Constraining the low-energy pion electromagnetic form factor with spacelike data
نویسندگان
چکیده
منابع مشابه
Constraining the low-energy pion electromagnetic form factor with spacelike data
The pionic contribution to the g−2 of the muon involves a certain integral over the modulus squared of Fπ(t), the electromagnetic form factor of the pion. We extend techniques that use cut-plane analyticity properties of Fπ(t) in order to account for present day estimates of the pionic contribution and experimental information at a finite number of points in the spacelike region. Using data fro...
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The Taylor coefficients c and d of the Pion EM form factor are constrained using analyticity, knowledge of the phase of the form factor in the time-like region, 4m 2 π ≤ t ≤ tin and its value at one space-like point, using as input the (g − 2) of the muon. This is achieved using the technique of Lagrange multipli-ers, that gives a transparent expression for the corresponding bounds. We present ...
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ژورنال
عنوان ژورنال: The European Physical Journal C
سال: 2008
ISSN: 1434-6044,1434-6052
DOI: 10.1140/epjc/s10052-008-0533-6