arXiv subjects

K. P. Khemchandani

Publications and source records attributed to K. P. Khemchandani.

111 records · Page 7Linked to original sources

arXiv2003

Time delayed K+ N reactions and exotic baryon resonances

Evidences and hints, both from the theoretical and experimental side, of exotic baryon resonances with B=S, have been with us for the last thirty years. The poor status of the general acceptance of these Z* resonances is partly due to the prejudice against penta-quark baryons and partly due to the opinion that a proof of the existence of exotic states must be rigorous. This can refer to the quality and amount of data gathered, and also to the analytical methods applied in the study of these resonances. It seems then mandatory that all possibilities and aspects be exploited. We do that by analyzing the time delay in K+ N scattering, encountering clear signals of the exotic Z* resonances close to the pole values found in partial wave analyses.

hep-ph↗

arXiv2003

Collision times in pi-pi and pi-K scattering and spectroscopy of meson resonances

Using the concept of collision time (time delay) introduced by Eisenbud and Wigner and its connection to on-shell intermediate unstable states, we study mesonic resonances in pi-pi and pi-K scattering. The time-delay method proves its usefulness by revealing the spectrum of the well-known rho- and K*-mesons and by supporting some speculations on rho-mesons in the 1200 MeV region. We use this method further to shed some light on more speculative meson resonances, among others the enigmatic scalars. We confirm the existence of chiralons below 1 GeV in the unflavoured and strange meson sector.

hep-ph↗

arXiv2002

Study of the $η$-nucleus interaction in the $p d \to ^3He η$ reaction near threshold

A detailed study of the effect of the $η$-nucleus final state interaction (FSI) in the $p d \to ^3$He$ η$ reaction close to threshold is presented. The FSI is incorporated through a T-matrix for $η^3$He elastic scattering, constructed using few body equations. This T-matrix accounts for off-shell and binding effects in $η$-nucleus scattering. The energy dependence of the data on the $p d \to ^3$He$ η$ reaction near threshold is reproduced only after including the FSI. The off-shell and binding effects in $η^3$He scattering are found to be important. Given the uncertainty in the knowledge of the elementary $η$-nucleon interaction, the sensitivity of the $ p d \to ^3$He$ η$ cross section to different prescriptions of the elementary t-matrix, $t_{ηN \to ηN}$ is also discussed.

nucl-th↗