E+ e- annihilation into two hadrons in the energy interval 1400-2400 mev

Alles-Borelli, V. ; Bernardini, M. ; Bollini, D. ; et al.
Phys.Lett.B 40 (1972) 433-436, 1972.
Inspire Record 75693 DOI 10.17182/hepdata.28268

The proof is given for the existence of the reaction e + e − → h ± h ∓ in the energy range 1400–2400 MeV, and its energy dependence is compared with that of e + e − → e ± e ∓ , in the same experimental conditions of observation. The exponent of the s -dependence of the ratio α = (e + e − → h ± h ∓ )/ (e + e − → e ± e ∓ ) is measured to be n = 2.08 ± 0.45, in the s -range (1.96 − 5.76) GeV 2 , on the basis of 51 e + e − → h ± h ∓ events and 8918 e + e − → e ± e ∓ events observed.

1 data table match query

CROSS SECTION FOR PRODUCTION OF CHARGED HADRON PAIRS.


Proof of comparable K pair and pi pair production from time-like photons of 1.5-GeV, 1.6-GeV, and 1.7-GeV and determination of the K meson electromagnetic form factor.

Bernardini, M. ; Bollini, D. ; Brunini, P.L. ; et al.
Phys.Lett.B 44 (1973) 393-396, 1973.
Inspire Record 85276 DOI 10.17182/hepdata.28101

The observation of 21 K + K − pairs in 38 hadron pair events produced at 1.5, 1.6, and 1.7 GeV total centre-of-mass energies in e + e − annihilations, establishes that time-like photons produce K pairs and π pairs with comparable rates in this energy range. The K-meson electromagnetic form factor at a mean s -value of 2.4 GeV 2 is measured to be | F K | = 0.50±0.08. The number of e + e − pairs observed in the same angular and energy range is 5148.

1 data table match query

No description provided.


Version 2
Measurements of sigma(e+ e- --> mu+- mu-+) in the energy range 1.2-GeV to 3.0-GeV.

Alles-Borelli, V. ; Bernardini, M. ; Bollini, D. ; et al.
Phys.Lett.B 59 (1975) 201, 1975.
Inspire Record 99248 DOI 10.17182/hepdata.27778

The analysis of 1466 events of the type e + e − → μ ± μ ± , in the time-lifke range from 1.44 to 9.00 GeV 2 , sh that the absolute value of the cross-section and its energy dependence follow QED expectations within (± 3.2%) and (± 1.2%), respectively.

1 data table match query

The cross section of the reaction $e^+ e^- \to \mu^\pm \mu^\mp$ integrated over the experimental apparatus at 14 values of the colliding beam energy $E$ corresponding to total centre-of-mass energy $\sqrt{s}=2E$ from 1.2 to 3.0 GeV.


A Study of the Hadronic Angular Distribution in (e+ e-) Processes from 1.2-GeV to 3.0-GeV

Bernardini, M. ; Bollini, D. ; Brunini, P.L. ; et al.
Nuovo Cim.A 26 (1975) 163, 1975.
Inspire Record 91111 DOI 10.17182/hepdata.37720

The angular distribution of 2720 tracks of 1085 hadronic final states produced from (e+e-) annihilation has been studied in the 1.2 to 3.0 GeV total centre-of-mass energy range. If we parametrize the angular distribution in terms off(θ) =1 + A cos2 θ, where 6 is the angle between the hadronic track produced and the colliding-beam direction, the results show thatA is less than 0.21, with 90% confidence.

1 data table match query

ANGULAR DISTRIBUTION OF CHARGED HADRONS FOUND TO BE 1 + (0.07 +- 0.11)*(COS(THETA)**2).


The time-like electromagnetic form factors of the charged pseudoscalar mesons from 1.44-GeV**2 to 9.0-GeV**2.

Bernardini, M. ; Bollini, D. ; Brunini, P.L. ; et al.
Phys.Lett.B 46 (1973) 261-264, 1973.
Inspire Record 85277 DOI 10.17182/hepdata.28063

The study of 620 hadron pairs produced in the s -range (1.44−9.0) GeV 2 , has yielded 110 collinear hadronic events. Their identification in terms of π and K mesons allows the determination of the time-like electromagnetic from factors of these pseudoscalar mesons in the above time-like range. The total number of (e + e − ) events observed in the same experimental conditions is 18 048.

2 data tables match query

No description provided.

No description provided.


Cross-Section Measurements for the Exclusive Reaction e+ e- --> 4 pi+- in the Energy Range 1.2-GeV to 3.0-GeV

Bernardini, M. ; Bollini, D. ; Brunini, P.L. ; et al.
Phys.Lett.B 53 (1974) 384-386, 1974.
Inspire Record 90250 DOI 10.17182/hepdata.27914

We have measured the crosss section for the reaction e + e − → 4 π ± in the energy range 1 2–3.0 GeV.No statistically significant evidence for a new vector meson in the ϱ″ region is found.

1 data table match query

No description provided.


The Energy Dependence of Sigma (e+ e- --> Hadrons) in the Total Center-Of-Mass Energy Range 1.2-GeV to 3.0-GeV

Bernardini, M. ; Bollini, D. ; Brunini, P.L. ; et al.
Phys.Lett.B 51 (1974) 200-204, 1974.
Inspire Record 89816 DOI 10.17182/hepdata.27933

We have observed 1085 events of the type e + e − → hadrons, in the total centre-of-mass energy range √ s = 1.2 to 3.0 GeV. The energy dependence of the total annihilation cross-section, parametrized in the form σ ( e + e − → hadrons ) = A · s n , is measured to be n = -(1.54 −0.29 +0.17 ) in the above energy range.

4 data tables match query

RESULTS USING THE (AP P) MODEL WITH PHASE-SPACE CORRECTIONS.

R AS CALCULATED FROM THE TOTAL HADRONIC CROSS SECTION USING THE (AP P) MODEL.

TOTAL CROSS SECTIONS OBTAINED USING THE QUASI-MODEL-INDEPENDENT METHOD ARE TABULATED HERE.

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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

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

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

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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Precise determination of the B0s-B0sbar oscillation frequency

The LHCb collaboration Aaij, R. ; Beteta, C. Abellán ; Ackernley, T. ; et al.
Nature Phys. 18 (2022) 1-5, 2022.
Inspire Record 1857623 DOI 10.17182/hepdata.105881

Mesons comprising a beauty quark and a strange quark can oscillate between particle (B0s) and antiparticle (B0s) flavour eigenstates, with a frequency given by the mass difference between heavy and light mass eigenstates, deltams. Here we present ameasurement of deltams using B0s2DsPi decays produced in proton-proton collisions collected with the LHCb detector at the Large Hadron Collider. The oscillation frequency is found to be deltams = 17.7683 +- 0.0051 +- 0.0032 ps-1, where the first uncertainty is statistical and the second systematic. This measurement improves upon the current deltams precision by a factor of two. We combine this result with previous LHCb measurements to determine deltams = 17.7656 +- 0.0057 ps-1, which is the legacy measurement of the original LHCb detector.

1 data table match query

Summary of LHCb measurements. Comparison of LHCb $\Delta m_s$ measurements from Refs. [8–11], the result presented in this article and their average. For the average, following systematic uncertainties are assumed to be fully correlated(:) zScale, MomentumScale, VeloAlignment and DecayTimeBias. The measurements are statistically uncorrelated.


Proton compton effect

Bernardini, G. ; Hanson, A.O. ; Odian, A.C. ; et al.
Nuovo Cim. 18 (1960) 1203-1236, 1960.
Inspire Record 1184998 DOI 10.17182/hepdata.37758

The elastic scattering of photons by protons has been measured for 100 MeV to 290 MeV photons at 90° c.m.s. and 139° c.m.s. scattering angles. The expected large increase in cross-section is observed at energies approaching that of (3/2, 3/2) pion-nucleon resonance. The scattering can be qualitatively explained by the ordinary Thomson amplitude combined with that of the (3/2, 3/2) resonance. A more detailed examination of the cross-section in the region just above the photo-meson threshold has shown that it is sensitive to the π0 photon coupling. From the experimental data, one may conclude that the π0 mean life should be between 10−16 and 10−18 s.

1 data table match query

No description provided.