Ψ-continuous functions and functions preserving ψ-density points

Linear Functions Preserving Multivariate and Directional Majorization

Let V and W be two real vector spaces and let &sim be a relation on both V and W. A linear function T : V → W is said to be a linear preserver (respectively strong linear preserver) of &sim if Tx &sim Ty whenever x &sim y (respectively Tx &sim Ty if and only if x &sim y). In this paper we characterize all linear functions T : M_{n,m} → M_{n,k} which preserve or strongly preserve multivariate an...

Resonances from J / Ψ and Ψ ′ Decays

The Institute of High Energy Physics at Beijing runs an electron-positron collider (BEPC) with a general purpose solenoidal detector, the Beijing Spectrometer (BES)[1], which is designed to study exclusive final states in ee annihilations at the center of mass energy from 3000 to 5600 MeV. In this energy range, the largest cross sections are at the J/Ψ(3097) and Ψ(3686) resonant peaks. At prese...

Ratio of Photoproduction Rates of J/ψ and ψ(2S)

There are different approaches for diffractive photoproduction of charmonia. Recently, a new approach is proposed, in which charm quarks are taken as heavy quarks and the nonperturbative effect related to charmonia can be handled with nonrelativistic QCD. The interaction between the cc̄ pair and the initial hadron is through exchange of soft gluons. The exchange of soft gluons can be studied wit...

J/ψ and Ψ Suppression in Hadronic Matter

We present a microscopic calculation of the breakup cross sections of J/ψ and ψ on pions and nucleons as a function of the kinetic energy. These cross sections are used for the investigation of the J/ψ to continuum and ψ/J/ψ ratios in ultrarelativistic heavy ion collisions. The contribution of produced comoving pions to the ψ/J/ψ signal is calculated. While this model can account for the data, ...

The c̄c purity of ψ ( 3770 ) and ψ ′ challenged