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The 235U(n,f) cross section was measured in a wide energy range (25 meV - 170 keV) at the n_TOF facility at CERN, relative to 6Li(n,t) and 10B(n,alpha) standard reactions, with high resolution and accuracy, with a setup based on a stack of six samples and six silicon detectors placed in the neutron beam. In this paper we report on the results in the region between thermal and 10 keV neutron energy. A resonance analysis has been performed up to 200 eV, with the code SAMMY. The resulting fission kernels are compared with the ones extracted on the basis of the resonance parameters of the most recent major evaluated data libraries. A comparison of the n_TOF data with the evaluated cross sections is also performed from thermal to 10 keV neutron energy for the energy-averaged cross section in energy groups of suitably chosen width. A good agreement is found in average between the new results and the latest evaluated data files ENDF-B/VIII and JEFF-3.3, as well as with respect to the IAEA reference files. However, some discrepancies are still present in some specific energy regions. The new dataset here presented, characterized by unprecedented resolution and accuracy, can help improving the evaluations in the Resolved Resonance Region and up to 10 keV, and reduce the uncertainties that affect this region.

Additional file 1: Table S1. Variables collected in the COVID-VIT-D trial. T. Table S2. Symptoms at discharge. Table S3. Biochemical parameters at discharge. Table S4. Demographic, comorbidities, and serum calcidiol categories at hospital admission. Table S5. Relevant biochemical parameters and serum calcidiol categories at hospital admission. Table S6. Relevant biochemical parameters and serum calcidiol categories at hospital admission in age-matched patients. Table S7. Pulmonary involvement at admission and outcomes according to serum calcidiol categories. Table S8. Types and number of drugs received during the hospitalization and serum calcidiol categories at hospital admission. Table S9. Demographic, comorbidities, and serum calcidiol categories at admission in age-matched patients. Table S10. Types and number of drugs received during the hospitalization and serum calcidiol categories at hospital admission in age-matched patients. Table S11. Relevant biochemical parameters and serum calcidiol categories at hospital admission in the control group (No cholecalciferol). Table S12. Types and number of drugs received during the hospitalization and serum calcidiol categories at hospital admission in the control group (No cholecalciferol). Table S13. Pulmonary involvement at admission and outcomes according to initial serum calcidiol categories in the control group (No cholecalciferol).

Additional file 2. Original trial protocol.

Additional file 3. COVID-VIT-D collaborators and affiliations.

El bombeo de morteros, tanto secos como h��medos cobra mayor importancia cada d��a, desplazando en muchos casos de forma total a los m��todos tradicionales para su transportaci��n. En el presente trabajo se muestra la factibilidad de la construcci��n de una bomba de ��mbolo para el transporte de hormig��n, con una granulometr��a m��xima de 8 mm; a partir de un cilindro de di��metro interior 90 mm y 400 mm de longitud, para ser accionada por un motor el��ctrico monof��sico de 2.2 kW de potencia y 1730 rpm. Se realiza el an��lisis de la variaci��n de la presi��n requerida para el bombeo y la potencia necesaria, en funci��n del di��metro interior del conducto; concluy��ndose que debe estar entre 40 y 50 mm, para cumplir con los requerimientos del cliente.

Rivulinae. Monophyly of Rivulinae is supported by eight synapomorphies (Costa, 2011a): 1. ventral process of the angulo-articular narrow and triangular shaped (Fig. 3 b-c); 2. interhyal bone rudimentary or absent; 3. first epibranchial twisted (Fig. 4a); 4. subdistal process of the second epibranchial absent (Fig. 4a); 5. uncinate process of the third epibranchial forming an angle of about 45���60�� (Fig. 4a); 6. paired process on the first vertebra anteriorly directed; 7. membrane between preopercular laterosensory series and isthmus continuous; 8. E-scales not overlapped. Other combined (Costa, 2013); and molecular phylogenies (Murphy, Collier, 1996; Murphy et al., 1999; Hrbek et al., 2004; Vermeulen, Hrbek, 2005; Furness et al., 2015; Pohl et al., 2015) support the monophyly of Rivulinae., Published as part of Loureiro, Marcelo, S��, Rafael de, Serra, Sebasti��n W., Alonso, Felipe, Lan��s, Luis Esteban Krause, Volcan, Matheus Vieira, Calvi��o, Pablo, Nielsen, Dalton, Duarte, Alejandro & Garcia, Graciela, 2018, Review of the family Rivulidae (Cyprinodontiformes, Aplocheiloidei) and a molecular and morphological phylogeny of the annual fish genus Austrolebias Costa 1998, pp. 1-20 in Neotropical Ichthyology 16 (3) on page 3, DOI: 10.1590/1982-0224-20180007, http://zenodo.org/record/3709839, {"references":["Costa WJEM. Phylogenetic position and taxonomic status of Anablepsoides, Atlantirivulus, Cynodonichthys, Laimosemion, and Melanorivulus (Cyprinodontiformes: Rivulidae). Ichthyol Explor Freshw. 2011 a; 22 (3): 233 - 49.","Costa WEJM. Historical biogeography of Aplocheiloid killifishes (Teleostei: Cyprinodontiformes). Vertebr Zool. 2013; 63 (2): 139 - 54.","Murphy WJ, Collier GE. Phylogenetic relationships within the aplocheiloid fish genus Rivulus (Cyprinodontiformes, Rivulidae): Implications for Caribbean and Central American biogeography. Mol Biol Evol. 1996; 13 (5): 642 - 49.","Murphy WJ, Thomerson, JE, Collier GE. Phylogeny of the Neotropical killifish family Rivulidae (Cyprinodontiformes, Aplocheiloidei) inferred from mitochondrial DNA sequences. Mol Phylogenet Evol. 1999; 13 (2): 289 - 301.","Hrbek T, Deus CP, Farias IP. Rivulus duckensis (Teleostei; Cyprinodontiformes): New species from the Taruma basin of Manaus, Amazonas, Brazil, and its relationships to other Neotropical Rivulidae. Copeia. 2004; (3): 569 - 76.","Vermeulen FBN, Hrbek T. Kryptolebias sepia n. sp. (Actinopterygii: Cyprinodontiformes: Rivulidae), a new killifish from the Tapanahony River drainage in southeast Surinam. Zootaxa. 2005; 928 (1): 1 - 20.","Furness AI, Reznick DN, Springer MS, Meredith RW. Convergent evolution of alternative developmental trajectories associated with diapause in African and South American killifish. Proc R Soc B Biol Sci. 2015; 282 (1802): 20142189.","Pohl M, Milvertz FC, Meyer A, Vences M. Multigene phylogeny of Cyprinodontiform fishes suggests continental rediations and a rogue taxon position of Pantanodon. Vertebr Zool. 2015; 65 (1): 37 - 44."]}

Millerichthys Costa. Monotypic ((M. robustus (Miller & Hubbs)) small-sized (30 mm SL), annual genus, that is distributed in southern Mexico. The species is diagnosed by the following apomorphies: reduced mesopterygoid; conical and elongate ventral process of posttemporal; long posterior series of supraorbital neuromasts; absence of transverse dark bar crossing the eye; three transverse yellow stripes on the anal fin of males; and black spots along the caudal-fin base of females (Costa, 1998). Its phylogenetic relationship with other Rivulidae remains unclear. Costa (1998), proposed three synapomorphies to support the sister relationship of Millerichthys Costa with Rachoviini: a dorsally pointed preopercle, reduced neural prezygapophyses of caudal vertebrae, and a reduced dark pigmentation in females. However, Costa (2004) hypothesized the genus as the sister taxon of Cynolebiasinae based on three different synapomorphies: mesopterygoid small, posterior tip not contacting metapterygoid; hypurals completely fused; frontal scales in transverse pattern without distinct central scale., Published as part of Loureiro, Marcelo, S��, Rafael de, Serra, Sebasti��n W., Alonso, Felipe, Lan��s, Luis Esteban Krause, Volcan, Matheus Vieira, Calvi��o, Pablo, Nielsen, Dalton, Duarte, Alejandro & Garcia, Graciela, 2018, Review of the family Rivulidae (Cyprinodontiformes, Aplocheiloidei) and a molecular and morphological phylogeny of the annual fish genus Austrolebias Costa 1998, pp. 1-20 in Neotropical Ichthyology 16 (3) on page 6, DOI: 10.1590/1982-0224-20180007, http://zenodo.org/record/3709839, {"references":["Costa WJEM. Phylogeny and classification of Rivulidae revisited: Origin and evolution of annualism and miniaturization in rivulid fishes (Cyprinodontiformes: Aplocheiloidei). J Comp Biol. 1998; 3: 33 - 94."]}

Kryptolebiasinae. This is a clade composed by a single genus with seven valid non-annual species, distributed in theAtlantic coastal basins and estuaries from Florida (USA) to southern Brazil. Three androdioecius species conform a monophyletic unit within the genus (Vermeulen, Hrbek, 2005; Costa et al., 2010) that inhabit mangroves; two of them with clear evidence of self-fertilization (Tatarenkov et al., 2011). Costa (2004) proposed two synapomorphies for Kryptolebias: a dorsally expanded flange on dorsal tip of the autopalatine (Fig. 1a) and a vestigial or absent anterodorsal process of urohyal (Fig. 2a)., Published as part of Loureiro, Marcelo, S��, Rafael de, Serra, Sebasti��n W., Alonso, Felipe, Lan��s, Luis Esteban Krause, Volcan, Matheus Vieira, Calvi��o, Pablo, Nielsen, Dalton, Duarte, Alejandro & Garcia, Graciela, 2018, Review of the family Rivulidae (Cyprinodontiformes, Aplocheiloidei) and a molecular and morphological phylogeny of the annual fish genus Austrolebias Costa 1998, pp. 1-20 in Neotropical Ichthyology 16 (3) on page 3, DOI: 10.1590/1982-0224-20180007, http://zenodo.org/record/3709839, {"references":["Vermeulen FBN, Hrbek T. Kryptolebias sepia n. sp. (Actinopterygii: Cyprinodontiformes: Rivulidae), a new killifish from the Tapanahony River drainage in southeast Surinam. Zootaxa. 2005; 928 (1): 1 - 20.","Costa WJEM, Lima SMQ, Bartolette R. Androdioecy in Kryptolebias killifish and the evolution of self-fertilizing hermaphroditism. Biol J Linn Soc. 2010; 99 (2): 344 - 49.","Tatarenkov A, Lima SMQ, Avise JC. Extreme homogeneity and low genetic diversity in Kryptolebias ocellatus from south-eastern Brazil suggest a recent foundation for this androdioecious fish population. J Fish Biol. 2011; 79 (7): 2095 - 105."]}

Prorivulus Costa. A monotypic non-annual genus, P. auriferus Costa, Lima & Suzart, from the coastal drainages of northeastern Brazil, is diagnosed by the presence of soft anal fin rays in females, minute urogenital papilla in males, and absence of a dark bar on iris. It has some morphological characteristics similar to Kryptolebias, but other characters more closely align with the rest of Rivulidae. According to the original description it would be the sister taxa of all Rivulidae except Kryptolebias (Costa, 2004b, 2006a). Unfortunately, it has never been included in any subsequent phylogeny or revision, and its position remains uncertain., Published as part of Loureiro, Marcelo, S��, Rafael de, Serra, Sebasti��n W., Alonso, Felipe, Lan��s, Luis Esteban Krause, Volcan, Matheus Vieira, Calvi��o, Pablo, Nielsen, Dalton, Duarte, Alejandro & Garcia, Graciela, 2018, Review of the family Rivulidae (Cyprinodontiformes, Aplocheiloidei) and a molecular and morphological phylogeny of the annual fish genus Austrolebias Costa 1998, pp. 1-20 in Neotropical Ichthyology 16 (3) on page 6, DOI: 10.1590/1982-0224-20180007, http://zenodo.org/record/3709839, {"references":["Costa WEJM. A new killifish genus and species from the coastal plains of northeastern Brazil (Teleostei: Cyprinodontiformes: Rivulidae). Zootaxa. 2004 b; 642 (1): 1 - 10.","Costa WEJM. Relationships and taxonomy of the killifish genus Rivulus (Cyprinodontiformes: Aplocheiloidei: Rivulidae) from the Brazilian Amazonas river basin, with notes on historical ecology. Aqua. 2006 a; 11 (4): 133 - 45."]}

Cynolebiasinae. The monophyly of this subfamily, composed by small to large-sized annual species, is well supported presenting the following synapomorphies: dorsally positioned dorsomedial process of autopalatine; reduced mesopterygoid; thin C-shaped preopercle with reduced dorsal tip, median rim, and sensory canal (Fig. 1f); elongate epibranchials and interarcual cartilage (Fig. 4c); rounded second hypobranchial (Fig. 6d); absence of teeth in the fourth ceratobranchial; absence of a posteroventral process on the anterior portion of the fourth ceratobranchial; absence of teeth in vomer; thin lachrymal, with narrow lower portion and vestigial sensory canal; absence of dermosphenotic; absence of anterior processes of first vertebra; vestigial or absent neural prezygapophysis of caudal vertebrae (Fig. 7 c-d); narrow and anteriorly curved epural and parahypural (Fig. 7 c-d); anteriorly placed dorsal fin origin; reduced first proximal anal-fin radial; reduced ossification of medial anal-fin radials; vestigial or absent ventral process of posttemporal; elongate supracleithrum; scale-like pectoral radials (Fig. 8 b-c); cylindrical urogenital papilla in males; prominent pocket-like urogenital papilla in females; reduced supraorbital squamation; reduced caudal-fin squamation; continuous supraorbital series of neuromasts; long posterior series of supraorbital neuromasts; minute neuromast on dermosphenotic; and vertical bars on body sides of juveniles (Costa, 1998); Molecular phylogenies support this clade (Murphy et al., 1999; Hrbek, Larson, 1999; Costa, 2013; Furness et al., 2015; Pohl et al., 2015). The two clades that composed the subfamily, Cynopoecilini and Cynolebiasini, are also very well supported by morphological and molecular analyses., Published as part of Loureiro, Marcelo, S��, Rafael de, Serra, Sebasti��n W., Alonso, Felipe, Lan��s, Luis Esteban Krause, Volcan, Matheus Vieira, Calvi��o, Pablo, Nielsen, Dalton, Duarte, Alejandro & Garcia, Graciela, 2018, Review of the family Rivulidae (Cyprinodontiformes, Aplocheiloidei) and a molecular and morphological phylogeny of the annual fish genus Austrolebias Costa 1998, pp. 1-20 in Neotropical Ichthyology 16 (3) on page 7, DOI: 10.1590/1982-0224-20180007, http://zenodo.org/record/3709839, {"references":["Costa WJEM. Phylogeny and classification of Rivulidae revisited: Origin and evolution of annualism and miniaturization in rivulid fishes (Cyprinodontiformes: Aplocheiloidei). J Comp Biol. 1998; 3: 33 - 94.","Murphy WJ, Thomerson, JE, Collier GE. Phylogeny of the Neotropical killifish family Rivulidae (Cyprinodontiformes, Aplocheiloidei) inferred from mitochondrial DNA sequences. Mol Phylogenet Evol. 1999; 13 (2): 289 - 301.","Hrbek T, Larson A. The evolution of diapause in the killifish family Rivulidae (Atherinomorpha Atherinomorpha, Cyprinodontiformes): A molecular phylogenetic and biogeographic perspective. Evolution. 1999; 53 (4): 1200 - 16.","Costa WEJM. Historical biogeography of Aplocheiloid killifishes (Teleostei: Cyprinodontiformes). Vertebr Zool. 2013; 63 (2): 139 - 54.","Furness AI, Reznick DN, Springer MS, Meredith RW. Convergent evolution of alternative developmental trajectories associated with diapause in African and South American killifish. Proc R Soc B Biol Sci. 2015; 282 (1802): 20142189.","Pohl M, Milvertz FC, Meyer A, Vences M. Multigene phylogeny of Cyprinodontiform fishes suggests continental rediations and a rogue taxon position of Pantanodon. Vertebr Zool. 2015; 65 (1): 37 - 44."]}

Laimosemion Huber. Composed by ca. twenty-nine small to medium-sized species (20-40 mm SL), widely distributed in northwestern South America. The genus lacks synapomorphies, and can be distinguished from other rivulines only by combination of characters, in particular an intense yellow or orange pigmentation of the anal fin in adult females. Monophyly is supported by molecular analyses (Hrbek et al., 2004; Costa 2011a, 2013). This is considered a non-annual genus; however, Furness et al. (2018) have found diapause stages in some species similar to those found in annual species, which could represent intermediates steps in the evolution of the annual life cycle., Published as part of Loureiro, Marcelo, S��, Rafael de, Serra, Sebasti��n W., Alonso, Felipe, Lan��s, Luis Esteban Krause, Volcan, Matheus Vieira, Calvi��o, Pablo, Nielsen, Dalton, Duarte, Alejandro & Garcia, Graciela, 2018, Review of the family Rivulidae (Cyprinodontiformes, Aplocheiloidei) and a molecular and morphological phylogeny of the annual fish genus Austrolebias Costa 1998, pp. 1-20 in Neotropical Ichthyology 16 (3) on page 6, DOI: 10.1590/1982-0224-20180007, http://zenodo.org/record/3709839, {"references":["Hrbek T, Deus CP, Farias IP. Rivulus duckensis (Teleostei; Cyprinodontiformes): New species from the Taruma basin of Manaus, Amazonas, Brazil, and its relationships to other Neotropical Rivulidae. Copeia. 2004; (3): 569 - 76.","Costa WJEM. Phylogenetic position and taxonomic status of Anablepsoides, Atlantirivulus, Cynodonichthys, Laimosemion, and Melanorivulus (Cyprinodontiformes: Rivulidae). Ichthyol Explor Freshw. 2011 a; 22 (3): 233 - 49.","Costa WEJM. Historical biogeography of Aplocheiloid killifishes (Teleostei: Cyprinodontiformes). Vertebr Zool. 2013; 63 (2): 139 - 54.","Furness AI, Reznick DN, Tatarenkov A, Avise JC. The evolution of diapause in Rivulus (Laimosemion). Zool J Linnean Soc [serial on the Internet]. 2018; 20: 1 - 18. Available from: http: // dx. doi. org / 10.1093 / zoolinnean / zly 021"]}

Neutron capture cross section measurements on$^{155}$Gd and$^{157}$Gd were performed using the time-of-flight technique at the n_TOF facility at CERN on isotopically enriched samples. The measurements were carried out in the n_TOF experimental area EAR1, at 185 m from the neutron source, with an array of 4 C$_{6}$D$_{6}$ liquid scintillation detectors. At a neutron kinetic energy of 0.0253 eV, capture cross sections of 62.2(2.2) and 239.8(8.4) kilobarn have been derived for$^{155}$Gd and$^{157}$Gd, respectively, with up to 6% deviation relative to values presently reported in nuclear data libraries, but consistent with those values within 1.6 standard deviations. A resonance shape analysis has been performed in the resolved resonance region up to 181 eV and 307 eV, respectively for$^{155}$Gd and$^{157}$Gd, where on average, resonance parameters have been found in good agreement with evaluations. Above these energies and up to 1 keV, the observed resonance-like structure of the cross section has been analysed and characterised. From a statistical analysis of the observed neutron resonances we deduced: neutron strength function of $2.01(28) \times 10^{-4}$ and $2.17(41) \times 10^{-4}$ , average total radiative width of 106.8(14) meV and 101.1(20) meV and s-wave resonance spacing 1.6(2) eV and 4.8(5) eV for n +$^{155}$Gd and n +$^{157}$Gd systems, respectively. Neutron capture cross section measurements on$^{155}$Gd and$^{157}$Gd were performed using the time-of-flight technique at the n_TOF facility at CERN on isotopically enriched samples. The measurements were carried out in the n_TOF experimental area EAR1, at 185 m from the neutron source, with an array of 4 C$_{6}$D$_{6}$ liquid scintillation detectors. At a neutron kinetic energy of 0.0253 eV, capture cross sections of 62.2(2.2) and 239.8(8.4) kilobarn have been derived for$^{155}$Gd and$^{157}$Gd, respectively, with up to 6% deviation relative to values presently reported in nuclear data libraries, but consistent with those values within 1.6 standard deviations. A resonance shape analysis has been performed in the resolved resonance region up to 181 eV and 307 eV, respectively for$^{155}$Gd and$^{157}$Gd, where on average, resonance parameters have been found in good agreement with evaluations. Above these energies and up to 1 keV, the observed resonance-like structure of the cross section has been analysed and characterised. From a statistical analysis of the observed neutron resonances we deduced: neutron strength function of $2.01(28) \times 10^{-4}$ and $2.17(41) \times 10^{-4}$, average total radiative width of 106.8(14) meV and 101.1(20) meV and s-wave resonance spacing 1.6(2) eV and 4.8(5) eV for n +$^{155}$Gd and n +$^{157}$Gd systems, respectively. Neutron capture measurements on $^{155}$Gd and $^{157}$Gd were performed using the time-of-flight technique at the n\_TOF facility at CERN. Four samples in form of self-sustaining metallic discs isotopically enriched in $^{155}$Gd and $^{157}$Gd were used. The measurements were carried out at the experimental area (EAR1) at 185 m from the neutron source, with an array of 4 C$_6$D$_6$ liquid scintillation detectors. The capture cross sections of $^{155}$Gd and $^{157}$Gd at neutron kinetic energy of 0.0253 eV have been estimated to be 62.2(2.2) kb and 239.8(9.3) kb, respectively, thus up to 6\% different relative to the ones reported in the nuclear data libraries. A resonance shape analysis has been performed in the resolved resonance region up to 180 eV and 300 eV, respectively, in average resonance parameters have been found in good agreement with evaluations. Above these energies the observed resonance-like structures in the cross section have been tentatively characterised in terms of resonance energy and area up to 1 keV.

Motivated by the construction of Bach flat neutral signature Riemannian extensions, we study the space of parallel trace free tensors of type $(1,1)$ on an affine surface. It is shown that the existence of such a parallel tensor field is characterized by the recurrence of the symmetric part of the Ricci tensor.

Background: $��$-delayed multiple neutron emission has been observed for some nuclei with A$\leq$100, with $^{100}$Rb being the heaviest $��$2n emitter measured to date. So far, only 25 P$_{2n}$ values have been determined for the $\sim$300 nuclei that may decay in this way. Accordingly, it is of interest to measure P$_{2n}$ values for the other possible multiple neutron emitters throughout the chart of the nuclides. It is of particular interest to make such measurement for nuclei with A$>$100 to test the predictions of theoretical models and simulation tools for the decays of heavy nuclei in the region of very neutron-rich nuclei. In addition, the decay properties of these nuclei are fundamental for the understanding of astrophysical nucleosynthesis processes such as the $r$-process, and safety inputs for nuclear reactors. Purpose: To determine for the first time the two neutron branching ratio, P$_{2n}$ value, for $^{136}$Sb through a direct neutron measurement, and to provide precise P$_{1n}$ values for $^{136}$Sb and $^{136}$Te. Method: Pure beams were provided by the JYFLTRAP at the IGISOL facility of the University of Jyv��skyl��, Finland. The purified ions were implanted into a moving tape at the end of the beam line. The detection setup consisted of a plastic scintillator placed right behind the implantation point, and the BELEN detector, based on neutron counters embedded in a polyethylene matrix. The analysis was based on the study of the $��$- and neutron- growth-and-decay curves and the $��$-one-neutron and $��$-two-neutron time correlations. Results: The P$_{2n}$ value of $^{136}$Sb was found to be 0.14(3)\% and the measured P$_{1n}$ values for $^{136}$Sb and $^{136}$Te were found to be 32.2(15)\% and 1.47(6)\%, respectively. The measured P$_{2n}$ value is a factor 44 smaller than predicted by the FRDM+QRPA model used for $r$-process calculations., 11 pages, 10 figures

$Background:$ Previous measurements of $��$-delayed neutron emitters comprise around 230 nuclei, spanning from the $^{8}$He up to $^{150}$La. Apart from $^{210}$Tl, with a minuscule branching ratio of 0.007\%, no other neutron emitter is measured yet beyond $A=150$. Therefore new data are needed, particularly in the heavy mass region around N=126, in order to guide theoretical models and to understand the formation of the third r-process peak at $A\sim195$. $Purpose:$ To measure both, $��$-decay half-lives and neutron branching ratios of several neutron-rich Au, Hg, Tl, Pb and Bi isotopes beyond $N=126$. $Method:$ Ions of interest are produced by fragmentation of a $^{238}$U beam, selected and identified via the GSI-FRS fragment separator. A stack of segmented silicon detectors (SIMBA) is used to measure ion-implants and $��$-decays. An array of 30 $^3$He tubes embedded in a polyethylene matrix (BELEN) is used to detect neutrons with high efficiency and selectivity. A self-triggered digital system is employed to acquire data and to enable time-correlations. The latter are analyzed with an analytical model and results for the half-lives and neutron-branching ratios are derived using the binned Maximum-Likelihood method. $Results:$ Twenty new $��$-decay half-lives are reported for $^{204-206}$Au, $^{208-211}$Hg,$^{211-216}$Tl,$^{215-218}$Pb and $^{218-220}$Bi, nine of them for the first time. Neutron emission probabilities are reported for $^{210,211}$Hg and $^{211-216}$Tl. $Conclusions:$ The new $��$-decay half-lives are in good agreement with previous measurements in this region. The measured neutron emission probabilities are comparable or smaller than values predicted by global models like RHB+RQRPA., 17 pages, 21 figures, will be submitted at PRC

BRIKEN is a complex detection system to be installed at the RIB-facility of the RIKEN Nishina Center. It is aimed at the detection of heavy-ion implants, $\beta$-particles, $\gamma$-rays and $\beta$-delayed neutrons. The whole detection setup involves the Advanced Implantation Detection Array (AIDA), two HPGe Clover detectors and a large set of 166 counters of 3He embedded in a high-density polyethylene matrix. This article reports on a novel methodology developed for the conceptual design and optimisation of the 3He-tubes array, aiming at the best possible performance in terms of neutron detection. The algorithm is based on a geometric representation of two selected parameters of merit, namely, average neutron detection efficiency and efficiency flatness, as a function of a reduced number of geometric variables. The response of the detection system itself, for each configuration, is obtained from a systematic MC-simulation implemented realistically in Geant4. This approach has been found to be particularly useful. On the one hand, due to the different types and large number of 3He-tubes involved and, on the other hand, due to the additional constraints introduced by the ancillary detectors for charged particles and gamma-rays. Empowered by the robustness of the algorithm, we have been able to design a versatile detection system, which can be easily re-arranged into a compact mode in order to maximize the neutron detection performance, at the cost of the gamma-ray sensitivity. In summary, we have designed a system which shows, for neutron energies up to 1(5) MeV, a rather flat and high average efficiency of 68.6%(64%) and 75.7%(71%) for the hybrid and compact modes, respectively. The performance of the BRIKEN system has been also quantified realistically by means of MC-simulations made with different neutron energy distributions.

We classify non-reductive four-dimensional homogeneous conformally Einstein manifolds., New version correcting some inaccuracies in the original paper

The $^{58}$Ni $(n,\gamma)$ cross section has been measured at the neutron time of flight facility n_TOF at CERN, in the energy range from 27 meV up to 400 keV. In total, 51 resonances have been analyzed up to 122 keV. Maxwellian averaged cross sections (MACS) have been calculated for stellar temperatures of kT$=$5-100 keV with uncertainties of less than 6%, showing fair agreement with recent experimental and evaluated data up to kT = 50 keV. The MACS extracted in the present work at 30 keV is 34.2$\pm$0.6$_\mathrm{stat}\pm$1.8$_\mathrm{sys}$ mb, in agreement with latest results and evaluations, but 12% lower relative to the recent KADoNIS compilation of astrophysical cross sections. When included in models of the s-process nucleosynthesis in massive stars, this change results in a 60% increase of the abundance of $^{58}$Ni, with a negligible propagation on heavier isotopes. The reason is that, using both the old or the new MACS, 58Ni is efficiently depleted by neutron captures., Comment: 10 pages, 8 figures, 5 tables

Physical Review C

Physical Review C

The β -decay of 187Re ( t 1 / 2 = 42.3 Gyr ) represents a suited cosmo-chronometer for the age of the r -process abundances, since the radiogenic part of the daughter isotope 187Os is defined by the difference between the solar 187Os abundance and s -process contribution to 187Os. The latter component can be determined via the s -process systematics based on the stellar neutron capture cross sections of 186Os and 187Os. The laboratory cross section of 187Os requires a significant correction for the effect of the low-lying excited state at 9.75 keV, which is strongly populated under stellar conditions. This theoretical correction can be improved by an experimental cross section for inelastic scattering to the 9.75 keV state. High resolution time-of-flight measurements of ( n , γ ) cross sections of 186,187,188Os from 1 eV to 1 MeV at CERN n_TOF facility are reported. The inferred stellar cross sections differ from previously recommended values. In addition, the inelastic scattering cross section has been measured at 30 keV neutron energy via time-of-flight at the Karlsruhe 3.7 MV Van de Graaff. The implications of these results for the Re/Os clock are discussed. Progress in Particle and Nuclear Physics

Babiano-Suárez, V., et al., i-TED is an innovative detection system which exploits Compton imaging techniques to achieve a superior signal-to-background ratio in (n, γ) cross-section measurements using time-of-flight technique. This work presents the first experimental validation of the i-TED apparatus for high-resolution time-of-flight experiments and demonstrates for the first time the concept proposed for background rejection. To this aim, the Au(n, γ) and Fe(n, γ) reactions were studied at CERN n_TOF using an i-TED demonstrator based on three position-sensitive detectors. Two CD detectors were also used to benchmark the performance of i-TED. The i-TED prototype built for this study shows a factor of ∼ 3 higher detection sensitivity than state-of-the-art CD detectors in the 10 keV neutron-energy region of astrophysical interest. This paper explores also the perspectives of further enhancement in performance attainable with the final i-TED array consisting of twenty position-sensitive detectors and new analysis methodologies based on Machine-Learning techniques., This work has been carried out in the framework of a project funded by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (ERC Consolidator Grant project HYMNS, with grant agreement No. 681740). The authors acknowledge support from the Spanish Ministerio de Ciencia e Innovación under grants PID2019-104714GB-C21, FPA2017-83946-C2-1-P, FIS2015-71688-ERC, CSIC for funding PIE-201750I26, and the funding agencies of the participating institutes. We would like to thank the crew at the Electronics Laboratory of IFIC, in particular Manuel Lopez Redondo and Jorge Nácher Arándiga for their excellent and efficient work.

Copper (Cu) and its based preparations have been used for over 200 years to control fungi and bacterial diseases in cultivated plants. Downy mildew caused by the obligate biotrophic oomycete Plasmopara viticola is one of the most relevant and recurrent diseases of grapevines. Recently, the use of Cu is being limited by some regulations because of its high impact at different levels (health and environmental problems). Due to its accumulation in soil, this metal causes a little controversy with the principles of sustainable production. Therefore, international legislation and initiatives have recently been arisen to start limiting its use, with the main goal to replace it. In this framework, some alternatives have been tested and others are recently being developed to replace, at least partially, the use of Cu in viticulture. Many of them, are being developed and tested under the scope of research and development EU funded projects. To not compromise sustainability targets in viticulture, results from these R&D projects need to be considered to assess the present risks of using Cu in viticulture and to better support establishing limits for its applications, considering soils vulnerability, while no sustainable alternatives are available in the market.