Search results for "moment"
showing 10 items of 3027 documents
"Table 23" of "Studies of W boson plus jets production in p\bar{p} collisions at sqrt(s)=1.96 TeV"
2013
Differential production cross-section, normalized to the measured inclusive W boson cross-section, as a function of W boson pT for events with two or more jets produced in association with a W boson. First uncertainty is statistical, second uncertainty is systematic.
"Table 22" of "Studies of W boson plus jets production in p\bar{p} collisions at sqrt(s)=1.96 TeV"
2013
Differential production cross-section, normalized to the measured inclusive W boson cross-section, as a function of W boson pT for events with one or more jets produced in association with a W boson. First uncertainty is statistical, second uncertainty is systematic.
"Table 24" of "Studies of W boson plus jets production in p\bar{p} collisions at sqrt(s)=1.96 TeV"
2013
Differential production cross-section, normalized to the measured inclusive W boson cross-section, as a function of W boson pT for events with three or more jets produced in association with a W boson. First uncertainty is statistical, second uncertainty is systematic.
"Table 25" of "Studies of W boson plus jets production in p\bar{p} collisions at sqrt(s)=1.96 TeV"
2013
Differential production cross-section, normalized to the measured inclusive W boson cross-section, as a function of W boson pT for events with four or more jets produced in association with a W boson. First uncertainty is statistical, second uncertainty is systematic.
Properties of condensed spin-aligned atomic hydrogen from variational calculations
1979
The optimal Jastrow-type ground-state wave function of spin-aligned atomic hydrogen is calculated using the pair potential of Kolos and Wolniewicz. The optimization is performed by solving the Euler equation in the hypernetted chain approximation. Accurate energies as well as pair-distribution functions are obtained. The Bose-Einstein condensate fraction is evaluated from the one-particle momentum distribution. The pair distribution function is also used to obtain stability criteria for the system and minimal values for the aligning magnetic field are calculated at low densities. The resulting values of the minimal aligning fields are considerably higher than those obtained previously.
Vortices in rotating two-component boson and fermion traps
2010
Quantum liquids may carry angular momentum by the formation of vortex states. This is well known for Bose-Einstein condensates in rotating traps, and was even found to occur in quantum dots at strong magnetic fields. Here we consider a two-component quantum liquid, where coreless vortices and interlaced lattices of coreless vortices appear in a very similar way for fermions and bosons with repulsive two-body interactions. The ground states at given angular momentum, as well as the pair correlations for equal and different numbers of atoms in the two components, are studied. (C) 2009 Elsevier B.V. All rights reserved.
Direct 3D mapping of the Fermi surface and Fermi velocity.
2017
Time-of-flight momentum microscopy is developed. It enables direct three-dimensional mapping of the topology of the Fermi surface, identification of electron and hole pockets, and quantification of Fermi velocity as a function of wavevector.
Competition of Dzyaloshinskii-Moriya and Higher-Order Exchange Interactions in Rh/Fe Atomic Bilayers on Ir(111)
2018
Using spin-polarized scanning tunneling microscopy and density functional theory we demonstrate the occurrence of a novel type of noncollinear spin structure in $\mathrm{Rh}/\mathrm{Fe}$ atomic bilayers on Ir(111). We find that higher-order exchange interactions depend sensitively on the stacking sequence. For fcc-$\mathrm{Rh}/\mathrm{Fe}/\mathrm{Ir}(111)$, frustrated exchange interactions are dominant and lead to the formation of a spin spiral ground state with a period of about 1.5 nm. For hcp-$\mathrm{Rh}/\mathrm{Fe}/\mathrm{Ir}(111)$, higher-order exchange interactions favor an up-up-down-down ($\ensuremath{\uparrow}\ensuremath{\uparrow}\ensuremath{\downarrow}\ensuremath{\downarrow}$) s…
Laser-induced collective excitations in a two-component Fermi gas
2002
We consider the linear density response of a two-component (superfluid) Fermi gas of atoms when the perturbation is caused by laser light. We show that various types of laser excitation schemes can be transformed into linear density perturbations, however, a Bragg spectroscopy scheme is needed for transferring energy and momentum into a collective mode. This makes other types of laser probing schemes insensitive for collective excitations and therefore well suited for the detection of the superfluid order parameter. We show that for the special case when laser light is coupled between the two components of the Fermi gas, density response is always absent in a homogeneous system.
Heavy mass expansion, light-by-light scattering through pointlike quanta, and the anomalous magnetic moment of the muon
2003
Contributions from light-by-light scattering to ${(g}_{\ensuremath{\mu}}\ensuremath{-}2)/2,$ the anomalous magnetic moment of the muon, are mediated by the exchange of charged fermions or scalar bosons. Assuming large masses M, pointlike couplings for the virtual particles and employing the technique of large mass expansion, analytical results are obtained for virtual fermions and scalars in the form of a series in ${(m}_{\ensuremath{\mu}}{/M)}^{2}.$ This series is well convergent even for the case ${M=m}_{\ensuremath{\mu}}.$ For pointlike virtual fermions, the expansion confirms published analytical formulas. For virtual scalars, the result can be used to evaluate the contribution from poi…