44 research outputs found
Correlating and Decays with Four Generations
The long-awaited mode has finally been observed at rate
consistent with Standard Model, albeit lower by 1.2. There is some hint
for New Physics in the rarer decay, especially if the
currently 2.2-enhanced central value persists with more data. The
measurement of violating phase , via both
and modes, has reached Standard Model sensitivity. These
measurements stand major improvement when LHC enters Run 2. Concurrently, the
and modes are being pursued in
a similar time frame. We illustrate the possible correlations between New
Physics effects in these four modes, using the fourth generation as example.
While correlations may or may not exist in other New Physics models, the four
generation model can accommodate enhancements in both
and .Comment: 9 pages, 5 figures for V1; for V2 title modified, minor changes
performed to figures, part of contents revised to 7 pages, note added, one of
the authors' affiliation changed, accepted for the publication of PL
Flavor Changing Heavy Higgs Interactions at the LHC
A general two Higgs doublet model (2HDM) is adopted to study the signature of
flavor changing neutral Higgs (FCNH) decay ,
where could be a CP-even scalar () or a CP-odd pseudoscalar
(). Measurement of the light 125 GeV neutral Higgs boson () couplings
at the Large Hadron Collider (LHC) favor the decoupling limit or the alignment
limit of a 2HDM, in which gauge boson and diagonal fermion couplings of
approach Standard Model values. In such limit, FCNH couplings of are
naturally suppressed by a small mixing parameter , while
the off-diagonal couplings of heavier neutral scalars are sustained by
. We study physics background from dominant
processes with realistic acceptance cuts and tagging efficiencies. Promising
results are found for the LHC running at 13 or 14 TeV collision energies.Comment: 14 pages, 5 figures, to be published in Phys. Lett.
Constraining a Lighter Exotic Scalar via Same-sign Top
It was shown recently that, in two Higgs doublet models without
symmetry, extra Yukawa couplings such as , can fuel
enough violation for electroweak baryogenesis (EWBG). We revisit an old
proposal where a pseudoscalar has mass between and
thresholds. With small, it evades
constraints, where approximate alignment also helps. We find this scenario with
relatively light is not yet ruled out, and can
probe sizable at the LHC, giving access to the second mechanism of
EWBG provided by such models.Comment: matches with the published versio