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result(s) for
"Malaescu, B"
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A new evaluation of the hadronic vacuum polarisation contributions to the muon anomalous magnetic moment and to α(mZ2)
by
Malaescu, B.
,
Hoecker, A.
,
Zhang, Z.
in
Astronomy
,
Astrophysics and Cosmology
,
Electromagnetic coupling
2020
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
(
694.0
±
4.0
)
·
10
-
10
. The full Standard Model prediction differs by
3.3
σ
from the experimental value. The five-quark hadronic contribution to
α
(
m
Z
2
)
is evaluated to be
(
276.0
±
1.0
)
·
10
-
4
.
Journal Article
Reevaluation of the hadronic vacuum polarisation contributions to the Standard Model predictions of the muon g-2 and α(mZ2) using newest hadronic cross-section data
by
Malaescu, B.
,
Hoecker, A.
,
Zhang, Z.
in
Astronomy
,
Astrophysics and Cosmology
,
Cross-sections
2017
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 (among others) from the BABAR and VEPP-2000 experiments. For the muon
(
g
-
2
)
/
2
we find for the lowest-order hadronic contribution
(
693.1
±
3.4
)
×
10
-
10
, improving the precision of our previous evaluation by 21%. The full Standard Model prediction differs by
3.5
σ
from the experimental value. The five-quark hadronic contribution to
α
(
m
Z
2
)
is evaluated to be
(
276.0
±
0.9
)
×
10
-
4
.
Journal Article
Reevaluation of the hadronic contributions to the muon g−2 and to$\\alpha (M^{2}_{Z})
by
Malaescu, B.
,
Hoecker, A.
,
Zhang, Z.
in
Analysis
,
Electromagnetism
,
Exact sciences and technology
2011
We reevaluate the hadronic contributions to the muon magnetic anomaly, and to the running of the electromagnetic coupling constant at the Z-boson mass. We include new [π.sup.+][π.sup.-] cross-section data from KLOE, all available multi-hadron data from BABAR, a reestimation of missing low-energy contributions using results on cross sections and process dynamics from BABAR, a reevaluation of all experimental contributions using the software package HVPTools together with a reanalysis of inter-experiment and inter-channel correlations, and a reevaluation of the continuum contributions from perturbative QCD at four loops. These improvements lead to a decrease in the hadronic contributions with respect to earlier evaluations. For the muon g-2 we find lowest-order hadronic contributions of (692.3 ± 4.2) x [10.sup.-10] and (701.5 ± 4.7) x [10.sup.-10] for the [e.sup.+][e.sup.-]-based and r -based analyses, respectively, and full Standard Model predictions that differ by 3.6σ and 2.4σ from the experimental value. For the [e.sup.+][e.sup.-]-based five-quark hadronic contribution to a(M|) we find Δ[α.sup.(5).sub.had]([M.sup.2.sub.Z]) = (274.9 ± 1.0) x [10.sup.-4]. The reduced electromagnetic coupling strength at [M.sub.Z] leads to an increase by 12 GeV in the central value of the Higgs boson mass obtained by the standard Gfitter fit to electroweak precision data.
Journal Article
Update of the ALEPH non-strange spectral functions from hadronic τ decays
by
Malaescu, B.
,
Yuan, C. Z.
,
Höcker, A.
in
Astronomy
,
Astrophysics and Cosmology
,
Elementary Particles
2014
An update of the ALEPH non-strange spectral functions from hadronic
τ
decays is presented. Compared to the 2005 ALEPH publication, the main improvement is related to the use of a new method to unfold the measured mass spectra from detector effects. This procedure also corrects a previous problem in the correlations between the unfolded mass bins. Results from QCD studies and for the evaluation of the hadronic vacuum polarisation contribution to the anomalous muon magnetic moment are derived using the new spectral functions. They are found in agreement with published results based on the previous set of spectral functions.
Journal Article
Update of the ALEPH non-strange spectral functions from hadronic tau decays
(ProQuest: ... denotes formulae and/or non-USASCII text omitted; see image) An update of the ALEPH non-strange spectral functions from hadronic ... decays is presented. Compared to the 2005 ALEPH publication, the main improvement is related to the use of a new method to unfold the measured mass spectra from detector effects. This procedure also corrects a previous problem in the correlations between the unfolded mass bins. Results from QCD studies and for the evaluation of the hadronic vacuum polarisation contribution to the anomalous muon magnetic moment are derived using the new spectral functions. They are found in agreement with published results based on the previous set of spectral functions.
Journal Article
The Euclidean Adler function and its interplay with ΔαQEDhad and αs
by
Malaescu, B.
,
Rodríguez-Sánchez, A.
,
Díaz-Calderón, D.
in
Approximation
,
Classical and Quantum Gravitation
,
Dispersion
2023
A
bstract
Three different approaches to precisely describe the Adler function in the Euclidean regime at around 2 GeVs are available: dispersion relations based on the hadronic production data in
e
+
e
−
annihilation, lattice simulations and perturbative QCD (pQCD). We make a comprehensive study of the perturbative approach, supplemented with the leading power corrections in the operator product expansion. All known contributions are included, with a careful assessment of uncertainties. The pQCD predictions are compared with the Adler functions extracted from
Δ
α
QED
had
(
Q
2
), using both the DHMZ compilation of
e
+
e
−
data and published lattice results. Taking as input the FLAG value of
α
s
, the pQCD Adler function turns out to be in good agreement with the lattice data, while the dispersive results lie systematically below them. Finally, we explore the sensitivity to
α
s
of the direct comparison between the data-driven, lattice and QCD Euclidean Adler functions. The precision with which the renormalisation group equation can be tested is also evaluated.
Journal Article
Evaluation of the strong coupling constant αS using the ATLAS inclusive jet cross-section data
2012
We perform a determination of the strong coupling constant using the latest ATLAS inclusive jet cross section data, from proton–proton collisions at
, and their full information on the bin-to-bin correlations. Several procedures for combining the statistical information from the different data inputs are studied and compared. The theoretical prediction is obtained using NLO QCD, and it also includes non-perturbative corrections. Our determination uses inputs with transverse momenta between 45 and 600 GeV, the running of the strong coupling being also tested in this range. Good agreement is observed when comparing our result with the world average at the Z-boson scale, as well as with the most recent results from the Tevatron.
Journal Article
Erratum to: A new evaluation of the hadronic vacuum polarisation contributions to the muon anomalous magnetic moment and to Formula omitted
2020
The original version of this article unfortunately contained a mistake.
Journal Article
Erratum to: A new evaluation of the hadronic vacuum polarisation contributions to the muon anomalous magnetic moment and to α(mZ2)
by
Malaescu, B.
,
Hoecker, A.
,
Zhang, Z.
in
Astronomy
,
Astrophysics and Cosmology
,
Elementary Particles
2020
The original version of this article unfortunately contained a mistake.
Journal Article
A new evaluation of the hadronic vacuum polarisation contributions to the muon anomalous magnetic moment and to Formula omitted
2020
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 [Formula omitted] 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 [Formula omitted] channel. For the muon [Formula omitted], we find for the lowest-order hadronic contribution [Formula omitted]. The full Standard Model prediction differs by [Formula omitted] from the experimental value. The five-quark hadronic contribution to [Formula omitted] is evaluated to be [Formula omitted].
Journal Article