Electromagnetic charge radius of the pion at high precision - INSPIRE

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Electromagnetic charge radius of the pion at high precision

Jun 13, 2017

5 pages

Published in:

Phys.Rev.Lett. 119 (2017) 13, 132002

Published: Sep 28, 2017

e-Print:

1706.04020 [hep-ph]

DOI:

10.1103/PhysRevLett.119.132002

PDG:

{{\mathit \pi}^{\pm}}

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Abstract: (APS)

We present a determination of the pion charge radius from high precision data on the pion vector form factor from both timelike and spacelike regions, using a novel formalism based on analyticity and unitarity. At low energies, instead of the poorly known modulus of the form factor, we use its phase, known with high accuracy from Roy equations for ππ elastic scattering via the Fermi-Watson theorem. We use also the values of the modulus at several higher timelike energies, where the data from e+e- annihilation and τ decay are mutually consistent, as well as the most recent measurements at spacelike momenta. The experimental uncertainties are implemented by Monte Carlo simulations. The results, which do not rely on a specific parametrization, are optimal for the given input information and do not depend on the unknown phase of the form factor above the first inelastic threshold. Our prediction for the charge radius of the pion is rπ=(0.657±0.003) fm, which amounts to an increase in precision by a factor of about 2.7 compared to the Particle Data Group average.

Note:

6 pages, 2 figures, typos corrected, citations added, version accepted for publication in Physical Review Letters

elastic scattering
pi: charge radius
form factor: vector
analytic properties
unitarity
BES
BaBar
BELLE
CLEO
KLOE

References(34)

Figures(4)

[1]

Review of Particle Physics

C. Patrignani
(
- Bologna U. and
- INFN, Bologna
)
,
K. Agashe
(
- Maryland U.
)
,
G. Aielli
(
- U. Rome 2, Tor Vergata (main)
)
,
C. Amsler
(
- U. Bern, AEC and
- Stefan Meyer Inst. Subatomare Phys.
)
,
M. Antonelli
(
- Frascati
)

et al.

- Chin.Phys.C 40 (2016) 10, 100001
•
DOI:
- 10.1088/1674-1137/40/10/100001

[2]

The Vector and scalar form-factors of the pion to two loops

J. Bijnens
(
- Lund U., Dept. Theor. Phys.
)
,
G. Colangelo
(
- Frascati
)
,
P. Talavera
(
- Barcelona, Polytechnic U.
)

- JHEP 05 (1998) 014
•
e-Print:
- hep-ph/9805389
•
DOI:
- 10.1088/1126-6708/1998/05/014

[3]

Review of lattice results concerning low-energy particle physics

S. Aoki
(
- Kyoto U., Yukawa Inst., Kyoto
)
,
Y. Aoki
(
- KMI, Nagoya and
- RIKEN BNL
)
,
D. Becirevic
(
- Orsay, LPT
)
,
C. Bernard
(
- Washington U., St. Louis
)
,
T. Blum
(
- Connecticut U. and
- RIKEN BNL
)

et al.

- Eur.Phys.J.C 77 (2017) 2, 112
•
e-Print:
- 1607.00299
•
DOI:
- 10.1140/epjc/s10052-016-4509-7

[4]

Lectures on pions and nucleons

E. Fermi
,
B.T. Feld

- Nuovo Cim. 2 (1955) 1suppl, 17-95
•
DOI:
- 10.1007/BF02746078

[4]

Lectures on pions and nucleons

E. Fermi
(
- Unlisted
)

- Riv.Nuovo Cim. 31 (2008) 1, 1-73
•
DOI:
- 10.1393/ncr/i2008-10028-x

[5]

Some general relations between the photoproduction and scattering of pi mesons

Kenneth M. Watson
(
- Wisconsin U., Madison
)

- Phys.Rev. 95 (1954) 228-236
•
DOI:
- 10.1103/PhysRev.95.228

[6]

The Hadronic contributions to the anomalous magnetic moment of the muon

- Phys.Rev.D 71 (2005) 073008
•
e-Print:
- hep-ph/0402285
•
DOI:
- 10.1103/PhysRevD.71.073008

[7]

The branching ratio $\omega \rightarrow \pi ^+\pi ^-$ revisited

C. Hanhart
(
- IAS, Julich and
- Julich, Forschungszentrum
)
,
S. Holz
(
- Bonn U., HISKP
)
,
B. Kubis
(
- Bonn U., HISKP and
- Bonn U.
)
,
A. Kupść
(
- Uppsala U. and
- Warsaw, Inst. Nucl. Studies and
- Warsaw U.
)
,
A. Wirzba
(
- IAS, Julich and
- Julich, Forschungszentrum and
- Santa Barbara, KITP
)

et al.

- Eur.Phys.J.C 77 (2017) 2, 98,
- Eur.Phys.J.C 78 (2018) 6, 450 (erratum)
•
e-Print:
- 1611.09359
•
DOI:
- 10.1140/epjc/s10052-017-4651-x

[8]

Dispersive and chiral symmetry constraints on the light meson form-factors

Irinel Caprini
(
- Bucharest, IFIN-HH
)

- Eur.Phys.J.C 13 (2000) 471-484
•
e-Print:
- hep-ph/9907227
•
DOI:
- 10.1007/s100520050710

[9]

Theory of unitarity bounds and low energy form factors

- Eur.Phys.J.A 45 (2010) 389-399
•
e-Print:
- 1004.4257
•
DOI:
- 10.1140/epja/i2010-11010-5

[10]

Parametrisation-free determination of the shape parameters for the pion electromagnetic form factor

B. Ananthanarayan
(
- Bangalore, Indian Inst. Sci.
)
,
I. Caprini
(
- Bucharest, IFIN-HH
)
,
Diganta Das
(
- IMSc, Chennai
)
,
I. Sentitemsu Imsong
(
- Siegen U.
)

- Eur.Phys.J.C 73 (2013) 2520
•
e-Print:
- 1302.6373
•
DOI:
- 10.1140/epjc/s10052-013-2520-9

[11]

Precise determination of the low-energy hadronic contribution to the muon $g-2$ from analyticity and unitarity: An improved analysis

- Phys.Rev.D 93 (2016) 11, 116007
•
e-Print:
- 1605.00202
•
DOI:
- 10.1103/PhysRevD.93.116007

[12]

Pion form-factor phase, pi pi elasticity and new e+ e- data

- Phys.Lett.B 582 (2004) 27-31
•
e-Print:
- hep-ph/0311366
•
DOI:
- 10.1016/j.physletb.2003.12.030

[13]

Roy equation analysis of pi pi scattering

B. Ananthanarayan
(
- Bangalore, Indian Inst. Sci.
)
,
G. Colangelo
(
- Zurich U.
)
,
J. Gasser
(
- Bern U.
)
,
H. Leutwyler
(
- Bern U.
)

- Phys.Rept. 353 (2001) 207-279
•
e-Print:
- hep-ph/0005297
•
DOI:
- 10.1016/S0370-1573(01)00009-6

[14]

Regge analysis of the pi pi scattering amplitude

- Eur.Phys.J.C 72 (2012) 1860
•
e-Print:
- 1111.7160
•
DOI:
- 10.1140/epjc/s10052-012-1860-1

[15]

The Pion-pion scattering amplitude. IV: Improved analysis with once subtracted Roy-like equations up to 1100 MeV

- Phys.Rev.D 83 (2011) 074004
•
e-Print:
- 1102.2183
•
DOI:
- 10.1103/PhysRevD.83.074004

[16]

Precise measurement of the e+ e- ---> pi+ pi- (gamma) cross section with the Initial State Radiation method at BABAR

BaBar

Collaboration

•

Bernard Aubert
(
- Annecy, LAPP
)

et al.

- Phys.Rev.Lett. 103 (2009) 231801
•
e-Print:
- 0908.3589
•
DOI:
- 10.1103/PhysRevLett.103.231801

[17]

The Pion Form-Factor

- Phys.Rev.Lett. 43 (1979) 246
•
DOI:
- 10.1103/PhysRevLett.43.246

[18]

Exclusive Processes in Quantum Chromodynamics: Evolution Equations for Hadronic Wave Functions and the Form-Factors of Mesons

G.Peter Lepage
(
- Cornell U., LNS
)
,
Stanley J. Brodsky
(
- SLAC
)

- Phys.Lett.B 87 (1979) 359-365
•
DOI:
- 10.1016/0370-2693(79)90554-9

[19]

Complete next-to-leading order perturbative QCD prediction for the pion form-factor

- Phys.Rev.D 60 (1999) 074004
•
e-Print:
- hep-ph/9802204
•
DOI:
- 10.1103/PhysRevD.60.074004

[20]

High-statistics measurement of the pion form factor in the rho-meson energy range with the CMD-2 detector

CMD-2

Collaboration

•

R.R. Akhmetshin

et al.

- Phys.Lett.B 648 (2007) 28-38
•
e-Print:
- hep-ex/0610021
•
DOI:
- 10.1016/j.physletb.2007.01.073

[21]

Update of the e+ e- ---> pi+ pi- cross-section measured by SND detector in the energy region 400-MeV < s**(1/2) < file1000-MeV

M.N. Achasov
(
- Novosibirsk, IYF and
- Novosibirsk State U.
)
,
K.I. Beloborodov
(
- Novosibirsk, IYF and
- Novosibirsk State U.
)
,
A.V. Berdyugin
(
- Novosibirsk, IYF and
- Novosibirsk State U.
)
,
A.G. Bogdanchikov
(
- Novosibirsk, IYF and
- Novosibirsk State U.
)
,
A.V. Bozhenok
(
- Novosibirsk, IYF and
- Novosibirsk State U.
)

et al.

- J.Exp.Theor.Phys. 103 (2006) 380-384,
- Zh.Eksp.Teor.Fiz. 130 (2006) 437-441
•
e-Print:
- hep-ex/0605013
•
DOI:
- 10.1134/S106377610609007X

[21]

Update of the e+ e- ---> pi+ pi- cross-section measured by SND detector in the energy region 400-MeV < s**(1/2) < file1000-MeV

M.N. Achasov
(
- Novosibirsk, IYF and
- Novosibirsk State U.
)
,
K.I. Beloborodov
(
- Novosibirsk, IYF and
- Novosibirsk State U.
)
,
A.V. Berdyugin
(
- Novosibirsk, IYF and
- Novosibirsk State U.
)
,
A.G. Bogdanchikov
(
- Novosibirsk, IYF and
- Novosibirsk State U.
)
,
A.V. Bozhenok
(
- Novosibirsk, IYF and
- Novosibirsk State U.
)

et al.

- J.Exp.Theor.Phys. 103 (2006) 380-384,
- Zh.Eksp.Teor.Fiz. 130 (2006) 437-441
•
e-Print:
- hep-ex/0605013
•
DOI:
- 10.1134/S106377610609007X

[22]

Precise Measurement of the $e^+ e^- \to \pi^+\pi^- (\gamma)$ Cross Section with the Initial-State Radiation Method at BABAR

BaBar

Collaboration

•

J.P. Lees
(
- Annecy, LAPP
)

et al.

- Phys.Rev.D 86 (2012) 032013
•
e-Print:
- 1205.2228
•
DOI:
- 10.1103/PhysRevD.86.032013

[23]

Measurement of $\sigma(e^+ e^- \to \pi^+ \pi^-)$ from threshold to 0.85 GeV $^2$ using Initial State Radiation with the KLOE detector

KLOE

Collaboration

•

F. Ambrosino
(
- Naples U. and
- INFN, Naples
)

et al.

- Phys.Lett.B 700 (2011) 102-110
•
e-Print:
- 1006.5313
•
DOI:
- 10.1016/j.physletb.2011.04.055

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