14,394 research outputs found
Light pseudoscalar eta and H->eta eta decay in the simplest little Higgs mode
The SU(3) simplest little Higgs model in its original framework without the
so-called mu term inevitably involves a massless pseudoscalar boson eta, which
is problematic for b-physics and cosmological axion limit. With the mu term
introduced by hand, the eta boson acquires mass m_eta ~ mu, which can be
lighter than half the Higgs boson mass in a large portion of the parameter
space. In addition, the introduced mu term generates sizable coupling of
H-eta-eta. The Higgs boson can dominantly decay into a pair of eta's especially
when mH below the WW threshold. Another new decay channel of H->Z+eta can be
dominant or compatible with H -> WW for mH above the Z+eta threshold. We show
that the LEP bound on the Higgs boson mass is loosened to some extent due to
this new H->eta eta decay channel as well as the reduced coupling of H-Z-Z. The
Higgs boson mass bound falls to about 110 GeV for f=3-4 TeV. Since the eta
boson decays mainly into a bb pair, H-> eta eta -> 4b and H-> Z eta -> Z bb
open up other interesting search channels in the pursuit of the Higgs boson in
the future experiments. We discuss on these issues.Comment: major modification considering the simplest little Higgs model with
the mu ter
Improving Whole Slide Segmentation Through Visual Context - A Systematic Study
While challenging, the dense segmentation of histology images is a necessary
first step to assess changes in tissue architecture and cellular morphology.
Although specific convolutional neural network architectures have been applied
with great success to the problem, few effectively incorporate visual context
information from multiple scales. With this paper, we present a systematic
comparison of different architectures to assess how including multi-scale
information affects segmentation performance. A publicly available breast
cancer and a locally collected prostate cancer datasets are being utilised for
this study. The results support our hypothesis that visual context and scale
play a crucial role in histology image classification problems
One-dimensional vertical dust strings in a glass box
The oscillation spectrum of a one-dimensional vertical dust string formed
inside a glass box on top of the lower electrode in a GEC reference cell was
studied. A mechanism for creating a single vertical dust string is described.
It is shown that the oscillation amplitudes, resonance frequencies, damping
coefficients, and oscillation phases of the dust particles separate into two
distinct groups. One group exhibits low damping coefficients, increasing
amplitudes and decreasing resonance frequencies for dust particles closer to
the lower electrode. The other group shows high damping coefficients but
anomalous resonance frequencies and amplitudes. At low oscillation frequencies,
the two groups are also separated by a {\pi}-phase difference. One possible
cause for the difference in behavior between the two groups is discussed
A protocol for Agrobacterium-mediated transformation of Kalanchoë blossfeldiana with a flavonoid 3',5' hydroxylase (F3'5'H) gene
In the present investigation, explants from Kalanchoë blossfeldiana were used for gene transformation. The young leaves were inoculated with Agrobacterium tumefaciens LBA4404 strain with a binary vector plasmid pArtblue containing F3'5'H gene under control of CaMV35S promoter and nptII selectable marker gene. After inoculation, the explants were transferred to the co-cultivation medium. They were then transferred to the selection medium containing kanamycin and were sub-cultured every two weeks. Leaves of the putative transgenic shoots that survived in the selection medium were used in reverse transcription polymerase chain reaction (RT-PCR) analysis to detect gene expression. The RT-PCR analysis showed the presence of 550 bp F3'5'H amplification products and had an expression of F3'5'H gene. Plants with the introduced F3'5'H gene produced totally pale red flowers.Key words: Kalanchoë blossfeldiana, Agrobacterium-mediated transformation, young leaf, F3'5'H gene, reverse transcription-polymerase chain reaction (RT-PCR)
New Results for Diffusion in Lorentz Lattice Gas Cellular Automata
New calculations to over ten million time steps have revealed a more complex
diffusive behavior than previously reported, of a point particle on a square
and triangular lattice randomly occupied by mirror or rotator scatterers. For
the square lattice fully occupied by mirrors where extended closed particle
orbits occur, anomalous diffusion was still found. However, for a not fully
occupied lattice the super diffusion, first noticed by Owczarek and Prellberg
for a particular concentration, obtains for all concentrations. For the square
lattice occupied by rotators and the triangular lattice occupied by mirrors or
rotators, an absence of diffusion (trapping) was found for all concentrations,
except on critical lines, where anomalous diffusion (extended closed orbits)
occurs and hyperscaling holds for all closed orbits with {\em universal}
exponents and . Only one point on these critical lines can be related to a
corresponding percolation problem. The questions arise therefore whether the
other critical points can be mapped onto a new percolation-like problem, and of
the dynamical significance of hyperscaling.Comment: 52 pages, including 18 figures on the last 22 pages, email:
[email protected]
Evolution equations of curvature tensors along the hyperbolic geometric flow
We consider the hyperbolic geometric flow introduced by Kong and Liu [KL]. When the Riemannian
metric evolve, then so does its curvature. Using the techniques and ideas of
S.Brendle [Br,BS], we derive evolution equations for the Levi-Civita connection
and the curvature tensors along the hyperbolic geometric flow. The method and
results are computed and written in global tensor form, different from the
local normal coordinate method in [DKL1]. In addition, we further show that any
solution to the hyperbolic geometric flow that develops a singularity in finite
time has unbounded Ricci curvature.Comment: 15 page
High-Energy emissions from the Pulsar/Be binary system PSR J2032+4127/MT91 213
PSR J2032+4127 is a radio-loud gamma-ray-emitting pulsar; it is orbiting
around a high-mass Be type star with a very long orbital period of 25-50years,
and is approaching periastron, which will occur in late 2017/early 2018. This
system comprises with a young pulsar and a Be type star, which is similar to
the so-called gamma-ray binary PSR~B1259-63/LS2883. It is expected therefore
that PSR J2032+4127 shows an enhancement of high-energy emission caused by the
interaction between the pulsar wind and Be wind/disk around periastron. Ho et
al. recently reported a rapid increase in the X-ray flux from this system. In
this paper, we also confirm a rapid increase in the X-ray flux along the orbit,
while the GeV flux shows no significant change. We discuss the high-energy
emissions from the shock caused by the pulsar wind and stellar wind interaction
and examine the properties of the pulsar wind in this binary system. We argue
that the rate of increase of the X-ray flux observed by Swift indicates (1) a
variation of the momentum ratio of the two-wind interaction region along the
orbit, or (2) an evolution of the magnetization parameter of the pulsar wind
with the radial distance from the pulsar. We also discuss the pulsar wind/Be
disk interaction at the periastron passage, and propose the possibility of
formation of an accretion disk around the pulsar. We model high-energy
emissions through the inverse-Compton scattering process of the
cold-relativistic pulsar wind off soft photons from the accretion disk.Comment: 18 pages, 23 figures, 1 Table, accepted for publication in Ap
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