Integral relations and the adiabatic expansion method for 1+2 reactions above the breakup threshold: Helium trimers with soft-core potentials

The integral relations formalism introduced in \cite{bar09,rom11}, and designed to describe 1+$N$ reactions, is extended here to collision energies above the threshold for the target breakup. These two relations are completely general, and in this work they are used together with the adiabatic expansion method for the description of 1+2 reactions. The neutron-deuteron breakup, for which benchmark calculations are available, is taken as a test of the method. The s-wave collision between the $^4$He atom and $^4$He$_2$ dimer above the breakup threshold and the possibility of using soft-core two-body potentials plus a short-range three-body force will be investigated. Comparisons to previous calculations for the three-body recombination and collision dissociation rates will be shown.Comment: To be published in Physical Review

General integral relations for the description of scattering states using the hyperspherical adiabatic basis

In this work we investigate 1+2 reactions within the framework of the hyperspherical adiabatic expansion method. To this aim two integral relations, derived from the Kohn variational principle, are used. A detailed derivation of these relations is shown. The expressions derived are general, not restricted to relative $s$ partial waves, and with applicability in multichannel reactions. The convergence of the ${\cal K}$-matrix in terms of the adiabatic potentials is investigated. Together with a simple model case used as a test for the method, we show results for the collision of a $^4$He atom on a \dimer dimer (only the elastic channel open), and for collisions involving a $^6$Li and two $^4$He atoms (two channels open).Comment: Accepted for publication in Physical Review

Variational description of continuum states in terms of integral relations

Two integral relations derived from the Kohn Variational Principle (KVP) are used for describing scattering states. In usual applications the KVP requires the explicit form of the asymptotic behavior of the scattering wave function. This is not the case when the integral relations are applied since, due to their short range nature, the only condition for the scattering wave function $\Psi$ is that it be the solution of $(H-E)\Psi=0$ in the internal region. Several examples are analyzed for the computation of phase-shifts from bound state type wave functions or, in the case of the scattering of charged particles, it is possible to obtain phase-shifts using free asymptotic conditions. As a final example we discuss the use of the integral relations in the case of the Hyperspherical Adiabatic method.Comment: 34 pages, 7 figures, accepted in Phys. Rev.

Quality of table olives

6 páginas, 4 tablas.-- Articulo de revisión.[ES] El trabajo comenta las diferentes normas, tanto nacionales como intemacionales, que regulan los aspectos de la calidad de las aceitunas de mesa. Se comentan especialmente la Norma Cualitativa Unificada Aplicable a Aceitunas de Mesa en el Comercio Intemacional y las correspondientes COI/CODEX (Consejo Oleícola Intemacional, COI, y COI/Codex Alimentarius, respectivamente), la Reglamentación Técnico Sanitaria para la elaboración, circulación, y venta de aceitunas de mesa (española), las Normas de calidad para la exportación de Aceitunas de Mesa (española), y las «United States Standards for Grades of Green and Canned Ripe Olives» (USA). Asimismo se analizan las implicaciones de las nuevas reglamentaciones sobre etiquetado nutricional (principalmente en el comercio con USA), la aplicación del Análisis de Riesgos y Control de Puntos Críticos (ARCPC), y la necesidad de adaptar el Sector al cumplimiento de las diversas normas de la serie ISO 9000 o su equivalente EN 29000.[EN] The paper comments the different regulations related to table olives at national or international scales. The Unified Qualitative standard Applying to Table Olives in International Trade and COI/Codex (International Olive Oil Council, IOC, and IOC/Codex Alimentarius), «Reglamentación Técnico Sanitaria para la elaboración, circulación y venta de aceitunas de mesa» (Spanish), «Normas de calidad para la exportación de aceitunas de mesa» (Spanish), and the United States Standards for Grades of Green and Canned Ripe Olives (USA) are especially considered. The effects of the new regulations on Nutritional Labelling (mainly in USA), applications of the Analysis and Control of Critical Points (ACCP), and the problems derived from the application of the ISO 9000, or EN 29000, to this Sector are also discussed.Peer reviewe

Three-body structure of low-lying 12Be states

We investigate to what extent a description of 12Be as a three-body system made of an inert 10Be-core and two neutrons is able to reproduce the experimental 12Be data. Three-body wave functions are obtained with the hyperspherical adiabatic expansion method. We study the discrete spectrum of 12Be, the structure of the different states, the predominant transition strengths, and the continuum energy spectrum after high energy fragmentation on a light target. Two 0+, one 2+, one 1- and one 0- bound states are found where the first four are known experimentally whereas the 0- is predicted as an isomeric state. An effective neutron charge, reproducing the measured B(E1) transition and the charge rms radius in 11Be, leads to a computed B(E1) transition strength for 12Be in agreement with the experimental value. For the E0 and E2 transitions the contributions from core excitations could be more significant. The experimental 10Be-neutron continuum energy spectrum is also well reproduced except in the energy region corresponding to the 3/2- resonance in 11Be where core excitations contribute.Comment: 16 pages, 9 figures. Accepted for publication in Physical Review

In silico logistic model for table olive related microorganisms as a function of sodium metabisulphite, cinnamaldehyde, pH, and Type of acidifying agent

A probabilistic/logistic model, based on binary data (growth/no growth), was used to assess the effects of sodium metabisulphite (SM) and cinnamaldehyde (CIN; 0-1000 mg/L) against the main microbial groups found in table olive environment [lactic acid bacteria (LAB), yeasts, and Enterobacteriaceae], according to pH (range 3.5-5.0), and type of acidifying agent (HCl or pyruvic acid). The inhibitory effect of SM depended on the pH while that of CIN was scarcely influenced by it (except for LAB). LAB were more sensitive to SM, while yeasts were to CIN. The use of pyruvic acid for correction of pH always produced a reduction (compared to HCl) of the inhibitory power of both preservatives. The in silico models for HCl showed that, at pH 4.0, and growth probability 0.01, the LAB population might be inhibited by the presence in the medium of 150 mg/L SM or 1000 mg/L CIN, while in the case of yeasts, 450 mg/L SM, or 150 mg/L CIN are required. No growth of Enterobacteriaceae was observed at this (or lower) pH level. The results obtained may contribute to the stabilization of non-thermally treated table olive packaging.This research has received funding from INTERACEITUNA (Organización Interprofesional de la Aceituna de Mesa, Spain) and the Junta de Andalucía. FNAL thanks to the Spanish Government and CSIC for his Ramón y Cajal postdoctoral research contract, while VR thanks the AgriFood Campus of International Excellence (ceiA3), Bank of Santander, Spanish Government and “Aloreña de Málaga” Olive Manufacturing Association for her pre-doctoral fellowship (training and formation program of Ph.D. in companies).Peer Reviewe

Domestic space heating dynamic costs under different technologies and energy tariffs: Case study in Spain

Dynamic energy tariffs facilitate engaging domestic consumers on demand management, contributing to grid’s stability, but requires of informed decision enabling tools. This paper presents a domestic heating costs calculation method for different heating technologies (gas boiler, heat-pumps) and a range of energy tariffs. Based on physical modeling, effect of outdoor temperature in the COP of heat-pumps is assessed. The methodology is applied to the 2018/19 heating season in Madrid (Spain), calculating the heating costs under four diverse energy tariffs (static gas tariff, static electricity tariff, real-time-price electricity tariff, dynamic time-of-use electricity tariff) for a typical home demand. The hourly results for two representative days are detailed, along with the aggregated results for the whole season. Along the season, the continuous changes in energy wholesale market prices and weather conditions make one heating technology and/or tariff more convenient each time. For the whole season, the dynamic time-of-use tariff considered would imply heating costs up to 40% lower than the static gas tariff. The results are strongly conditioned by climate conditions and national energy market evolutions. Day-ahead information on the actual heating costs might lead to domestic end-users to adapt their behavior and consumption patterns for more cost-effective use of the energy.Research leading to these results has been supported by HOLISDER project. This project has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No. 768614. This paper reflects only the authors’ views and the Commission is not responsible for any use that may be made of the information contained therein

Integral relations for three-body continuum states with the adiabatic expansion

Application of the Hyperspherical Adiabatic expansion to describe three-body scattering states suffers the problem of a very slow convergence. Contrary to what happens for bound states, a huge number of hyperradial equations has to be solved, and even if done, the extraction of the scattering amplitude is problematic. In this paper we show how to obtain accurate scattering phase shifts using the Hyperspherical Adiabatic expansion. To this aim two integral relations, derived from the Kohn Variational Principle, are used. The convergence of this procedure is as fast as for bound states.Comment: 4 pages, 1 figur

Isomeric 0- halo-states in 12Be and 11Li

We predict the existence of an isomeric 0$^-$-state in $^{12}$Be at an excitation energy of about 2.5 MeV, and a 0$^-$-resonance in $^{11}$Li with both energy and width of about 1 MeV corresponding to two-neutron emission. The structure of these halo-like states are like the 1$^-$-states which means essentially a core surrounded by two neutrons in single-particle $s$ and p-states. The life-time of the $^{12}$Be state is determined by $M1$ or $M2$-emission, $\tau(M1) \approx 10^{-11}$ s or $\tau(M2) \approx 10^{-8}$ s estimated for photon energies of 0.1 MeV and 0.6 MeV, respectively.Comment: to be published in Physics Letters

Three-body structure of low-lying 18Ne states

We investigate to what extent 18Ne can be descibed as a three-body system made of an inert 16O-core and two protons. We compare to experimental data and occasionally to shell model results. We obtain three-body wave functions with the hyperspherical adiabatic expansion method. We study the spectrum of 18Ne, the structure of the different states and the predominant transition strengths. Two 0+, two 2+, and one 4+ bound states are found where they are all known experimentally. Also one 3+ close to threshold is found and several negative parity states, 1-, 3-, 0-, 2-, most of them bound with respect to the 16O excited 3- state. The structures are extracted as partial wave components, as spatial sizes of matter and charge, and as probability distributions. Electromagnetic decay rates are calculated for these states. The dominating decay mode for the bound states is E2 and occasionally also M1.Comment: 17 pages, 5 figures (version to appear in EPJA