Hypertriton production in p-Pb collisions at $\sqrt{s_{\rm{NN}}}$ = 5.02 TeV

The A Large Ion Collider Experiment & ALICE collaborations Acharya, Shreyasi ; Adamova, Dagmar ; Adler, Alexander ; et al.
Phys.Rev.Lett. 128 (2022) 252003, 2022.
Inspire Record 1889905 DOI 10.17182/hepdata.130967

The study of nuclei and antinuclei production has proven to be a powerful tool to investigate the formation mechanism of loosely bound states in high-energy hadronic collisions. The first measurement of the production of ${\rm ^{3}_{\Lambda}\rm H}$ in p-Pb collisions at $\sqrt{s_{\rm{NN}}}$ = 5.02 TeV is presented in this Letter. Its production yield measured in the rapidity interval $-1 < y < 0$ for the 40% highest multiplicity p-Pb collisions is ${\rm d} N /{\rm d} y =[\mathrm{6.3 \pm 1.8 (stat.) \pm 1.2 (syst.) ] \times 10^{-7}}$. The measurement is compared with the expectations of statistical hadronisation and coalescence models, which describe the nucleosynthesis in hadronic collisions. These two models predict very different yields of the hypertriton in charged particle multiplicity environments relevant to small collision systems such as p-Pb and therefore the measurement of ${\rm d} N /{\rm d} y$ is crucial to distinguish between them. The precision of this measurement leads to the exclusion with a significance larger than 6.9$\sigma$ of some configurations of the statistical hadronization model, thus constraining the theory behind the production of loosely bound states at hadron colliders.

3 data tables

Integrated yield of hypertriton produced in 0-40% p-Pb collisions

Hypertriton over $\Lambda$ ratio in 0-40% p-Pb collisions

$S_3$ in the 40% largest multiplicity p-Pb collisions


Measurement of very forward energy and particle production at midrapidity in pp and p-Pb collisions at the LHC

The ALICE collaboration Acharya, Shreyasi ; Adamova, Dagmar ; Adler, Alexander ; et al.
JHEP 08 (2022) 086, 2022.
Inspire Record 1890061 DOI 10.17182/hepdata.131521

The energy deposited at very forward rapidities (very forward energy) is a powerful tool for characterising proton fragmentation in pp and p$-$Pb collisions. The correlation of very forward energy with particle production at midrapidity provides direct insights into the initial stages and the subsequent evolution of the collision. Furthermore, the correlation with the production of particles with large transverse momenta at midrapidity provides information complementary to the measurements of the underlying event, which are usually interpreted in the framework of models implementing centrality-dependent multiple parton interactions. Results about very forward energy, measured by the ALICE zero degree calorimeters (ZDCs), and its dependence on the activity measured at midrapidity in pp collisions at $\sqrt{s}=13$ TeV and in p$-$Pb collisions at $\sqrt{s_{\rm{NN}}}=8.16$ TeV are discussed. The measurements performed in pp collisions are compared with the expectations of three hadronic interaction event generators: PYTHIA 6 (Perugia 2011 tune), PYTHIA 8 (Monash tune), and EPOS LHC. These results provide new constraints on the validity of models in describing the beam remnants at very forward rapidities, where perturbative QCD cannot be used.

16 data tables

Average signal on A-side vs. C-side ZN in pp collisions at 13 TeV

Average signal on A-side vs. C-side ZP in pp collisions at 13 TeV

Pb-remnant side ZN signal normalized to MB value vs. ZN centrality percentile in p-Pb collisions at 5.02 TeV

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Measurement of the production cross section of pairs of isolated photons in $pp$ collisions at 13 TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Braden Keim ; Abbott, Dale ; et al.
JHEP 11 (2021) 169, 2021.
Inspire Record 1887997 DOI 10.17182/hepdata.104925

A measurement of prompt photon-pair production in proton-proton collisions at $\sqrt{s}=13$ TeV is presented. The data were recorded by the ATLAS detector at the LHC with an integrated luminosity of 139 fb$^{-1}$. Events with two photons in the well-instrumented region of the detector are selected. The photons are required to be isolated and have a transverse momentum of $p_\mathrm{T,\gamma_{1(2)}} > 40(30)$ GeV for the leading (sub-leading) photon. The differential cross sections as functions of several observables for the diphoton system are measured and compared with theoretical predictions from state-of-the-art Monte Carlo and fixed-order calculations. The QCD predictions from next-to-next-to-leading-order calculations and multi-leg merged calculations are able to describe the measured integrated and differential cross sections within uncertainties, whereas lower-order calculations show significant deviations, demonstrating that higher-order perturbative QCD corrections are crucial for this process. The resummed predictions with parton showers additionally provide an excellent description of the low transverse-momentum regime of the diphoton system.

9 data tables

Differential cross section as a function of $p_{T,\gamma_{1}}$. The table contains the values measured in data and theory predictions from SHERPA, DIPHOX and NNLOJET.

Differential cross section as a function of $p_{T,\gamma_{2}}$. The table contains the values measured in data and theory predictions from SHERPA, DIPHOX and NNLOJET.

Integrated fiducial cross section measured in data and from different predictions.

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Search for exotic decays of the Higgs boson into long-lived particles in $pp$ collisions at $\sqrt{s} = 13$ TeV using displaced vertices in the ATLAS inner detector

The ATLAS collaboration Aad, Georges ; Abbott, Braden Keim ; Abbott, Dale ; et al.
JHEP 11 (2021) 229, 2021.
Inspire Record 1882568 DOI 10.17182/hepdata.106655

A novel search for exotic decays of the Higgs boson into pairs of long-lived neutral particles, each decaying into a bottom quark pair, is performed using 139 fb$^{-1}$ of $\sqrt{s} = 13$ TeV proton-proton collision data collected with the ATLAS detector at the LHC. Events consistent with the production of a Higgs boson in association with a leptonically decaying $Z$ boson are analysed. Long-lived particle (LLP) decays are reconstructed from inner-detector tracks as displaced vertices with high mass and track multiplicity relative to Standard Model processes. The analysis selection requires the presence of at least two displaced vertices, effectively suppressing Standard Model backgrounds. The residual background contribution is estimated using a data-driven technique. No excess over Standard Model predictions is observed, and upper limits are set on the branching ratio of the Higgs boson to LLPs. Branching ratios above 10% are excluded at 95% confidence level for LLP mean proper lifetimes $c\tau$ as small as 4 mm and as large as 100 mm. For LLP masses below 40 GeV, these results represent the most stringent constraint in this lifetime regime.

7 data tables

95% CL exclusion limits on $\mathcal{B}(H\rightarrow aa \rightarrow b\bar{b}b\bar{b})$ for $m_a = 16$ GeV.

95% CL exclusion limits on $\mathcal{B}(H\rightarrow aa \rightarrow b\bar{b}b\bar{b})$ for $m_a = 25$ GeV.

95% CL exclusion limits on $\mathcal{B}(H\rightarrow aa \rightarrow b\bar{b}b\bar{b})$ for $m_a = 35$ GeV.

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Version 2
Search for long-lived particles decaying in the CMS endcap muon detectors in proton-proton collisions at $\sqrt{s} = $ 13 TeV

The CMS collaboration Tumasyan, Armen ; Adam, Wolfgang ; Andrejkovic, Janik Walter ; et al.
Phys.Rev.Lett. 127 (2021) 261804, 2021.
Inspire Record 1883075 DOI 10.17182/hepdata.104408

A search for long-lived particles (LLPs) produced in decays of standard model (SM) Higgs bosons is presented. The data sample consists of 137 fb$^{-1}$ of proton-proton collisions at $\sqrt{s} =$ 13 TeV, recorded at the LHC in 2016-2018. A novel technique is employed to reconstruct decays of LLPs in the endcap muon detectors. The search is sensitive to a broad range of LLP decay modes and to masses as low as a few GeV. No excess of events above the SM background is observed. The most stringent limits to date on the branching fraction of the Higgs boson to LLPs subsequently decaying to quarks and $\tau^+\tau^-$ are found for proper decay lengths greater than 6, 20, and 40 m, for LLP masses of 7, 15, and 40 GeV, respectively.

29 data tables

The 95% CL observed and expected limits on the branching fraction B(H $\rightarrow$ SS) for 7 GeV mass and $ S \rightarrow d\bar{d}$ decay mode.

The 95% CL observed and expected limits on the branching fraction B(H $\rightarrow$ SS) for 7 GeV mass and $ S \rightarrow d\bar{d}$ decay mode.

The 95% CL observed and expected limits on the branching fraction B(H $\rightarrow$ SS) for 15 GeV mass and $ S \rightarrow d\bar{d}$ decay mode.

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Measurement of prompt open-charm production cross sections in proton-proton collisions at $\sqrt{s} = $ 13 TeV

The CMS collaboration Tumasyan, Armen ; Adam, Wolfgang ; Ambrogi, Federico ; et al.
JHEP 11 (2021) 225, 2021.
Inspire Record 1876550 DOI 10.17182/hepdata.104924

The production cross sections for prompt open-charm mesons in proton-proton collisions at a center-of-mass energy of 13 TeV are reported. The measurement is performed using a data sample collected by the CMS experiment corresponding to an integrated luminosity of 29 nb$^{-1}$. The differential production cross sections of the D$^{*\pm}$, D$^\pm$, and D$^0$ ($\overline{\mathrm{D}}^{0}$) mesons are presented in ranges of transverse momentum and pseudorapidity 4 $\lt$$p_\mathrm{T}$$\lt$ 100 GeV and $\lvert\eta\rvert$$\lt$ 2.1, respectively. The results are compared to several theoretical calculations and to previous measurements.

2 data tables

The differential cross sections of prompt D^{*+} plus D^{*-}, D0 + bar{D0}, and D+ + D-production in pT bins with |eta| < 2.1;the first uncertainty is statistical, the second is systematic.

The differential cross sections of prompt D^{*+} plus D^{*-}, D0 + bar{D0}, and D+ + D-production in |eta| bins with 4 < pT < 100 GeV;the first uncertainty is statistical, the second is systematic.


Version 2
Measurement of the inclusive and differential $\mathrm{t\overline{t}}\gamma$ cross sections in the single-lepton channel and EFT interpretation at $\sqrt{s}$ = 13 TeV

The CMS collaboration Tumasyan, Armen ; Adam, Wolfgang ; Andrejkovic, Janik Walter ; et al.
JHEP 12 (2021) 180, 2021.
Inspire Record 1876579 DOI 10.17182/hepdata.102876

The production cross section of a top quark pair in association with a photon is measured in proton-proton collisions at a center-of-mass energy of 13 TeV. The data set, corresponding to an integrated luminosity of 137 fb$^{-1}$, was recorded by the CMS experiment during the 2016-2018 data taking of the LHC. The measurements are performed in a fiducial volume defined at the particle level. Events with an isolated, highly energetic lepton, at least three jets from the hadronization of quarks, among which at least one is b tagged, and one isolated photon are selected. The inclusive fiducial $\mathrm{t\overline{t}}\gamma$ cross section, for a photon with transverse momentum greater than 20 GeV and pseudorapidity $\lvert \eta\rvert$$\lt$ 1.4442, is measured to be 798 $\pm$ 7 (stat) $\pm$ 48 (syst) fb, in good agreement with the prediction from the standard model at next-to-leading order in quantum chromodynamics. The differential cross sections are also measured as a function of several kinematic observables and interpreted in the framework of the standard model effective field theory (EFT), leading to the most stringent direct limits to date on anomalous electromagnetic dipole moment interactions of the top quark and the photon.

80 data tables

Distribution of $p_{T}(\gamma)$ in the $N_{jet}\geq 3$ signal region.

Distribution of $p_{T}(\gamma)$ in the $N_{jet}\geq 3$ signal region.

Distribution of $m_{T}(W)$ in the $N_{jet}\geq 3$ signal region.

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Measurements of the electroweak diboson production cross sections in proton-proton collisions at $\sqrt{s} =$ 5.02 TeV using leptonic decays

The CMS collaboration Tumasyan, Armen ; Adam, Wolfgang ; Andrejkovic, Janik Walter ; et al.
Phys.Rev.Lett. 127 (2021) 191801, 2021.
Inspire Record 1876311 DOI 10.17182/hepdata.107754

The first measurements of diboson production cross sections in proton-proton interactions at a center-of-mass energy of 5.02 TeV are reported. They are based on data collected with the CMS detector at the LHC, corresponding to an integrated luminosity of 302 pb$^{-1}$. Events with two, three, or four charged light leptons (electrons or muons) in the final state are analyzed. The WW, WZ, and ZZ total cross sections are measured as $\sigma_\mathrm{WW} =$ 37.0 $^{+5.5}_{-5.2}$ (stat) $^{+2.7}_{-2.6}$ (syst) pb, $\sigma_\mathrm{WZ} =$ 6.4 $^{+2.5}_{-2.1}$ (stat) $^{+0.5}_{-0.3}$ (syst) pb, and $\sigma_\mathrm{ZZ} =$ 5.3 $^{+2.5}_{-2.1}$ (stat) $^{+0.5}_{-0.4}$ (syst) pb. All measurements are in good agreement with theoretical calculations at combined next-to-next-to-leading order quantum chromodynamics and next-to-leading order electroweak accuracy.

5 data tables

Expected event yields in the WW SR and observed number of events. The uncertainties correspond to the statistical and systematic component, respectively.

Expected event yields for the signal and total background in the WZ and ZZ SRs, and observed number of events. The uncertainties correspond to the statistical and systematic component, respectively.

Distribution of the dilepton pT in the WW signal region. Events from DY, conversions, and diboson processes are grouped into the 'Others' category. The vertical error bars represent the statistical uncertainty in the data and the shaded band the uncertainty in the prediction. The signal contributions are scaled to the measured cross sections (postfit).

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Production of K$^{*}(892)^{0}$ and $\phi(1020)$ in pp and Pb-Pb collisions at $\sqrt{s_{\rm NN}} = 5.02$ TeV

The ALICE collaboration Acharya, Shreyasi ; Adamova, Dagmar ; Adler, Alexander ; et al.
Phys.Rev.C 106 (2022) 034907, 2022.
Inspire Record 1870141 DOI 10.17182/hepdata.140098

The production of K$^{*}(892)^{0}$ and $\phi(1020)$ mesons in proton-proton (pp) and lead-lead (Pb-Pb) collisions at $\sqrt{s_\mathrm{NN}} = 5.02$ TeV has been measured using the ALICE detector at the Large Hadron Collider (LHC). The transverse momentum ($p_{\mathrm{T}}$) distributions of K$^{*}(892)^{0}$ and $\phi(1020)$ mesons have been measured at midrapidity $(|y|<0.5)$ up to $p_{\mathrm{T}} = 20$ GeV$/c$ in inelastic pp collisions and for several Pb-Pb collision centralities. The collision centrality and collision energy dependence of the average transverse momenta agree with the radial flow scenario observed with stable hadrons, showing that the effect is stronger for more central collisions and higher collision energies. The $\mathrm{K^{*0}/K}$ ratio is found to be suppressed in Pb-Pb collisions relative to pp collisions: this indicates a loss of the measured K$^{*}(892)^{0}$ signal due to rescattering of its decay products in the hadronic phase. In contrast, for the longer-lived $\phi(1020)$ mesons, no such suppression is observed. The nuclear modification factors ($R_{\rm AA}$) of K$^{*}(892)^{0}$ and $\phi(1020)$ mesons are calculated using pp reference spectra at the same collision energy. In central Pb-Pb collisions for $p_{\rm T} > 8$ GeV$/c$, the $R_{\rm AA}$ values of K$^{*}(892)^{0}$ and $\phi(1020)$ are below unity and observed to be similar to those of pions, kaons, and (anti)protons. The $R_{\rm AA}$ values at high $p_{\mathrm T}$ ($>$~8 GeV$/c$) for K$^{*}(892)^{0}$ and $\phi(1020)$ mesons are in agreement within uncertainties for $\sqrt{s_\mathrm{NN}} = 5.02$ and 2.76 TeV.

22 data tables

$p_{T}$-dependent nuclear modification factor of $\rm{K}^{*0}$ (average of particle and anti-particle) meson measured in 0-10% centrality class for Pb-Pb collisions at $\sqrt{s_{NN}}$ = 5.02 TeV.

$p_{T}$-dependent nuclear modification factor of $\rm{K}^{*0}$ (average of particle and anti-particle) meson measured in 10-20% centrality class for Pb-Pb collisions at $\sqrt{s_{NN}}$ = 5.02 TeV.

$p_{T}$-dependent nuclear modification factor of $\rm{K}^{*0}$ (average of particle and anti-particle) meson measured in 20-30% centrality class for Pb-Pb collisions at $\sqrt{s_{NN}}$ = 5.02 TeV.

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Fragmentation of jets containing a prompt J$/\psi$ meson in PbPb and pp collisions at $\sqrt{s_\mathrm{NN}} =$ 5.02 TeV

The CMS collaboration Tumasyan, Armen ; Adam, Wolfgang ; Bergauer, Thomas ; et al.
Phys.Lett.B 825 (2022) 136842, 2022.
Inspire Record 1870319 DOI 10.17182/hepdata.95234

Jets containing a prompt J$/\psi$ meson are studied in lead-lead collisions at a nucleon-nucleon center-of-mass energy of 5.02 TeV, using the CMS detector at the LHC. Jets are selected to be in the transverse momentum range of 30 $\lt$$p_\mathrm{T}$$\lt$ 40 GeV. The J$/\psi$ yield in these jets is evaluated as a function of the jet fragmentation variable $z$, the ratio of the J$/\psi$$p_\mathrm{T} $ to the jet $p_\mathrm{T}$. The nuclear modification factor, $R_\mathrm{AA}$, is then derived by comparing the yield in lead-lead collisions to the corresponding expectation based on proton-proton data, at the same nucleon-nucleon center-of-mass energy. The suppression of the J$/\psi$ yield shows a dependence on $z$, indicating that the interaction of the J$/\psi$ with the quark-gluon plasma formed in heavy ion collisions depends on the fragmentation that gives rise to the J$/\psi$ meson.

4 data tables

Normalized $z$ distribution in pp collisions.

The J/$\psi$ differential cross section in pp and the $T_{AA}$-scaled yield in PbPb collisions, as a function of $z$.

The nuclear modification factor R$_{\rm AA}$, as a function of $z$.

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