1,151 research outputs found
Dark Matter in Universal Extra Dimension Models: vrs
We show that in a class of universal extra dimension models (UED), which
solves both the neutrino mass and proton decay problem, an admixture of KK
photon and KK right handed neutrinos can provide the required amount of cold
dark matter (CDM). This model has two parameters and ( is
the radius of the extra space dimensions and the extra neutral gauge boson
of the model). Using the value of the relic CDM density, combined with the
results from the cryogenic searches for CDM, we obtain upper limits on
of about 400-650 GeV and TeV, both being accessible to LHC. In
some regions of the parameter space, the dark matter-nucleon scattering cross
section can be as high as of cm, which can be probed by the next
round of dark matter search experiments.Comment: 13 pages, 2 figures; minor changes; to appear in Phys. Rev.
Unified TeV Scale Picture of Baryogenesis and Dark Matter
We present a simple extension of MSSM which provides a unified picture of
cosmological baryon asymmetry and dark matter. Our model introduces a gauge
singlet field and a color triplet field which couple to the
right--handed quark fields. The out--of equilibrium decay of the Majorana
fermion mediated by the exchange of the scalar field generates adequate
baryon asymmetry for GeV and TeV. The scalar partner
of (denoted ) is naturally the lightest SUSY particle as it
has no gauge interactions and plays the role of dark matter.
annihilates into quarks efficiently in the early universe via the exchange of
the fermionic field. The model is experimentally testable in (i)
neutron--antineutron oscillations with a transition time estimated to be around
sec, (ii) discovery of colored particles at LHC with mass of
order TeV, and (iii) direct dark matter detection with a predicted cross
section in the observable range.Comment: 10 pages, one reference updated. Version to appear in Phys. Rev. Let
Kinerja Portofolio Saham pada Perusahaan Makanan, Property dan Pertambangan di Bursa Efek Indonesia
The Stock Portfolios' Performance of Food, Property, and Mining IndustryThis research aimed to analyze the Portfolio's performance of food industry, property, and mining. There are three parameters, namely: Sharpe Performance, Traynor Performance, and Jensen Performance. The three performance measurements assume that there is a linear connection between the return portfolios with the return of some market index. During the period, 2009 to 2013, and the mining and gas sub-sector are more productive than the other sub-sectors. The mining sector is better than the Property Sector and the Food Sector. Then based on the method of Jensen ALPHA it showed the highest performance group of mining stocks, in proportion to the risk which is also very high. The study suggests that the existing has to be maintained and further improved so that the mission to develop sources of potential energy into a profitable investment portfolio can sustain.DOI: 10.15408/ess.v7i2.535
Neutrino Mixing and Leptogenesis in Symmetry
We study the consequences of the -symmetry behind the --
universality in neutrino mass matrix. We then implement this symmetry in the
type-I seesaw mechanism and show how it can accommodate all sorts of lepton
mass hierarchies and generate enough lepton asymmetry to interpret the observed
baryon asymmetry in the universe. We also show how a specific form of a
high-scale perturbation is kept when translated via the seesaw into the low
scale domain, where it can accommodate the neutrino mixing data. We finally
present a realization of the high scale perturbed texture through addition of
matter and extra exact symmetries.Comment: 29 pages, 1 figure, 3 tables. Complete re-analysis. Version to appear
in PR
Reconciling the CAST and PVLAS Results
The PVLAS experiment has recently claimed evidence for an axion-like particle
in the milli-electron-Volt mass range with a coupling to two photons that
appears to be in contradiction with the negative results of the CAST experiment
searching for solar axions. The simple axion interpretation of these two
experimental results is therefore untenable and it has posed a challenge for
theory. We propose a possible way to reconcile these two results by postulating
the existence of an ultralight pseudo-scalar particle interacting with two
photons and a scalar boson and the existence of a low scale phase transition in
the theory.Comment: 4 pages, 2 figures; references update
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