Revealing compressed stops using high-momentum recoils

The electroweak sector of the Minimal Supersymmetric Standard Model (MSSM) -neutralinos, charginos and sleptons -remains relatively weakly constrained at the LHC due in part to the small production cross sections of these particles. In this paper, we study the prospects of searching for decays of heavy Higgs bosons into these superpartners at the high luminosity LHC. In addition to the kinematic handles offered by the presence of a resonant particle in the production chain, heavy Higgs decays can be the dominant production mode of these superpartners, making it possible to extend coverage to otherwise inaccessible regions of the supersymmetry and heavy Higgs parameter space. We illustrate our ideas with detailed collider analyses of two specific topologies: We propose search strategies for heavy Higgs decay to a pair of neutralinos, which can probe heavy Higgs bosons up to 1 TeV in the intermediate tan β(∼ 2 − 8) region, where standard heavy Higgs searches have no reach. Similarly, we show that targeted searches for heavy Higgs decays into staus can probe stau masses up to several hundred GeV. We also provide a general overview of additional decay channels that might be accessible at the high luminosity LHC. This motivates a broader program for LHC heavy Higgs searches.2 Note that there is also a recent ATLAS leptons plus / ET excess that can be related to new exotic decays of the heavy Higgs bosons [33][34][35].

Section: At This Point It Is Illuminating To Observe the Parallels Bmentioning

confidence: 99%

Heavy Higgs as a portal to the supersymmetric electroweak sector

Gori

Liu

Shakya

2019

“…There is also no fine-tuning required to get the correct electroweak scale and Higgs. Thus, in general, it is still interesting to develop experimental search techniques [26][27][28][29][30] to probe stop masses in the 200-800 GeV range that would allow a natural SUSY theory.…”

Section: Jhep05(2016)151 4 Conclusionmentioning

confidence: 99%

A light stop with a heavy gluino: enlarging the stop gap

Cleary

Terning

2016

It is widely thought that increasing bounds on the gluino mass, which feeds down to the stop mass through renormalization group running, are making a light stop increasingly unlikely. Here we present a counter-example. We examine the case of the Minimal Composite Supersymmetric Standard Model which has a light composite stop. The large anomalous dimension of the stop from strong dynamics pushes the stop mass toward a quasi-fixed point in the infrared, which is smaller than standard estimates by a factor of a large logarithm. The gluino can be about three times heavier than the stop, which is comparable to hierarchy achieved with supersoft Dirac gluino masses. Thus, in this class of models, a heavy gluino is not necessarily indicative of a heavy stop.

“…But in the compressed regions, for example mt 1 ≈ mχ0 1 + m t , the decay products of the stop are very soft. In this region, the stop is searched for by using the monojet signature [26][27][28][29][30][31][32]. Based on recent Run-2 (∼ 15 fb −1 ) dataset, the stop mass has been excluded up to ∼ 1 TeV in simplified models [33][34][35][36][37][38][39][40].…”

Section: Introductionmentioning

confidence: 99%

Leptonic mono-top from single stop production at the LHC

Duan¹,

Hikasa²,

Wu³

et al. 2017

Top squark (stop) can be produced via QCD interaction but also the electroweak interaction at the LHC. In this paper, we investigate the observability of the associated production of stop and chargino, pp →t 1χ − 1 , in compressed electroweakino scenarios at 14 TeV LHC. Due to small mass splitting between the lightest neutralino (χ 0 1 ) and chargino (χ − 1 ), the single stop production can give the mono-top signature through the stop decayt 1 → tχ 0 1 . We analyze the leptonic mono-top channel of the single stop production and propose a lab-frame observable cos θ b to reduce the SM backgrounds. We find that such leptonic mono-top events from the single stop production can be probed at 2σ level at the HL-LHC if mt 1 < 760 GeV and mχ0 1 < 150 GeV. Given a discovery of the stop and a measurement of the single stop production cross section, the stop mixing angle can also be determined from the single stop production at the HL-LHC.