HEPData Search

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Evidence for the Existence of a New Vector Meson of Mass 1.82-GeV Observed in e+ e- Annihilations at ADONE

Bernabei, R. ; d'Angelo, S. ; Esposito, B. ; et al.

Phys.Lett.B 68 (1977) 389-392, 1977.

Inspire Record 119878 DOI 10.17182/hepdata.27563

Evidence is presented for the occurrence in e + e − annihilation of a new vector meson of mass 1821 ± 16 MeV and Γ = 31 ± 15 MeV.

1 data table match query

Table 1

MULTIHADRON EVENTS (AT LEAST THREE CHARGED TRACKS WITH ZERO OR MORE PHOTONS) PER UNIT LUMINOSITY.

Momentum Analysis of Kaon and Pion Pairs Produced from Timelike Photons at 1.6-GeV Energy

Esposito, B. ; Felicetti, F. ; Marini, A. ; et al.

Phys.Lett.B 67 (1977) 239-242, 1977.

Inspire Record 124109 DOI 10.17182/hepdata.27574

We present results for the total cross section of e + e − annihilation into two hadrons at 1.6 GeV: σ ππ = σ KK = (1.8 ± 1.1) × 10 -33 cm 2 .From these values we obtain the time-like electromagnetic form factors these mesons: | F π | 2 = 0.24 ± 0.14 and | F K | 2 = 0.46 ± 0.26.

1 data table match query

Table 1

No description provided.

Multi-Hadron Production from e+ e- Annihilation at 1.6 Center-of-Mass Energy

Esposito, B. ; Felicetti, F. ; Marini, A. ; et al.

Lett.Nuovo Cim. 19 (1977) 21-31, 1977.

Inspire Record 124164 DOI 10.17182/hepdata.37424

None

2 data tables match query

Table 2

No description provided.

Table 3

No description provided.

Hadronic Cross-section in $e^+ e^-$ Annihilation From 1.45-{GeV} to 1.80-{GeV}

Esposito, B. ; Marini, A. ; Piano Mortari, Giovanni ; et al.

Lett.Nuovo Cim. 30 (1981) 65-71, 1981.

Inspire Record 170172 DOI 10.17182/hepdata.37368

None

2 data tables match query

Table 1

CROSS SECTION EXCLUDES ANY CONTRIBUTION FROM TWO-BODY FINAL STATES (PI+ PI- AND K+ K-).

Table 2

CHARGED AND NEUTRAL MULTIPLICITIES.

Search for lepton-flavor violating decays of the Higgs boson in the $\mu\tau$ and e$\tau$ final states in proton-proton collisions at $\sqrt{s}$ = 13 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.

Phys.Rev.D 104 (2021) 032013, 2021.

Inspire Record 1862497 DOI 10.17182/hepdata.104861

A search is presented for lepton-flavor violating decays of the Higgs boson to $\mu\tau$ and e$\tau$. The data set corresponds to an integrated luminosity of 137 fb$^{-1}$ collected at the LHC in proton-proton collisions at a center-of-mass energy of 13 TeV. No significant excess has been found, and the results are interpreted in terms of upper limits on lepton-flavor violating branching fractions of the Higgs boson. The observed (expected) upper limits on the branching fractions are, respectively, $\mathcal{B}($H $\to\mu\tau)$$\lt$ 0.15 (0.15)% and $\mathcal{B}($H$\to$e$\tau)$ $\lt$ 0.22 (0.16)% at 95% confidence level.

4 data tables match query

Table 1

Observed (expected) 95% CL upper limits on $B(H\to\mu\tau)$ for each individual category and combined

Table 2

Observed (expected) 95% CL upper limits on $B(H\to e\tau)$ for each individual category and combined

Table 3

Summary of observed and expected upper limits at 95% CL, best fit branching fractions and corresponding constraints on Yukawa couplings for the $H\to\mu\tau$ and $H\to e\tau$ channels

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Search for light long-lived neutral particles produced in $pp$ collisions at $\sqrt{s} =$ 13 TeV and decaying into collimated leptons or light hadrons with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abbott, Dale Charles ; et al.

Eur.Phys.J.C 80 (2020) 450, 2020.

Inspire Record 1752519 DOI 10.17182/hepdata.91132

Several models of physics beyond the Standard Model predict the existence of dark photons, light neutral particles decaying into collimated leptons or light hadrons. This paper presents a search for long-lived dark photons produced from the decay of a Higgs boson or a heavy scalar boson and decaying into displaced collimated Standard Model fermions. The search uses data corresponding to an integrated luminosity of 36.1 fb$^{-1}$ collected in proton-proton collisions at $\sqrt{s} =$ 13 TeV recorded in 2015-2016 with the ATLAS detector at the Large Hadron Collider. The observed number of events is consistent with the expected background, and limits on the production cross section times branching fraction as a function of the proper decay length of the dark photon are reported. A cross section times branching fraction above 4 pb is excluded for a Higgs boson decaying into two dark photons for dark-photon decay lengths between 1.5 mm and 307 mm.

19 data tables match query

Table 1

Upper limits at 95% CL on the cross section times branching fraction for the process $H \to 2\gamma_d + X$ with $m_H$ = 125 GeV in the muon-muon final state.

Table 2

Upper limits at 95% CL on the cross section times branching fraction for the process $H \to 4\gamma_d + X$ with $m_H$ = 125 GeV in the muon-muon final state.

Table 3

Upper limits at 95% CL on the cross section times branching fraction for the process $H \to 2\gamma_d + X$ with $m_H$ = 800 GeV in the muon-muon final state.