Publicação
Leading and Next-to-Leading Order Gluon Polarization in the Nucleon and Longitudinal Double Spin Asymmetries from Open Charm Muoproduction
| dc.contributor.author | COMPASS collaboration (221 authors) | |
| dc.contributor.author | Bordalo, P. | |
| dc.contributor.author | Franco, C. | |
| dc.contributor.author | Nunes, A.S. | |
| dc.contributor.author | Quaresma, M. | |
| dc.contributor.author | Quintans, C. | |
| dc.contributor.author | Ramos, S. | |
| dc.contributor.author | Silva, L. | |
| dc.contributor.author | Stolarski, M. | |
| dc.date.accessioned | 2019-02-03T21:56:01Z | |
| dc.date.available | 2019-02-03T21:56:01Z | |
| dc.date.issued | 2013-03-25 | |
| dc.date.updated | 2019-02-03T21:56:01Z | |
| dc.description.abstract | The gluon polarisation in the nucleon was measured using open charm production by scattering 160 GeV/c polarised muons off longitudinally polarised protons or deuterons. The data were taken by the COMPASS collaboration between 2002 and 2007. A detailed account is given of the analysis method that includes the application of neural networks. Several decay channels of D^0 mesons are investigated. Longitudinal spin asymmetries of the D meson production cross-sections are extracted in bins of D^0 transverse momentum and energy. At leading order QCD accuracy the average gluon polarisation is determined as (Delta g/G)^LO=-0.06 +/- 0.21 (stat.) +/- 0.08 (syst.) at the scale <mu^2> ~13 (GeV/c)^2 and an average gluon momentum fraction <x>~ 0.11. For the first time, the average gluon polarisation is also obtained at next-to-leading order QCD accuracy as (Delta g/G)^NLO = -0.13 +/- 0.15 (stat.) +/- 0.15 (syst.) at the scale <mu^2> ~ 13 (\GeV/c)^2 and <x> ~ 0.20. | |
| dc.description.version | Peer Reviewed | |
| dc.identifier | Phys.Rev. D87 (2013) 052018; DOI 10.1103/PhysRevD.87.052018 | |
| dc.identifier.uri | http://dx.doi.org/10.1103/PhysRevD.87.052018 | |
| dc.identifier.uri | http://hdl.handle.net/10400.26/26336 | |
| dc.language.iso | eng | |
| dc.title | Leading and Next-to-Leading Order Gluon Polarization in the Nucleon and Longitudinal Double Spin Asymmetries from Open Charm Muoproduction | |
| dc.type | journal article | |
| dspace.entity.type | Publication | |
| rcaap.rights | openAccess | pt |
| rcaap.type | article |