A Dual Parton Model with a formation zone intranuclear cascade in the spectators of the projectile and target nuclei is studied. The hadrons produced in the formation zone cascade contribute to Feynman–xF and lab–x distributions in the fragmentation regions of the target and projectile nuclei. We discuss the consequences of this model in the secondary cosmic ray production, by analyzing the cal...

A Dual Parton Model with a formation zone intranuclear cascade in the spectators of the projectile and target nuclei is studied. The hadrons produced in the formation zone cascade contribute to Feynman–xF and lab–x distributions in the fragmentation regions of the target and projectile nuclei. We discuss the consequences of this model in the secondary cosmic ray production by analyzing the calc...

Strong, anisotropic turbulence reflecting magnetized filaments is considered, to model the diffusive acceleration of particles by shock waves in active galactic nucleus jets. We address that at knot A of the nearby M87 jet, the shock involving the filamentary turbulence can accelerate an iron nucleus to zetta-eV (ZeV; 10 eV) ranges. A smaller value of the particle diffusion coefficient is found...

The unexpected discovery of the cosmic microwave background by Arno Penzias and Robert Wilson in 1965 is now the centerpiece of our understanding of the Big Bang and the subsequent evolution of the universe. (See PHYSICS TODAY, November 1997, page 32.) The discovery also set off something of a race to verify one of its implications for cosmic rays. In 1966, Kenneth Greisen (Cornell University) ...

We discuss an effective numerical method for solving the transport equations for cosmic ray nucleons in the atmosphere. It is demonstrated that the nucleon attenuation lengths are strongly energy and depth dependent due to the non-power-law behavior of the primary spectrum, growth of the total inelastic cross sections with energy, and scaling violation in the nucleon-nucleus interactions. The n...

Via its role in aerosol formation, cosmic ray may affect the global cloudiness and hence climate. Here we show that an increase in cosmic ray fluxes may lead to an increase in particle production in the lower troposphere but a decrease in particle production in the upper troposphere. In addition to the reported positive correlation between cosmic ray variations and low cloudiness, our analysis ...

We discuss collective effects like percolation, quark gluon plasma, or string fusion and their effect on the longitudinal development of high energy showers in air. It is shown that iron–air showers could develop more slowly than expected and produce the observed change in the slope of X max at the highest energies. It is expected that the Relativistic Heavy Ion Collider (RHIC) and the Large Ha...