Higgs Boson Discovery
Abstract
A search for the Standard Model Higgs boson in proton-proton collisions with the ATLAS detector at the LHC is presented. The datasets used correspond to integrated luminosities of approximately 4.8 $fb^{-1}$ collected at $\sqrt{s}=7$ TeV in 2011 and 5.8 $fb^{-1}$ at $\sqrt{s}=8$ TeV in 2012. Individual searches in the channels $h\to \ell\ell\ell\ell$, $h\to\gamma\gamma$ and $h\to WW\to e\nu\mu\nu$ in the 8 TeV data are combined with previously published results of searches for $H{\rightarrow\,}ZZ^{(*)}$, $WW^{(*)}$, $b\bar{b}$ and $\tau^+\tau^-$ in the 7,TeV data and results from improved analyses of the $h\to \ell\ell\ell\ell$ and $h\to\gamma\gamma$ channels in the 7 TeV data. Clear evidence for the production of a neutral boson with a measured mass of $26.0 \pm 0.4(stat) \pm 0.4(sys)$ GeV is presented. This observation, which has a significance of 5.9 standard deviations, corresponding to a background fluctuation probability of $1.7\times 10^{-9}$, is compatible with the production and decay of the Standard Model Higgs boson
Type
Publication
Phys. Lett.
This landmark paper reports the observation of a new particle consistent with the Standard Model Higgs boson in proton–proton collisions recorded by the ATLAS detector at the LHC.
Key points
- Datasets correspond to integrated luminosities of approximately 4.8 fb⁻¹ at √s = 7 TeV (2011) and 5.8 fb⁻¹ at √s = 8 TeV (2012).
- Results from individual searches in the channels \(H \to ZZ^{(*)} \to \ell\ell\ell\ell\), \(H \to \gamma\gamma\), and \(H \to WW^{(*)} \to e\nu\mu\nu\) (8 TeV data) are combined with previously published 7 TeV results (including \(H \to ZZ^{(*)}\), \(WW^{(*)}\), \(b\bar{b}\), and \(\tau^+\tau^-\)) and improved analyses of the \(H \to ZZ^{(*)} \to \ell\ell\ell\ell\) and \(H \to \gamma\gamma\) channels.
- Clear evidence is presented for the production of a neutral boson with a measured mass of \(126.0 \pm 0.4\,\text{(stat)} \pm 0.4\,\text{(sys)}\) GeV.
- The observation has a significance of 5.9 standard deviations (background fluctuation probability of \(1.7 \times 10^{-9}\)) and is compatible with the production and decay of the Standard Model Higgs boson.
Published in Physics Letters B in 2012; this is one of the two papers (together with the corresponding CMS result) that announced the discovery of the Higgs boson.