Search results for "force"
showing 10 items of 3423 documents
Simulating core excitation in breakup reactions of halo nuclei using an effective three-body force
2022
We extend our previous calculation of the breakup of 11Be using Halo Effective Field Theory and the Dynamical Eikonal Approximation to include an effective 10Be-n-target force. The force is constructed to account for the virtual excitation of 10Be to its low-lying 2+ excited state. In the case of breakup on a 12C target this improves the description of the neutron-energy and angular spectra, especially in the vicinity of the 11Be 5/2+ state. By fine-tuning the range parameters of the three-body force, a reasonable description of data in the region of the 3/2+ 11Be state can also be obtained. This sensitivity to the three-body force's range results from the structure of the overlap integral …
Nonlocal energy density functionals for pairing and beyond-mean-field calculations
2017
We propose to use two-body regularized finite-range pseudopotential to generate nuclear energy density functional (EDF) in both particle-hole and particle-particle channels, which makes it free from self-interaction and self-pairing, and also free from singularities when used beyond mean field. We derive a sequence of pseudopotentials regularized up to next-to-leading order (NLO) and next-to-next-to-leading order (N2LO), which fairly well describe infinite-nuclear-matter properties and finite open-shell paired and/or deformed nuclei. Since pure two-body pseudopotentials cannot generate sufficiently large effective mass, the obtained solutions constitute a preliminary step towards future imp…
Solution of universal nonrelativistic nuclear DFT equations in the Cartesian deformed harmonic-oscillator basis. (IX) HFODD (v3.06h) : a new version …
2021
We describe the new version (v3.06h) of the code HFODD that solves the universal nonrelativistic nuclear DFT Hartree-Fock or Hartree-Fock-Bogolyubov problem by using the Cartesian deformed harmonic-oscillator basis. In the new version, we implemented the following new features: (i) zero-range three- and four-body central terms, (ii) zero-range three-body gradient terms, (iii) zero-range tensor terms, (iv) zero-range isospin-breaking terms, (v) finite-range higher-order regularized terms, (vi) finite-range separable terms, (vii) zero-range two-body pairing terms, (viii) multi-quasiparticle blocking, (ix) Pfaffian overlaps, (x) particle-number and parity symmetry restoration, (xi) axializatio…
Smooth crack-free targets for nuclear applications produced by molecular plating
2013
The production process of smooth and crack-free targets by means of constant current electrolysis in organic media, commonly known as molecular plating, was optimized. Using a Nd salt, i.e., [Nd(NO3)(3)center dot 6H(2)O], as model electrolyte several constant current density electrolysis experiments were carried out to investigate the effects of different parameters, namely the plating solvent (isopropanol and isobutanol mixed together, pyridine, and N,N-dimethylformamide), the electrolyte concentration (0.11, 0.22, 0.44 mM), the applied current density (0.17, 0.3, 0.7, and 1.3 mA/cm(2)), and the surface roughness of the deposition substrates (12 and 24 nm). Different environments (air and …
On the double-beta decays of 70Zn, 86Kr, 94Zr, 104Ru, 110Pd and 124Sn
2011
Abstract Double-beta decays of 70Zn, 86Kr, 94Zr, 104Ru, 110Pd and 124Sn to the final ground states and the decays of 110Pd and 124Sn to the excited states in 110Cd and 124Te are studied in the framework of the proton–neutron quasiparticle random-phase approximation (pnQRPA) combined with the multiple-commutator model (MCM) for description of decays to the excited final states. Reasonably large single-particle model spaces and G-matrix-based effective nuclear forces are used to compute the relevant nuclear matrix elements and decay half-lives. The present study is among the very few that have been dedicated to double-beta decays of these nuclei, although the associated double-beta Q values e…
Meson and isobar degrees of freedom in light nuclei
1983
The role of mesonic and isobar degrees of freedom in various electromagnetic processes is reviewed for light nuclei. Special emphasis is laid on the deuteron, which allows the cleanest answers within the non-relativistic framework. The origin of the photonuclear enhancement with respect to both exchange forces and exchange currents is discussed in detail.
Erratum to: Quark mass dependence of the nuclear forces
2003
A general overview of the organocatalytic intramolecular aza-Michael reaction
2014
The organocatalytic intramolecular aza-Michael reaction gives access to enantiomerically enriched nitrogen-containing heterocycles in a very simple manner. Enals, enones, conjugated esters and nitro olefins have been employed as Michael acceptors, while moderate nitrogen nucleophiles such as sulphonamides, carbamates and amides have been shown to be appropriate Michael donors in this type of reaction. Additionally, the process has been performed under both covalent and non-covalent catalysis, with diaryl prolinols, imidazolidinones, thioureas and chiral binol phosphoric acids being the most frequently used catalysts. The level of efficiency reached with this protocol is demonstrated by the …
Tandem gold self-relay catalysis for the synthesis of 2,3-dihydropyridin-4(1 H)-ones: combination of σ and π Lewis acid properties of gold salts.
2014
The dual ability of gold salts to act as π- and σ Lewis acids has been exploited in a tandem self-relay catalysis. Thus, triphenylphosphanegold(I) triflate mediated the intramolecular carbonyl addition of the amide functionality of homoprogargyl amides to a triple bond. The formation of a σ complex of the gold salt with the intermediate oxazine promoted a nucleophilic addition followed by a Petasis-Ferrier rearrangement. This tandem protocol, catalyzed by the same gold salt under the same reaction conditions, gave rise to the efficient synthesis of 2,3-dihydropyridin-4-(1 H)-ones, which contain a cyclic quaternary α-amino acid unit. The asymmetric version was performed by generating the sta…
1,4-Benzoquinones with Styryl Substituents
2002
2-Styryl-1,4-benzoquinone (1) and compounds 2 and 3 containing 1 as a substructure all proved to be highly reactive towards thermal or photochemical [4π + 2π] cyclodimerization reactions. Chemo-, regio- and stereoselective processes lead to dimers (compounds 1−10), which can undergo secondary reactions consisting of the addition of nucleophiles combined with a twofold keto-enol tautomerism (10 ⇄ 12). An alternative process is dehydrogenation/oxidation followed by an intramolecular [4π + 2π] cycloaddition (10 ⇄ 11). The same selective [4π + 2π] cyclodimerization can be observed in solution upon irradiation (e.g., 1a ⇄ 10a), in contrast to irradiation in the crystalline state which yields a […