38 research outputs found
Testing Higgs boson scenarios in the phenomenological NMSSM
There could be another scalar in nature quasi-degenerate with the observed
one (h125). This is possible in models such as the Next-to-Minimal
Supersymmetric Standard Model (NMSSM). The scenario(s) with a single Higgs
boson can be compared to that with multiple ones, all near 125 GeV. In order to
assess the extent to which the current set of collider, cold dark matter relic
density and direct detection limits are capable of discriminating these
scenarios, we perform, for the first-time, global fits of a weak-scale
phenomenological NMSSM with 26 free parameters using the nested sampling
implementation in PolyChord, a next-generation tool for Bayesian inference. The
analyses indicate that the data used shows a moderate tendency for supporting
the scenario with an additional scalar much lighter than h125 with mass
distribution centred below the W-boson mass.
More stringent constraints are, however, needed for decisive inference
regarding an additional Higgs boson with mass much less than or near 125 GeV.Comment: v3: major revisions, to appear in EPJ
Soft SUSY Breaking Terms for Chiral Matter in IIB String Compactifications
This paper develops the computation of soft supersymmetry breaking terms for
chiral D7 matter fields in IIB Calabi-Yau flux compactifications with
stabilised moduli. We determine explicit expressions for soft terms for the
single-modulus KKLT scenario and the multiple-moduli large volume scenario. In
particular we use the chiral matter metrics for Calabi-Yau backgrounds recently
computed in hep-th/0609180. These differ from the better understood metrics for
non-chiral matter and therefore give a different structure of soft terms. The
soft terms take a simple form depending explicitly on the modular weights of
the corresponding matter fields. For the large-volume case we find that in the
simplest D7 brane configuration, scalar masses, gaugino masses and A-terms are
very similar to the dilaton-dominated scenario. Although all soft masses are
suppressed by ln(M_P/m_{3/2}) compared to the gravitino mass, the
anomaly-mediated contributions do not compete, being doubly suppressed and thus
subdominant to the gravity-mediated tree-level terms. Soft terms are
flavour-universal to leading order in an expansion in inverse Kahler moduli.
They also do not introduce extra CP violating phases to the effective action.
We argue that soft term flavour universality should be a property of the
large-volume compactifications, and more generally IIB flux models, in which
flavour is determined by the complex structure moduli while supersymmetry is
broken by the Kahler moduli. For the simplest large-volume case we run the soft
terms to low energies and present some sample spectra and a basic
phenomenological analysis.Comment: 40 pages, 9 figures, JHEP style; v2. sentence rephrase
Light dark matter around 100 GeV from the inert doublet model
We made global fits of the inert Higgs doublet model (IDM) in the light of
collider and dark matter search limits and the requirement for a strongly
first-order electroweak phase transition (EWPT). These show that there are
still IDM parameter spaces compatible with the observational constraints
considered. In particular, the data and theoretical requirements imposed favour
the hypothesis for the existence of a scalar dark matter candidate around 100
GeV. This is mostly due to the pull towards lower masses by the EWPT
constraint. The impact of electroweak precision measurements, the dark matter
direct detection limits, and the condition for obtaining a strongly enough
first-order EWPT, all have strong dependence, sometimes in opposing directions,
on the mass splittings between the IDM scalars.Comment: v2: minor revision, accepted for publication at EPJ
Linguistic security of Arabic in the context of globalization
In the context of globalization, security is required for the survival of a language and its native culture, just as language itself has become an important means of providing security for its native and non-native speakers, and Arabic is a living case. Security for Arabic is essential due to the great impact of globalization which is a source of concern for the Arabs, and security with Arabic is as equally essential for non-Arabs in their interaction with the Arab government, people and culture, as it is vital for the security of the Arabs themselves. This paper investigates the modes of relationship between language and security, and analyzes points of concern in the context of globalization for providing security "for Arabic" and "with Arabic"
Isolation and Identification of Phenol-Degrading Bacteria from Oil-Contaminated Sites
This work is aimed at isolating and identifying phenol-degrading bacteria from oil-contaminated sites. Five soil samples from three auto-mechanic workshops within Katsina metropolis were collected. The samples were analyzed by selective enrichment technique, which resulted in the isolation of four bacterial species. The species were further subjected to the Vitek 2 compact microbiological system analysis. Cupriavidus pauculus, Pontoea spp, Proteus mirabilis 1 and Proteus mirabilis 2 were identified. Result from the present study showed that the bacteria could utilize phenol as their carbon source. Proteus mirabilis 1 and Proteus mirabilis 2 showed lower phenol degradation potential, under similar conditions. Cupriavidus pauculus and Pontoea sp. showed significant increases (p<0.05) in their optical densities. The optical density increment is strongly correlated with increase in colony forming units of the bacteria. This study further showed that the isolates could tolerate high phenol concentrations and may serve as strong putative isolates in bioremediation of phenol-contaminated sites