J/ψproduction at photon-photon colliders as a probe of the color octet mechanism

Abstract

We study J/ production at photon-photon colliders, which can be realized with Compton scattering of laser photons at e ϩ e Ϫ colliders. We find that the production rate through the color-octet channel is comparable to that through the color-singlet channel. Experimentally the two mechanisms can be studied separately because the processes have different signals. ͓S0556-2821͑98͒04301-X͔

Associated production of heavy quarkonia and electroweak bosons at present and future colliders

“…To our knowledge, the formulas presented in the Appendix cannot be found elsewhere in the literature. However, the literature contains analytic results for the partonic subprocesses pertinent to the case of C = J/ψ and D = γ, namely, for processes (11) [10,11,12], (12) [14], and (13) [14,16] with ς = 3 S 1 , and for processes (14) and (15) with ς = 1 S 0 , 3 S 1 , 3 P J [14,16]. We agree with them, except for Eq.…”

DoubleJ/ψproduction at photon colliders

“…Considering there are remaining disagreements among three independent calculations on the leading order processes (1) and (2) [9][10][11], we have done a check over them and find an agreement with refs. [9] and [11] on the expression for octet process, i.e., the eq. (7) of ref.…”

Theory of hard photoproduction

“…Transverse momentum (top) and pseudorapidity (bottom) dependence of the massive (Frixione, Krä mer, and Laenen, 2000a) and a massless Kramer, 1996b, 1998a) next-to-leading-order D* photonphoton cross section compared to OPAL data (Abbiendi et al, 2001a). same order v 4 relative to ͗O 1 J/⌿ ( 3 S 1 )͘, the operator matrix elements ͗O 8 J/⌿ ( 1 S 0 )͘ and ͗O 8 J/⌿ ( 3 P J )͘ with J ϭ0,1,2 contribute in photon-and gluon-quark scattering with final-state quarks and in quark-antiquark annihilation with final-state gluons (Japaridze and Tkabladze, 1998;Ma, McKellar, and Paranavitane, 1998;Klasen, Kniehl, Mihaila, and Steinhauser, 2001a;Godbole, Indumathi, and Krä mer, 2002).…”