5,126 research outputs found
Like-sign dilepton signature for gluino production at LHC including top quark and higgs boson effects
A systematic analysis of the like-sign dipleton signature for gluino
production at LHC is performed in the -conserving minimal supersymmetric
standard model, taking into account the top quark and Higgs boson effects in
the cascade decay. We consider two representative values of the gluino mass,
300 and 800 GeV, along with those of the other SUSY parameters. While the top
quark contribution is kinematically suppressed for the former case it is very
import for the latter. Ways of separating the signal from the background are
discussed. One expects a viable LSD signals upto a gluino mass of
(1200) GeV at the low (high) luminosity option of LHC over practically the full
parameter space of MSSM.Comment: 16 pages, Latex, 4 figures (available on request
Supersymmetric lepton flavour violation in a linear collider: the role of charginos
The occurrence of a significant amount of supersymmetric lepton flavour
violation at laboratory energies, through
mixing, has become a realistic possibility in the wake of the super-Kamiokande
atmospheric neutrino result. This effect can be observed in an e+e- linear
collider with the distinct final state tau+mu+ jets+E_T. We show that the pair
production of charginos can make an important contribution to this process and
has to be taken into account in addition to that of sneutrinos or charged
sleptons. Some case studies are presented with CM energies of 500 and 800 GeV
and integrated luminosities of 50, 500 and 1000 fb-1.Comment: 15 pages, latex, including 2 figure
Probing a Mixed Neutralino Dark Matter Model at the 7 TeV LHC
We have analyzed the prospect of probing a non-universal gaugino mass model
of mixed bino-higgsino dark matter at the current 7 TeV run of LHC. It provides
cosmologically compatible dark matter relic density over two broad bands of
parameters, corresponding to m_{\gl} < m_{\sq} and m_{\gl} \sim m_{\sq}.
The SUSY spectrum of this model has two distinctive features : (i) an
approximate degeneracy among the lighter chargino and neutralino masses, and
(ii) an inverted mass hierarchy of squark masses. We find that these features
can be exploited to obtain a viable signal upto m_{\gl} \sim 800 GeV over
both the parameter bands with an integrated luminosity 5/fb.Comment: Latex, 15 pages, one figur
Reconstructing the Chargino System at Linear Colliders
In most supersymmetric theories charginos, , belong
to the class of the lightest supersymmetric particles. The chargino system can
be reconstructed completely in collider experiments:
. By measuring the total
cross sections and the asymmetries with polarized beams, the chargino masses
and the gaugino-higgsino mixing angles of these states can be determined
accurately. If only the lightest charginos are
kinematically accessible in a first phase of the machine, transverse beam
polarization or the measurement of chargino polarization in the final state is
needed to determine the mixing angles. From these observables the fundamental
SUSY parameters can be derived: the SU(2) gaugino mass , the modulus and
the cosine of the CP-violating phase of the higgsino mass parameter , and
, the ratio of the vacuum expectation values of the two
neutral Higgs doublet fields. The remaining two-fold ambiguity of the phase can
be resolved by measuring the normal polarization of the charginos. Sum rules of
the cross sections can be exploited to investigate the closure of the
two-chargino system.Comment: 25 pages, 6 figure
Like Sign Dilepton Signature for R-Parity Violating SUSY Search at the Tevatron Collider
The like sign dileptons provide the most promising signature for
superparticle search in a large category of -parity violating SUSY models.
We estimate the like sign dilepton signals at the Tevatron collider, predicted
by these models, over a wide region of the MSSM parameter space. One expects an
unambiguous signal upto a gluino mass of GeV ( GeV) with
the present (proposed) accumulated luminosity of .Comment: 12 page LaTeX file; 5 figures available upon request from the autho
Probing Supersymmetry using Event Shape variables at 8 TeV LHC
We have revisited the prospects of Supersymmetry(SUSY) searches at the LHC
with 7 TeV energy along with the prediction of the discovery potential at 8 TeV
energy assuming an integrated luminosity 5 and 20 \invfb with
mSUGRA/CMSSM as a model framework. We discuss further optimization of our
selection strategy which is based on the hadronic event shape variables.
Evaluating the standard model backgrounds and signal rates in detail we predict
the discovery reach in the plane for 7 TeV with 5\invfb
luminosity. We also present the discovery reach for 8 TeV energy with an
integrated luminosity 5\invfb and 20 \invfb. A comparison is made between
our results and the exclusion plots obtained by CMS and ATLAS. Finally,
discovery reach in the gluino and squark mass plane at the 7 TeV and 8 TeV
energy is also presented.Comment: 17 pages, 6 eps figures, 20/fb results and figures added, some
references added, version accepted and to be published in Physical Review
Higgs and SUSY Searches at LHC
I start with a brief introduction to Higgs mechanism and supersymmetry. Then
I discuss the theoretical expectations, current limits and search strategies
for Higgs boson(s) at LHC --- first in the SM and then in the MSSM. Finally I
discuss the signatures and search strategies for the superparticles.Comment: Typos and figure styles corrected; LaTeX (28 pages) including 13 ps
files containing 11 figures; Invited talk at the 5th Workshop on High Energy
Physics Phenomenology (WHEPP-5), Pune, India, 12 - 25 January 199
Looking for the Charged Higgs Boson
This review article starts with a brief introduction to the charged Higgs
boson (H^\pm) in the Minimal Supersymmetric Standard Model (MSSM). It then
discusses the prospects of a relatively light H^\pm boson search via top quark
decay at Tevatron/LHC, and finally a heavy H^\pm boson search at LHC. The
viable channels for H^\pm search are identified in both the cases, with
particular emphasis on the H^\pm --> tau + nu decay channel. The effects of NLO
QCD correction in the SM as well as the MSSM are discussed briefly.Comment: 17 pages with 8 eps figures, Invited review, Reference adde
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