Sea quark and gluon contents of light mesons at low Q(2) scale

摘要

We investigate the contributions of sea quarks and gluon to the structure of pion and kaon at low Q(2) scale. To this end, we calculate the sea quark and gluon distribution functions of these mesons applying the modified chiral quark model (chi QM). We also compute the total momentum fraction which is carried by sea quarks and gluon in pi(+) and K+ mesons. It is found that sea quarks and gluon carry about 30% of total momentum of the light mesons at Q(2) = 0.25 GeV2. Furthermore, it is shown that the gluon contents of pion and kaon are different. On the other hand, we obtain the quark- anti quark asymmetry of the strange sea and down sea in pi(+) and K+, respectively. These asymmetries are determined based on the modified chi QM due to the chiral symmetry breaking.