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The genus Paraphloeolaemus Thomas (Coleoptera: Cucujoidea: Laemophloeidae) is described for two new Neotropical species, P. vorticosus Thomas, new species, and P. pterosiagon Thomas, new species. Diagnoses and illustrations are provided.
The following 16 species are transferred from Laemophloeus Dejean (s. l.) to Phloeolaemus Casey: Phloeolaemus anticus (Sharp, 1899: 518) [= Laemophloeus anticus Sharp, 1899], new combination; Phloeolaemus boops (Sharp, 1899: 517) [= Laemophloeus boops Sharp, 1899], new combination; Phloeolaemus castaneipennis (Grouvelle, 1876: 494) [= Laemophloeus castaneipennis Grouvelle, 1876: 494], new combination; Phloeolaemus championi (Sharp, 1899: 516) [= Laemophloeus championi Sharp, 1899], new combination; Phloeolaemus curtus (Grouvelle, 1876: xxxiii) [= Laemophloeus curtus Grouvelle, 1876], new combination; Phloeolaemus endomychus (Sharp, 1899: 519) [= Laemophloeus endomychus Sharp, 1899], new combination; Phloeolaemus hoplites (Sharp, 1899: 517) [= Laemophloeus hoplites Sharp, 1899], new combination; Phloeolaemus ignobilis (Sharp, 1899: 518) [= Laemophloeus ignobilis Sharp, 1899], new combination; Phloeolaemus impressus (Grouvelle, 1876: xxxiii) [= Laemophloeus impressus Grouvelle, 1876], new combination; Phloeolaemus lacerdae (Grouvelle, 1877: 211) [= Laemophloeus lacerdae Grouvelle, 1877], new combination; Phloeolaemus macrocephalus (Schaeffer, 1910: 214) [= Laemophloeus macrocephalus Schaeffer, 1910], new combination; Phloeolaemus punctulaticollis (Hetschko, 1929: 94) [= Laemophloeus punctulaticollis Hetschko, 1929], new combination; Phloeolaemus reitteri (Grouvelle, 1877: 210) [= Laemophloeus reitteri Grouvelle, 1877], new combination; Phloeolaemus semiflavus (Grouvelle, 1876: 497) [= Laemophloeus semiflavus Grouvelle, 1876], new combination; Phloeolaemus sharpi (Hetschko, 1929: 41) [= Laemophloeus sharpi Hetschko, 1929], new combination; Phloeolaemus straminipennis (Reitter, 1876: 47) [= Laemophloeus straminipennis Reitter, 1876], new combination; Phloeolaemus teapensis (Grouvelle, 1876: 494) [= Laemophloeus teapensis Grouvelle, 1876], new combination.
The accurate knowledge of the neutron-induced fission cross-sections of actinides and other isotopes involved in the nuclear fuel cycle is essential for the design of advanced nuclear systems, such as Generation-IV nuclear reactors. Such experimental data can also provide the necessary feedback for the adjustment of nuclear model parameters used in the evaluation process, resulting in the further development of nuclear fission models. In the present work, the 240Pu(n,f) cross-section was measured at CERN's n_TOF facility relative to the well-known 235U(n,f) cross section, over a wide range of neutron energies, from meV to almost MeV, using the time-of-flight technique and a set-up based on Micromegas detectors. This measurement was the first experiment to be performed at n_TOF's new experimental area (EAR-2), which offers a significantly higher neutron flux compared to the already existing experimental area (EAR-1). Preliminary results as well as the experimental procedure, including a description of the facility and the data handling and analysis, are presented.
The 33S(n,α)30Si cross section measurement, using 10B(n,α) as reference, at the n_TOF Experimental Area 2 (EAR2) facility at CERN is presented. Data from 0.01 eV to 100 keV are provided and, for the first time, the cross section is measured in the range from 0.01 eV to 10 keV. These data may be used for a future evaluation of the cross section because present evaluations exhibit large discrepancies. The 33S(n,α)30Si reaction is of interest in medical physics because of its possible use as a cooperative target to boron in Neutron Capture Therapy (NCT).
New results are presented of the 234U neutron-induced fission cross section, obtained with high accuracy in the resonance region by means of two methods using the 235U(n,f) as reference. The recent evaluation of the 235U(n,f) obtained with SAMMY by L. C. Leal et al. (these Proceedings), based on previous n_TOF data [1], has been used to calculate the 234U(n,f) cross section through the 234U/235U ratio, being here compared with the results obtained by using the n_TOF neutron flux.
Species descriptions, keys to genera and species, and geographical distributions are presented for 43 species of the family Bruchidae (Coleoptera: Chrysomeloidea) for Chile. Of these species, seven are described as new:
Acanthoscelides aricae sp. nov., Lithraeus chillan sp. nov., L. comptus sp. nov., L. elguetai sp. nov., L. limari sp. nov., L. lonquimay sp. nov., and L. penai sp. nov. Eight species are endemic to Chile. A list of true host plants and floral records for those with known host associations is presented. Habitus photographs and drawings of pertinent body parts, including male genitalia, are provided. References pertaining to the previously described species are listed.
Neutron-induced reaction cross sections are important for a wide variety of research fields ranging from the study of nuclear level densities, nucleosynthesis to applications of nuclear technology like design, and criticality and safety assessment of existing and future nuclear reactors, radiation dosimetry, medical applications, nuclear waste transmutation, accelerator-driven systems and fuel cycle investigations. Simulations and calculations of nuclear technology applications largely rely on evaluated nuclear data libraries. The evaluations in these libraries are based both on experimental data and theoretical models. CERN’s neutron time-of-flight facility n_TOF has produced a considerable amount of experimental data since it has become fully operational with the start of its scientific measurement programme in 2001. While for a long period a single measurement station (EAR1) located at 185 m from the neutron production target was available, the construction of a second beam line at 20 m (EAR2) in 2014 has substantially increased the measurement capabilities of the facility. An outline of the experimental nuclear data activities at n_TOF will be presented.
The experimental area 2 (EAR-2) at CERNs neutron time-of-flight facility (n_TOF), which is operational since 2014, is designed and built as a short-distance complement to the experimental area 1 (EAR-1). The Parallel Plate Avalanche Counter (PPAC) monitor experiment was performed to characterize the beam pro↓le and the shape of the neutron 'ux at EAR-2. The prompt γ-flash which is used for calibrating the time-of-flight at EAR-1 is not seen by PPAC at EAR-2, shedding light on the physical origin of this γ-flash.
The Cosmological Lithium Problem refers to the large discrepancy between the abundance of primordial 7Li predicted by the standard theory of Big Bang Nucleosynthesis and the value inferred from the so-called “Spite plateau” in halo stars. A possible explanation for this longstanding puzzle in Nuclear Astrophysics is related to the incorrect estimation of the destruction rate of 7Be, which is responsible for the production of 95% of primordial Lithium. While charged-particle induced reactions have mostly been ruled out, data on the 7Be(n,α) and 7Be(n,p) reactions are scarce or completely missing, so that a large uncertainty still affects the abundance of 7Li predicted by the standard theory of Big Bang Nucleosynthesis. Both reactions have been measured at the n_TOF facility at CERN, providing for the first time data in a wide neutron energy range.
The transverse momentum distributions of the strange and double-strange hyperon resonances (Σ(1385)±, Ξ(1530)0) produced in p–Pb collisions at sNN−−−√=5.02 TeV were measured in the rapidity range −0.5<yCMS<0 for event classes corresponding to different charged-particle multiplicity densities, ⟨dNch/dηlab⟩. The mean transverse momentum values are presented as a function of ⟨dNch/dηlab⟩, as well as a function of the particle masses and compared with previous results on hyperon production. The integrated yield ratios of excited to ground-state hyperons are constant as a function of ⟨dNch/dηlab⟩. The equivalent ratios to pions exhibit an increase with ⟨dNch/dηlab⟩, depending on their strangeness content.
The transverse momentum distributions of the strange and double-strange hyperon resonances (Σ(1385)±, Ξ(1530)0) produced in p-Pb collisions at sNN−−−√=5.02 TeV were measured in the rapidity range −0.5<yCMS<0 for event classes corresponding to different charged-particle multiplicity densities, ⟨dNch/dηlab⟩. The mean transverse momentum values are presented as a function of ⟨dNch/dηlab⟩, as well as a function of the particle masses and compared with previous results on hyperon production. The integrated yield ratios of excited to ground-state hyperons are constant as a function of ⟨dNch/dηlab⟩. The equivalent ratios to pions exhibit an increase with ⟨dNch/dηlab⟩, depending on their strangeness content.