The Fusion-by-Diffusion model as a tool to calculate cross sections for the production of superheavy nuclei

This article summarizes recent progress in our understanding of the reaction mechanisms leading to the formation of superheavy nuclei in cold and hot fusion reactions. Calculations are done within the Fusion-by-Diffusion (FBD) model using the new nuclear data tables by Jachimowicz et al. [At. Data Nucl. Data Tables 138, 101393 (2021)]. The synthesis reaction is treated in a standard way as a three-step process (i.e., capture, fusion, and survival). Each reaction step is analyzed separately. Model calculations are compared with selected experimental data on capture, fissionlike and fusion cross sections, fusion probabilities, and evaporation residue excitation functions. The role of the angular momentum in the fusion step is discussed in detail. A set of fusion excitation functions with corresponding fusion probabilities is provided for cold and hot synthesis reactions.Comment: submitted to EPJ A Topical Issue: Heavy and Super-Heavy Nuclei and Elements: Production and Propertie

Embryo Culture of Lycopersicon esculentum × L. peruvianum Hybrid Genotypes Possessing Heat-stable Resistance to Meloidogyne incognita

Genotypes of Lycopersicon peruvianum (L.) Mill. and L. peruvianum var. glandulosum (Rick), selected from accessions that possess resistance to Meloidogyne incognita [(Kofoid and White) Chitwood] at high soil temperature (30C), were used as male parents in crosses with L. esculentum (Mill.) susceptible cultivars UC82, Lukullus, Tropic, and male-sterile line ms-31, respectively. The incongruity barrier between the two plant species was overcome by embryo callus and embryo cloning techniques. Hybridity of the F, progeny obtained from each cross was confirmed by differences in leaf and flower morphology, plant growth habits, and by acid phosphatase isozyme phenotypes using polyacrylamide gel electrophoresis. In greenhouse inoculation experiments, F1 plants were highly resistant to M. incognita in soil at 25 and 30C. These results confirmed the successful transfer and expression of heat-stable resistance to M. incognita from L. peruvianum to hybrids with L. esculentum as a preliminary step to introgressing additional root-knot nematode resistance into tomato.EEA AMBAFil: Cap, Guillermo Bartolome. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Área Metropolitana de Buenos Aires. Agencia de Extensión Rural La Plata; ArgentinaFil: Roberts, P.A. University of California, Riverside. Department of Hematology; Estados UnidosFil: Thomason, I.J. University of California, Riverside. Department of Hematology; Estados UnidosFil: Murashige, T. University of California, Riverside. Department of Hematology; Estados Unido

“The missing lights of Nairobi”: Cyclists' Perceptions of safety by cycling after-dark in Nairobi, Kenya

Promotion of cycling is important to reach the goals for climate mitigation of the Paris Agreement and Goals ofthe Agenda 2030. Sustainable transport, both rural and urban, could contribute to at least seven of the 17 Sustainable Development Goals (ITDP 2015). There is relatively little research on cycling in Africa, and there is also much less research on cycling at night. Some studies show the importance of road lighting for minimising the reduction in the numbers of cyclists after-dark and suggest 'only a minimal amount of lighting can promote cycling after-dark, making it an attractive mode of transport year-round' (Uttley at el. 2020). So far, these studies have little relation to the situation in developing countries, which is why a first study in Nairobi, Kenya, is carried out here as an example. ... [From: Introduction

Natural and projectively equivariant quantizations by means of Cartan Connections

The existence of a natural and projectively equivariant quantization in the sense of Lecomte [20] was proved recently by M. Bordemann [4], using the framework of Thomas-Whitehead connections. We give a new proof of existence using the notion of Cartan projective connections and we obtain an explicit formula in terms of these connections. Our method yields the existence of a projectively equivariant quantization if and only if an \sl(m+1,\R)-equivariant quantization exists in the flat situation in the sense of [18], thus solving one of the problems left open by M. Bordemann.Comment: 13 page

Freeze-out configuration properties in the 197Au + 197Au reaction at 23 AMeV

Data from the experiment on the 197Au + 197Au reaction at 23 AMeV are analyzed with an aim to find signatures of exotic nuclear configurations such as toroid-shaped objects. The experimental data are compared with predictions of the ETNA code dedicated to look for such configurations and with the QMD model. A novel criterion of selecting events possibly resulting from the formation of exotic freeze-out configurations, "the efficiency factor", is tested. Comparison between experimental data and model predictions may indicate for the formation of flat/toroidal nuclear systems

The InKiIsSy experiment at LNS: A study of size vs. isospin effects with 124Xe + 64Zn,64Ni reactions at 35 A MeV

In previous experiments, performed by CHIMERA Collaboration, a strong difference in the cross sections of “dynamical” PLF binary decay between neutron-poor 112Sn(35A MeV)+58Ni and neutron-rich 124Sn(35A MeV)+64Ni colliding systems has been reported. The same effect was not seen in the “statistical” binary decay. The observed difference was related to the different N/Z content between the two systems. However, size effects could not be excluded. In order to disentangle Isospin effects from size ones, the systems 124Xe(35A MeV)+64Zn(64Ni) were studied in the InKiIsSy (Inverse Kinematic Isobaric Systems) experiment, carried out at Laboratori Nazionali del Sud on April 2013, using the multi-detector CHIMERA and 4 prototype-modules of FARCOS array. We will report preliminary results on the binary PLF splitting mechanism

Signals of dynamical and statistical process from IMF-IMF correlation function

In this paper we briefly discuss about a novel application of the IMFIMF correlation function to the physical case of binary massive projectile-like (PLF) splitting for dynamical and statistical breakup/fission in heavy ion collisions at Fermi energy. Theoretical simulations are also shown for comparisons with the data. These preliminary results have been obtained for the reverse kinematics reaction 124Sn+64Ni at 35 AMeV that was studied using the forward part of CHIMERA detector. In that reaction a strong competition between a dynamical and a statistical components and its evolution with the charge asymmetry of the binary break up was already shown. In this work we show that the IMF-IMF correlation function can be used to pin down the timescale of the fragments production in binary fission-like phenomena. We also made simulations with the CoMDII model in order to compare to the experimental IMF-IMF correlation function. In future we plan to extend these studies to different reaction mechanisms and nuclear systems and to compare with different theoretical transport simulations