DOI: 10.17182/hepdata.80812.v2/t2
title: "Table 2" of "A search for high-mass resonances decaying to $\tau\nu$ in $pp$ collisions at $\sqrt{s}$ = 13 TeV with the ATLAS detector"

description: Number of expected Standard Model background events including total statistical and systematic uncertainty added in quadrature (calculated before applying the statistical fitting procedure), number of observed events, and the observed and expected 95% CL upper limits on the visible $\tau\nu$ production cross section, $\sigma_{\rm vis} = \sigma(pp \to \tau\nu +X) \cdot \mathcal{A} \cdot \varepsilon$, for $m_{\rm T}$ thresholds ranging from 250 to 1800 GeV. See HepData abstract for details on how to use this data for reinterpretation.
description: CERN-LHC. A search for high-mass resonances decaying to $\tau\nu$ in $pp$ collisions at $\sqrt{s}$ = 13 TeV with the ATLAS detector.

 Units of GeV and pb are used for all data in this entry, which may be different to those used in the publication. 

 Fiducial region: 
 - No electrons or muons 
 - $p_{\rm T}$(e) &gt; 20 GeV, |$\eta$(e)| &lt; 2.47
 - $p_{\rm T}$($\mu$) &gt; 20 GeV, |$\eta$($\mu$)| &lt; 2.5
 - At least one hadronic tau decay ($\tau_{\rm had-vis}$)
 - $p_{\rm T}$($\tau_{\rm had-vis}$) &gt; 50 GeV, |$\eta$($\tau_{\rm had-vis}$)| &lt; 2.4
 - Choose $\tau_{\rm had-vis}$ with highest $p_{\rm T}$
 - $E_{\rm T}^{\rm miss}$ &gt; 150 GeV
 - 0.7 &lt; $p_{\rm T}$($\tau_{\rm had-vis}$) / $E_{\rm T}^{\rm miss}$ &lt; 1.3 
 - $\Delta\phi$($\tau_{\rm had-vis}$, $E_{\rm T}^{\rm miss}$) &gt; 2.4 rad 
 - $m_{\rm T}$($\tau_{\rm had-vis}$, $E_{\rm T}^{\rm miss}$) &gt; threshold 
 - Choose threshold in range 250-1800 GeV in 50 GeV steps

 Note: significant activity near the chosen $\tau_{\rm had-vis}$ would reduce its identification efficiency. If signals with a busy final state are considered we suggest to reject events if the scalar sum $p_{\rm T}$ of stable charged particles within $\Delta R$ = 0.4 or neutral particles within $\Delta R$ = 0.2 of the chosen $\tau_{\rm had-vis}$ is larger than a few GeV (not including pileup or decay products of the chosen $\tau_{\rm had-vis}$)
 
 These results can be reinterpreted for alternate signal models using the limits on the visible $\tau\nu$ production cross section ($\sigma_{\rm vis} = \sigma \times \mathcal{A} \times \varepsilon$) provided in Table 2. 

 Reinterpretation requires calculation of: 
 - $\sigma$: signal cross section including production and decay
 - $\mathcal{A}$: acceptance of fiducial selection at generator level
 - $\varepsilon$: reconstruction efficiency

 First, calculate the visible cross section for each $m_{\rm T}$ threshold at a single parameter-space point of the signal model is question. The parameter-space point is excluded if the visible cross section is larger than the limit at any $m_{\rm T}$ threshold. Repeat the process for all parameter-space points and models to determine the excluded regions. 

 The reconstruction efficiency is dependent on $m_{\rm T}$, and therefore on the $m_{\rm T}$ distribution of the signal model. It can be incorporated by weighting generated events by the parameterized efficiency: 
 $\varepsilon$($m_{\rm T}$ [TeV]) = 0.633 - 0.313$m_{\rm T}$ + 0.0688$m_{\rm T}^2$ - 0.00575$m_{\rm T}^3$

 For reference, the optimal $m_{\rm T}$ thresholds for the SSM and NU models are given in Table 5, the acceptance and acceptance times efficiency for the SSM model can be found in Tables 6 and 7 and the model independent reconstruction efficiency can be found in Table 8.