Leptons lurking in semi-visible jets at the LHC

Cazzaniga, Cesare; Cosa, A. De

doi:10.1140/epjc/s10052-022-10775-2

Cited by 8 publications

(8 citation statements)

References 71 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The dark pseudo-scalar ( ) and vector ( ) meson masses can differ according to the non-perturbative dynamics of the hidden sector, even for mass-degenerate dark quarks. Following a similar approach as in [ 16 ], we employed the lattice QCD fits in [ 32 ] to predict the masses of dark vector mesons from the input ratio , where (HiddenValley:Lambda) is the dark confinement scale, which fixes the overall mass scale for the dark bound states. As a benchmark, has been set to 10 GeV and the ratio , therefore fixing (4900111:m0, 4900211:m0) at 8 GeV and (4900113:m0, 4900213:m0) at GeV.…”

Section: Monte Carlo Simulationsmentioning

confidence: 99%

“…Following the same approach as in [ 16 ], we have considered the same background processes as in the CMS semi-visible jets search [ 17 ]. All the background samples have been generated at LO with the MadGraph5_aMC@NLO event generator using the NN23LO1 parton distribution functions from the Lhapdf repository.…”

Section: Monte Carlo Simulationsmentioning

confidence: 99%

“…[ 6 – 12 ]). Assuming that the dark sector is strongly coupled, and that the confinement scale of the theory is sufficiently small, the mixture of stable and unstable dark bound states coming from the hadronization of dark quarks generates semi-visible jets at collider experiments [ 10 – 16 ]. These appear as visible jets of particles in the detectors, with missing transverse momentum ( ) aligned with the direction of one of the jets.…”

Section: Introductionmentioning

confidence: 99%

“…Fully hadronic semi-visible jets signatures have been proposed in [ 11 , 13 – 15 ] and searched for by the CMS and ATLAS experiments in s- and t-channel production modes [ 17 , 18 ]. Signatures with semi-visible jets enriched in leptons from dark photon decays have been recently proposed in [ 16 ]. In this Letter we present a simplified model developed following [ 19 ], in which a mediator acts as a messenger between the visible and dark sectors, coupling to SM quarks and leptons, enabling the decay of dark bound states to lepton pairs and leading to a -enriched semi-visible jets (SVJ ) signature.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Uncovering tau leptons-enriched semi-visible jets at the LHC

Beauchesne,

Cazzaniga,

de Cosa

et al. 2023

Eur. Phys. J. C

Self Cite

View full text Add to dashboard Cite

This Letter proposes a new signature for confining dark sectors at the Large Hadron Collider. Under the assumption of a QCD-like hidden sector, hadronic jets containing stable dark bound states could manifest in proton-proton collisions. We present a simplified model with a $$Z'$$ Z ′ boson yielding the production of jets made up of dark bound states and subsequently leading to the decays of those that are unstable to $$\tau $$ τ leptons and Standard Model quarks. The resulting signature is characterised by non-isolated $$\tau $$ τ lepton pairs inside semi-visible jets. We estimate the constraints on our model from existing CMS and ATLAS analyses. We propose a set of variables that leverage the leptonic content of the jet and exploit them in a supervised jet tagger to enhance the signal-to-background separation. Furthermore, we discuss the performance and limitations of current triggers for accessing sub-TeV $$Z'$$ Z ′ masses, as well as possible strategies that can be adopted by experiments to access such low mass regions. We estimate that with the currently available triggers, a high mass search can claim a $$5 \sigma $$ 5 σ discovery (exclusion) of the $$Z'$$ Z ′ boson with a mass up to 4.5 TeV (5.5 TeV) with the full Run 2 data of the LHC when the fraction of unstable dark hadrons decaying to $$\tau $$ τ lepton pairs is around $$50\%$$ 50 % , and with a coupling of the $$Z'$$ Z ′ to right-handed up-type quarks of 0.25. Furthermore, we show that, with new trigger strategies for Run 3, it may be possible to access $$Z'$$ Z ′ masses down to 700 GeV, for which the event topology is still composed of two resolved semi-visible jets.

show abstract

Section: Monte Carlo Simulationsmentioning

confidence: 99%

Section: Monte Carlo Simulationsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Uncovering tau leptons-enriched semi-visible jets at the LHC

Beauchesne,

Cazzaniga,

de Cosa

et al. 2023

Eur. Phys. J. C

Self Cite

View full text Add to dashboard Cite

show abstract

“…Following the pioneering papers on Hidden Valleys [2][3][4], a number of other classes of signatures have been identified, e.g. lepton jets [5][6][7][8][9][10][11], emerging jets [12][13][14], semivisible jets [15][16][17][18][19][20], and soft bombs [21,22]. The properties of the dark sector can be parameterized by combination of physically meaningful choices: a confinement scale Λ D , the number of dark colors n C , and the num-ber of dark quark flavors n F .…”

Section: Introductionmentioning

confidence: 99%

Dark Sector Showers in the Lund Jet Plane

Cohen¹,

Roloff²,

Scherb³

2023

Preprint

View full text Add to dashboard Cite

We investigate the consequences of models where dark sector quarks could be produced at the LHC, which subsequently undergo a dark parton shower, generating jets of dark hadrons that ultimately decay back to Standard Model hadrons. This yields collider objects that can be nearly indistinguishable from Standard Model jets, motivating the reliance on substructure observables to tease out the signal. However, substructure predictions are sensitive to the details of the incalculable dark hadronization. We show that the Lund jet plane provides a very effective tool for designing observables that are resilient against the unknown impact of dark hadronization on the substructure properties of dark sector jets.

show abstract

Dark showers from Z-dark Z′ mixing

Cheng,

Jiang,

et al. 2024

J. High Energ. Phys.

View full text Add to dashboard Cite

We discuss dark shower signals at the LHC from a dark QCD sector, containing GeV-scale dark pions. The portal with the Standard Model is given by the mixing of the Z boson with a dark Z′ coupled to the dark quarks. Both mass and kinetic mixings are included, but the mass mixing is the essential ingredient, as it is the one mediating visible decays of the long-lived dark pions. We focus especially on the possibility that the dark Z′ is lighter than the Z. Indirect constraints are dominated by electroweak precision tests, which we thoroughly discuss, showing that both Z-pole and low-energy observables are important. We then recast CMS and LHCb searches for displaced dimuon resonances to dark shower signals initiated by the production of on-shell Z or Z′, where the visible signature is left by a dark pion decaying to μ+μ−. We demonstrate how dark shower topologies have already tested new parameter space in Run 2, reaching better sensitivity on a light dark Z′ compared to the flavor-changing decays of B mesons, which can produce a single dark pion at a time, and the electroweak precision tests.

show abstract

Leptons lurking in semi-visible jets at the LHC

Cited by 8 publications

References 71 publications

Uncovering tau leptons-enriched semi-visible jets at the LHC

Uncovering tau leptons-enriched semi-visible jets at the LHC

Dark Sector Showers in the Lund Jet Plane

Dark showers from Z-dark Z′ mixing

Contact Info

Product

Resources

About