Determination of {pi}{sup 0} meson quadrupole polarizabilities from the process {gamma}{gamma}{yields}{pi}{sup 0}{pi}{sup 0}
- P.N. Lebedev Physical Institute, Leninsky Prospect 53, Moscow RU-119991 (Russian Federation)
A fit of the experimental data to the total cross section of the process {gamma}{gamma}{yields}{pi}{sup 0}{pi}{sup 0} in the energy region from 270 to 2250 MeV has been carried out using dispersion relations for the invariant amplitudes where the quadrupole polarizabilities are free parameters. As a result the sum and difference of the electric and magnetic quadrupole polarizabilities of the {pi}{sup 0} meson have been found for the first time: ({alpha}{sub 2}+{beta}{sub 2}){sub {pi}{sup 0}}=(-0.181{+-}0.004)x10{sup -4} fm{sup 5}, ({alpha}{sub 2}-{beta}{sub 2}){sub {pi}{sup 0}}=(39.70{+-}0.02)x10{sup -4} fm{sup 5}. In addition, dispersion sum rules have been constructed for this sum and difference, respectively. The values of ({alpha}{sub 2}-{beta}{sub 2}){sub {pi}{sup 0}} and ({alpha}{sub 2}+{beta}{sub 2}){sub {pi}{sup 0}} extracted from the experimental data on the process {gamma}{gamma}{yields}{pi}{sup 0}{pi}{sup 0} are in good agreement with the result of calculations in the framework of these dispersion sum rules.
- OSTI ID:
- 20699014
- Journal Information:
- Physical Review. C, Nuclear Physics, Journal Name: Physical Review. C, Nuclear Physics Journal Issue: 3 Vol. 72; ISSN 0556-2813; ISSN PRVCAN
- Country of Publication:
- United States
- Language:
- English
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