arXiv subjects

Sreerup Raychaudhuri

Publications and source records attributed to Sreerup Raychaudhuri.

61 records · Page 4Linked to original sources

arXiv1996

SUSY Contributions to R_b and Top Quark Decay

Stop contributions to radiative corrections to R_b and the top quark decay are analysed over the relevant MSSM parameter space. One sees a 30 % increase in the former along with a similar drop in the latter in going from the higgsino dominated to the mixed region. Consequently one can get a viable SUSY contribution to R_b within the constraint of the top quark data only in the mixed region, corresponding to a photino dominated LSP. We discuss the phenomenological implications of this model for top quark decay and direct stop production, which can be tested with the Tevatron data.

hep-ph↗

arXiv1996

Higgs-mediated Slepton Pair-production at the Large Hadron Collider

At the LHC, directly pair-produced sleptons may be easier to identify than those arising in cascade decays of squarks or gluinos. Higgs exchange processes leading to such slepton pair-production are calculated to one-loop in the MSSM. It turns out, surprisingly, that their total contribution can dominate the usual Drell-Yan production in certain regions of the parameter space. In particular, an interesting region with low $\tan β$ is covered by the dominant exchange of the heavier neutral scalar $H^0$.

hep-ph↗

arXiv1995

Singlet-Higgs-Boson Signals at Hadron Colliders

Many extensions of the Standard Model include $SU(2)_L \times U(1)_Y$ singlet higgs bosons, $h^0$, and also vectorlike fermions which couple to it. The production and detection possibilities of such singlet neutral scalars at hadron colliders are considered for different scenarios of vectorlike fermions. We find that for some values of masses and couplings, detection at the CERN Large Hadron Collider (LHC) appears to be a distinct possibility, while at the Fermilab Tevatron upgrade the $h^0$ might be observed only in very favourable circumstances.

hep-ph↗

arXiv1995

Sharpening up the Charged Higgs Boson Signature using Tau Polarization at LHC

The opposite states of the $τ$ polarization resulting from the charged Higgs boson and the $W$ boson decays can be exploited to enhance the $H^\pm$ signal in the inclusive 1-prong hadronic decay channel of $τ$. We suggest practical methods of sharpening up the $H^\pm$ signature in the top quark decay at LHC using this idea. As a result one can carry on the charged Higgs boson search to within $\sim 20 GeV$ of the parent top quark mass over the full parameter space of the MSSM.

hep-ph↗

arXiv1995

Charged Higgs Boson Search at the Tevatron Upgrade Using Tau Polarization

We explore the prospect of charged Higgs boson search in top quark decay at the Tevatron collider upgrade, taking advantage of the opposite states of $τ$ polarization resulting from the $H^\pm$ and $W^\pm$ decays. Methods of distinguishing the two contributions in the inclusive 1-prong hadronic decay channel of $τ$ are suggested. The resulting signature and discovery limit of $H^\pm$ are presented for the Tevatron upgrade as well as the Tevatron$^\star$ and the Ditevatron options.

hep-ph↗

arXiv1994

Observing Virtual LSPs at LEP II

In the minimal supersymmetric extension of the Standard Model (MSSM) with $R$-parity conservation the possibility that the sneutrino and the second lightest neutralino decay dominantly into invisible channels and, in addition to the lightest neutralino, carry missing energy, is still open --- both theoretically and experimentally. It is shown that for a large region of the parameter space allowed by {\rm LEP-I} data, these particles can contribute significantly to the process $e^+ e^- \longrightarrow γ$ + {\rm nothing}. This signal, if it exists, can be easily detected at {\rm LEP-II} as an enhancement over the Standard Model or the conventional MSSM predictions.

hep-ph↗

arXiv1994

Taming the Scalar Mass Problem with a Singlet Higgs Boson

We investigate the fine-tuning problem in the Standard Model and show that Higgs boson and top quark masses consistent with current experimental bounds cannot be obtained unless one extends the particle spectrum. A minimal extension which achieves this involves addition of a singlet real scalar and one generation of vectorlike fermions. We show that this leads to a phenomenologically viable prediction for the mass of the Standard Model Higgs boson.

hep-ph↗