The radiation valley and exotic resonances in Wγ production at the LHC

Abstract

The tree-level partonic angular distribution of Standard Model W γ production possesses a feature known as the Radiation Amplitude Zero (RAZ) where destructive interference causes the cross section to vanish. At the proton level the exact cancellation disappears, however, one can find a dip in the central region of the angular distributions, here called the Radiation Valley (RV). In this paper, we show how the sensitivity for W ( ν)γ resonances can be significantly improved if one focuses on events in the RV region. Using this technique, we find that the LHC could probe a larger range of resonance masses, equivalent to increasing the luminosity by a factor of 2 − 3 over conventional searches. The exact increase depends on the spin of the W γ resonance and exactly how it couples to electroweak gauge bosons.

Review of Neutral Naturalness

“…These and other SM vector decay modes can be used to detect pNGB Higgs models as well, such as SO(7)/SO(6) [63]. The SM exhibits a cancellation in W γ production which can be used to strengthen these searches [98]. While the final decay product is the most conspicuous signal of these quirky states, the pattern of radiation they produce as they de-excite can also lead to signals in the underlying event [99].…”

Zeros of amplitude in the associated production of photon and leptoquark at $$\varvec{e}$$-$$\varvec{p}$$ collider

“…The criteria for these zeros to lie inside the kinematically allowed region of phase space are also well-studied [8][9][10]. Although various contaminations like initial and final state photon radiations, QED and QCD loop contributions, uncertainties in partonic centre of momentum reconstruction, etc., smear the effect of RAZ [11][12][13][14][15][16][17][18][19], noticeable dip in the angular distribution still remains [20][21][22].…”

The quirk trajectory

“…Subsequently, they will annihilate almost promptly into the SM particles after production. Such quirk signals can be searched through resonances in the SM final states [10][11][12][13][14][15]. When ∈ [10 keV, 10 MeV], the quirk pair oscillation amplitude is microscopic ( µm), while the energy loss due to photon and hidden glueball radiation is not efficient.…”