value of the parameter dependence on sphericity but not the shape. In summary, the sphericity distributions of several pa- rameters are found to be highly sensitive on the details of the gluon PDF. This opens an interesting possibility to compare the existing gluon PDFs with the experimen- tal results using a small sample of minimum bias data in pp collisions. The Pb Pb collisions, we are currently studying [11] in the same framework will benefit very much from the present analysis to determine the expected gluon saturation at low x$_{B}$ . Support for this work has been received in part by DGAPA-UNAM under PAPIIT grants IN115808 and IN116508 as well as by the HELEN program. Acknowledgments 4 [1] Pavel, M. Nodolsky, et. al., Phys. Rev. D 78 ,013004 (2008). [2] H-L. Lai, et. al., Parton Distribution for Event Genera- tors arXiv:0910.4183 [3] A. Ayala et. al., Eur.Phys.J. C62 535, (2009). A. Ortiz, G. Pai´ c, ALICE-INT-2009-015 (hep-ex/0912.0909). [4] A. Banfi et. al., JHEP 0408, 062 (2004). [5] W. K. Tung Perturbative QCD and the parton structure of the nucleon In *Shifman, M. (ed.): At the frontier of particle physics, Vol. 2, 887-971 (2001) . [6] T. Sj¨ ostrand, M. Bengtsson, Comput. Phys. Commun. 43 (1987) 367. [7] A. Morales, et. al., Eur.Phys.J.C , 50:435-466, (2007). [8] (ZEUS Collaboration), Eur.Phys.J.C , 42-1:1-16, (2005). [9] H. L. Lai et. al., Eur.Phys.J.C , 12-3:375-392, (2000). [10] J. F. Grosse-Oetringhaus and C. Ekman, ALICE-INT- 2007-005. [11] E. Cuautle, A. Ortiz, G. Pai´ c, work in progress