7,980 research outputs found
Gauge-mediated supersymmetry breaking with generalized messenger sector at LHC
We consider the generalized gauge mediated supersymmetry breaking (GMSB)
models with the messenger elds which do not form the complete multiplets of SU(5)
GUT symmetry. Such a situation may happen in the anomalous U(1) GUT scenario
because the mass spectrum of the superheavy particle does not respect SU(5) GUT
symmetry, although the success of the gauge coupling uni cation can be explained.
In this paper, we assume that one pair of the messenger elds gives the dominant
contribution, and the LHC signature for the two possible messengers, X + X and
Q + Q, are examined. We investigate the possibility to measure the deviation from
the usual GUT relation of the gaugino masses which is one of the most important
features of these scenarios.
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Visibility and aerosol measurement by diode-laser random-modulation CW lidar
Examples of diode laser (DL) random-modulation continuous wave (RM-CW) lidar measurements are reported. The ability of the measurement of the visibility, vertical aerosol profile, and the cloud ceiling height is demonstrated. Although the data shown here were all measured at night time, the daytime measurement is, of course, possible. For that purpose, accurate control of the laser frequency to the center frequency of a narrow band filter is required. Now a new system with a frequency control is under construction
Tensor networks and the numerical renormalization group
The full-density-matrix numerical renormalization group (NRG) has evolved as
a systematic and transparent setting for the cal- culation of thermodynamical
quantities at arbitrary temperatures within the NRG framework. It directly
evaluates the relevant Lehmann representations based on the complete basis sets
intro- duced by Anders and Schiller (2005). In addition, specific attention is
given to the possible feedback from low energy physics to high energies by the
explicit and careful construction of the full thermal density matrix, naturally
generated over a distribution of energy shells. Specific examples are given in
terms of spectral functions (fdmNRG), time-dependent NRG (tdmNRG), Fermi-Golden
rule calculations (fgrNRG), as well as the calculation of plain thermodynamic
expectation values. Furthermore, based on the very fact that, by its iterative
nature, the NRG eigenstates are naturally described in terms of matrix product
states, the language of tensor networks has proven enormously convenient in the
description of the underlying algorithmic procedures. This paper therefore also
provides a detailed introduction and discussion of the prototypical NRG
calculations in terms of their corresponding tensor networks.Comment: 20 pages, 11 figures (adapted from habilitation thesis
CEDM constraints on modified sfermion universality and spontaneous CP violation
We discuss the supersymmetric CP problem that arises when the sfermion soft
mass universality is modified. We place the 3rd generation SU(5) ten-plet
sfermion masses in the weak scale in view of the naturalness. The other
sfermion masses are assumed to be universal and a TeV scale in order to weaken
the flavor changing neutral current processes and electric dipole moment (EDM)
constraints. However this modification generically induces too large up quark
chromo-EDM (CEDM) via the weak scale stop loop. In order to suppress this CEDM,
we propose certain type of flavor structure where the parameters of the
up-(s)quark sector are real whereas those of the down-(s)quark and the charged
(s)lepton sectors are complex at the GUT scale. It is shown that, in this set
up, up quark CEDM can be suppressed within the range where the current and
future experiments have their sensitivity. We briefly illustrate the simple
realization of these particular forms of the modified sfermion universality
with real up-(s)quark sector by spontaneous CP violation in E SUSY GUT with
SU(2) flavor symmetry.Comment: Hg EDM bound updated, content modified, figure added, typos
corrected, references adde
Quantum critical behavior in heavily doped LaFeAsOH pnictide superconductors analyzed using nuclear magnetic resonance
We studied the quantum critical behavior of the second antiferromagnetic (AF)
phase in the heavily electron-doped high- pnictide, LaFeAsOH
by using As and H nuclear-magnetic-resonance (NMR) technique. In
the second AF phase, we observed a spatially modulated spin-density-wave-like
state up to =0.6 from the NMR spectral lineshape and detected a low-energy
excitation gap from the nuclear relaxation time of As. The
excitation gap closes at the AF quantum critical point (QCP) at . The superconducting (SC) phase in a lower-doping regime contacts the
second AF phase only at the AF QCP, and both phases are segregated from each
other. The absence of AF critical fluctuations and the enhancement of the
in-plane electric anisotropy are key factors for the development of
superconductivity.Comment: accepted in Phys. Rev.
Formulae for partial widths derived from the Lindblad equation
A method for calculating partial widths of auto-ionizing states is proposed.
It combines either a complex absorbing potential or exterior complex scaling
with the Lindblad equation. The corresponding classical rate equations are
reproduced, and the trace conservation inherent in the Lindblad equation
ensures that the partial widths sums up to the total width of the initial
auto-ionizing state
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