Measurement of the angular distribution of electrons from $W \to e \nu$ decays observed in $p\bar{p}$ collisions at $\sqrt{s} = 1.8$ TeV
Phys.Rev.D 63 (2001) 072001, 2001.
The collaboration

Abstract (data abstract)
FERMILAB-TEVATRON Collider. D0 Collaboration. First measurement of the ele ctron angular distribution parameter alpha_2 in W -& gt; e nu events as a function of W boson transverse momentum.