582 research outputs found
Higgs-strahlung in Abelian Extended Supersymmetric Standard Model
We analyze the Higgs production via the Higgs-strahlung process
in an Abelian Extended
Supersymmetric SM. We work in the large Higgs trilinear coupling driven minimum
of the potential, and find that the next-to-lightest Higgs cannot be produced
by this process. Other Higgs scalars, namely the lightest and the heaviest,
have cross sections comparable to that in the pure SM. It is found that the
present model has observable differences with the other popular model, NMSSM,
in the same type of minimum.Comment: 12 pages, 2 postscript figures. To appear in Phys. Lett.
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Safety culture in the nuclear versus non-nuclear organization
The importance of safety culture in the safe and reliable operation of nuclear organizations is not a new concept. The greatest barriers to this area of research are twofold: (1) the definition and criteria of safety culture for a nuclear organization and (2) the measurement of those attributes in an objective and systematic fashion. This paper will discuss a proposed resolution of those barriers as demonstrated by the collection of data across nuclear and non-nuclear facilities over a two year period
Subsurface Flows in and Around Active Regions with Rotating and Non-rotating Sunspots
The temporal variation of the horizontal velocity in subsurface layers
beneath three different types of active regions is studied using the technique
of ring diagrams. In this study, we select active regions (ARs) 10923, 10930,
10935 from three consecutive Carrington rotations: AR 10930 contains a
fast-rotating sunspot in a strong emerging active region while other two have
non-rotating sunspots with emerging flux in AR 10923 and decaying flux in AR
10935. The depth range covered is from the surface to about 12 Mm. In order to
minimize the influence of systematic effects, the selection of active and quiet
regions is made so that these were observed at the same heliographic locations
on the solar disk. We find a significant variation in both components of the
horizontal velocity in active regions as compared to quiet regions. The
magnitude is higher in emerging-flux regions than in the decaying-flux region,
in agreement with earlier findings. Further, we clearly see a significant
temporal variation in depth profiles of both zonal and meridional flow
components in AR 10930, with the variation in the zonal component being more
pronounced. We also notice a significant influence of the plasma motion in
areas closest to the rotating sunspot in AR 10930 while areas surrounding the
non-rotating sunspots in all three cases are least affected by the presence of
the active region in their neighborhood.Comment: Solar Physics (in press), includes 11 figure
A Supersymmetric Effective Chiral Lagrangian
We construct in a manifestly supersymmetric form the leading and subleading
terms in momentum for an effective supersymmetric chiral Lagrangian in terms of
complex pions and their superpartners. A soft supersymmetry breaking term is
included and below the supersymmetry breaking scale the Lagrangian reduces to
the usual bosonic chiral Lagrangian in terms of real pions.Comment: University of Southampton preprint no. SHEP 93/94-12 LATE
The Strange Parton Distribution of the Nucleon: Global Analysis and Applications
The strangeness degrees of freedom in the parton structure of the nucleon are
explored in the global analysis framework, using the new CTEQ6.5 implementation
of the general mass perturbative QCD formalism of Collins. We systematically
determine the constraining power of available hard scattering experimental data
on the magnitude and shape of the strange quark and anti-quark parton
distributions. We find that current data favor a distinct shape of the strange
sea compared to the isoscalar non-strange sea. A new reference parton
distribution set, CTEQ6.5S0, and representative sets spanning the allowed
ranges of magnitude and shape of the strange distributions, are presented. Some
applications to physical processes of current interest in hadron collider
phenomenology are discussed.Comment: 19 pages; revised version submitted to JHE
Meridional Circulation and Global Solar Oscillations
We investigate the influence of large-scale meridional circulation on solar
p-modes by quasi-degenerate perturbation theory, as proposed by
\cite{lavely92}. As an input flow we use various models of stationary
meridional circulation obeying the continuity equation. This flow perturbs the
eigenmodes of an equilibrium model of the Sun. We derive the signatures of the
meridional circulation in the frequency multiplets of solar p-modes. In most
cases the meridional circulation leads to negative average frequency shifts of
the multiplets. Further possible observable effects are briefly discussed.Comment: 14 pages, 5 figures, submittted to Solar Physics Topical Issue
"HELAS
Observation and Modeling of the Solar-Cycle Variation of the Meridional Flow
We present independent observations of the solar-cycle variation of flows
near the solar surface and at a depth of about 60 Mm, in the latitude range
. We show that the time-varying components of the meridional flow
at these two depths have opposite sign, while the time-varying components of
the zonal flow are in phase. This is in agreement with previous results. We
then investigate whether the observations are consistent with a theoretical
model of solar-cycle dependent meridional circulation based on a flux-transport
dynamo combined with a geostrophic flow caused by increased radiative loss in
the active region belt (the only existing quantitative model). We find that the
model and the data are in qualitative agreement, although the amplitude of the
solar-cycle variation of the meridional flow at 60 Mm is underestimated by the
model.Comment: To be published in Solar Physcis Topical Issue "Helioseismology,
Asteroseismology, and MHD Connections
Associated production of H^{\pm} and W^{\mp} in high-energy e+e- collisions in the Minimal Supersymmetric Standard Model
We study the associated production of the charged Higgs boson and W^{\pm}
gauge boson in high energy e+e- collisions in the Minimal Supersymmetric
Standard Model (MSSM). This associated production, which first arises at the
one loop level, offers the possibility of producing the charged Higgs boson at
the e+e- collider with mass more than half the center-of-mass energy, when the
charged Higgs pair production is kinematically forbidden. We present analytic
and numerical results for the cross section for e+e- --> W+ H- in the full
MSSM, taking into account the previously uncalculated contributions from
supersymmetric (SUSY) particles. We find that the contributions of the SUSY
particles enhance the cross section over most of SUSY parameter space,
especially when the SUSY particles are light, ~200 GeV. With favorable SUSY
parameters, at small tan beta, this process can yield more than ten
W^{\pm}H^{\mp} events for m_{H^{\pm}} <~ 350 GeV in 500 fb-1 at a 500 GeV e+e-
collider, or m_{H^{\pm}} <~ 600 GeV in 1000 fb-1 at a 1000 GeV collider. 80%
left-handed polarization of the e- beam improves these reaches to m_{H^{\pm}}
<~ 375 GeV and m_{H^{\pm}} <~ 670 GeV, respectively.Comment: v2: 21 pages, 9 figures, comments on Higgs search bounds and new
references added, and minor changes; v3: 23 pages, 11 figures, review of
literature moved from introduction to new Sec.5 and 2 plots added, references
added, typos corrected; v4: bug fixed in nu nubar H0 cross section (Fig.11),
version to appear in PR
Additional phases induced by the supersymmetric CP phases
The explicit CP violation in the MSSM radiatively induces a finite
unremovable alignment between the Higgs doublets. This additinal phase can be
as large as the original CP phases in certain portions of the MSSM parameter
space. Considering the specific case of the charginos, this additional phase is
shown to induce a conceivable amount of CP violation near the would--be CP
conserving points. Moreover, the CP violation in the absence of this phase is
smaller than the one in the presence of it, and the former can never compete
with the latter, however large is.Comment: 29 pp, 15 fig
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