366 research outputs found
Quark-Lepton Quartification
We propose that quarks and leptons are interchangeable entities in the
high-energy limit. This naturally results in the extension of [SU(3)]^3
trinification to [SU(3)]^4 quartification. In addition to the unbroken color
SU(3)_q of quarks, there is now also a color SU(3)_l of leptons which reduces
to an unbroken SU(2)_l. We discuss the natural occurrence of SU(2)_l doublets
at the TeV energy scale, which leads remarkably to the unification of all gauge
couplings without supersymmetry. Proton decay occurs through the exchange of
scalar bosons, with a lifetime in the range 10^{34} - 10^{36} years.Comment: 12 pages, 4 figures. Reference adde
New physics effects on top quark spin correlation and polarization at the LHC: a comparative study in different models
Extensions of the Standard Model often predict new chiral interactions for
top quark, which will contribute to top quark spin correlation and polarization
in production at the LHC. In this work, under the constraints from
the current Tevatron measurements, a comparative study of the spin correlation
and polarization is performed in three new physics models: the minimal
supersymmetric model without R-parity (RPV-MSSM), the third-generation enhanced
left-right model and the axigluon model. We find that the polarization
asymmetry may be enhanced to the accessible level in all these models while the
correction to the spin correlation may be detectable in the axigluon model and
the RPV-MSSM with couplings.Comment: Version in PRD (figs updated and discussions added
Is Work and Aging Research a Science of Questionnaires? Moving the Field Forward by Considering Perceived Versus Actual Behaviors
Research on work and aging predominantly relies on self-report data to create new insights relevant to individuals, organizations, and society. Whereas surveys and interviews based on self-reports offer a valuable inward-directed perspective on individuals and their understanding of others, they can only provide limited knowledge on the behaviors of employees at different ages and in age-diverse settings. This is because what employees actually do is often considerably different from their survey-based reports of what they or others do. In this commentary, we challenge the field to move beyond a science of questionnaires by complementing survey research with behavioral data. First, this would allow scholars to identify when and how behaviors accurately translate into surveyed perceptions of behaviors. Second, such an approach can advance our understanding of the micro-dynamics occurring in age-diverse workforces that ultimately manifest in emerging phenomena (e.g., age-inclusive climate, psychological safety perceptions, or group affective tone). Lastly, studying concrete and specific behaviors also allows scholars to develop better interventions and provide meaningful recommendations for practice that differentiate actual from perceived behaviors
Associated Production of Higgs and Weak Bosons, with H -> b\bar b, at Hadron Colliders
We consider the search for the Higgs boson at a high-luminosity Fermilab
Tevatron, an upgraded Tevatron of energy 3.5 TeV, and the CERN Large Hadron
Collider, via production followed by H -> bb~ and leptonic decay of the
weak vector bosons. We show that each of these colliders can potentially
observe the standard Higgs boson in the intermediate-mass range, 80 GeV <m_H <
120 GeV. This mode complements the search for and the study of the
intermediate-mass Higgs boson via H -> \gamma\gamma at the LHC. In addition, it
can potentially be used to observe the lightest Higgs scalar of the minimal
supersymmetric model in a region of parameter space not accessible to CERN LEP
II or the LHC (using h -> \gamma\gamma,ZZ^*).Comment: (changed the analysis of ZH production and the figures for susy), 17
pages + 7 figures, ILL-(TH)-94-8, BNL-6034
Single top or bottom production associated with a scalar in \gamma p collision as a probe of topcolor-assisted technicolor
In the framework of the topcolor-assisted technicolor (TC2) models, we study
the productions of a single top or bottom quark associated with a scalar in
\gamma-p collision, which proceed via the subprocesses c\gamma -> t\pi_t^0,
c\gamma -> t h_t^0 and c\gamma -> b\pi^+_t mediated by the anomalous top or
bottom coupling tc\pi_t^0, tch_t^0 and bc\pi_t^+. These productions, while
extremely suppressed in the Standard Model, are found to be significantly
enhanced in the large part of the TC2 parameter space, especially the
production via c\gamma -> b\pi^+ can have a cross section of 100 fb, which may
be accessible and allow for a test of the TC2 models.Comment: 13 pages, 4 figures, comments and references adde
Effects of R-parity violating supersymmetry in top pair production at linear colliders with polarized beams
In the minimal supersymmetric standard model with R-parity violation, the
lepton number violating top quark interactions can contribute to the top pair
production at a linear collider via tree-level u-channel squark exchange
diagrams. We calculate such contributions and find that in the allowed range of
these R-violating couplings, the top pair production rate as well as the top
quark polarization and the forward-backward asymmetry can be significantly
altered. By comparing the unpolarized beams with the polarized beams, we find
that the polarized beams are more powerful in probing such new physics.Comment: 10 pages, 6 fig
QCD and Yukawa corrections to single-top-quark production via q qbar -> t bbar
We calculate the O(alpha_s) and O(alpha_W m_t^2/M_W^2) corrections to the
production of a single top quark via the weak process q qbar -> t bbar at the
Fermilab Tevatron and the CERN Large Hadron Collider. An accurate calculation
of the cross section is necessary in order to extract |V_tb| from experiment.Comment: LaTeX, 13 pages, replaced with version to appear in Phys. Rev.
Radiative Corrections to W and Quark Propagators in the Resonance Region
We discuss radiative corrections to W and quark propagators in the resonance
region, |s-M^2| \lsim M*Gamma. We show that conventional mass renormalization,
when applied to photonic or gluonic corrections, leads in next to leading order
(NLO) to contributions proportional to [M*Gamma/(s-M^2)]^n, (n=1,2...), i.e. to
a non-convergent series in the resonance region, a difficulty that affects all
unstable particles coupled to massless quanta. A solution of this problem,
based on the concepts of pole mass and width, is presented. It elucidates the
issue of renormalization of amplitudes involving unstable particles and
automatically circumvents the problem of apparent on-shell singularities. The
roles of the Fried-Yennie gauge and the Pinch Technique prescription are
discussed. Because of special properties of the photonic and gluonic
contributions, and in contrast with the Z case, the gauge dependence of the
conventional on-shell definition of mass is unbounded in NLO. The evaluations
of the width in the conventional and pole formulations are compared and shown
to agree in NLO but not beyond.Comment: 19 pages, 7 figures, LaTeX (uses epsfig). Slight rewording of the
abstract and one of the sentences of the text. Minor misprints corrected. To
appear in Phys. Rev.
Single top production associated with a neutral scalar at LHC in topcolor-assisted technicolor
The topcolor-assisted technicolor (TC2) model predicts a number of neutral
scalars like the top-pion () and the top-Higgs (). These
scalars have flavor-changing neutral-current (FCNC) top quark couplings, among
which the top-charm transition couplings may be sizable. Such FCNC couplings
induce single top productions associated with a neutral scalar at the CERN
Large Hadron Collider (LHC) through the parton processes and
. In this note we examine these productions and find their
production rates can exceed the sensitivity of the LHC in a large
part of parameter space. Since in the Standard Model and the minimal
supersymmetric model such rare productions have unobservably small production
rates at the LHC, these rare processes will serve as a good probe for the TC2
model.Comment: 7 pages, 3 fig
Single-Top-Quark Production via W-Gluon Fusion at Next-to-Leading Order
Single-top-quark production via W-gluon fusion at hadron colliders provides
an opportunity to directly probe the charged-current interaction of the top
quark. We calculate the next-to-leading-order corrections to this process at
the Fermilab Tevatron, the CERN Large Hadron Collider, and DESY HERA. Using a
b-quark distribution function to sum collinear logarithms, we show that there
are two independent corrections, of order 1/[ln(m_t^2/m_b^2)] and alpha_s. This
observation is generic to processes involving a perturbatively derived
heavy-quark distribution function at an energy scale large compared with the
heavy-quark mass.Comment: 19 pages, 9 figures, small update to Phys. Rev. D versio
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