Rapidity long range correlations, parton percolation and color glass condensate

The similarities between string percolation and Glasma results are emphasized, special attention being paid to rapidity long range correlations, ridge structure and elliptic flow. As the string density of high multiplicity pp collisions at LHC energies has similar value as the corresponding to Au-Au semi-central collisions at RHIC we also expect in pp collisions long rapidity correlations and ridge structure, extended more than 8 units in rapidity.Comment: 3 pages, 3 figures, conference Quark Confinement and the hadron spectrum I

Atomic Bremsstrahlung: retrospectives, current status and perspectives

We describe here the Atomic bremsstrahlung - emission of continuous spectrum electromagnetic radiation, which is generated in collisions of particles that have internal deformable structure that includes positively and negatively charged constituents. The deformation of one of or both colliding partners induces multiple, mainly dipole, time-dependent electrical moments that become a source of radiation. The history of Atomic bremsstrahlung invention is presented and it's unusual in comparison to ordinary bremsstrahlung properties are discussed. As examples, fast electron - atom, non-relativistic and relativistic collisions are considered. Attention is given to ion - atom and atom - atom collisions. Specifics of elastic and inelastic (i.e. radiation accompanied by destruction of collision partners) Atomic bremsstrahlung will be mentioned. Attention will be given to possible manifestation of Atomic bremsstrahlung in Nature and in some exotic systems, for instance scattering of electrons upon muonic hydrogen. Some cooperative effects connected to Atomic bremsstrahlung will be considered. New classical schemes similar to Atomic bremsstrahlung will be presented.Comment: 29 pages, 11 figures Submitted to Electron spectroscopy and the related phenomen

A possible probe of the new fifth force

The proposed protophobic fifth force in \emph{Phys. Rev. Lett. {\bf \emph{117}}, 071803 (2016)} recently attracts much attention. To confirm or refute the existence of this new interaction, here I propose a method to probe the protophobic fifth force in dense matter that formed in nucleus-nucleus collisions. As expected, the protophobic fifth force has negligible effects on the usual observables in nucleus-nucleus collisions. While the protophobic fifth force evidently affects the value of final positively and negatively charged pions ratio at very high kinetic energies. The signal thus could be used to probe the protophobic fifth force in dense matter by nucleus-nucleus collisions' experiments at current experimental equipments worldwide.Comment: 5 pages, 3 figure

J/\psi\ and \psi' production in proton(deuteron)-nucleus collisions: lessons from RHIC for the proton-lead LHC run

We study the impact of different cold nuclear matter effects both on J/\psi\ and \psi' production, among them the modification of the gluon distribution in bound nucleons, commonly known as gluon shadowing, and the survival probability for a bound state to escape the nucleus --the nuclear absorption. Less conventional effects such as saturation and fractional energy loss are also discussed. We pay a particular attention to the recent PHENIX preliminary data on \psi' production in dAu collisions at sqrt{s}=200 GeV, which show a strong suppression for central collisions, 5 times larger than the one obtained for J/\psi\ production at the same energy. We conclude that none of the abovementioned mechanisms can explain this experimental result.Comment: 4 pages, 2 tables, 2 figures, contribution to Rencontres du Vietnam, 'Heavy Ion Collisions in the LHC Era', 15-21 July 2012, Quy Nhon, Vietna

Hypermatter : properties and formation in relativistic nuclear collisions

The extension of the Periodic System into hitherto unexplored domains - anti- matter and hypermatter - is discussed. Starting from an analysis of hyperon and single hypernuclear properties we investigate the structure of multi-hyperon objects (MEMOs) using an extended relativistic meson field theory. These are contrasted with multi-strange quark states (strangelets). Their production mechanism is stud- ied for relativistic collisions of heavy ions from present day experiments at AGS and SPS to future opportunities at RHIC and LHC. It is pointed out that abso- lutely stable hypermatter is unlikely to be produced in heavy ion collisions. New attention should be focused on short lived metastable hyperclusters ( / 10 10s) and on intensity interferometry of multi-strange-baryon correlations