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A formalism calculating the cross sections of intermediate-energy proton direct capture populating continuum states has been developed. The transition amplitude includes two terms corresponding to potential-scattering to potential-scattering transitions and potential-scattering to resonance-scattering transitions, respectively. The model is compared with available experimental data of the $^{11}\mathrm{B}$(p,${\ensuremath{\gamma}}_{19}$${)}^{12}$C reaction, and the results show that within the reasonable parameter limit the direct capture mechanism is able to account for a major feature of the measured data, and, in the present case, the contributions from the two terms are of the same order of magnitudes. The physical significance of the results is discussed.

Absolute total-cross-section measurements have been performed on the [ital e][sup [minus]-]C[sub 2]H[sub 2] and [ital e][sup [minus]]-CO systems in the energy range 400--2600 eV. An apparatus with linear transmission technique was used. The estimated total experimental errors are about 5%. The results have been compared with available experimental and theoretical results. No previous data for [ital e]-C[sub 2]H[sub 2] have been found in the literature for impact energies above 400 eV.

In order to clarify whether statistical or dynamical treatments for emission of intermediate mass fragments (IMFs) will be needed in the intermediate energy heavy ion collisions, the measured angular and energy distributions of IMF (3 ≤ Z ≤ 6) in 25 MeV/n 40Ar+natAg were analyzed by means of statistical calculation code GEMINI and quantum molecular dynamics code (QMD). While the angular distribution calculations with GEMINI code are not compatible with the experimental ones, the QMD calculations for inclusive angular distributions and energy spectra of IMF are in good agreement with the measured ones.

Abstract Lanthanides doped luminescent materials (LLMs) have recently gained considerable attention in the areas of bioimaging, sensing, display, and lasers, benefitting from the intriguing optical characters of lanthanides. In LLMs, defect creates intermediate energy levels within the bandgap, which tailors the excited-state dynamics of lanthanides in photophysics and manipulates the spectroscopic characteristics of the lanthanides with much enhanced precision, and thus defect engineering could be a powerful tool in designing LLMs. In this review, we first discuss the creation and characterization of defects in LLMs, which are especially facilitated by the rapid development in nanofabrication, the state-of-the-art instrumental techniques and computation methods. This advances have pushed the manipulation, understanding and utilization of defects in LLMs to a whole new-level and the tailoring of LLMs with desinged performance to meet the requirements of specific application has been dramatically improved in recent years. We then review the emerging applications of the defect-involved LLMs ranging from colour displays, energy utilization, radiation detection to biological applications. Finally, we envision future potential directions in the research of defect engineerin of LLMs and highlight the unsolved problems in this rapidly growing field.

The pairing energy (${E}_{p}$) of fragments, which is assumed to have a finite temperature in heavy-ion collisions, is obtained using an isobaric yield ratio method in the framework of a modified Fisher model. The fragments in the measured and simulated $140A$ MeV $^{40,48}\mathrm{Ca}+\phantom{\rule{0.16em}{0ex}}^{9}\mathrm{Be}/^{181}\mathrm{Ta}$ and $^{58,64}\mathrm{Ni}+\phantom{\rule{0.16em}{0ex}}^{9}\mathrm{Be}/^{181}\mathrm{Ta}$ reactions have been adopted to perform the analysis. The results show that the ratio of the pairing-energy coefficient to the temperature (${a}_{p}/T$) is not significantly influenced by the reaction system, but depends on the neutron excess $(I=N\ensuremath{-}Z)$ of the fragment. For most fragments, ${a}_{p}/T$ falls in the range of $\ensuremath{-}1.0l{a}_{p}/Tl1.0$. Assuming $T\ensuremath{\approx}2.0$ MeV for the intermediate-mass fragments, ${a}_{p}\ensuremath{\sim}2.0$ MeV is suggested, which is much smaller than the value in the semiclassical mass formula. For a neutron-rich fragment, ${E}_{p}$ may disappear. The results are confirmed by the calculated ${E}_{p}$ of some $A=34$ isobars using the self-consistent finite-temperature relativistic Hartree-Bogoliubov model with the effective interaction PC-PK1 and the Gogny-pairing interaction D1S. The calculated ${E}_{p}$ depends on $T$ in the form of $y=Cexp(\ensuremath{-}a{T}^{4})$ and ${E}_{p}$ goes to zero fast with temperatures at around $T=0.8$ MeV. The results are useful for improving the secondary decay simulation for primary fragments in the heavy-ion collisions.

We propose a modified statistical model describing the disassembly of hot nuclei created in intermediate energy heavy-ion reactions. The calculated mass-yield distribution of fragments arising in {sup 12}C({ital E}/{ital A}=35 MeV)+{sup 63}Cu reactions agrees with experimental data quite well.

Abstract The dose equivalent of neutrons from intermediate energy heavy ion reactions measured with a rem-meter would be underestimated because of the energy response of the instrument. The correlation factors for dose equivalent of neutrons from the reactions of 41.7 MeV/ u 12 C + Fe and 100 MeV/ u 12 C + C measured with both rem-meters, 10in diameter single-sphere rem-meter and standard A-B rem-meter, have been calculated. It could be applied in dose-equivalent measurement for intermediate energy heavy ion reactions.