Searches For New Bosons Coupling To e-q Pairs At HERA And Other Colliders

TL;DR

This paper reviews recent searches for new bosons, such as leptoquarks and squarks, at HERA and other colliders, highlighting their potential to discover physics beyond the Standard Model through various experimental constraints.

Contribution

It provides an updated analysis of HERA data on bosons coupling to lepton-quark pairs, comparing collider sensitivities with indirect constraints and exploring prospects for new physics discovery.

Findings

HERA's sensitivity to leptoquarks and squarks exceeds some indirect bounds.

HERA and Tevatron can explore new regions of mass-coupling parameter space.

Potential signals of lepton flavor violation are discussed.

Abstract

The early observation at HERA of an excess of events compared to the expectation from the Standard Model in very short distance $e^+p$ deep-inelastic scattering processes has renewed the interest in the search for new physics which could manifest in electroweak-like interactions. New preliminary results from the H1 and ZEUS experiments making use of all available $e^+p$ data are reviewed here, with an emphasis on the search for new bosons possessing Yukawa couplings to lepton-quark pairs. The sensitivity of HERA to leptoquarks, and to squarks of R-parity violating supersymmetry, is confronted to existing indirect constraints from rare and forbidden semi-leptonic decays, atomic parity violation and neutrinoless double-beta decay, as well as to direct constraints from LEP and Tevatron colliders. The HERA and Tevatron colliders are found to offer exciting prospects for new physics, accessing yet unexplored domains of the mass-coupling plane. Possible striking manifestation of explicit lepton flavour violation is also discussed.