Pion charge radius from pion+electron elastic scattering data

GeV² using a method based on interpolation via continued fractions augmented by statistical sampling. The scheme avoids any assumptions on the form of function used for the representation of data and subsequent extrapolation onto

Q^{2} ≃ 0

. Combining results obtained from the two available data sets, we obtain

r_{π} = 0.640 (7)

fm, a value

2.4 σ

below today's commonly quoted average. The tension may be relieved by collection and similar analysis of new precise data that densely cover a domain which reaches well below

Q^{2} = 0.015

GeV². Considering available kaon+electron elastic scattering data sets, our analysis reveals that they contain insufficient information to extract an objective result for the charged-kaon radius,

r_{K}

. New data with much improved precision, low-

Q^{2}

reach and coverage are necessary before a sound result for

r_{K}

can be recorded.

Note:

5 pages, 4 figures

Electric charge radius
Emergence of mass
Lepton-hadron scattering
Nambu-Goldstone bosons
Pions and kaons
Strong interactions in the standard model of particle physics
electric charge radius
emergence of mass
lepton-hadron scattering
Nambu-Goldstone boson

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