Lepton number violation at colliders from kinematically inaccessible gauge bosons

Ruiz, Richard

Abstract

We reevaluate the necessity of WRWR gauge bosons being kinematically accessible to test the left–right symmetric model (LRSM) at hadron colliders. In the limit that WRWR are too heavy, resonant production of sub-TeV Majorana neutrinos N can still proceed at the Large Hadron Collider (LHC) via the process pp→W±∗R→Nℓ±→ℓ±ℓ±+njpp→WR±∗→Nℓ±→ℓ±ℓ±+nj if mediated by a far off-shell WRWR . Traditional searches strategies are insensitive to this regime as they rely on momenta of final states scaling with TeV-scale MWRMWR . For such situations, the process is actually kinematically and topologically identical to the direct production (DP) process pp→W±∗SM→Nℓ±→ℓ±ℓ±+njpp→WSM±∗→Nℓ±→ℓ±ℓ±+nj . In this context, we reinterpret s√=8s=8 TeV LHC constraints on DP rates for the minimal LRSM. For mN=mN= 200–500 GeV and right–left coupling ratio κR=gR/gLκR=gR/gL , we find (MWR/κR)>(MWR/κR)> 1.1–1.8 TeV at 95% CLs. Expected sensitivities to DP at 14 (100) TeV are also recast: with L=1 (10)L=1 (10) ab −1−1 , one can probe (MWR/κR)<(MWR/κR)< 7.9–8.9 (14–40) TeV for mN=mN= 100–700 (1200) GeV, well beyond the anticipated sensitivity of resonant WRWR searches. Findings in terms of gauge invariant dimension-six operators with heavy N are also reported.

Citation

Ruiz, R. (2017). Lepton number violation at colliders from kinematically inaccessible gauge bosons. The European Physical Journal C, 77(6), Article 375. https://doi.org/10.1140/epjc/s10052-017-4950-2

• Journal Article Type: Article
• Acceptance Date: May 28, 2017
• Online Publication Date: Jun 6, 2017
• Publication Date: Jun 6, 2017
• Deposit Date: Jul 5, 2017
• Publicly Available Date: Jul 5, 2017
• Journal: European Physical Journal C: Particles and Fields
• Print ISSN: 1434-6044
• Electronic ISSN: 1434-6052
• Publisher: SpringerOpen
• Peer Reviewed: Peer Reviewed
• Volume: 77
• Issue: 6
• Article Number: 375
• DOI: https://doi.org/10.1140/epjc/s10052-017-4950-2
• Public URL: https://durham-repository.worktribe.com/output/1375438