This study investigates the prospect of discovering strongly interacting gluinos in different multi-lepton channels with lepton multiplicities greater than or equal to 2 at LHC RUN-III, considering several pMSSM scenarios. The effectiveness of the multivariate analysis (MVA) method with the boosted decision tree (BDT) algorithm is explored to obtain a better significance for different models. Promising results are obtained for the 3-lepton channels, indicating that the use of MVA methods can improve the sensitivity of the search for gluinos at LHC RUN-III. The study probes the multi-lepton signatures arising from gluinos via intermediate eweakinos and sleptons at an early stage of the LHC RUN-III. The heavier eweakinos can give rise to three or four lepton signals, in which the squark hierarchy between the L and R types plays a crucial role. The study considers two sets of benchmark points that satisfy all the collider constraints obtained from the LHC RUN-II data. Moreover, these sets of benchmark points are mostly consistent with WMAP/PLANCK data and the muon (g-2) constraint. The corresponding results from the MVA technique demonstrate that, even for an integrated luminosity of 270   $\rm fb^{-1}$  , the 5 σ discovery prospect of   $\rm fb^{-1}$   for   $\rm fb^{-1}$   TeV in the wino type model is promising. The study also presents various other models that may emerge at the early stage of LHC RUN-III. Wino type models in the scenario where left squarks are light and right squarks are heavy exhibit the best prospect of discovering gluinos in multi-lepton channels in the LHC RUN-III experiment. The findings of this study provide crucial insights into the potential discovery of gluinos in multi-lepton channels.

India

Abhi Mukherjee

Saurabh Niyogi

Sujoy Poddar

Jyoti Prasad Saha

Prospects of gluino searches in multi-lepton channels in light of the ongoing LHC RUN-III

As a sequel to our recent paper we examine the phenomenology of the full electroweakino sector of the pMSSM without invoking the ad hoc but often employed assumption that the heavier ones are decoupled. We showcase the importance of the heavier electroweakinos using several generic models with different hierarchies among the slepton and electroweakino masses. We obtain constraints from the LHC  data which are stronger than that for decoupled heavier electroweakinos. Using the additional constraints from the observed dark matter relic density of the universe and the precisely measured anomalous magnetic moment of the muon we determine the allowed parameter space. We then show that novel  signatures with m &gt; 3 may be observed before the next long shut down of the LHC.

Germany

Manimala Chakraborti

Amitava Datta

Nabanita Ganguly

Multilepton signals of heavier electroweakinos at the LHC

Higgsinos and Wino have strong motivations for being Dark Matter (DM) candidates in supersymmetry, but their annihilation cross sections are quite large. For thermal generation and a single component DM setup the higgsinos or wino may have masses of around 1 or 2-3 TeV respectively. For such DM candidates, a small amount of slepton coannihilation may decrease the effective DM annihilation cross section. This, in turn reduces the lower limit of the relic density satisfied DM mass by more than 50%. Almost a similar degree of reduction of the same limit is also seen for squark coannihilations. However, on the contrary, for near degeneracy of squarks and higgsino DM, near its generic upper limit, the associated coannihilations may decrease the relic density, thus extending the upper limit towards higher DM masses. We also compute the direct and indirect detection signals. Here, because of the quasi-mass degeneracy of the squarks and the LSP, we come across a situation where squark exchange diagrams may contribute significantly or more strongly than the Higgs exchange contributions in the spin-independent direct detection cross section of DM. For the higgsino-DM scenario, we observe that a DM mass of 600 GeV to be consistent with WMAP/PLANCK and LUX data for sfermion coannihilations. The LUX data itself excludes the region of 450 to 600 GeV, by a half order of magnitude of the cross-section, well below the associated uncertainty. The similar combined lower limit for a wino DM is about 1.1 TeV. There is hardly any collider bound from the LHC for squarks and sleptons in such a compressed scenario where sfermion masses are close to the mass of a higgsino/wino LSP.

Utpal Chattopadhyay

How light a higgsino or a wino dark matter can become in a compressed scenario of MSSM

We investigate the heavier electroweakino sectors in several versions of the MSSM, which has not been explored so far in the light of the LHC data, and obtain new bounds using the ATLAS Run I constraints in the <math><mn>3</mn><mi>l</mi><mo>+</mo><msub><mrow><mi>E̸</mi></mrow><mrow><mi>T</mi></mrow></msub></math> channel. We also venture beyond the trilepton events and predict several novel <math><mtext>multilepton</mtext><mo>+</mo><msub><mrow><mi>E̸</mi></mrow><mrow><mi>T</mi></mrow></msub></math> signatures of these electroweakinos which may show up during LHC Run II before the next long shutdown. These signals can potentially distinguish between various models with nondecoupled heavier electroweakinos and the much studied ones with decoupled heavier electroweakinos.

New limits on heavier electroweakinos and their LHC signatures

Arghya Choudhury

Reduced LHC constraints for higgsino-like heavier electroweakinos

Using the chargino-neutralino and slepton search results from the LHC in conjunction with the WMAP/PLANCK and ( g − 2) μ data, we constrain several generic pMSSM models with decoupled strongly interacting sparticles, heavier Higgs bosons and characterized by different hierarchies among the EW sparticles. We find that some of them are already under pressure and this number increases if bounds from direct detection experiments like LUX are taken into account, keeping in mind the associated uncertainties. The XENON1T experiment is likely to scrutinize the remaining models closely. Analysing models with heavy squarks, a light gluino along with widely different EW sectors, we show that the limits on m g ˜ $$ {m}_{\tilde{g}} $$ are not likely to be below 1.1 TeV, if a multichannel analysis of the LHC data is performed. Using this light gluino scenario we further illustrate that in future LHC experiments the models with different EW sectors can be distinguished from each other by the relative sizes of the n -leptons + m -jets + T signals for different choices of n .