Linearly polarized Gluons and the Higgs Transverse Momentum Distribution
  We investigate the possible role of linearly polarized gluons in Higgs production from unpolarized pp collisions. The transverse momentum distribution of the produced Higgs boson is found to exhibit a modulation with respect to the naive, unpolarized expectation, with the sign depending on the parity of the Higgs boson. The transverse momentum distribution of a scalar Higgs will, therefore, have a shape clearly different from a pseudoscalar Higgs. We suggest that this effect can be used to determine the parity of the Higgs at the LHC, without the need to use challenging angular distributions. 
Wilco J. den Dunnen, Daniel Boer, Cristian Pisano, Marc Schlegel and   Werner Vogelsang
hep-ph