3,418 research outputs found
-meson anomalies and Higgs physics in flavored model
We consider a simple extension of the Standard Model with flavor-dependent
, that has been proposed to explain some of -meson anomalies recently
reported at LHCb. The charge is chosen as a linear combination of
anomaly-free and . In this model, the flavor structure
in the SM is restricted due to flavor-dependent charges, in particular,
quark mixings are induced by a small vacuum expectation value of the extra
Higgs doublet. As a result, it is natural to get sizable flavor-violating
Yukawa couplings of heavy Higgs bosons involving the bottom quark. In this
article, we focus on the phenomenology of the Higgs sector of the model
including extra Higgs doublet and singlet scalars. We impose various bounds on
the extended Higgs sector from Higgs and electroweak precision data, -meson
mixings and decays as well as unitarity and stability bounds, then discuss the
productions and decays of heavy Higgs bosons at the LHC.Comment: 40 pages, 11 figures, 1 table; v2: references added; v3: accepted
version for publication in EPJ
Supersymmetric Higgs-portal and X-ray lines
We consider a Dirac singlet fermion as thermal dark matter for explaining the
X-ray line in the context of a supersymmetric Higgs-portal model or a
generalized Dirac NMSSM. The Dirac singlet fermion gets a mass splitting due to
their Yukawa couplings to two Higgs doublets and their superpartners,
Higgsinos, after electroweak symmetry breaking. We show that a correct relic
density can be obtained from thermal freeze-out, due to the co-annihilation
with Higgsinos for the same Yukawa couplings. We discuss the phenomenology of
the Higgsinos in this model such as displaced vertices at the LHC.Comment: 15 pages, 4 figures, references adde
Cluster X-ray line at from axion-like dark matter
The recently reported X-ray line signal at
from a stacked spectrum of various galaxy clusters and the Andromeda galaxy may
be originating from a decaying dark matter particle of the mass . A
light axion-like scalar is suggested as a natural candidate for dark matter and
its production mechanisms are closely examined. We show that the right amount
of axion relic density with the preferred parameters, and , can be naturally obtainable
from the decay of inflaton. If the axions were produced from the saxion decay,
it could not have constituted the total relic density due to the bound from
structure formation. Nonetheless, the saxion decay is an interesting
possibility, because the line and dark radiation can be
addressed simultaneously, being consistent with the Planck data. Small
misalignment angles of the axion, ranging between depending on the reheating temperature, can also be the source of
axion production. The model with axion misalignment can satisfy the constraints
for structure formation and iso-curvature perturbation.Comment: 14 pages, significant changes in the form, matched to the journal
versio
Diboson Excesses Demystified in Effective Field Theory Approach
We study the collider implication of a neutral resonance which decays to
several diboson final states such as , , and via a
minimal set of effective operators. We consider both CP-even and CP-odd bosonic
states with spin 0, 1, or 2. The production cross sections for the bosonic
resonance states are obtained with the effective operators involving gluons
(and quarks), and the branching fractions are obtained with the operators
responsible for the interactions with electroweak gauge bosons. We demonstrate
that each scenario allows for a broad parameter space which could accommodate
the recently-reported intriguing excesses in the ATLAS diboson final states,
and discuss how the CP states and spin information of the resonance can be
extracted at the LHC run II.Comment: 22 pages, 6 figures, main text slightly modified with results
unchange
Flavor and CP-violating Higgs sector in two Higgs doublet models with
We investigate the role of a local symmetry for the problem of CP
violation in the effective theory for two Higgs doublet models and its
microscopic counterparts. First, in two Higgs doublet models with , we
show that the higher-dimensional operators in the scalar potential violate the
CP symmetry with an interplay with the mixing mass parameter, giving rise to
small mixings between CP-even and CP-odd scalars. Motivated by the -meson
anomalies in recent years, we take the flavored to be a benchmark model
for specifying the flavor structure. Then, we calculate the electric dipole
moment of electron (eEDM) at two loops due to the CP-violating
higher-dimensional operators and identify the correlation between the masses of
heavy Higgs bosons and the cutoff scale from the bound on eEDM. We also comment
on the possibility of making an independent test of the CP violation in the
collider searches for heavy Higgs bosons. Finally, we show how the obtained
eEDM results in the effective theory can be used to constrain microscopic
models with an explicit CP violation in the partially decoupled or dark
sectors.Comment: 37 pages, 5 figures, Journal versio
Gender and Measuring-position Differences in the Radial Pulse of Healthy Individuals
AbstractIn this research, radial pulse differences according to gender and measuring positions in healthy individuals were investigated in an objective manner. A total of 372 healthy volunteers (189 males and 183 females) participated in this study. The radial pulse was measured at six different measuring positions using a multistep tonometry system. The pulse data were compared between males and females and between different measuring positions. Compared to the pulses in females, those in males were deeper and slower, with a longer diastolic proportion and a shorter systolic proportion. Amplitude of the radial pulse increased as it went distal. The pulse was deepest at the Cheock position and shallowest at the Gwan position. Compared to the right pulse, the radial augmentation index was higher and the main peak angle was larger in case of the left pulse. The results of this research show that the radial pulses in healthy individuals differ significantly according to gender and measuring positions
A User Commitment Approach to Information Systems Infusion
Many organizations have huge investments on information systems (IS) but are unable to achieve the maximum benefits expected. The IS infusion stage refers to the state of using IS to its full potential. IS infusion is a form of organizational citizenship behavior because full utilization of IS requires extra-role behaviors (i.e., IS use beyond the mandated usage) beyond intra-role behaviors (i.e., mandated IS usage). As commitment is a key driver of organizational citizenship behavior, IS infusion requires the user’s commitment to IS usage. This study investigates the development of user commitment from the socio-technical system design perspective and the effect of user commitment on IS infusion. We identified five constructs from the socio-technical system design (job fit, task competence, technology competence, self-determination with technology, and self-determination with task). A survey of 236 enterprise system users showed that user commitment has a positive effect on IS infusion. User commitment, in turn, is influenced by job fit, technology competence, and self-determination with task. This study contributes to IS infusion research by introducing the development of user commitment from the socio-technical system design perspective. Managers can promote user commitment in order to reach the infusion stage of fully utilizing information systems
Electronic interferometer capacitively coupled to a quantum dot
We theoretically study electron interference in a ballistic electronic
interferometer capacitively coupled to a quantum dot. The visibility of the
interference is reduced when the dot has degenerate ground states with
different excess charges. The degree of the reduction depends on system
parameters such as the strength of the capacitive coupling, and the dependence
is analyzed in the regime where the dwell time of electrons in the dot is much
longer than the electron flight time through the interferometry region coupled
to the dot. The result is consistent with recent experimental data.Comment: 4 pages, 2 figure
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