New Anomalous Exchange in Regge Phenomenology and Hard Diffraction
  A new mechanism for hard diffraction based on the anomalous $f_1$ trajectory exchange, which we identify as the odd signature partner of the Pomeron, is suggested. We calculate the contribution of the $f_1$ exchange to elastic and dissociative electromagnetic production of vector mesons and show that it gives a dominant contribution to the differential cross sections at large momentum transfers. 
N.I. Kochelev, D.-P. Min, Y. Oh, V.Vento, A.V. Vinnikov