Physics potential for the measurement of $${\sigma (H\nu \bar{\nu })\times \text {BR}(H\rightarrow \mu ^+\mu ^-)}$$ σ ( H ν ν ¯ ) × BR ( H → μ + μ - ) at the 1.4 TeV CLIC collider

Abstract

The future compact linear collider (CLIC) offers a possibility for a rich precision physics programme, in particular in the Higgs sector through the energy staging. This is the first paper addressing the measurement of the standard model Higgs boson decay into two muons at 1.4 TeV CLIC. With respect to similar studies at future linear colliders, this paper includes several novel contributions to the statistical uncertainty of the measurement. The latter includes the equivalent photon approximation employed to describe e + e − and eγ interactions whenever the virtuality of the mediated photon is smaller than 4 GeV and realistic forward electron tagging based on energy deposition maps in the forward calorimeters, as well as several processes with the Beamstrahlung photons that results in irreducible contribution to the signal. In addition, coincidence of the Bhabha scattering with the signal and background processes is considered, altering the signal selection efficiency. The study is performed using a fully simulated CLIC_ILD detector model. It is shown that the branching ratio for the Higgs decay into a pair of muons BR(H → μ + μ − ) times the Higgs production cross-section in W W -fusion σ (H νν) can be measured with 38 % statistical accuracy at √ s = 1.4 TeV, assuming an integrated luminosity of 1.5 ab −1 with unpolarised beams. If 80 % electron beam polarisation is considered, the statistical uncertainty of the measurement is reduced to 25 %. Systematic uncertainties are negligible in comparison to the statistical uncertainty.This work was carried out in the framework of the CLICdp collaboration. a

Higgs physics at the CLIC electron–positron linear collider

“…The efficient rejection of background relies on the excellent detector momentum resolution, which directly influences the width of the reconstructed di-muon invariant mass peak. Signal and background events have been simulated at and using the and detector models respectively [58, 59]. In contrast with other studies presented in this paper, an electron beam polarisation of is assumed owing to the very small branching ratio for the decay.…”

Prospects of measuring the branching fraction of the Higgs boson decaying into muon pairs at the International Linear Collider

“…Since at √ s = 500 GeV the momenta of the muons are higher than in the √ s = 250 GeV case, the transverse momentum resolution is closer to the asymptotic performance of 2 × 10 −5 GeV −1 , and thus the "effective" resolution gets closer to the case of 2 × 10 −5 GeV −1 , Otherwise, the conclusions remain similar to the √ s = 250 GeV case, underlining again the importance to achieve the ILD design goal on the transverse momentum resolution. A similar study has also been performed by the Compact LInear Collider (CLIC) [29], based on e + e − → νν H at √ s = 1.4 TeV (the qqh contribution is negligible at 1.4 TeV). Figure 11 in Ref.…”

“…The prospects for measuring the H → μ + μ − decay at linear e + e − colliders have been studied previously under various conditions [12,[26][27][28][29][30], but all studies except Ref. [30] have been performed at a centre-of-mass energy of 1 TeV or higher.…”

Fat jet signature of a heavy neutrino at a lepton collider

“…Note, that M N upto 1 TeV can also be probed at ILC, in it's 1 TeV run.We stress that the model signature for a very heavy N is quite distinct than that of M N in the 100 GeV mass range, that we explore in detail. See [80,[82][83][84][85][86][87][88][89][90][91][92][93] for discovery prospect of different BSM scenarios at CLIC.…”