Exotic colored scalars at the LHC

In scenarios that stabilize the electroweak scale, the top quark is typically accompanied by partner particles. In this work, we demonstrate how extended stabilizing symmetries can yield scalar or fermionic top partners that transform as ordinary color triplets but carry exotic electric charges. We refer to these scenarios as "hypertwisted" since they involve modifications to hypercharge in the top sector. As proofs of principle, we construct two hypertwisted scenarios: a supersymmetric construction with spin-0 top partners, and a composite Higgs construction with spin-1/2 top partners. In both cases, the top partners are still phenomenologically compatible with the mass range motivated by weak-scale naturalness. The phenomenology of hypertwisted scenarios is diverse, since the lifetimes and decay modes of the top partners are model dependent. The novel coupling structure opens up search channels that do not typically arise in top-partner scenarios, such as pair production of top-plus-jet resonances. Furthermore, hypertwisted top partners are typically sufficiently long lived to form "top-partnerium" bound states that decay predominantly via annihilation, motivating searches for rare narrow resonances with diboson decay modes.

Section: A Top Partneriummentioning

confidence: 99%

“…Importantly, the studies in Refs. [90][91][92][93] assumed the particle couplings to the Higgs to be negligible relative to their couplings to gluons. For top partners, though, this assumption is not satisfied since y t ∼ g s .…”

Section: A Top Partneriummentioning

confidence: 99%

Colorful Twisted Top Partners and Partnerium at the LHC

Kats

McCullough

Pérez

et al. 2017

“…In fact spin zero composite states made by TC-scalars are expected to be observed. It would therefore be interesting to explore the discovery potential at future colliders of spin zero composite states made by two TC-scalars, 8 some of which will have lepto-quarks quantum numbers [45]. Finally, flavour dynamics and modeling is highly interesting and of immediate impact for the investigation of flavour observables and anomalies.…”

Section: Discussionmentioning

confidence: 99%

Real and complex fundamental partial compositeness

Agugliaro

Sannino

2020

We complete the analysis of the effective field theory at the electroweak scale for minimal models of fundamental partial compositeness. Specifically, we consider fermions in the complex and real representation of the gauge group underlying the composite Higgs dynamics, since the pseudo real representation was investigated earlier. The minimal models feature the cosets SU(4)×SU(4)/SU(4) D and SU(5)/SO(5) respectively for the complex and real representations. We determine the vacuum alignment, the electroweak precision constraints as well as additional collider constraints. We finally discuss the main differences among the different models of minimal partial compositeness.

“…[4]. In addition, the authors of [32] obtained bounds for colored scalars with charges −7/3, 8/3, −10/3 and of different SU (2) weak representations. However, these analyses attributed the dominant partnerium production, binding and decay mechanisms to QCD.…”

Section: Bound State Signal At the Lhcmentioning

confidence: 99%

Bounds and prospects for stable multiply charged particles at the LHC

Jäger

Kvedaraitė

Pérez

et al. 2019

Colored and colorless particles that are stable on collider scales and carry exotic electric charges, so-called multiply-charged heavy stable particles (MCHSPs), exist in extensions of the Standard Model, and can include the top partner(s) in solutions of the hierarchy problem. To obtain bounds on color-triplets and color-singlets of charges up to |Q| = 8, we recast searches for signatures of two production channels: the "open" channel -where the particles are pair-produced above threshold, and are detectable in dedicated LHC searches for stable multiply charged leptons, and the "closed" channel -where a particle-antiparticle pair is produced as a bound state, detectable in searches for a diphoton resonance. We recast the open lepton searches by incorporating the relevant strong-interaction effects for color-triplets. In both open and closed production, we provide a careful assessment of photon-induced processes using the accurate LUXqed PDF, resulting in substantially weaker bounds than previously claimed in the literature for the colorless case. Our bounds for colored MCHSPs are shown for the first time, as the LHC experiments have not searched for them directly. Generally, we obtain nearly charge-independent lower mass limits of around 970 GeV (color-triplet scalar), 1200 GeV (color-triplet fermion), and 880 − 900 GeV (color-singlet fermion) from open production, and strongly chargedependent limits from closed production. In all cases there is a cross-over between dominance by open and closed searches at some charge. We provide prospective bounds for √ s = 13 TeV LHC searches at integrated luminosities of 39.5 fb −1 , 100 fb −1 , and 300 fb −1 . Moreover, we show that a joint observation in the open and the closed channels allows to determine the mass, spin, color, and electric charge of the particle.