Pseudorapidity distributions of charged particles as a function of mid- and forward rapidity multiplicities in pp collisions at $\sqrt{s}$ = 5.02, 7 and 13 TeV

The ALICE collaboration Acharya, Shreyasi ; Adamova, Dagmar ; Adler, Alexander ; et al.
Eur.Phys.J.C 81 (2021) 630, 2021.
Inspire Record 1818157 DOI 10.17182/hepdata.106205

The multiplicity dependence of the pseudorapidity density of charged particles in proton-proton (pp) collisions at centre-of-mass energies $\sqrt{s}$ = 5.02, 7 and 13 TeV measured by ALICE is reported. The analysis relies on track segments measured in the midrapidity range ($|\eta| < 1.5$). Results are presented for inelastic events having at least one charged particle produced in the pseudorapidity interval $|\eta|<1$ ($\mathrm{INEL}_{>0}$). The multiplicity dependence of the pseudorapidy density of charged particles is measured with mid and forward rapidity multiplicity estimators, the latter being less affected by autocorrelations. A detailed comparison with predictions from the PYTHIA 8 and EPOS LHC event generators is also presented. Both generators provide a good description of the data.

6 data tables

Charged-particle pseudorapidity density for forward multiplicity classes as a function of $\eta$ in pp collisions at $\sqrt{s} = 5.02\,\mathrm{TeV}$. Statistical errors are generally insignificant.

Charged-particle pseudorapidity density for forward multiplicity classes as a function of $\eta$ in pp collisions at $\sqrt{s} = 7\,\mathrm{TeV}$. Statistical errors are generally insignificant.

Charged-particle pseudorapidity density for forward multiplicity classes as a function of $\eta$ in pp collisions at $\sqrt{s} = 13\,\mathrm{TeV}$. Statistical errors are generally insignificant.

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Measurements of production cross sections of the Higgs boson in the four-lepton final state in proton–proton collisions at $\sqrt{s} = 13\,\text {Te}\text {V} $

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
Eur.Phys.J.C 81 (2021) 488, 2021.
Inspire Record 1850544 DOI 10.17182/hepdata.102525

Production cross sections of the Higgs boson are measured in the H $\to$ ZZ $\to$ $4\ell$ ($\ell$ $=$ e, $\mu$) decay channel. A data sample of proton-proton collisions at a center-of-mass energy of 13 TeV, collected by the CMS detector at the LHC and corresponding to an integrated luminosity of 137 fb$^{-1}$ is used. The signal strength modifier $\mu$, defined as the ratio of the Higgs boson production rate in the $4\ell$ channel to the standard model (SM) expectation, is measured to be $\mu$ $=$ 0.94 $\pm$ 0.07 (stat) ${}^{+0.09}_{-0.08}$ (syst) at a fixed value of $m_H$ = 125.38 GeV. The signal strength modifiers for the individual Higgs boson production modes are also reported. The inclusive fiducial cross section for the H $\to$ $4\ell$ process is measured to be 2.84 $^{+0.23}_{-0.22}$ (stat) ${}^{+0.26}_{-0.21}$ (syst) fb, which is compatible with the SM prediction of 2.84 $\pm$ 0.15 fb for the same fiducial region. Differential cross sections as a function of the transverse momentum and rapidity of the Higgs boson, the number of associated jets, and the transverse momentum of the leading associated jet are measured. A new set of cross section measurements in mutually exclusive categories targeted to identify production mechanisms and kinematical features of the events is presented. The results are in agreement with the SM predictions.

13 data tables

Integrated Fiducial Higgs cross section. The first uncertainty is the combined statistical uncertainty, the second is the combined systematic uncertainty. As described in the publication, the fiducial volume for 7 and 8 TeV is different than for 13 TeV.

Integrated Fiducial Higgs cross section individually with 2016, 2017 and 2018 dataset and with full Run 2 dataset. The first uncertainty is the combined statistical uncertainty, the second is the combined systematic uncertainty. Results are shown inclusively for all final states.

Higgs fiducial cross section in bins of pT for the 4 leptons. The first uncertainty is statistical, the second is systematic uncertainties. The numbers in this HEP data entry are not divided by the bin width, and therefore the units are in fb.

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Version 2
Measurement of the top quark mass using events with a single reconstructed top quark in pp collisions at $\sqrt{s}$ = 13 TeV

The CMS collaboration Tumasyan, Armen ; Adam, Wolfgang ; Andrejkovic, Janik Walter ; et al.
CMS-TOP-19-009, 2021.
Inspire Record 1911567 DOI 10.17182/hepdata.102987

A measurement of the top quark mass is performed using a data sample enriched with single top quark events produced in the $t$ channel. The study is based on proton-proton collision data, corresponding to an integrated luminosity of 35.9 fb$^{-1}$, recorded at $\sqrt{s}$ = 13 TeV by the CMS experiment at the LHC in 2016.Candidate events are selected by requiring an isolated high-momentum lepton (muon or electron) and exactly two jets, of which one is identified as originating from a bottom quark. Multivariate discriminants are designed to separate the signal from the background. Optimized thresholds are placed on the discriminant outputs to obtain an event sample with high signal purity. The top quark mass is found to be 172.13$^{+0.76}_{-0.77}$ GeV, where the uncertainty includes both the statistical and systematic components, reaching sub-GeV precision for the first time in this event topology. The masses of the top quark and antiquark are also determined separately using the lepton charge in the final state, from which the mass ratio and difference are determined to be 0.9952$^{+0.0079}_{-0.0104}$ and 0.83$^{+1.79}_{-1.35}$ GeV, respectively. The results are consistent with $CPT$ invariance.

19 data tables

Top quark mass measured inclusive of lepton flavor and charge. The uncertainties are given in two parts, the first part is the combination of statistical (stat) and profiled (prof) uncertainties and the second part is for the experimental (ext) uncetrinaties.

Top quark mass measured inclusive of lepton flavor and for positively charged lepton.

Top quark mass measured inclusive of lepton flavor and for negatively charged lepton.

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Test of lepton universality in beauty-quark decays

The LHCb collaboration Aaij, Roel ; Abellán Beteta, Carlos ; Ackernley, Thomas ; et al.
LHCb-PAPER-2021-004, 2021.
Inspire Record 1852846 DOI 10.17182/hepdata.106855

The Standard Model of particle physics currently provides our best description of fundamental particles and their interactions. The theory predicts that the different charged leptons, the electron, muon and tau, have identical electroweak interaction strengths. Previous measurements have shown a wide range of particle decays are consistent with this principle of lepton universality. This article presents evidence for the breaking of lepton universality in beauty-quark decays, with a significance of 3.1 standard deviations, based on proton-proton collision data collected with the LHCb detector at CERN's Large Hadron Collider. The measurements are of processes in which a beauty meson transforms into a strange meson with the emission of either an electron and a positron, or a muon and an antimuon. If confirmed by future measurements, this violation of lepton universality would imply physics beyond the Standard Model, such as a new fundamental interaction between quarks and leptons.

1 data table

Likelihood function from the fit to the nonresonant $B^+$ --> $K^+\ell^+ \ell^−$ candidates profiled as a function of $R_K$.


Version 2
Measurements of Higgs boson production and couplings in diboson final states with the ATLAS detector at the LHC

The ATLAS collaboration Aad, Georges ; Abajyan, Tatevik ; Abbott, Brad ; et al.
Phys.Lett.B 726 (2013) 88-119, 2013.
Inspire Record 1241574 DOI 10.17182/hepdata.61748

Measurements are presented of production properties and couplings of the recently discovered Higgs boson using the decays into boson pairs, $H\rightarrow\gamma\gamma$, $H\rightarrow ZZ^{*}\rightarrow 4 \ell$ and $H\rightarrow W W \rightarrow \ell\nu\ell\nu$. The results are based on the complete pp collision data sample recorded by the ATLAS experiment at the CERN Large Hadron Collider at centre-of-mass energies of 7 TeV and 8 TeV, corresponding to an integrated luminosity of about 25 fb$^{-1}$. Evidence for Higgs boson production through vector-boson fusion is reported. Results of combined fits probing Higgs boson couplings to fermions and bosons, as well as anomalous contributions to loop-induced production and decay modes, are presented. All measurements are consistent with expectations for the Standard Model Higgs boson.

3 data tables

-2 log Likelihood in the $(\mu^f_{{\mathrm{{ggF}}+ttH}}, \mu^f_{{\mathrm{{VBF}}+VH}})$ plane for the $f=H\to \gamma\gamma$ channel and a Higgs boson mass $m_H = 125.5$ GeV. The original plain-text and ROOT files from <a href="https://doi.org/10.7484/inspirehep.data.a78c.hk44">10.7484/inspirehep.data.a78c.hk44</a> are accessible by clicking "Resources".

-2 log Likelihood in the $(\mu^f_{{\mathrm{{ggF}}+ttH}}, \mu^f_{{\mathrm{{VBF}}+VH}})$ plane for the $f=H\to ZZ^*\to 4\ell$ channel and a Higgs boson mass $m_H = 125.5$ GeV. The sharp lower edge is due to the small number of events in this channel and the requirement of a positive pdf. The original plain-text and ROOT files from <a href="https://doi.org/10.7484/inspirehep.data.rf5p.6m3k">10.7484/inspirehep.data.rf5p.6m3k</a> are accessible by clicking "Resources".

-2 log Likelihood in the $(\mu^f_{{\mathrm{{ggF}}+ttH}}, \mu^f_{{\mathrm{{VBF}}+VH}})$ plane for the $f=H\to WW^*\to\ell\nu\ell\nu$ channel and a Higgs boson mass $m_H = 125.5$ GeV. The original plain-text and ROOT files from <a href="https://doi.org/10.7484/inspirehep.data.26b4.ty5f">10.7484/inspirehep.data.26b4.ty5f</a> are accessible by clicking "Resources".


Version 2
Comprehensive measurements of $t$-channel single top-quark production cross sections at $\sqrt{s} = 7$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Phys.Rev.D 90 (2014) 112006, 2014.
Inspire Record 1303905 DOI 10.17182/hepdata.64385

This article presents measurements of the $t$-channel single top-quark ($t$) and top-antiquark ($\bar{t}$) total production cross sections $\sigma(tq)$ and $\sigma(\bar{t}q)$, their ratio $R_{t}=\sigma(tq)/\sigma(\bar{t}q)$, and a measurement of the inclusive production cross section $\sigma(tq + \bar{t}q)$ in proton--proton collisions at $\sqrt{s} = 7$ TeV at the LHC. Differential cross sections for the $tq$ and $\bar{t}q$ processes are measured as a function of the transverse momentum and the absolute value of the rapidity of $t$ and $\bar{t}$, respectively. The analyzed data set was recorded with the ATLAS detector and corresponds to an integrated luminosity of 4.59 fb$^{-1}$. Selected events contain one charged lepton, large missing transverse momentum, and two or three jets. The cross sections are measured by performing a binned maximum-likelihood fit to the output distributions of neural networks. The resulting measurements are $\sigma(tq)= 46\pm 6\; \mathrm{pb}$, $\sigma(\bar{t}q)= 23 \pm 4\; \mathrm{pb}$, $R_{t}=2.04\pm 0.18$, and $\sigma(tq + \bar{t}q)= 68 \pm 8\; \mathrm{pb}$, consistent with the Standard Model expectation. The uncertainty on the measured cross sections is dominated by systematic uncertainties, while the uncertainty on $R_{t}$ is mainly statistical. Using the ratio of $\sigma(tq + \bar{t}q)$ to its theoretical prediction, and assuming that the top-quark-related CKM matrix elements obey the relation $|V_{tb}|\gg |V_{ts}|, |V_{td}|$, we determine $|V_{tb}|=1.02 \pm 0.07$.

35 data tables

Differential t-channel top-quark production cross sections and normalized differential t-channel top-quark production cross sections as functions of PT(TOP).

Differential t-channel top-quark production cross sections and normalized differential t-channel top-quark production cross sections as functions of PT(TOPBAR).

Differential t-channel top-quark production cross sections and normalized differential t-channel top-quark production cross sections as functions of ABS(YRAP(T)).

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Angular Analysis of the $B^{+}\rightarrow K^{\ast+}\mu^{+}\mu^{-}$ Decay

The LHCb collaboration Aaij, Roel ; Abellán Beteta, Carlos ; Ackernley, Thomas ; et al.
Phys.Rev.Lett. 126 (2021) 161802, 2021.
Inspire Record 1838196 DOI 10.17182/hepdata.105273

We present an angular analysis of the $B^{+}\rightarrow K^{\ast+}(\rightarrow K_{S}^{0}\pi^{+})\mu^{+}\mu^{-}$ decay using 9$\,\mbox{fb}^{-1}$ of $pp$ collision data collected with the LHCb experiment. For the first time, the full set of CP-averaged angular observables is measured in intervals of the dimuon invariant mass squared. Local deviations from Standard Model predictions are observed, similar to those in previous LHCb analyses of the isospin-partner $B^{0}\rightarrow K^{\ast0}\mu^{+}\mu^{-}$ decay. The global tension is dependent on which effective couplings are considered and on the choice of theory nuisance parameters.

38 data tables

Results for the CP-averaged observables Fl, Afb and S3–S9. The first uncertainties are statistical and the second systematic.

Results for the optimised observables FL and P1–P'8. The first uncertainties are statistical and the second systematic.

The CP-averaged observable Fl versus q2. The first (second) error bars represent the statistical (total) uncertainties.

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Measurement of the $CP$-violating phase $\phi_s$ in $B^0_s \to J/\psi\phi$ decays in ATLAS at 13 TeV

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abbott, Dale Charles ; et al.
Eur.Phys.J.C 81 (2021) 342, 2021.
Inspire Record 1776624 DOI 10.17182/hepdata.103066

A measurement of the $B^0_s \to J/\psi\phi$ decay parameters using 80.5 fb$^{-1}$ of integrated luminosity collected with the ATLAS detector from 13 TeV proton-proton collisions at the LHC is presented. The measured parameters include the $CP$-violating phase $\phi_s$, the width difference $\Delta\Gamma_{s}$ between the $B^0_s$ meson mass eigenstates and the average decay width $\Gamma_{s}$. The values measured for the physical parameters are combined with those from 19.2 fb$^{-1}$ of 7 TeV and 8 TeV data, leading to the following: \begin{eqnarray*} \phi_s & = & -0.087\phantom{0} \pm 0.036\phantom{0} ~\mathrm{(stat.)} \pm 0.021\phantom{0} ~\mathrm{(syst.)~rad} \\ \Delta\Gamma_{s} & = & \phantom{-}0.0657 \pm 0.0043 ~\mathrm{(stat.)} \pm 0.0037 ~\mathrm{(syst.)~ps}^{-1} \\ \Gamma_{s} & = & \phantom{-}0.6703 \pm 0.0014 ~\mathrm{(stat.)} \pm 0.0018 ~\mathrm{(syst.)~ps}^{-1} \\ \end{eqnarray*} Results for $\phi_s$ and $\Delta\Gamma_{s}$ are also presented as 68% confidence level contours in the $\phi_s$-$\Delta\Gamma_{s}$ plane. Furthermore, the transversity amplitudes and corresponding strong phases are measured. $\phi_s$ and $\Delta\Gamma_{s}$ measurements are in agreement with the Standard Model predictions.

9 data tables

Fitted values for the physical parameters of interest with their statistical and systematic uncertainties, for the result of solution (a).

Fitted values for the physical parameters of interest with their statistical and systematic uncertainties, for the result of solution (b).

Fit correlations between the physical parameters of interest, obtained from the fit for solution (a).

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$\rm{K}^{*}(\rm{892})^{0}$ and $\phi(1020)$ production at midrapidity in pp collisions at $\sqrt{s}$ = 8 TeV

The ALICE collaboration Acharya, Shreyasi ; Adamova, Dagmar ; Adhya, Souvik Priyam ; et al.
Phys.Rev.C 102 (2020) 024912, 2020.
Inspire Record 1762364 DOI 10.17182/hepdata.99928

The production of $\mathrm{K}^{*}(\mathrm{892})^{0}$ and $\mathrm{\phi(1020)}$ in pp collisions at $\sqrt{s}$ = 8 TeV was measured using Run 1 data collected by the ALICE collaboration at the LHC. The $p_{\rm{T}}$-differential yields d$^{\rm 2}N$/d$y$d$p_{\rm{T}}$ in the range $0 < p_{\rm{T}} < 20$ GeV/$c$ for $\rm{K}^{*0}$ and $0.4 < p_{\rm{T}} < 16$ GeV/$c$ for $\phi$ have been measured at midrapidity, $|y| < 0.5$. Moreover, improved measurements of the $\rm{K}^{*}(892)^{0}$ and $\phi(1020)$ at $\sqrt{s} = 7$TeV are presented. The collision energy dependence of $p_{\rm{T}}$ distributions, $p_{\rm{T}}$-integrated yields and particle ratios in inelastic pp collisions are examined. The results are also compared with different collision systems. The values of the particle ratios are found to be similar to those measured at other LHC energies. In pp collisions a hardening of the particle spectra is observed with increasing energy, but at the same time it is also observed that the relative particle abundances are independent of the collision energy. The $p_{\rm{T}}$-differential yields of $\rm{K}^{*0}$ and $\phi$ in pp collisions at $\sqrt{s} = 8$ TeV are compared with the expectations of different Monte Carlo event generators.

13 data tables
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Measurement of $K_S^0$ and $\Lambda ^0$ production in $t \bar{t}$ dileptonic events in pp collisions at $\sqrt{s} =$ 7 TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abbott, Dale Charles ; et al.
Eur.Phys.J.C 79 (2019) 1017, 2019.
Inspire Record 1746286 DOI 10.17182/hepdata.91243

Measurements of $K_S^0$ and $\Lambda^0$ production in $t\bar{t}$ final states have been performed. They are based on a data sample with integrated luminosity of 4.6 $\mathrm{fb}^{-1}$ from proton-proton collisions at a centre-of-mass energy of 7 TeV, collected in 2011 with the ATLAS detector at the Large Hadron Collider. Neutral strange particles are separated into three classes, depending on whether they are contained in a jet, with or without a $b$-tag, or not associated with a selected jet. The aim is to look for differences in their main kinematic distributions. A comparison of data with several Monte Carlo simulations using different hadronisation and fragmentation schemes, colour reconnection models and different tunes for the underlying event has been made. The production of neutral strange particles in $t\bar{t}$ dileptonic events is found to be well described by current Monte Carlo models for $K_S^0$ and $\Lambda^0$ production within jets, but not for those produced outside jets.

22 data tables

The transverse momentum ($p_{T}$) distribution for $K^{0}_{S}$ production inside $b$-jets for unfolded data to particle level, normalised to the total number of top pair dileptonic events and scaled to the bin width. The systematic uncertainties are, in order, due to; the MC modelling, the tracking inefficiencies, the jet energy scale (JES), the jet energy resolution (JER), out-of-fiducial events and the unfolding non-closure.

The energy fraction ($x_{K}$) distribution for $K^{0}_{S}$ production inside $b$-jets for unfolded data to particle level, normalised to the total number of top pair dileptonic events and scaled to the bin width. The systematic uncertainties are, in order, due to; the MC modelling, the tracking ineficiencies, the jet energy scale (JES), the jet energy resolution (JER), out-of-fiducial events and the unfolding non-closure.

The energy distribution for $K^{0}_{S}$ production inside $b$-jets for unfolded data to particle level, normalised to the total number of top pair dileptonic events and scaled to the bin width. The systematic uncertainties are, in order, due to; the MC modelling, the tracking ineficiencies, the jet energy scale (JES), the jet energy resolution (JER), out-of-fiducial events and the unfolding non-closure.

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