Study of the process e+e−→K+K− in the center-of-mass energy range 1010–1060 MeV with the CMD-3 detector

Kozyrev, E. A.; Solodov, E. P.; Akhmetshin, R.R.; Amirkhanov, A.N.; Anisenkov, A. V.; Aulchenko, V.; Banzarov, V.Sh.; Bashtovoy, N.S.; Berkaev, D. E.; Bondar, A.; Bragin, A.V.; Eidelman, S.; Epifanov, D.; Epshteyn, L.B.; Erofeev, A.L.; Fedotovich, G.V.; Gayazov, S.E.; Grebenuk, A.A.; Gribanov, S.S.; Grigoriev, D.N.; Ignatov, F.V.; Иванов, В. Л.; Karpov, S. V.; Kasaev, A. S.; Казанин, В. Ф.; Korobov, A.; Koop, I. A.; Kozyrev, Aleksei; Krokovny, P.; Kuzmenko, A.E.; Kuzmin, A.; Logashenko, I.B.; Lukin, P.; Лысенко, А. П.; Mikhailov, K.; Okhapkin, V.S.; Perevedentsev, E. A.; Pestov, Y.; Попов, А. С.; Razuvaev, G.P.; Rogovsky, Yu. A.; Рубан, А.А.; Ryskulov, N.M.; Ryzhenenkov, A.E.; Shebalin, V.; Shemyakin, D.N.; Shwartz, B.; Shwartz, D. B.; Sibidanov, A.; Shatunov, Yu. M.; Talyshev, A. A.; Воробйов, А.І.; Yudin, Yu.V.

doi:10.1016/j.physletb.2018.01.079

Cited by 44 publications

(56 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The hadronic part is obtained from a numerical integration over See text for a description of the data used. Middle: comparison between individual e + e − → K + K − cross-section measurements from BABAR [39], CMD-2 [40], CMD-3 [38] and SND [37], and the HVPTools combination. Bottom: local scale factor versus centre-of-mass energy applied to the combined K + K − cross-section uncertainty to account for inconsistency in the individual measurements.…”

Section: Compilation and Resultsmentioning

confidence: 99%

See 1 more Smart Citation

A new evaluation of the hadronic vacuum polarisation contributions to the muon anomalous magnetic moment and to $$\varvec{\alpha }({{\varvec{m}}}_{{\varvec{Z}}}^2)$$

et al. 2020

View full text Add to dashboard Cite

We reevaluate the hadronic vacuum polarisation contributions to the muon magnetic anomaly and to the running of the electromagnetic coupling constant at the Z-boson mass. We include newest e + e − → hadrons cross-section data together with a phenomenological fit of the threshold region in the evaluation of the dispersion integrals. The precision in the individual datasets cannot be fully exploited due to discrepancies that lead to additional systematic uncertainty in particular between BABAR and KLOE data in the dominant π + π − channel. For the muon (g − 2)/2, we find for the lowest-order hadronic contribution (693.9 ± 4.0) · 10 −10 . The full Standard Model prediction differs by 3.3σ from the experimental value. The five-quark hadronic contribution to α(m 2 Z ) is evaluated to be (276.1 ± 1.0) · 10 −4 .

show abstract

Section: Compilation and Resultsmentioning

confidence: 99%

“…Previously, a 5.1% difference between CMD-2 at VEPP-2M and BABAR, with the CMD-2 data being lower, was observed. New results from CMD-3 at VEPP-2000 [38] exhibit the opposite effect: they are 5.5% higher than BABAR (cf. Fig.…”

Section: The K + K − Channelmentioning

confidence: 97%

A new evaluation of the hadronic vacuum polarisation contributions to the muon anomalous magnetic moment and to $$\varvec{\alpha }({{\varvec{m}}}_{{\varvec{Z}}}^2)$$

et al. 2020

View full text Add to dashboard Cite

show abstract

“…The analysis in Section 16 has shown that the SND, BaBar [76] and the updated [75] CMD-2 data are in fairly good agreement with each other and accommodate easily the HLS context where all other kinds of data are encompassed. Tension has indeed been observed between the CMD-3 data [77,79] and the other samples. This tension has been traced back to the offdiagonal part of the CMD-3 error covariance matrices for both the K + K − and K L K S spectra; this analysis is summarized by Table 2.…”

Section: Figures 2 3 and 4 Together Withmentioning

confidence: 71%

“…Instead, the BS fit performed when discarding the τ data leads to a picture in good correspondence with the RS fit results already commented; indeed, the partial χ 2 's reported in the second data column of Table 3 are similar to those obtained by fitting with the RS variant of the BHLS 2 model. Nevertheless, some tension survives in the 3-pion sector while the dipion 33 The issue between BaBar and CMD-3 charged kaon data has already been noted in [77]. 34 One should note the smaller number of data points considered in the fit procedure for the π + π − π 0 annihilation channel, because of excluding the data points from the φ region.…”

Section: Fit Properties Of the Various Broken Hls Modelsmentioning

confidence: 97%

“…As for the K + K − channel : In its [77], the CMD-3 Collaboration points toward disagreements with both the BaBar [76] and the original CMD-2 data samples [73]. Once the correction factor (1.094 ± 0.040) for the trigger efficiency of CMD-2 is applied, the discrepancy between the CMD-3 and CMD-2 K + K − samples looks much reduced [75] -possibly washed out.…”

Section: Preliminary Remarksmentioning

confidence: 99%

See 1 more Smart Citation

$${\hbox {BHLS}}_2$$, a new breaking of the HLS model and its phenomenology

2020

View full text Add to dashboard Cite

Previous studies have shown that the Hidden Local Symmetry (HLS) Model, supplied with appropriate symmetry breaking mechanisms, provides an Effective Lagrangian (BHLS) able to encompass a large number of processes within a unified framework. This allowed to design a global fit procedure which provides a fair simultaneous description of the e + e − annihilation into 6 final states (π + π − , π 0 γ, ηγ, π + π − π 0 , K + K − , K L K S ), the dipion spectrum in the τ decay and some more light meson decay partial widths. In this paper, additional breaking schemes are defined which improve the BHLS working and extend its scope so as to absorb spacelike processes within a new framework (BHLS 2 ). The phenomenology previously explored with BHLS is fully revisited in the BHLS 2 context with special emphasis on the φ mass region using all available data samples. It is shown that BHLS 2 addresses perfectly the close spacelike region covered by NA7 and Fermilab data; it is also shown that the recent Lattice QCD (LQCD) information on the pion form factor are accurately predicted by the BHLS 2 fit functions derived from fits to only annihilation data. The contribution to the muon anomalous magnetic moment a th 1 The e + e − → η ′ γ channel has been considered in [25,26] and found to contributes to a had µ at the 10 −12 level only and can thus be safely discarded.As clear in Equations (8), BKY breaks the symmetry of the HLS Model in the very definition of its Lagrangian. This is quite legitimate and strongly validated by its remarkable description of a considerable amount of data [25,26,27]. Nevertheless, it is of interest to explore other possibilities to improve the description of the data in some specific mass regions and, then, reduce or cancel out the additional systematic uncertainties reported in [27].Let us focus on Equation (4) which defines the original HLS covariant derivative :

show abstract

Two and three pseudoscalar production in e+e− annihilation and their contributions to (g − 2)μ

Qin

Dai

Portolés

2021

J. High Energ. Phys.

View full text Add to dashboard Cite

A coherent study of e+e− annihilation into two (π+π−, K+K−) and three (π+π−π0, π+π−η) pseudoscalar meson production is carried out within the framework of resonance chiral theory in energy region E ≲ 2 GeV. The work of [L.Y. Dai, J. Portolés, and O. Shekhovtsova, Phys. Rev. D88 (2013) 056001] is revisited with the latest experimental data and a joint analysis of two pseudoscalar meson production. Hence, we evaluate the lowest order hadronic vacuum polarization contributions of those two and three pseudoscalar processes to the anomalous magnetic moment of the muon. We also estimate some higher-order additions led by the same hadronic vacuum polarization. Combined with the other contributions from the standard model, the theoretical prediction differs still by (21.6 ± 7.4) × 10−10 (2.9σ) from the experimental value.

show abstract

Study of the process e+e−→K+K− in the center-of-mass energy range 1010–1060 MeV with the CMD-3 detector

Cited by 44 publications

References 17 publications

A new evaluation of the hadronic vacuum polarisation contributions to the muon anomalous magnetic moment and to $$\varvec{\alpha }({{\varvec{m}}}_{{\varvec{Z}}}^2)$$

A new evaluation of the hadronic vacuum polarisation contributions to the muon anomalous magnetic moment and to $$\varvec{\alpha }({{\varvec{m}}}_{{\varvec{Z}}}^2)$$

$${\hbox {BHLS}}_2$$, a new breaking of the HLS model and its phenomenology

Two and three pseudoscalar production in e+e− annihilation and their contributions to (g − 2)μ

Contact Info

Product

Resources

About