16,496 research outputs found
Zero mode contribution in quarkonium correlators and in-medium properties of heavy quarks
We calculate the low energy contribution to quarkonium correlators in
Euclidean time in lattice QCD. This contribution was found to give the dominant
source of the temperature dependence of the correlators. We have found that the
low energy contribution is well described by a quasi-particle model and have
determined the effective temperature dependent heavy quark mass.Comment: Contribution to QM2008, 4 pages, LaTeX, uses iopart.cls, corrected
typo
Sample-specific and Ensemble-averaged Magnetoconductance of Individual Single-Wall Carbon Nanotubes
We discuss magnetotransport measurements on individual single-wall carbon
nanotubes with low contact resistance, performed as a function of temperature
and gate voltage. We find that the application of a magnetic field
perpendicular to the tube axis results in a large magnetoconductance of the
order of e^2/h at low temperature. We demonstrate that this magnetoconductance
consists of a sample-specific and of an ensemble-averaged contribution, both of
which decrease with increasing temperature. The observed behavior resembles
very closely the behavior of more conventional multi-channel mesoscopic wires,
exhibiting universal conductance fluctuations and weak localization. A
theoretical analysis of our experiments will enable to reach a deeper
understanding of phase-coherent one-dimensional electronic motion in SWNTs.Comment: Replaced with published version. Minor changes in tex
The charged lepton mass matrix and non-zero with TeV scale New Physics
We provide an explicit structure of the charged lepton mass matrix which is
2-3 symmetric except for a single breaking of this symmetry by the muon mass.
We identify a flavor symmetric limit for the mass matrices where the first
generation is decoupled from the other two in the charged lepton sector while
in the neutrino sector the third generation is decoupled from the first two
generations. The leptonic mixing in the symmetric limit can be, among other
structures, the bi-maximal (BM) or the tri-bimaximal (TBM) mixing. Symmetry
breaking effects are included both in the charged lepton and the neutrino
sector to produce corrections to the leptonic mixing and explain the recent
measurements. A model that extends the SM by three right handed
neutrinos, an extra Higgs doublet, and two singlet scalars is introduced to
generate the leptonic mixing.Comment: 28 pages, 24 figures. arXiv admin note: substantial text overlap with
arXiv:1111.307
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