Download or read book Two Photon Production of Charm States - a Charmonium Calculation written by and published by . This book was released on 1980 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The comparison of the nonrelativistic multichannel calculation with the double Rutherford process shows that duality is satisfied, in the sense that if one averages the actual cross sections for a wide enough range of W one gets the same result as for nonstrongly interacting point like quarks. It has been shown for the case of ee− annihilation that duality in this sense follows from nonrelativistic potential models; and it has been verified that this proof can be extended to two-photon processes.