2 per cent of full scale (with a range of ±60°/s), respectively. These results show that the ECF liquid rate gyroscope could possibly become the next generation standard of micro gyroscopes.

An experiment to the search for very neutron-rich nuclei has been performed at RIKEN, using projectile fragmentation of an intense 64 A MeV 48Ca beam and the fragment separator RIPS. Three new neutron-rich isotopes, 34Ne, 37Na and 43Si were observed unambiguously for the first time, and convincing evidence for the particle instability of three others, 33Ne, 36Na and 39Mg was obtained. The experimental findings are discussed in comparison with recent theoretical predictions.

A new method to obtain the three-dimensional information on nuclear tracks was developed using color photography. Commercial color films were irradiated with ion beam and color-developed. The ion tracks were represented with color images in which different depths were indicated by different colors, and the three-dimensional information was obtained from color changes. Details of this method are reported, and advantages and limitations are discussed in comparison with a conventional method using a nuclear emulsion.

We have developed a delay-line parallel-plate avalanche counter (PPAC) with high detection efficiency for high-energy light ions. A large signal-to-noise ratio was achieved by a newly designed pre-amplifier and the usage of C3F8 gas at a pressure of 30 Torr . The counter has been tested with beams of 90 A MeV 7 Li at RIKEN, 340 A MeV 12 C at GSI, and 254 A MeV 8 B at GSI. We achieved high detection efficiencies (>95%) for all of these ions. Furthermore, we achieved reasonable position and timing resolutions.

The asymptotic normalization coefficients for the virtual decay 9 C → 8 B + p have been determined by measuring the crosssection of the 8 B(d, n) 9 C reaction in inverse kinematics at 14.4 MeV/u, using the RIPS facility. The deduced astrophysical S factor S18 of the 8 B(p ,γ ) 9 C capture reaction in the center of mass energy range 1–100 keV is S18 = 45 ± 13 eV b.  2001

The half-life of 44 Ti has been determined with a method measuring the activity of 44 Ti produced and implanted in a plastic plate through the projectile fragmentation. The half-life was determined from the specific activity of implanted 44 Ti nuclei determined through absolute measurements of the amount by counting fragments, and of their activity by taking ratios of sum- and single-peaks in high-resolution γ -ray spectra with a Ge detector. The half-life of 44 Ti determined was 59±2 years.

We present a new approach for performing numerical simulations of optical feedback semiconductor lasers for moving targets. The derived rate equation for the complex electric field is suitable for the numerical analysis of the dynamics in a self-mixing semiconductor laser with a Doppler frequency shift. We present numerical examples calculated using the rate equations.

The neutron drip line up to fluorine has been investigated by the projectile fragmentation of a 94.1A MeV 40 Ar beam at the fragment separator RIPS at RIKEN. A new neutron-rich isotope, 31 F, has been observed for the first time while clear evidence for the particle instability of 24,25 N, 27,28 O and 30 F has been obtained. The sudden change in stability from oxygen to fluorine may demonstrate the onset of deformation for the neutron-rich fluorine isotopes.

The fusion of 9,11 Li ( E = 11.2–15.2A MeV) with Si targets has been investigated in an inclusive approach. The neutron spectra in the energy range 0.5–22.5 MeV, corresponding to 9 Li and 11 Li projectiles, have been measured with the aid of the RIKEN “long neutron wall”. In the case of 9 Li, the neutron spectrum is in good agreement with the Monte Carlo calculated fusion-evaporation spectrum. In the case of 11 Li, the neutron spectrum is showing that an important number of fusions (33 ± 10) %, are preceded by the pre-emission of one or two halo neutrons.

We report on the first production and identification of two neutron-rich nuclei {sup 31}Ne and {sup 37}Mg. They were produced in the projectile fragmentation of an 80{ital A} MeV {sup 50}Ti beam on a {sup 181}Ta target, and were efficiently analyzed and identified through the fragment separator RIPS at RIKEN, by measuring the magnetic rigidity, time of flight, energy loss, and total kinetic energy. The particle stability of the new isotopes is discussed in comparison with various mass predictions. {copyright} {ital 1996 The American Physical Society.}

Experimental studies of neutron rich nuclei 8 He, 10 He, 12 Be and 13 Be have been performed using radioactive beams.

A new experimental technique utilizing a high-spin isomer beam (HSIB) has been developed. The HSIB of 174Hf was produced by the 9Be(170Er, 5n)174Hf reaction in inverse kinematics. By using the HSIB, the Coulomb excitation of the Kπ = 8− isomer in 174Hf was measured. The γ-rays from the 9− level, which is the first excited state built on the isomer, were observed as well as the cascade γ-rays of the ground-state rotational band. From the measured γ-ray yield, a value of 2 ± 1 e2b2 was extracted for the B(E2: 8− → 9−). This is the first experiment of γ-ray spectroscopy by means of the HSIB-induced secondary reactions.

We have studied 12 Be + p elastic and inelastic scattering and observed new levels of 12 Be at E 12 Be ∗ = 8.6, 10 and ∼ 14 MeV in the vicinity of He-emission thresholds, which can be candidates for states having an exotic cluster structure with He-like subsystems. Some new states were tentatively assigned to 13 Be in studies of the d( 12 Be, p) reaction.

The charge-state distributions and production cross sections of Ne recoil ions produced through pure ionization, electron capture, and electron loss processes of projectile Ar ions have been determined for 1.05-MeV/amu ${\mathrm{Ar}}^{\mathrm{q}+}$+Ne (q=4, 6, 8, 10, 12, 14, and 16) collisions using a projectile-ion-recoil-ion coincidence technique. Recoil ions in low charge states, in particular, singly charged ions, are produced predominantly through pure ionization without any change of projectile charge. Electron loss or capture processes of projectiles, though weak relative to the pure ionization, are found to result in an enhancement of the multiply charged recoil ions. The average charge 〈i${\mathrm{〉}}_{\mathrm{q},\mathrm{q}\ensuremath{'}}$ of recoil ions in a specific process, ${\mathrm{Ar}}^{\mathrm{q}+}$+Ne\ensuremath{\rightarrow}${\mathrm{Ar}}^{\mathrm{q}\ensuremath{'}+}$+${\mathrm{Ne}}^{\mathrm{i}+}$, is found to increase with increasing projectile charge q and with the number of the lost or capture electrons from or into projectiles.

The reactions 11 Li + CD 2 → 10 He + X and 11 Li + C → 10 He + X at a beam energy of 61A MeV have been studied by measuring the triple coincidence of 8He and two neutrons. Experimental data show a peak that can be explained as a resonance 10He, which is unbound by 1.2±0.3 MeV and its width is less than 1.2 MeV. Theinvariant mass spectra of 8He+n show a peak that is consistent with the decay 10 He → 8 He + n + n .

An experimental study of 8He + p elastic scattering and a search for 8He∗ as observed in two independent experimental methods. The obtained parameters of the excited state are E 8 He ∗ = 3.57±0.12 MeV , Γ =0.5±0.35 MeV, Γ 4 He+4n /Γ 6 He+n+n ⩽ 5% . Angular distributions for elastic and inelastic scattering are measured. The inelastic angular distribution is consistent with Jπ = 2+ for 8He3.55∗.

Yrast traps were found in N=83 isotones, 144Pm and 145Sm, by using inverse kinematic reactions, 14N(136Xe, 6n)144Pm and 16O(136Xe, 7n)145Sm. Their probable spin-parities are (27+) and (492+), respectively. Excitation energies of these isomers are 7.5 and 8.7 MeV Reaction products were transported by a gas filled recoil ion separation system and collected at 6 m down stream of the primary target position . The possible utilization of these high-spin isomers as secondary beams are discussed.

Proton elastic scatterings of neutron rich nuclei 9 Li and 11 Li have been measured for the first time at E lab / A =60 and 62 MeV, respectively, under the inverse kinematical conditions. While the angular distribution of 9 Li scattering follows the systematic trend from those of 6 Li and 7 Li scatterings, the 11 Li cross section is smaller by about a factor of two. Optical model calculations show that considerable changes in both real and imaginary potentials are necessary to reproduce the 11 Li data.

Multiply-charged secondary ions produced from condensed gas targets have been observed under energetic, heavy-ion impact. It is found that, though strongly suppressed over gaseous target collisions, multiply-charged ions are more efficiently extracted from condensed surfaces if molecules such as N2, O2, C2H2 are used as targets, compared with condensed rare-gas atom and other molecule (for example, CH4) gas targets. This feature could be understood qualitatively as being due to their large initial kinetic energy provided through Coulomb explosion of multiply-charged molecular ions originally produced in heavy-ion collisions.

We have measured the target thickness dependence ofK-vacancy production probabilities and total cross sections for 40.6 MeV Ar ions hitting Ca and Cu targets. The probabilities were measured as a function of the scattering angle between 0.13° and 1.4° by means of aK x-ray-particle coincidence. By integrating the measured probabilities over the impact parameter a significantly lower total cross section was obtained than the directly measured value. The maximum seen in the impact parameter dependent probability varies with decreasing target thickness towards the results obtained with molecular and atomic gas targets. From these observations a multiple collisionL-vacancy process prior to 2pπ-2pσ rational coupling is concluded.

Reaction cross sections (σR) and fragmentation cross sections (σF) of reactions of a 11Be beam on C, Al targets were measured by a transmission method at 33A MeV. The σR have been determined to be 1.56±0.03 b for 11 Be + 12 C , and 2.27±0.05 b for 11 Be + 27 Al . These values are extremely large compared with the systematics of stable nuclei. A large σF has also been observed for the 11Be→10Be channel. Model calculations using present and 790A MeV data confirm the long neutron tail (neutron halo) in the 11Be density distribution.

The angular distribution of Ti K X-rays and Sn L X-rays and their satellites due to 6 MeV/nucleon N-ion impact have been measured using an Si(Li) detector and an X-ray crystal spectrometer. The X-rays are observed to be isotropic.

A gyroscope is one of the most important mechanical components, used in wide variety of mechanical systems. Although many kinds of gyroscopes are commercially available, for consumer applications, lately becoming a big market for gyroscopes, a vibration gyroscope is the present standard. Vibration gyroscopes are small in size and low cost, however, they are not robust enough for external impact/vibration because they have vibrating elements inside.

Collisions between 1.05 MeV/amu Arq+ (q = 14, 10, 8 and 4) ions and CH4 molecules have been investigated using final charge-selected projectile-recoil ion time-of-flight technique. It is found that, in the overall ionization of target CH4 molecules, pure ionization processes without any change of the projectile charge is by far dominant over any other processes involving electron capture or loss of projectiles. Electron loss or capture processes of projectiles, though weak relative to pure ionization, are found to result in enhancement of the production of multiply charged atomic carbon ions. Another feature, probably not observed earlier, is the fact that in some electron loss and capture processes multiply charged carbon ions become more dominant than any other molecular ions, suggesting that such violent collisions result in nearly complete dissociation of the molecular ions.

A particle identification technique has been developed combining the use of a position-sensitive silicon detector with a simple magnetic system. Measurements of time of flight, energy loss, total energy, and magnetic rigidity provided the determination of the atomic number, the charge state, and the mass of produced fragments. The resultant resolutions were ΔA = 0.34 (FWHM) for mass number A = 40 and ΔZ = 0.24 (FWHM) for atomic number Z = 20.

The charge distributions and production cross sections of recoil ions accompanied by projectile electron loss and capture have been compared in 1.05-MeV/amu Ne{sup {ital q}+} ({ital q}=2, 4, 6, 8, and 10) +Ne collisions. While singly charged recoil ions are dominant in pure ionization processes, the production of highly charged recoil ions is strongly enhanced in collisions involving simultaneous charge change (by both electron loss and capture) of projectiles, and the charge distributions of recoil ions are found to be similar for both projectile loss and capture processes. These results have been analyzed with an independent-electron model and indicate that the dominant contribution to the production of higher-charge recoil ions comes from {ital L}-shell ionization, with some contribution from {ital K}-shell ionization of targets, accompanied by violent multiple ionization of projectiles.

An exclusive measurement of the Coulomb breakup of {sup 8}B into {sup 7}Be+p at 254A MeV was used to infer the low-energy {sup 7}Be(p,{gamma}){sup 8}B cross section. The radioactive {sup 8}B beam was produced by projectile fragmentation of 350A MeV {sup 12}C and separated with the FRagment Separator (FRS) at Gesellschaft fuer Schwerionenforschung in Darmstadt, Germany. The Coulomb-breakup products were momentum-analyzed in the KaoS magnetic spectrometer; particular emphasis was placed on the angular correlations of the breakup particles. These correlations demonstrate clearly that E1 multipolarity dominates within the angular cuts selected for the analysis. The deduced astrophysical S{sub 17} factors exhibit good agreement with the most recent direct {sup 7}Be(p,{gamma}){sup 8}B measurements. By using the energy dependence of S{sub 17} according to the recently refined cluster model for {sup 8}B of P. Descouvemont [Phys. Rev. C 70, 065802 (2004)], we extract a zero-energy S factor of S{sub 17}(0)=20.6{+-}0.8(stat){+-}1.2(syst) eV b. These errors do not include the uncertainty of the theoretical model to extrapolate to zero relative energy, estimated by Descouvemont to be about 5%.

Excited states of ${}^{34}\mathrm{Si}$ were studied in the ${}^{2}\mathrm{H}{(}^{34}\mathrm{Si}{,}^{34}\mathrm{Si}\ensuremath{\gamma})$ reaction using a radioactive ${}^{34}\mathrm{Si}$ beam at $38.4A\mathrm{MeV}$ and a liquid deuterium target. Deexcitation $\ensuremath{\gamma}$ rays were measured using a NaI(Tl)-scintillator array in coincidence with scattered ${}^{34}\mathrm{Si}$ particles. From $\ensuremath{\gamma}\ensuremath{-}\ensuremath{\gamma}$ coincidence analyses, the $\ensuremath{\gamma}$ lines at 1.193, 1.715, and 2.696 MeV, which were reported previously but unplaced in the level diagram, were found to be associated with the 3.326-MeV $\ensuremath{\gamma}$ line corresponding to the transition from the first ${2}^{+}$ state to the ground state. This excludes the 1.193-MeV line as a candidate for the transition from the ${2}^{+}$ state to the second ${0}^{+}$ state, as suggested by Nummela et al. [Phys. Rev. C 63, 044316 (2001)].

An exclusive measurement of the Coulomb breakup of 8 B into 7 Be + p at 254A MeV allowed the study of the angular correlations of the breakup particles. These correlations demonstrate clearly that El multipolarity dominates and that E2 multipolarity can be neglected. By using a simple single-particle model for 8 B and treating the breakup in first-order perturbation theory, we extract a zero-energy S factor of S 1 7 (0) = 18.6 ′ 1.2 ′ 1.0 eV b, where the first error is experimental and the second one reflects the theoretical uncertainty in the extrapolation.

Backscatter and attenuation properties of bright-band are computed at 10 and 34.5 GHz by two bright-band models. The first model assumes spherical particles with the composition of each particle being a uniform mixture of ice, water, and air. The second model assumes concentric spherical particles. Each particle has a snow core covered with water. The computed results are compared with the experimental results obtained by a dual-frequency air-borne radar in the case of tropical storm which was accompanied by bright-band. Three negative exponential type drop-size distributions, i.e. Marshall and Palmer distribution, Joss drizzle distribution, and Joss thunderstorm distribution, are used in the computations. The best agreement between computations and experimental results is obtained by the first model assuming Joss thunderstorm drop-size distribution. >

We report a new and simple optical fiber backreflectance method for accurate measurement of either focal lengths of optical elements or short distances by the spatial location of three specific points: the focal point and two object points.

Various secondary ions have been produced under 1.5-MeV/amu Ar 13+ -ion impact on a condensed CO target. Multiply charged C i+ and O i+ ions including H- and He-like ions have been observed to be unexpectedly large compared with condensed rare-gas targets and understood to be due to large initial kinetic energies, which are gained through Coulomb explosion of multiply charged molecular ions produced inside condensed targets during energetic collisions. The prominent positive cluster ions are [CO(CO) n ] + as expected, whereas the negative cluster ions are [C n ]

We have studied projectile K x-ray satellite yields in collisions between 50-MeV ${\mathrm{Ar}}^{\mathit{Q}+}$ ions (Q=4,6,11,12,13) and C foils with various thicknesses (2--100 \ensuremath{\mu}g/${\mathrm{cm}}^{2}$). For foil thicknesses below about 10 \ensuremath{\mu}g/${\mathrm{cm}}^{2}$, Q dependence of the yields has been observed, reflecting the nonimmediate L-shell equilibrium. For this region, it has been shown that the mean K-hole formation cross section also varies with the target thickness and Q. The variation has been attributed to the varying chance of K-to-L excitation with the increase or decrease of L holes in solid. The projectile charge fractions after passage through the target have also been measured for the foil-thickness region 2--20 \ensuremath{\mu}g/${\mathrm{cm}}^{2}$ including the thicknesses for which charge-state equilibrium is not attained. By combining these data, the K-hole formation cross section specifying the number of L holes at the initial stage of a collision has been estimated. The results have been compared with theoretical predictions for cross sections of K-to-continuum ionization and K-to-L excitation.

High-spin states of148Tb were studied by inbeam γ-ray spectroscopic techniques using141Pr(13C,6n)148Tb and27Al(130Te,9n)148Tb reactions. The level scheme of148Tb was established up to the excitation energy of 11.8MeV. The excitation energy of the high-spin isomer reported previously was revised to be 8.620MeV. The excited states below the isomer could be understood as resulted from the weak couplings of πh11/2 and νf7/2 to those of147Gd and147Tb, respectively.

High-spin states of145Sm were studied by using the20Ne(136Xe, α7n),139La (10B, 4n) and138Ba(13C,6n) reactions. The decay scheme of a high-spin isomer of145Sm was established. The excitation energy and the spin-parity of the isomer were determined to be 8.8 MeV and (49/2+), respectively. The level scheme was extended up to the (65/2) state at 14.6 MeV. The experimental results were discussed comparing with the deformed independent particle model (DIPM) calculation.

A new high-spin isomeric state with a half-life of ≥2μs was found in144Pm by observing the14N(136Xe,6n)144Pm reactions. The excitation energy and spin of the isomer were estimated to be ∼7.4 MeV and ∼27+, respectively. Filling gas in a recoil ion separator was used as the target material.

The stopping powers of Ni, Ag, Au, and Pb for approx.7-MeV/N (where N means nucleon) C ions and ..cap alpha.. particles have been measured. For the 7.00-MeV/N C ion, the stopping powers of Ni, Ag, Au, and Pb are found to be 1.353 +- 0.016, 1.080 +- 0.010, 0.832 +- 0.006, and 0.825 +- 0.006 MeV/mg cm/sup 2/, respectively. From these results, the Z/sub 1//sup 3/ deviation from the Bethe-Bloch formula is evaluated comparing with our experimental stopping power for ..cap alpha.. particles. In the course of analysis we employed appropriate effective-charge corrections. Pierce and Blann's effective-charge correction, e.g., gives a reasonable value (1.38) of the b which appears in the Ritchie-Brandt theory, if a chi value of 1.29 in their theory is assumed.

A mechanical beam chopper system combined with a Ge(Li) γ-ray detector has been developed which enables to measure half-lives of isometric states in the range from 1 to 900 ms. Values of (8.39±0.11) ms for the half-life of the 2.757 MeV isometric state in 132 Xe, (5.25±0.24) ms for the 95.2 keV state in 171 Yb and (6.19±0.08) ms for the 382 keV state in 90 Nb were obtained.

Charge-state distributions of Ar ions after single close collisions (impact parameter ∼1 × 10 −9 cm) with target gases of Ne, Ar, and Kr are measured. The impact parameters are selected so that the L-shell electrons of Ar ions play an important role in determining the resultant charge state. The experimental setup for the measurements of charge-state distributions of heavy ions consists of a magnet and a position-sensitive parallel-plate avalanche counter. Charge-state distributions of several kinds of ions (∼1 MeV/u) after passing through a carbon foil are also measured to test the experimental setup.

Some features have been described of the experimentally observed results on production of multiply charged atomic ions from molecular targets under highly charged, energetic heavy ion impact. In 1.05 MeV/amu Ar12+ ion collisions, I17+ ions have been observed, suggesting that multiply charged molecular ions as high as I233+, I234+ or I235+ ions are produced.