General formalism in collinear regime for pseudoscalar meson production in NN collisions

Pak, Namık Kemal
Rekalo, MP
The spin structure of the matrix element for the pseudoscalar meson production processes in nucleon-nucleon collisions is established in the collinear kinematical regime in terms of 3 independent scalar amplitudes. This result is valid for any reaction mechanism and for any energy of the colliding and the produced particles. The complete experiment for the full reconstruction of all 3 complex amplitudes must contain two different classes of polarization experiments. The polarization transfer coefficients can be used to determine the moduli of all 3 amplitudes, whereas the spin correlation coefficients for p + p collisions are sensitive to the relative phases of different amplitudes.


Extended dynamical symmetries of Landau levels in higher dimensions
Kürkcüoğlu, Seçkin; YURDUŞEN, İSMET (Springer Science and Business Media LLC, 2020-02-14)
Continuum models for time-reversal (TR) invariant topological insulators (Tis) in d >= 3 dimensions are provided by harmonic oscillators coupled to certain SO(d) gauge fields. These models are equivalent to the presence of spin-orbit (SO) interaction in the oscillator Hamiltonians at a critical coupling strength (equivalent to the harmonic oscillator frequency) and leads to flat Landau Level (LL) spectra and therefore to infinite degeneracy of either the positive or the negative helicity states depending on...
Principal-component analysis of two-particle azimuthal correlations in PbPb and pPb collisions at CMS
Sirunyan, A. M.; et. al. (2017-12-01)
For the first time a principle-component analysis is used to separate out different orthogonal modes of the two-particle correlation matrix from heavy ion collisions. The analysis uses data from root s(NN) = 2.76 TeV PbPb and root s(NN) = 5.02 TeV pPb collisions collected by the CMS experiment at the CERN Large Hadron Collider. Two-particle azimuthal correlations have been extensively used to study hydrodynamic flow in heavy ion collisions. Recently it was shown that the expected factorization of two-partic...
ThresholdJ/  production in nucleon-nucleon collisions
Rekalo, MP; Tomasi-Gustafsson, E (IOP Publishing, 2002-9-26)
We analyse J/psi-production in nucleon-nucleon collisions near threshold in the framework of a general model-independent formalism, which can be applied to any reaction N+N-->N+N+V-0, where V-0=omega, phi or J/psi. Such reactions show large isotopic effects: a large difference for pp and pn collisions, which is due to the different spin structure of the corresponding matrix elements. The analysis of the spin structure and of the polarization observables is based on symmetry properties of the strong interact...
Study of W boson production in pPb collisions at root(NN)-N-S=5.02 TeV
Adam, W.; et. al. (Elsevier BV, 2015-11-01)
The first study of W boson production in pPb collisions is presented, for bosons decaying to a muon or electron, and a neutrino. The measurements are based on a data sample corresponding to an integrated luminosity of 34.6 nb(-1) at a nucleon-nucleon centre-of-mass energy of root(NN)-N-S = 5.02 TeV, collected by the CMS experiment. The W boson differential cross sections, lepton charge asymmetry, and forward-backward asymmetries are measured for leptons of transverse momentum exceeding 25 GeV/c, and as a fu...
Investigations of spinodal dynamics in asymmetric nuclear matter within a stochastic relativistic model
Yılmaz, Osman; ACAR, FERİDE PINAR; Saatci, S.; GÖKALP, AHMET (Springer Science and Business Media LLC, 2013-03-01)
Early development of spinodal instabilities and density correlation functions in asymmetric nuclear matter are investigated in the stochastic extension of the Walecka-type relativistic mean field including coupling with rho meson. Calculations are performed under typical conditions encountered in heavy-ion collisions and in the crusts of neutron stars. In general, growth of instabilities occur relatively slower for increasing charge asymmetry of matter. At higher densities around rho = 0.4 rho(0) fluctuatio...
Citation Formats
N. K. Pak and M. Rekalo, “General formalism in collinear regime for pseudoscalar meson production in NN collisions,” EUROPEAN PHYSICAL JOURNAL A, pp. 121–124, 2001, Accessed: 00, 2020. [Online]. Available: