https://doi.org/10.1140/epjc/s10052-020-08470-1
Regular Article – Theoretical Physics
Two-current correlations in the pion in the Nambu and Jona-Lasinio model
1
Instituto de Física, Universidad Nacional Autónoma de México, Apartado Postal 20-364, 01000, Ciudad de México, Mexico
2
Departamento de Física Teórica and IFIC, Centro Mixto Universidad de Valencia-CSIC, 46100, Burjassot, Valencia, Spain
3
Dipartimento di Fisica e Geologia, Università degli Studi di Perugia, and Istituto Nazionale di Fisica Nucleare Sezione di Perugia, Via A. Pascoli, 06123, Perugia, Italy
Received:
17
June
2020
Accepted:
12
September
2020
Published online:
1
October
2020
We present an analysis of two-current correlations for the pion in the Nambu–Jona-Lasinio model, with Pauli–Villars regularization. We provide explicit expressions in momentum space for two-current correlations corresponding to the zeroth component of the vector Dirac bilinear in the quark vertices, which has been evaluated on the lattice, thinking to applications in a high energy framework, as a step towards the calculation of pion double parton distributions. The numerical results show a remarkable qualitative agreement with recent lattice data. The factorization approximation into one-body currents is discussed based on previous evaluation of the relevant low energy matrix elements in the Nambu–Jona-Lasinio model, confirming the lattice result.
© The Author(s) 2020
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