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Direct mass measurements of neutron-rich Kr-86 projectile fragments and the persistence of neutron magic number N=32 in Sc isotopes
No full text<span style="color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(248, 248, 248);">In this paper, we present direct mass measurements of neutron-rich Kr-86 projectile fragments conducted at the HIRFL-CSR facility in Lanzhou by employing the Isochronous Mass Spectrometry (IMS) method. The new mass excesses of 52-54SC nuclides are determined to be -40492(82), -38928(114), -34654(540) keV, which show a significant increase of binding energy compared to the reported ones in the Atomic Mass Evaluation 2012 (AME12). In particular, Sc-53 and Sc-64 are more bound by 0.8 MeV and 1.0 MeV, respectively. The behavior of the two neutron separation energy with neutron numbers indicates a strong sub-shell closure at neutron number N=32 in Sc isotopes.</span
Study of X-ray spectrum emitted due to the impact of ~(129)Xe~(q+) on different ion's charge on Au
No full text<span style="color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(248, 248, 248);">We report the experiment data of X-ray spectra produced by the impact of Xeq+ (q = 1 0, 15, 20, 26) with 2.4 MeV kinetic energy on Au surface in the National Laboratory of Heavy Ion Research Facility in Lanzhou. Results show that there is different broadening of Au M X-ray owing to multiply ionized effect in the collision with heavy ions, the degree of ionization mainly depends on the distribution of the electronic states in the ions' outer shell. The yield of X-ray is calculated and compared with BEA (binary encounter approximation) model, and the effect of ion charge state on the X-ray yield is also discussed.</span
Hillock formation on CaF2, Al2O3, c-SiO2 and MgO single crystal surfaces by ion impact - From potential energy deposition to electronic energy loss
No full text<span style="color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(248, 248, 248);">For impact of very slow highly charged ions on single crystal surfaces the appearance of hillocks can be linked to a threshold in potential energy while for swift heavy ions a minimum electronic energy loss per unit length is necessary. Recent investigations on CaF2 in the medium energy range bridge the gap between these two extreme cases. These investigations are now extended to other target materials.</span
Capture mode research in HIAF-CRing
No full text<span style="color: rgb(0, 0, 0); font-family: Arial, verdana, helvetica, sans-serif; line-height: 14px;">Three different modes for capturing heavy ions in CRing were investigated based on the study of longitudinal motion in HIAF. The typical beam of</span><sup style="color: rgb(0, 0, 0); font-family: Arial, verdana, helvetica, sans-serif; line-height: 14px;">238</sup><span style="color: rgb(0, 0, 0); font-family: Arial, verdana, helvetica, sans-serif; line-height: 14px;">U</span><sup style="color: rgb(0, 0, 0); font-family: Arial, verdana, helvetica, sans-serif; line-height: 14px;">34+</sup><span style="color: rgb(0, 0, 0); font-family: Arial, verdana, helvetica, sans-serif; line-height: 14px;">was injected from BRing with energy of 800 MeV/u, and its longitudinal momentum spread was ±5×10</span><sup style="color: rgb(0, 0, 0); font-family: Arial, verdana, helvetica, sans-serif; line-height: 14px;">-4</sup><span style="color: rgb(0, 0, 0); font-family: Arial, verdana, helvetica, sans-serif; line-height: 14px;">. The distribution of particles with different RF curves in longitudinal phase space was simulated using the code ESME, and the adiabatic capture mode was chosen as the basic working mode for CRing according to the simulation result. ©, 2015, Atomic Energy Press. All right reserved.(4 refs)</span
Transmission efficiency improvement of the injector line of SFC by particle beam decorrelation
No full text<span style="color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(248, 248, 248);">The operation of the HIRFL accelerator has shown that the beam transmission efficiency of the sector focusing cyclotron (SFC) injector line is rather poor. Beam simulations have been performed to investigate the possible causes for this low transmission. It is predicted that the property of transversal coupling of the ion beam from electron cyclotron resonance (ECR) ion source can be an important factor to degrade the beam quality by increasing the beam emittance, resulting in a serious particle loss. An improved operation scheme for the SECRAL associated line has been proposed, and the corresponding experiment was carried out. This paper presents the test results.</span
Structural damage in InGaN induced by MeV heavy ion irradiation
No full textIn0.18Ga0.82N films were irradiated with 4 MeV Kr-84 and 8.9 MeV Bi-209 ions to various fluences at room temperature. The irradiated films were analyzed by means of Rutherford backscattering/channeling (RBS/C) and high resolution X-ray diffraction (HRXRD). The RBS/C measurements show that under the irradiation conditions, the relative lattice disorder in the films, obtained from the normalized backscattering yield, exhibits a rapid increase in the range from similar to 2% to 68%. There is also an increasing lattice expansion of the films with increasing ion fluence, as determined by the HRXRD measurements. At a comparable level of lattice disorder, the Kr irradiation leads to a more pronounced lattice expansion than the Bi irradiation. This may be attributed to a larger portion of the single interstitials in the films produced by the lighter Kr ion irradiation. (C) 2015 Elsevier B.V. All rights reserved
