We perform a re-analysis of Belle data for the transverse lambda and <(lambda)over bar > polarization in e(+)e(-) annihilation processes within a transverse momentum dependent (TMD) factorization approach. We consider two data sets, one referring to the associated production of lambda's with a light unpolarized hadron in an almost back-to-back configuration, and one for the inclusive lambda production, with the reconstruction of the thrust axis. We adopt the Collins-Soper-Sterman framework and employ the recent formulation on the factorization of single-inclusive hadron production. This extends a previous phenomenological study carried out in a more simplified TMD approach, leading to a new extraction of the polarizing fragmentation function (FF). While confirming several features of the previous analysis, here we include the proper QCD scale dependence of this TMD FF and carefully exploit the role of its nonperturbative component. The compatibility, within a unique TMD factorization scheme, of double and single-inclusive hadron production is discussed in detail. Moreover, we consider another data set for inclusive A production, at much larger energies, from the OPAL Collaboration, in order to test the consistency of the entire approach. Finally, we elaborate on some fundamental issues like the role of SU(2) isospin symmetry and the heavy quark contributions.
Transverse Lambda polarization in e+e- processes within a TMD factorization approach and the polarizing fragmentation function
Umberto D'Alesio
;Francesco Murgia;Marco Zaccheddu
2022-01-01
Abstract
We perform a re-analysis of Belle data for the transverse lambda and <(lambda)over bar > polarization in e(+)e(-) annihilation processes within a transverse momentum dependent (TMD) factorization approach. We consider two data sets, one referring to the associated production of lambda's with a light unpolarized hadron in an almost back-to-back configuration, and one for the inclusive lambda production, with the reconstruction of the thrust axis. We adopt the Collins-Soper-Sterman framework and employ the recent formulation on the factorization of single-inclusive hadron production. This extends a previous phenomenological study carried out in a more simplified TMD approach, leading to a new extraction of the polarizing fragmentation function (FF). While confirming several features of the previous analysis, here we include the proper QCD scale dependence of this TMD FF and carefully exploit the role of its nonperturbative component. The compatibility, within a unique TMD factorization scheme, of double and single-inclusive hadron production is discussed in detail. Moreover, we consider another data set for inclusive A production, at much larger energies, from the OPAL Collaboration, in order to test the consistency of the entire approach. Finally, we elaborate on some fundamental issues like the role of SU(2) isospin symmetry and the heavy quark contributions.File | Dimensione | Formato | |
---|---|---|---|
PT Lambda CSS JHEP 12 2022 074.pdf
accesso aperto
Descrizione: articolo
Tipologia:
versione editoriale (VoR)
Dimensione
879.06 kB
Formato
Adobe PDF
|
879.06 kB | Adobe PDF | Visualizza/Apri |
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.