65,292 research outputs found
Spontaneous CP violation in the 3-3-1 model with right-handed neutrinos
We implement the mechanism of spontaneous CP violation in the 3-3-1 model
with right-handed neutrinos and recognize their sources of CP violation. Our
main result is that the mechanism works already in the minimal version of the
model and new sources of CP violation emerges as an effect of new physics at
energies higher than the electroweak scale.Comment: Major changes in the quark sector, electronic dipole moment of the
neutron was evaluated, accepted for publication in the physical review
Neutrino Mixing and the Minimal 3-3-1 Model
In the minimal 3-3-1 model charged leptons come in a non-diagonal basis.
Moreover the Yukawa interactions of the model lead to a non-hermitian charged
lepton mass matrix. In other words, the minimal 3-3-1 model presents a very
complex lepton mixing. In view of this we check rigorously if the possible
textures of the lepton mass matrices allowed by the minimal 3-3-1 model can
lead or not to the neutrino mixing required by the recent experiments in
neutrino oscillation.Comment: two references add, minor chages, accepted for publication in MPL
Comparison of solar radio and EUV synoptic limb charts during the present solar maximum
The present solar cycle is particular in many aspects: it had a delayed
rising phase, it is the weakest of the last 100 years, and it presents two
peaks separated by more than one year. To understand the impact of these
characteristics on the solar chromosphere and coronal dynamics, images from a
wide wavelength range are needed. In this work we use the 17~GHz radio
continuum, formed in the upper chromosphere and the EUV lines 304 and
171~{\AA}, that come from the transition region (He II) and the corona (Fe IX,
X), respectively. We analyze daily images at 304 and 171~{\AA} obtained by the
Atmospheric Imaging Assembly (AIA). The 17~GHz maps were obtained by the
Nobeyama Radioheliograph (NoRH). To construct synoptic limb charts, we
calculated the mean emission of delimited limb areas with 100" wide and angular
separation of . At the equatorial region, the results show an
hemispheric asymmetry of the solar activity. The northern hemisphere dominance
is coincident with the first sunspot number peak, whereas the second peak
occurs concurrently with the increase in the activity at the south. The polar
emission reflects the presence of coronal holes at both EUV wavelengths,
moreover, the 17~GHz polar brightenings can be associated with the coronal
holes. Until 2013, both EUV coronal holes and radio polar brightenings were
more predominant at the south pole. Since then they have not been apparent in
the north, but thus appear in the beginning of 2015 in the south as observed in
the synoptic charts. This work strengthens the association between coronal
holes and the 17~GHz polar brightenings as it is evident in the synoptic limb
charts, in agreement with previous case study papers. The enhancement of the
radio brightness in coronal holes is explained by the presence of bright
patches closely associated with the presence of intense unipolar magnetic
fields.Comment: 6 pages, 5 figures. Acccepted for publication in Astronomy &
Astrophysic
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