Polarization phenomena in vector meson photoproduction on nucleons near threshold

2000-10-21
Babacan, H
Babacan, T
Gokalp, A
Yılmaz, Osman
We propose and develop a model for rho (0) and omega photoproduction on nucleons near threshold based on t-, s-, and u-channel amplitudes. In t-channel we consider pi- and sigma- exchanges and we take the coupling constants (g(v), g(t)) in (s+u) nucleon contributions as free parameters. We fit our model to the available experimental differential cross-section data of gamma + p --> p + V reactions. We find that different models which are equivalently good for the description of the differential cross-section on proton targets may be differentiated by their predictions of the beam asymmetry on proton and neutron targets and of the differential cross-section on neutron targets.

Suggestions

Polarization phenomena in open charm photoproduction processes
Tomasi-Gustafsson, E; Rekalo, MP (American Physical Society (APS), 2004-05-01)
We analyze polarization effects in the associative photoproduction of pseudoscalar ((D) over bar (c)) charmed mesons in exclusive processes gamma+N-->Y-c+(D) over bar (c), Y-c=Lambda(c)(+), Sigma(c). Circularly polarized photons induce nonzero polarization of the Y-c hyperon with x and z components (in the reaction plane) and nonvanishing asymmetries A(x) and A(z) for polarized nucleon targets. These polarization observables can be predicted in a model-independent way for the exclusive (D) over bar (c)-prod...
A MODEL FOR TONAL CONTEXT TIME COURSE CALCULATION FROM ACOUSTICAL INPUT
IZMIRLI, O; BILGEN, S (Informa UK Limited, 1996-09-01)
This paper presents a two‐stage model that calculates tonal context as a continuous function in time. The model is capable of processing acoustical polyphonic inputs. The first stage is a simple note recogniser that produces pitch‐class note output corresponding to the acoustical input. A bank of leaky integrators constitute the second stage. The integration rates and saturation limits of these integrators vary with each musical event according to the relations among input notes and the candidates of tonal ...
Strong coupling constant of a negative parity nucleon with a pi meson in light-cone QCD sum rules
Alıyev, Tahmasıb; Savcı, Mustafa (2017-03-28)
We estimate the strong coupling constant between the negative parity nucleons with pi meson within the lightcone QCD sum rules. A method for eliminating the unwanted contributions coming from the nucleon-nucleon and nucleon-negative parity nucleon transition is presented. It is observed that the value of the strong coupling constant of the negative parity nucleon N* N* pi transition is smaller by about 50% compared to the coupling constant of the positive parity NN pi transition.
Polarized lepton pair forward-backward asymmetries in B -> K*l(+)l(-) decay beyond the standard model
Alıyev, Tahmasıb; Savcı, Mustafa (Springer Science and Business Media LLC, 2004-05-01)
We study the polarized lepton pair forward-backward asymmetries in B --> K*l+l(-) decay using a general, model independent form of the effective hamiltonian. We present the general expression for nine double-polarization forward-backward asymmetries. It is shown that, the study of the forward-backward asymmetries of the doubly-polarized lepton pair is a very useful tool for establishing new physics beyond the standard model.
Polarization anisotropy in nonpolar oriented GaN films studied by polarized photoreflectance spectroscopy
Behn, Udo; Misra, Pranob; Grahn, Holger T.; İmer, Muhsine Bilge; Nakamura, Shuji; DenBaars, Steven P.; Speck, James S. (Wiley, 2007-01-01)
We have used polarized photoreflectance spectroscopy to study the electronic-band-structure modification of GaN films grown along different nonpolar orientations due to biaxial, anisotropic in-plane strain. For nonpolar oriented films, the c-axis of GaN lies in the film plane. An unstrained, high-quality C-plane GaN film is used to estimate the difference in the band gap energies between 10 K and room temperature. We use the crystal-field and spin-orbit splitting energies and the deformation potential D, de...
Citation Formats
H. Babacan, T. Babacan, A. Gokalp, and O. Yılmaz, “Polarization phenomena in vector meson photoproduction on nucleons near threshold,” 2000, vol. 570, p. 551, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/62949.