1,704 research outputs found
Standard Model Higgs Physics at a 4 TeV Upgraded Tevatron
We compute an array of Standard Model Higgs boson (\hsm) signals and
backgrounds for a possible upgrade of the Tevatron to E_{\rm cm}=4\tev.
Taking \mt\geq 140\gev, and assuming a total accumulated luminosity of
L=30\fbi, we find that a Standard Model Higgs boson with \mhsm\lsim 110\gev
could almost certainly be detected using the \wpm\hsm\rta l\nu b\anti b mode.
A Higgs boson with mass between \sim 120\gev and \sim 140\gev or above
\sim 230-250\gev almost certainly would not be seen. A Higgs boson with
\mhsm\sim 150\gev or 200\lsim\mhsm\lsim 230-250\gev has a decent chance of
being detected in the ZZ\rta 4l mode. There would also be some possibility of
discovering the \hsm in the WW\rta l\nu jj mode for 150\lsim\mhsm\lsim
200\gev. Finally, hints of an event excess in the WW\rta ll \nu\nu mode due
to the \hsm might emerge for 140\lsim\mhsm\lsim 180\gev. Given the
difficult nature of the Higgs boson signals for \mhsm values beyond the reach
of LEP-200, and the discontinuous \mhsm range that could potentially be
probed, justification of an upgrade of the Tevatron to 4\tev on the basis of
its potential for Standard Model Higgs boson discovery would seem
inappropriate.Comment: 21 pages; requires phyzzx.tex and tables.tex; full postscript file
including embedded figures available via anonymous ftp at ucdhep.ucdavis.edu
as [anonymous.gunion]4tev.ps, preprint UCD-94-1
A double parton scattering background to Higgs boson production at the LHC
The experimental capability of recognizing the presence of b quarks in
complex hadronic final states has addressed the attention towards final states
with b\bar{b} pairs for observing the production of the Higgs boson at the LHC,
in the intermediate Higgs mass range.We point out that double parton scattering
processes are going to represent a sizeable background to the process.Comment: 9 pages, 2 figure
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
Constraints on the Universal Varying Yukawa Couplings: from SM-like to Fermiophobic
Varying the Standard Model (SM) fermion Yukawa couplings universally by a
generic positive scale factor (), we study the phenomenological fit to
the current available experimental results for the Higgs boson search at hadron
colliders. We point out that the Higgs production cross section and its decay
branching ratio to can be varied oppositely by to make
their product almost invariant. Thus, our scenario and the SM Higgs are
indistinguishable in the inclusive channel. The current
measurements on direct Yukawa coupling strength in the
channel are not precise enough to fix the scale factor . The most
promising is the vector-boson-fusion channel in which the CMS has already
observed possible suppression effect on the Yukawa couplings. Further more, the
global fit of the experimental data can get the optimal value by
introducing a suppression factor on the SM Yukawa couplings.Comment: 16 pages, 12 figures, 5 tables, update analysis is supplemente
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 Higgs Boson Decays H\to f\bar{f}\gamma Beyond the Standard Model
Neutral Higgs boson radiative decays of the form h_0, H, A \to
f\bar{f}\gamma, in the light fermion limit $m_f->0, are calculated in the two
Higgs doublet model at one-loop level. Comparisons with the calculation within
the standard model are given, which indicates that these two models are
distinguishable in the decay mode fermion-antifermion -photon. Our results show
that the concerned process may stand as an implement to identify the Higgs
belongings in case there is a intermediate mass Higgs detected.Comment: 13 pages in Revtex, version to appear in Phys. Rev.
Window on Higgs Boson: Fourth Generation Decays Revisited
Direct and indirect searches of the Higgs boson suggest that 113 GeV
170 GeV is likely. With the LEP era over and the
Tevatron Run II search via arduous, we revisit a case where
or jets could arise via strong pair
production. In contrast to 10 years ago, the tight electroweak constraint on
-- (hence --) splitting reduces FCNC
, rates, making naturally competitive.
Such a "cocktail solution" is precisely the mix that could evade the CDF search
for , and the may well be lurking below the top. In
light of the Higgs program, this two-in-one strategy should be pursued.Comment: 4 pages, RevTex, 4 eps figures, One more figure, version to be
published in Phys. Rev.
at Hadron Colliders
We study the observability for a lepton flavor-changing decay of a Higgs
boson at hadron colliders. Flavor-changing couplings of a Higgs
boson exist at tree level in models with multiple Higgs doublets. The
coupling is particularly motivated by the favorable intepretation of
oscillation. We find that at the Tevatron Run II the unique
signature could serve as the Higgs discovery channel, surpassing
expectations for Higgs boson searches in the SM and in a large parameter region
of the MSSM. The sensitivity will be greatly improved at the LHC, beyond the
coverage at a muon collider Higgs factory.Comment: Version to appear in PR
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