Speaker
Prof.
Barbara Badelek
(University of Warsaw, Poland)
Description
A description of a nucleon structure in terms of partons demands
knowledge of parton momentum-, helicity- and transversity
distribution functions. COMPASS facility at CERN, with its high energy,
polarised muon beam, large polarised proton- and deuteron targets
and particle identification detectors, permits investigating the
(longitudinal and transverse) spin-dependent structure function
and unfolding relevant parton distribution functions.
An overview of the following COMPASS results will be given:
all the inclusive data for the proton and deuteron spin dependent
structure function $g_1$ and their NLO QCD analysis (for a part of them),
the LO analysis of flavour helicity distributions based on the
semi-inclusive data with identified hadrons and with a particular
attention drawn to the problem of a strange sea polarisation
determination and to different methods of extracting the
(LO and NLO) polarisation of gluons. Ongoing analysis
of single and double hadron multiplicities produced on
the deuteron target which may lead to a determination
of fragmentation functions, critical for the extraction
of the strange sea polarisation will also be mentioned.
Author
Prof.
Barbara Badelek
(University of Warsaw, Poland)
