6 resultados para Gómez Carrillo, Enrique, 1873-1927.
em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo
Resumo:
Microphilypnus Myers, 1927 is a genus with three nominal species (M. amazonicus and M. macrostoma from the lower Amazon basin, and M. ternetzi from Orinoco), and is among the most poorly studied groups of Neotropical fishes. In this paper, M. ternetzi and M. macrostoma are redescribed and validated and M. amazonicus is regarded as synonym of M. ternetzi. Also, a new species, M. acangaquara, is described from the lower Amazon.
Resumo:
We present measurements of Underlying Event observables in pp collisions at root s = 0 : 9 and 7 TeV. The analysis is performed as a function of the highest charged-particle transverse momentum p(T),L-T in the event. Different regions are defined with respect to the azimuthal direction of the leading (highest transverse momentum) track: Toward, Transverse and Away. The Toward and Away regions collect the fragmentation products of the hardest partonic interaction. The Transverse region is expected to be most sensitive to the Underlying Event activity. The study is performed with charged particles above three different p(T) thresholds: 0.15, 0.5 and 1.0 GeV/c. In the Transverse region we observe an increase in the multiplicity of a factor 2-3 between the lower and higher collision energies, depending on the track p(T) threshold considered. Data are compared to PYTHIA 6.4, PYTHIA 8.1 and PHOJET. On average, all models considered underestimate the multiplicity and summed p(T) in the Transverse region by about 10-30%.
Resumo:
The ALICE experiment at the LHC has studied J/psi production at mid-rapidity in pp collisions at root s = 7 TeV through its electron pair decay on a data sample corresponding to an integrated luminosity L-int = 5.6 nb(-1). The fraction of J/psi from the decay of long-lived beauty hadrons was determined for J/psi candidates with transverse momentum p(t) > 1,3 GeV/c and rapidity vertical bar y vertical bar < 0.9. The cross section for prompt J/psi mesons, i.e. directly produced J/psi and prompt decays of heavier charmonium states such as the psi(2S) and chi(c) resonances, is sigma(prompt J/psi) (p(t) > 1.3 GeV/c, vertical bar y vertical bar < 0.9) = 8.3 +/- 0.8(stat.) +/- 1.1 (syst.)(-1.4)(+1.5) (syst. pol.) mu b. The cross section for the production of b-hadrons decaying to J/psi with p(t) > 1.3 GeV/c and vertical bar y vertical bar < 0.9 is a sigma(J/psi <- hB) (p(t) > 1.3 GeV/c, vertical bar y vertical bar < 0.9) = 1.46 +/- 0.38 (stat.)(-0.32)(+0.26) (syst.) mu b. The results are compared to QCD model predictions. The shape of the p(t) and y distributions of b-quarks predicted by perturbative QCD model calculations are used to extrapolate the measured cross section to derive the b (b) over bar pair total cross section and d sigma/dy at mid-rapidity.
Resumo:
The genus Ecliptoides Tavakilian & Peñaherrera-Leiva, 2005, recently revised by Clarke (2009) to include three Bolivian species, is brought up-to-date by the inclusion of further South American species transferred from Eclipta Bates, 1873, and Odontocera Audinet-Serville, 1833. Three new species are described from Brazil: E. schmidi, E. tavakiliani, and E. hogani. Ommata eunomia var. rufula Melzer, 1934, and Ommata (Eclipta) plaumanni Fuchs, 1961, are revalidated and considered species of Ecliptoides. Species transferred from Eclipta to include Ecliptoides: E. bivitticollis (Fisher, 1952); E. eunomia (Newman, 1841); E. pilosipes (Peñaherrera-Leiva & Tavakilian, 2004); E. fanchonae (Tavakilian & Peñaherrera-Leiva, 2003); E. giuglarisi (Peñaherrera-Leiva & Tavakilian, 2004); E. vasconezi (Peñaherrera-Leiva & Tavakilian, 2004); E. vicina (Melzer, 1927); E. lauraceae (Peñaherrera-Leiva & Tavakilian, 2004); and E. bauhiniae (Peñaherrera-Leiva & Tavakilian, 2004). Species transferred from Odontocera to include Ecliptoides: O. quadrivittata Melzer, 1922; O. pusilla Gounelle, 1911; and O. monostigma (Bates, 1869). New synonymy: Ommata (Eclipta) collarti Fuchs, 1959 = Odontocera pusilla Gounelle, 1911 (= Ecliptoides pusillus). Lectotypes are designated for Ommata (Eclipta) vicina, and Ommata (Eclipta) collarti. New distribution records are provided for E. eunomia, E. pilosipes, E. plaumanni and E. fanchonae. A key to the species of Ecliptoides is given.