2,110 research outputs found
Ozone Measurements in the Mesosphere During a Solar Proton Event
Charged particle precipitation in the Earth's atmosphere produces odd nitrogen and odd hydrogen. These species take part in catalytic reactions which destroy atmospheric ozone in the stratosphere and mesosphere. Modeling efforts regarding the impact of these ionization events on the neutral atmosphere describe ozone depletions in good agreement with observations in the stratosphere and mesosphere. The photochemical effects of the solar proton event (SPE) of August 1972 are discussed, and calculations for higher altitudes (70 to 90 km) are presented that indicate after a brief reduction during and immediately following intense particle precipitation, ozone will later reach higher concentrations than those present before the event
The eta ' signal from partially quenched Wilson fermions
We present new results from our ongoing study of flavor singlet pseudoscalar
mesons in QCD. Our approach is based on (a) performing truncated eigenmode
expansions for the hairpin diagram and (b) incorporating the ground state
contribution for the connected meson propagator. First, we explain how the
computations can be substantially improved by even-odd preconditioning. We
extend previous results on early mass plateauing in the eta' channel of
two-flavor full QCD with degenerate sea and valence quarks to the partially
quenched situation. We find that early mass plateau formation persists in the
partially quenched situation.Comment: Lattice2002(spectrum), 3 pages, 5 figure
Snake Mind, Wolf Body, Panther Courage: Jojo Rabbit as a Critique of Hegemonic Masculinity
In 2019, the movie Jojo Rabbit (Waititi, 2019) was released to theaters. Because the film uses comedy and satire to tell a story about Jojo, a young Nazi who has Hitler as an imaginary friend, it received mix reviews. This analysis focuses on how the movie sheds light on the negative influence of hegemonic masculinity. Hegemonic masculinity refers to the messages and actions that place men above women or types of masculinity above femininity and other masculinities. Jojo’s desire to be a Nazi is deeply connected to his desire to be man. This analysis examines how hegemonic masculinity a) can limit the definition of manhood in negative ways b) pressures men and boys to prove or defend their manhood, and c) influences how boys and men use violence, threats, and public humiliation to police each one another’s masculinity. By understanding the film in this way, we can better understand how messages of hegemonic masculinity support extremist beliefs like white supremacy and neo-Nazism. We can also see how beliefs about male superiority harm everyone, even boys and men
Meson and Baryon dispersion relations with Brillouin fermions
We study the dispersion relations of mesons and baryons built from Brillouin
quarks on one N_f=2 gauge ensemble provided by QCDSF. For quark masses up to
the physical strange quark mass, there is hardly any improvement over the
Wilson discretization, if either action is link-smeared and tree-level clover
improved. For quark masses in the range of the physical charm quark mass, the
Brillouin action still shows a perfect relativistic behavior, while the Wilson
action induces severe cut-off effects. As an application we determine the
masses of the \Omega_c^0, \Omega_{cc}^+ and \Omega_{ccc}^{++} baryons on that
ensemble.Comment: 16 pages, 9 figures, 4 tables; v2: one Reference added, matches
published versio
Helicity Dependent and Independent Generalized Parton Distributions of the Nucleon in Lattice QCD
A complete description of the nucleon structure in terms of generalized
parton distributions (GPDs) at twist 2 level requires the
measurement/computation of the eight functions H, E, \tilde H, \tilde E, H_T,
E_T, \tilde H_T and \tilde E_T, all depending on the three variables x, \xi and
t. In this talk, we present and discuss our first steps in the framework of
lattice QCD towards this enormous task. Dynamical lattice QCD results for the
lowest three Mellin moments of the helicity dependent and independent GPDs are
shown in terms of their corresponding generalized form factors. Implications
for the transverse coordinate space structure of the nucleon as well as the
orbital angular momentum (OAM) contribution of quarks to the nucleon spin are
discussed in some detail.Comment: 5 pages, 5 figures, Talk presented by Ph.H. at Electron-Nucleus
Scattering VIII, Elba, Italy, June 21-25, 2004; typos corrected, minor change
in wording on p.4&
Transverse Structure of Nucleon Parton Distributions from Lattice QCD
This work presents the first calculation in lattice QCD of three moments of
spin-averaged and spin-polarized generalized parton distributions in the
proton. It is shown that the slope of the associated generalized form factors
decreases significantly as the moment increases, indicating that the transverse
size of the light-cone quark distribution decreases as the momentum fraction of
the struck parton increases.Comment: 4 pages, 1 figur
Calculation of the N to Delta electromagnetic transition matrix element
We present results on the ratio of electric quadrupole to magnetic dipole
amplitudes, , for the transition from lattice QCD. We consider both the quenched and the 2-flavor
theory.Comment: 3 pages, 4 figures, talk presented at Lattice2002(matrixel); Layout
of figures adjuste
transition form factors in Quenched and QCD
Calculations of the magnetic dipole, electric quadrupole and Coulomb
quadrupole amplitudes for the transition are presented
both in quenched QCD and with two flavours of degenerate dynamical quarks.Comment: Lattice2003(Matrix), 3 page
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