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We study the transport property of single C60 molecular transistors with special focus on the situation that other molecules are in vicinity. The devices are prepared using electromigration and thermal deposition techniques. Pure single C60 molecule transistors show typical coulomb blockade behavior at low temperature. When we increase the coverage of molecules slightly by extending the deposition time, the transport spectrum of devices displays a switching behavior in the general coulomb blockade pattern. We attribute this unconventional phenomenon to the influence from a nearby C60 molecule. By analyzing this transport behavior quantitatively based on the parallel-double-quantum-dot model, the interaction from the nearby molecule is proved to be of capacity and tunneling coupling. Thermal stimulation is also applied to the device to investigate the effect of local charging environment variation on intermolecular interaction.

The β-delayed neutron and γ energy spectra taken from the decay of neutron-rich nucleus 21N were measured by using the β–γ and β – n coincidence detection method. Thirteen new neutron groups ranging from 0.28MeV to 4.98MeV and with a total branching ratio of 88.7 ± 4.2% were observed and presented. One γ transition with an energy of 1222keV emitted from the excited state of 21O, and four γ transitions with energies of 1674, 2397, 2780, and 3175keV emitted from the excited states of 20O were identified in the β decay chain of 21N. The β decay half-life for 21N is determined to be 82.9 ± 1.9 ms. The uncertainty of half-life is much smaller than the previous result.

Based on both very obvious isospin effect of the neutron–proton number ratio of nucleon emissions (n/p)nucl on symmetry potential and (n/p)nucl's sensitive dependence on symmetry potential in the nuclear reactions induced by halo-neutron projectiles, compared to the same mass stable projectile, probing symmetry potential is investigated within the isospin-dependent quantum molecular dynamics with isospin and momentum-dependent interactions for different symmetry potentials U1sym and U2sym. It is found that the neutron-halo projectile induces very obvious increase of (n/p)nucl and strengthens the dependence of (n/p)nucl on the symmetry potential for all the beam energies and impact parameters, compared to the same mass stable projectile under the same incident channel condition. Therefore (n/p)nucl induced by the neutron-halo projectile is a more favourable probe than the normal neutron-rich and neutron-poor projectiles for extracting the symmetry potential.

We study the average property of the isospin effects of reaction mechanism induced by neutron-halo nuclei within the isospin-dependent quantum molecular dynamics model. We find that the extended neutron density distribution for the neutron-halo projectile brings an important isospin effect into the reaction mechanism, which induces the decrease of nuclear stopping R; however, it induces the obvious increases of the neutron-proton ratio of nucleon emissions (n/p)nucl for all of the beam energies in this work, compared to the same mass stable colliding system.

Distribution of the parallel momentum of $^{28}$Si fragments from the breakup of 30.7 MeV/nucleon $^{29}$P has been measured on C targets. The distribution has the FWHM with the value of 110.5 $\pm$ 23.5 MeV/c which is consistent quantitatively with Galuber model calculation assuming by a valence proton in $^{29}$P. The density distribution is also predicted by Skyrme-Hartree-Fock calculation. Results show that there might exist the proton-skin structure in $^{29}$P., Comment: 4 pages, 4 figures

Spectra of carbon-, boron-, beryllium-, lithium-, helium-, and hydrogen-like sulfur ions were obtained and studied for the wavelengths below 200 A and the energy of 80 MeV by using beam-foil method. Thirty-five lines have been identified, in which 15 lines are newly accurately measured. The spectra were analysed based on the theoretical results and other experimental data.

We measured the visible light spectral lines of sputtering atoms from solid surfaces of Al, Ti, Ni, Ta and Au which are impacted by 150 keV 126Xeq + (6≤q≤30). It is found that intensities of the light spectral lines are greatly and suddenly enhanced when the charge state of the ion is raised up to a critical value. If assuming that potential energy released from the incident ion due to capturing one electron is enough to excite a surface plasmon, we can estimate the critical charge states and obtain the results very well consistent with the measurements for the above-mentioned target materials. This means that a surface plasmon induced by one electron capture can enhance the excitation of atomic visible light spectral lines in the impact of a highly charged ion on a solid surface.

Measurements of the total reaction cross sections (sigma (R)) for some proton-rich nuclei (N = 11 - 15 isotones) on a carbon target at intermediate energies have been performed on the Radioactive Ion Beam Line of the Heavy Ion Research Facility in Lanzhou. A larger enhancement of sigma (R) for P-27 has been observed than for its neighbours. Evidence for a proton halo in P-27 has been revealed in the Glauber analysis of the total reaction cross sections in terms of the difference factor d.

The relative sputtering yield induced by highly charged Arq+ impacting on Nb surface is investigated. The yield increases drastically as the incidence angle increases. A formula Y=A* tan(B) (theta) + C, developed from classical sputtering theory, fits well with the yield. By analysing a series of coefficients A and C extracted by curve fitting, the results demonstrate the presence of a synergy of the linear cascade collision and potential energy deposition.

The differential cross sections of 17F and 17O elastic scattering products on 208Pb have been measured at the Radioactive Ion Beam Line at Lanzhou (RIBLL). Two angular dispersion plots of ln (dσ/dθ) versus θ2 are obtained from the angular distribution of the elastic scattering differential cross sections. The angular dispersion plot exhibits a clear turning point for 17F in the range of small scattering angles 6°–20° due to its exotic structure, but for 17O, the turning point is not observed in the same angular range. The experimental results have been compared with previous data of other groups. Systematical analysis on the available data supports the above conclusion that there is an exotic behaviour of the angular dispersion plot of weakly bound nuclei with halo or skin structure as compared with that of the ordinary nuclei near stable line. Therefore the turning point of the angular dispersion plot appears at small angle for weakly bound nuclei with halo or skin structure, and can be used as a new probe to investigate the halo and skin phenomena of weakly bound nuclei.

The total reaction cross sections (TRCSs) of 29S+28Si have been measured at intermediate energies. An obvious enhancement in TRCS of 29S is observed as compared with its neighbouring nuclei. The TRCSs of 29S+28Si are calculated with the modified Glauber theory in the optical limit and few-body approaches. The different factor d as a possible measure of halo appearance is deduced from the experimental and theoretical data. It is well accepted that 27P is a proton halo nucleus. Although not as anomalous as 27P, the different factor d of 29S is obviously larger than that of its neighbouring isotones of N = 13. This result indicates that a moderate proton halo may exist in 29S nucleus. We calculate the total reaction cross sections for 29S with the modified Glauber theory as a function of incident energy and compare the results with those for 27Si which is a core nucleus of 29S. The measured TRCSs of 27Si+28Si can be described to be satisfactory by the modified Glauber theory of the optical limit approach. Although a diffused nuclear density distribution is used, the theories still inadequately predict the experimental TRCSs of 29S+28Si, which further indicates the possibility of proton halo in 29S.

Total reaction cross sections sigma (R) for some proton-rich isotones (N = 10) near Al-23 on a carbon target have been measured at intermediate energies in the experiment performed at the Radioactive Ion Beam Line of the Heavy Ion Research Facility in Lanzhou. The Z-dependence Of sigma (R) shows a remarkable enhancement for Al-23 relative to its neighbours. The difference factor d has been deduced from the measured sigma (R) by using the Glauber or Boltzmann-Uehling-Uhlenbeck models. From the above analysis, a possible one-proton halo structure is suggested for Al-23.

fragments produced in the reactions of 69 MeV/nucleon Ar-36 and 55 MeV/nucleon Ar-40 on a Be target have been measured experimentally. The isotopic distributions from fragmentation reaction for both projectiles are reproduced by using a modified statistical abrasion-ablation model. the isotopic distributions produced in Ar-36 and Ar-40 fragmentation. disappearance of the isospin effect in the fragmentation reaction. A strong isospin effect is exhibited in Experimental evidence is seen for the disappearance of the isospin effect in the fragmentation reaction.

Measurements of the total reaction cross section for C12-16, N14-17 and O16-18 on carbon target at intermediate energies were performed on RIBLL of HIRFL. A larger enhancement of sigma(n) for C-15 was observed than that for its neighbors. The analysis of these data indicates possible existence of an anomalous nuclear structure in C-15. A new quantity was suggested as the criterion to distinguish anomalous structure nuclei from normal nuclei.

Fragments produced in the reaction of 60MeV/n O-18 On Be have been measured experimentally. The isotopic distribution of fragmentation reaction is well reproduced by a modified statistical abrasion-ablation model. It is predicted that the isotopic distribution shifts toward the neutron rich side for neutron rich projectile, but this isospin effect decreases with the increase of the atomic number difference Z - Z(A) and disappears at last, where Z and Z(A) are atomic numbers of the isotopic distribution and the projectile respectively.

The quasi-elastic scattering of a secondary 6He beam (25 MeV/n) on a 9Be target has been measured for the first time with the application of a sophisticated tracking detector system. The angular distribution is reported. A phenomenological optical potential is obtained by fitting the experimental data, which encourages more accurate experimental measurements.

Highly charged 129Xeq+ (q = 10−30) and 40Neq+ (q = 4−8) ion-induced secondary electron emissions on the surface of highly oriented pyrolytic graphite (HOPG) are reported. The total secondary electron yield is measured as a function of the potential energy of incident ions. The experimental data are used to separate contributions of kinetic and potential electron yields. Our results show that about 4.5% and 13.2% of ion's potential energies are consumed in potential electron emission due to different Xeq+ -HOPG and Neq+ -HOPG combinations. A simple formula is introduced to estimate the fraction of ion's potential energy for potential electron emission.

We measured the total reaction cross sections of 12N in Si at 36.2 MeV/u using B.adioactive Ion Beam Line in Lanzhou (RIBLL) with a new method. The reaction target was installed at the intermediate focusing point T1 at RIBLL. This scheme allows us to identify particles before and after the reaction target unambiguously. The total reaction cross section (1760 ± 78 mb) of 12N in Si is obtained. Assuming that 12N consists of a core 11C plus one halo proton, the excitation function of N on the Si and C targets is calculated with the Glauber model and the Fermi–Fermi density distributions. It can fit the experimental data very well. A large diffusion of the protons density distribution supports the halo structure for 12N.

Angular distribution and current dependence of the transmitted ion fraction are investigated for 40keV Xe7+ bombarding on polycarbonate (PC) nanocapillaries. By measuring the angular distribution of the transmitted ion fraction, a strong guiding effect is found in PC nanocapillaries. Furthermore, with increase of the incident current, a turning point of the transmitted ion fraction is found, which is explained qualitatively by the discharge capacity of the nanocapillaries.