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This paper reports that the K x-ray spectra of the thin target (47)Ag, (48)Cd, (49)In and (50)Sn were measured by an HPGe semi-conductor detector in collisions with 84.5 MeV (6)C(4+) ions. Our experiment revealed the K alpha x-ray energy shifts were not obvious and the K beta(1) x-ray energy shifts were about 90 similar to 110 eV. The simple model of Burch et al has been previously used to calculate the K x-ray energy shifts due to an additional vacancy in 2p orbit. The present work extends the model of Burch to calculate the x-ray energy shifts of multiple ionized atoms induced by heavy ions with kinetic energy of MeV/u. In addition to our experimental results, many other experimental results are compared with the calculated values by using the model.

The values of direct double-to-single ionization ratio R of helium atoms induced by Cq+, Oq++ (q = 1–4) ions at incident energies from 0.2 to 8.5MeV are measured. Based on the existing model (Shao J X, Chen X M and Ding B W 2007 Phys. Rev. A 75 012701) the effective charge of the projectile is introduced to theoretically estimate the value of R for the partially stripped ions impacting on helium atoms. The results calculated from our 'effective charge' model are in good agreement with the experimental data, and the dependence of the effective charge on the ionization energy of the projectile is also discussed qualitatively.

This paper reports that the ratios of double to single electron loss cross-section (R) of O2+ in collision with Ar and He at the velocity of 1–4ν0 (ν0 is the Bohr velocity) have been obtained by the coincidence technique. The trend of R – V in the experiment indicates that the effective charge varies with injected velocity. The effective charge can be obtained by the n-body classical trajectory Monte Carlo method, which is interpreted by the molecular Coulomb over barrier model.

Using the slow highly charged ions Xe-129(q+) (q = 25, 26, 27; initial kinetic T-0

The ratios of transfer ionization (TI) to single-electron capture (SC) cross sections have been measured for the collisions of partially stripped Cq+ ions (q = 1-4) with He. The collision velocity ranges from 0.7 to 4.4v(0) (v(0) is the Bohr velocity). The projectile-ion and recoil-ion coincidence technique is used to separate the processes of TI and SC. The ratios reach the maximum when the velocity is about 3.7 v(0). This can be explained qualitatively based on the two-step mechanism. The experimental results are also compared with the results calculated using the classical trajectory Monte Carlo (CTMC) method. The CTMC results are in agreement with the experimental data basically. The discrepancies in higher velocity region are interpreted by the effective charge effect.

The relative partial cross sections for 13C6+–Ar collisions at 4.15–11.08 keV/u incident energy are measured. The cross-section ratios σ2E/σSC, σ3E/σSC, σ4E/σSC and σ5E/σSC are approximately the constants of 0.51±0.05, 0.20±0.03, 0.06±0.03 and 0.02±0.01 in this region. The significance of the multi-electron process in highly charged ions (HCIs) with argon collisions is demonstrated (σME/σSC as high as 0.79±0.06). In multi-electron processes, it is shown that transfer ionization is dominant while pure electron capture is weak and negligible. For all reaction channels, the cross-sections are independent of the incident energy in the present energy region, which is in agreement with the static characteristic of classic models, i.e. the molecular Coulomb over-the-barrier model (MCBM), the extended classical over-the-barrier model (ECBM) and the semiempirical scaling laws (SL). The result is compared with these classical models and with our previous work of 13C6+-Ne collisions [Chin. Phys. Lett. 23 (2006) 95].

The cross-section ratios of double-, triple-, quadruple-, and the total multi-electron processes to the single electron capture process (σDE/σSC, σTE/σSC, σQE/σSC and σME/σSC) as well as the relative ratios among reaction channels in double-electron active, triple-electron active and quadruple-electron active are measured in 13C6+–Ne collision in the energy region of 4.15–11.08 keV/u by employing position-sensitive and time-of-flight coincident techniques. It is determined that the cross-section ratios σDE/σSC, σTE/σSC, σQE/σSC and σME/σSC are approximately the constants of 0.20±0.03, 0.16±0.04, 0.06±0.02 and 0.42±0.05. These values are obviously smaller than the predictions of the molecular Coulomb over-the-barrier model (MCBM) [J. Phys. B 23 (1990) 4293], the extended classical over-the-barrier model (ECBM) [J. Phys. B 19 (1986) 2925] and the semiempirical scaling laws (SL) [Phys. Rev. A 54 (1996) 4127]. However, the relative ratios among partial processes of DE, TE and QE are found to depend on collision energy, which suggests that the collision dynamics depends on the collision velocity. The limitation of velocity-independent character of ECBM, MCBM and SL is undoubtedly shown.

In recent years, by using the etching techniques with great precision, the ion tracks in materials were converted into insulator and metal nanocapillaries. The physical and chemical properties of the inner surface on micro and nano-scales of these capillaries can be investigated by the interaction of ions with the surfaces. Stolterfoht et al. (2002 Phys. Rev. Lett. 88 133201) have found the evidence for capillary guiding in studying the transmission of 3 keV Ne7+ ions (energy/charge E/q approximate to 10(0) kV) through the polymer nanocapillaries. The self-organized charge-up process was thought to inhibit close contact between the ions and the inner capillary walls. Skog et al. (2008 Phys. Rev. Lett. 101 223202) investigated the guiding effect of 7 keV Ne7+ ions (E/q approximate to 10(0) kV) transmitted through SiO2 nanocapillaries, and found the evidence of sequentially formed charge patches along the capillary. For these keV highly charged ions with E/q approximate to 10(0) kV, the charge patches were formed in a very short time, and then the repulsive electric field rapidly becomes strong enough to deflect the ions, then the ions move along the capillary axis without charge exchange. Zhou et al. (2016 Acta Phys. Sin. 65 103401) have investigated the transmission of 100 keV protons (E/q approximate to 10(2) kV) through the nanocapillaries in polycarbonate (PC) membrane. It was found that the transmitted ions are located around the direction of the incident beam, rather than along the capillary axis. This indicated that the transmission mechanism of hundreds of keV protons through nanocapillaries is significantly different from that for keV highly charged ions. For 100 keV protons, several charge patches suppress the protons to penetrate into the surface, and the protons are transmitted via twice specular scattering near the surface and finally emitted along the incident direction. However, the study of the transmission of E/q approximate to 10(1) kV ions through nanocapillaries is still lacking. In this work, we measure the time evolution of the relative transmission rate, charge state and angular distribution as well as the full width at half maximum of 20 keV protons (E/q approximate to 10(1) kV) transmitted through the nanocapillaries in PC membrane at a tilt angle of +1 degrees. We observe a very long time pre-guiding period before the stable guiding process is established. During the pre-guiding period the direction of the transmitted H+ ions changes to the direction of capillary axis gradually. The transmitted H-0 particles are composed of two peaks: the higher and sharper one is nearly in the beam direction, the wider and lower one is around the guiding direction. With the continuous charging-up process, the intensities of the narrow and sharp peak of transmitted H-0 near the beam direction will decrease and disappear at the end. The data indicate that the scattering and guiding forces are both important for E/q approximate to 10(1) kV ions during the period of pre-guiding process, and the guiding force is dominant till a long time pre-guiding period is ended. This finding will fill in the gap between E/q approximate to 10(0) kV and 10(2) kV of previous studies of ions transmitted through nanocapillaries. It is also helpful for finding the applications of nano-and micro-sized ion beams produced by tapered glass capillary with E/q approximate to 10(1) kV.

In this paper we report the measurements of the K x-ray relative transition probabilities as follows: K-beta/K-alpha for the atomic numbers Z = 39, 51, 62, 63, 64, 66, 67 and 68; and K-alpha2/k(alpha1), k(beta1)(1)/k(alpha1), k(beta2)(1)/k(beta1)1, and k(beta3)/k(beta2) for the atomic numbers Z = 62, 63, 64, 66, 67 and 68 as induced by protons at an energy of 3 MeV. The experimental results obtained are then compared with relativistic Hartree-Fock calculations.

A simple model for the direct ionization and transfer ionization probabilities in A2+ +He collisions in a wide projectile energy range is proposed based on the Bohr–Lindhard model and the classical statistical model. The calculated cross sections are in satisfactory agreement with the experimental data available.

The multi-electron processes are investigated for 17.9–120 keV/u C1+, 30–323 keV/u C2+, 120–438 keV/u C3+, 287–480 keV/u C4+ incident on a helium target. The cross-section ratios of double electron (DE) process to the total of the single electron (SE) and the double electron process (i.e. SE+DE), the direct double electron (DDI) to the direct single ionization (DSI) as well as the contributions of DDI to DE and of TI to DE are measured using coincidence techniques. The energy and charge state dependences of the measured cross-section ratios are studied and discussed.

The isotopic bare ion 13C6+ was employed to collide with helium at 4.15–11.08 keV/u. The relative partial cross sections were measured by position-sensitive and time-of-flight coincident techniques. It is shown that the direct-ionization (DI) process can be completely ignored in this region, the transfer ionization (TI) process is the most important double-electron channel, and the probability of the pure double-electron capture (DC) process is quite small. The cross-section ratio of the total double-electron (DE) process (i.e. DC+TI) to the single-electron capture (SC) process is experimentally determined to be approximately a constant of 0.09±0.03 in this region, and this value is obviously smaller than the predictions of the classical over-barrier models and the semi-empirical scaling laws. It is found that the cross-section ratio of pure DC to DE decreases obviously as the projectile velocity increases. Because the pure DC process only comes from the radiation de-excitation following the DC process and are competed by the TI process (comes from the auto-ionization following the DC process), this implies that the population of the two captured electrons depends distinctly on the collision velocity. Comparison with works on Ar16+–He by Wu et al. [Phys. Rev. A 48 (1993) 3617] reveals that the strong projectile-dependent character of the pure DC process exists.

When a lambda hyperon was embedded in a nucleus, it can form a hypernucleus. The lifetime and its mass dependence of stable hypernuclei provide information about the weak decay of lambda hyperon inside nuclear medium. This work will introduce the Jefferson Lab experiment (E02-017) which aims to study the lifetime of the heavy hypernuclei using a specially developed fission fragment detection technique, a multi-wire proportional chamber operated under low gas pressure (LPMWPC). Presented here are the method and performance of the reconstruction of fission position on the target foil, the separation of target materials at different regions and the comparison and verification with the Mote Carlo simulation., Comment: 10 pages

The X-ray emission spectra produced by 2.4-6.0 MeV Xe20+ ions impacting on vanadium surface were measured. The V K-shell X-ray production cross sections were extracted from the experimental yield data and compared with the theoretical predictions of the binary encounter approximation (BEA), the plane wave born approximation (PWBA), and the energy-loss coulomb-repulsion perturbed-stationary-state relativist (ECPSSR). In order to predict reasonably the inner-shell ionization induced by highly charged heavy ions during the asymmetric collisions at near the Bohr velocity, the corrections of BEA model are discussed. It is found that the X-ray production cross section induced by highly charged heavy ions moving at near the Bohr velocity is on the magnitude of 1 barn, which is almost four orders of magnitude larger than that induced by proton. The ECPSSR, which is regarded as the best model to simulate the inner-shell ionization by light ions, may underestimate the experimental data at least three orders of magnitude. The PWBA model presents a prediction to the results on an order of magnitude better than the ECPSSR simulation, but gives a worse tendency than the BEA model. The BEA calculations, corrected both by Coulomb repulsion and effective nuclear charge, present the best agreement with the experimental results. It is proposed, that in the energy region near the Bohr velocity, during the asymmetric collisions of Xe20+ ions with V atoms, the K-shell electron of V is ionized by direct ionization, and that it can be described by the binary encounter process between the xenon ions and the bound electrons. The X-ray production cross section can be simulated by BEA model, but the corrections of Coulomb repulsion and effective nuclear charge must be considered.

We are currently investigating the spatial resolution of highly pixelated Cadmium Zinc Telluride (CZT) detector for imaging application. A 20 mm×20 mm×5 mm CZT substrate was fabricated with 600 μm pitch pixels (500 μm anode pixels with 100 μm gap) and coplanar cathode. Charge sharing between two pixels was studied using collimated a 122 keV gamma ray source. Experiments show a resolution of 125 μm FWHM for double-pixel charge sharing events when the 600 μm pixelated and 5 mm thick CZT detector biased at −1000 V. In addition, we analyzed the energy response of the 600 μm pitch pixelated CZT detector.

In this paper, we present a simple theoretical approach to calculate the multiple ionization of big atoms and molecules induced by very high-q fast projectiles in a strong coupling regime (q/v > 1). The results obtained from this approach are in excellent agreement with the available experimental data. A probable scenario of molecular multiple ionization by fast and very high-q projectiles is discussed. The very small computational time required here and the good agreement with the existing experimental data make it a good candidate for studying the multiple ionization of complex molecules under high linear energy transfers.

The K X-ray relative transition probabilities Kb/Ka of some elements for atomic numbers 23≤Z≤33 induced by 3 MeV protons were measured. The experimental results are compared with the relativistic Hartree-Fock (RHF) calculations. Good agreements have been obtained considering the experimental error.

We have measured the cross-section ratios of helium induced by Cq+ and Oq+ (q = 1?4) in an energy range from 20 keV/amu to 500 keV/amu, and obtained the two-dimensional spectra by employing the coincidence method combined with the MPA-3 data acquisition system. Hence, we obtain the ratios of total single-ionization cross-sections (SI, SC, SLSI, and DLSI), total double-ionization cross-sections (DI, DC, TI, SLDI, and DLDI) and cross-sections of every process (SI, SC, SLSI, DLSI, DI, DC, TI, SLDI, and DLDI), which induce the single-ionization and double-ionization, to the total cross sections respectively. The competitive relations between the reaction-channels and the experimental data law of each reaction-channel are revealed explicitly, and the qualitative explanations involved in those results are also presented accordingly.

In this paper a projectile ion-recoil ion coincidence technique is used to investigate the transfer ionization processes in collisions of 0.22–6.30 MeV Cq+ ions and 0.25–6.35 MeV Oq+ ions (q = 1, 2, 3, 4) with the He atom separately. The cross section ratio f of transfer ionization to single electron transfer is measured, and the dependence of f on both charge state q and energy E of the projectiles is investigated. The electron-structure and the mechanisms leading to transfer ionization affect the dependence of f on q and E. Our measurements, along with other data published previously, suggest a similar dependence of f on charge state and energy of projectile for partially stripped ions over a large energy range. The maximum value of f is approximately 0.17q0.60; the energy corresponding to maximum f is about 160q0.60 keV/u.

The properties of the Z = 117 isotopic chain are studied within the framework of the axially deformed relativistic mean field theory (RMFT) in the blocked BCS approximation. The ground-state properties, such as binging energies, deformations as well as the possible.. decay energies and lifetimes are calculated with the parameter set of NL-Z2 and compared with results from the finite range droplet model. The analysis by RMFT shows that the isotopes in the range of mass number A = 291 similar to 300 exhibit higher stability, which suggests that they may be promising nuclei to be hopefully synthesized in the lab among the nuclei Z = 117.

Rare earth elements Tb, Er and Lu were bombarded by protons with energies of 0.2-1.2 MeV, L-subshell ionization cross sections were obtained. Experimental ionization cross sections were compared with the predictions of the ECPSSR theory.