38,610 research outputs found
In-situ Determination of the ATLAS Muon Performance
The ATLAS detector allows for the precise and efficient reconstruction of muons. Muon
tracks are reconstructed with 97% efficiency with a momentum resolution of approximately 2-3%
over most of the kinematic range and better than 10% for transverse momenta up to 1 TeV and
|η| <2.7. We present methods to measure the performance of the muon identification during the
operation of the ATLAS detector using muons from Z and J/ψdecays
On the renormalization procedure for quantum fields with modified dispersion relation in curved spacetimes
We review our recent results on the renormalization procedure for a free
quantum scalar field with modified dispersion relations in curved spacetimes.
For dispersion relations containing up to powers of the spatial momentum,
the subtraction necessary to renormalize depends
on . We first describe our previous analysis for spatially flat
Friedman-Robertson-Walker and Bianchi type I metrics. Then we present a new
power counting analysis for general background metrics in the weak field
approximation.Comment: Talk given at the 7th Alexander Friedmann International Seminar on
Gravitation and Cosmology, Joao Pessoa, Brazil, July 200
CP violation in semileptonic tau lepton decays
The leading order contribution to the direct CP asymmetry in tau^{+/-} ->
K^{+/-} pi^0 nu_{tau} decay rates is evaluated within the Standard Model. The
weak phase required for CP violation is introduced through an interesting
mechanism involving second order weak interactions, which is also responsible
for tiny violations of the Delta S= Delta Q rule in K_{l3} decays. The
calculated CP asymmetry turns out to be of order 10^{-12}, leaving a large
window for studying effects of non-standard sources of CP violation in this
observable.Comment: 5 pages, 3 figures, version published in Phys.Rev.
Scattering theory of nonlinear thermoelectric transport
We investigate nonlinear transport properties of quantum conductors in
response to both electrical and thermal driving forces. Within scattering
approach, we determine the nonequilibrium screening potential of a generic
mesoscopic system and find that its response is dictated by particle and
entropic injectivities which describe the charge and entropy transfer during
transport. We illustrate our model analyzing the voltage and thermal
rectification of a resonant tunneling barrier. Importantly, we discuss
interaction induced contributions to the thermopower in the presence of large
temperature differences.Comment: 5 pages, 3 figures; slightly shortened version to fulfill the
journal's requirement
Beyond the soft photon approximation in radiative production and decay of charged vector mesons
We study the effects of model-dependent contributions and the electric
quadrupole moment of vector mesons in the decays and
. Their interference with the amplitude originating
from the radiation due to electric charges vanishes for photons emitted
collinearly to the charged particle in the final state. This brings further
support to our claim in previous works, that measurements of the photon energy
spectrum for nearly collinear photons in those decays are suitable for a first
measurement of the magnetic dipole moment of charged vector mesons.Comment: 13 pages, 2 eps figures, Latex. Accepted for publication in Journal
of Physics G: Nuclear and Particle Physics(2001
Anti-Queer Microaggressions Towards Queer Black Men
Microaggressions are reoccurring derogatory messages that degrade and/ or discredit one’s identity. While invisible and unknown to many, they remain visible and apparent to those impacted by them. The research questions for this project are: (1) What microaggressions do Queer Black men experience within larger society? (2) To contrast with larger society, what microaggressions do Queer Black men experience within Black communities? By conducting focus groups, I will examine the intersectional microaggressions that Queer Black males experience in their own community, as well as document microaggression that they experience in larger society. After conducting my focus groups, I will be adopting Derald Wing Sue’s taxonomy of microaggression themes to translate the underlying messages behind delivered microaggressions. The results in this study will aide in addressing an appeared gap within microaggression literature by, documenting how Queer Black males experience these muted, normalized insults and invalidations in societ
Series expansions for the third incomplete elliptic integral via partial fraction decompositions
We find convergent double series expansions for Legendre's third incomplete
elliptic integral valid in overlapping subdomains of the unit square. Truncated
expansions provide asymptotic approximations in the neighbourhood of the
logarithmic singularity if one of the variables approaches this point
faster than the other. Each approximation is accompanied by an error bound. For
a curve with an arbitrary slope at our expansions can be rearranged
into asymptotic expansions depending on a point on the curve. For reader's
convenience we give some numeric examples and explicit expressions for
low-order approximations.Comment: The paper has been substantially updated (hopefully improved) and
divided in two parts. This part is about third incomplete elliptic integral.
10 page
Comment on `Strong Vortex Liquid Correlation' from Multiterminal Measurements on Untwinned YBaCuO Single Crystals'
A.Rydh and \"O.Rapp [Phys. Rev. Lett. {\bf 86}, 1873 (2001).] claim that the
vortex liquid in untwinned YBaCuO crystals is correlated
above the melting transition, in striking contrast to previous work [D.L\'opez
{\it et al.}, Phys. Rev. Lett. {\bf 76}, 4034 (1996).]. In this Comment we
present new measurements using the same experimental technique on twinned and
untwinned YBaCuO crystals with similar overall
characteristics as those reported by Rydh and Rapp . The comparison of the
vortex correlation response in both cases indicates that the central conclusion
of their work is not correct. Our results reconfirm the work by L\'opez {\it et
al.} and points on the origin of the misinterpretation in the work of Rydh and
Rapp.Comment: comment on A.Rydh and \"O.Rapp, Phys. Rev. Lett. {\bf 86}, 1873
(2001). accepted in Phys. Rev. Let
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