659 research outputs found
Two-Higgs-doublet model with a color-triplet scalar: a joint explanation for top quark forward-backward asymmetry and Higgs decay to diphoton
The excess of top quark forward-backward asymmetry () reported by
the Tevatron and the enhancement of the Higgs decay to diphoton observed by the
LHC may point to a same origin of new physics. In this note we examined such
anomalies in the two-Higgs-doublet model with a color-triplet scalar. We found
that under current experimental constraints this model can simultaneously
explain both anomalies at level. Also, we examined the Higgs decay
and displayed its correlation with . We found
that unlike other models, this model predicts a special correlation between
and , i.e., the rate is highly
suppressed while the rate is enhanced. This behavior may help to
distinguish this model in the future high luminosity run of the LHC.Comment: 18pages, 4figures, references adde
Analysis of the Management System Innovation in Small and Medium Sized Family Enterprises of China
The family enterprise is one of the oldest forms of enterprise organization in the development of human history. In a way, the development of modern market economy equates the history of the evolution and collaborative of family enterprises. The growth of the family enterprises has now become a unique economic landscape in such a public ownership society in China. China is transitioning from a planned economy to a market economy, and the biggest change is actually the emergence of private enterprises groups. It’s by arriving less much, by arrive infirmly strength has made them one of the most dynamic components in Chinese economy. They not only active in both the urban and rural markets, meet the needs of people’s material and cultural life, ease the employment pressure, but also lay the important foundation of China’s market-oriented reform and participation in international market competition. The general development of family enterprise and its great contribution to China’s economy show that family enterprise as an ancient business system is still active and alive in the modern market economy. Nonetheless, it is not a perfect form of business organization compared with other organizational forms. Family enterprises, especially small and medium-sized family enterprises have also encountered some bottleneck and challenge in the development process, and the only way to get rid of the dilemma is the innovation of family enterprise management system. This paper at first expatiates on the concept of family enterprises, and then based on the study of its characteristics analyzes the present situation of Chinese family enterprise management system. Finally, this paper will find out the existing problems and reasons in the innovation of management system for small and medium-sized family enterprises, in order to put forward effective countermeasures
Interpreting the 750 GeV diphoton excess by the singlet extension of the Manohar-Wise Model
The evidence of a new scalar particle from the 750 GeV diphoton excess,
and the absence of any other signal of new physics at the LHC so far suggest
the existence of new colored scalars, which may be moderately light and thus
can induce sizable and couplings without resorting to
very strong interactions. Motivated by this speculation, we extend the
Manohar-Wise model by adding one gauge singlet scalar field. The resulting
theory then predicts one singlet dominated scalar as well as three kinds
of color-octet scalars, which can mediate through loops the and interactions. After fitting the model to the diphoton data at
the LHC, we find that in reasonable parameter regions the excess can be
explained at level by the process ,
and the best points predict the central value of the excess rate with
, which corresponds to a -value of . We also
consider the constraints from various LHC Run I signals, and we conclude that,
although these constraints are powerful in excluding the parameter space of the
model, the best points are still experimentally allowed.Comment: 19 pages, 3 figure
Constraining Top partner and Naturalness at the LHC and TLEP
We investigate indirect constraints on the top partner within the minimal
fermionic top partner model. By performing a global fit of the latest Higgs
data, measurements and the electroweak precision
observables we find that the top partner with the mass up to 830 GeV is
excluded at level. Our bound on the top partner mass is much stronger
than the bounds obtained from the direct searches at the LHC. Under the current
constraints the fine-tuning measure is less than 9% and the branching ratio of
is bounded between 14% and 25%. We also find that precise
measurements of Higgs couplings at 240 GeV TLEP will constrain the top partner
mass in multi-TeV region.Comment: 16 pages, references and discussions adde
Higgs pair production with SUSY QCD correction: revisited under current experimental constraints
We consider the current experimental constraints on the parameter space of
the MSSM and NMSSM. Then in the allowed parameter space we examine the Higgs
pair production at the 14 TeV LHC via ( is the 125 GeV
SM-like Higg boson) with one-loop SUSY QCD correction and compare it with the
production via . We obtain the following observations: (i) For the
MSSM the production rate of can reach 50 fb and thus can be
competitive with , while for the NMSSM has a much
smaller rate than due to the suppression of the
coupling; (ii) The SUSY-QCD correction to is sizable, which
can reach for the MSSM and for the NMSSM within the
region of the Higgs data; (iii) In the heavy SUSY limit (all soft mass
parameters become heavy), the SUSY effects decouple rather slowly from the
Higgs pair production (especially the process), which, for TeV and TeV, can enhance the production rate by a factor of
1.5 and 1.3 for the MSSM and NMSSM, respectively. So, the Higgs pair production
may be helpful for unraveling the effects of heavy SUSY.Comment: discussions and references added, accepted by JHE
A light Higgs scalar in the NMSSM confronted with the latest LHC Higgs data
In the Next-to-Minimal Supersymemtric Standard Model (NMSSM), one of the
neutral Higgs scalars (CP-even or CP-odd) may be lighter than half of the
SM-like Higgs boson. In this case, the SM-like Higgs boson h can decay into
such a light scalar pair and consequently the diphoton and ZZ signal rates at
the LHC will be suppressed. In this work, we examine the constraints of the
latest LHC Higgs data on such a possibility. We perform a comprehensive scan
over the parameter space of the NMSSM by considering various experimental
constraints and find that the LHC Higgs data can readily constrain the
parameter space and the properties of the light scalar, e.g., at 3
level this light scalar should be highly singlet dominant and the branching
ratio of the SM-like Higgs boson decay into the scalar pair should be less than
about 30%. Also we investigate the detection of this scalar at various
colliders. Through a detailed Monte Carlo simulation we find that under the
constraints of the current Higgs data this light scalar can be accessible at
the LHC-14 with an integrated luminosity over 300 fb.Comment: Accepted by JHE
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