A study of gamma-families generated in nucleon-nucleus (NA) and pion-nucleus (pi A) interactions

The separation of the gamma families generated in nucleon-nuclear and pion-nuclear (PI-A) interactions is realized from the analysis of simulated gamma families. Some characteristics of NA and PI families and the influence of the process of inelastic charge-exchange of charged pions neutral ones type of PI + or - A yields are studied

A comparative analysis of gamma and hadron families at the superhigh energies recorded in experiment Pamir

A comparative analysis of hadron and gamma families which have undergone the decascading procedure is made. Results are compared with different models of interactions. In hadron families with energies Summary E sub H sup gamma 20 TeV as well as in gamma families with energies Summary E sub gamma 70 TeV, increasing azimuthal anisotropy is observed

Light Baryon Resonances: Restrictions and Perspectives

The problem of nucleon resonances N' with masses below the Delta is considered. We derive bounds for the properties of such states. Some of these are new, while others improve upon existing limits. We discuss the nature of N' states, and their unitary partners, assuming their existence can be verified.Comment: 11 pages, 11 figur

Low energy neutrino scattering measurements at future Spallation Source facilities

In the future several Spallation Source facilities will be available worldwide. Spallation Sources produce large amount of neutrinos from decay-at-rest muons and thus can be well adapted to accommodate state-of-the-art neutrino experiments. In this paper low energy neutrino scattering experiments that can be performed at such facilities are reviewed. Estimation of expected event rates are given for several nuclei, electrons and protons at a detector located close to the source. A neutrino program at Spallation Sources comprises neutrino-nucleus cross section measurements relevant for neutrino and core-collapse supernova physics, electroweak tests and lepton-flavor violation searches.Comment: 12 pages, 4 figures, 5 table

Present status of the nonstrange and other flavor partners of the exotic Theta+ baryon

Given the existing empirical information about the exotic Theta+ baryon, we analyze possible properties of its SU(3)F-partners, paying special attention to the nonstrange member of the antidecuplet N*. The modified piN partial-wave analysis presents two candidate masses, 1680 MeV and 1730 MeV. In both cases, the N* should be rather narrow and highly inelastic. Our results suggest several directions for experimental studies that may clarify properties of the antidecuplet baryons, and structure of their mixing with other baryons. Recent experimental evidence from the GRAAL and STAR Collaborations could be interpreted as observations of a candidate for the Theta+ nonstrange partner.Comment: 4 pages, 1 figure, talk given at the Topical Group on Hadron Physics (Fermilab, Oct. 24-26, 2004

Resonances, and mechanisms of Theta-production

After explaining necessity of exotic hadrons, we discuss mechanisms which could determine production of the exotic Theta-baryon. A possible important role of resonances (producing the Theta in real or virtual decays) is emphasized for various processes. Several experimental directions for studies of such resonances, and the Theta itself, are suggested. We briefly discuss also recent negative results on the Theta-baryon.Comment: 6 page

Weak radiative hyperon decays, Hara's theorem and the diquark

Weak radiative hyperon decays are discussed in the diquark-level approach. It is pointed out that in the general diquark formalism one may reproduce the experimentally suggested pattern of asymmetries, while maintaining Hara's theorem in the SU(3) limit. At present, however, no detailed quark-based model of parity-violating diquark-photon coupling exists that would have the necessary properties.Comment: 10 pages, LaTe

Monte Carlo simulation for jet fragmentation in SUSY-QCD

We present results from a new Monte Carlo simulation for jet fragmentation in QCD and SUSY QCD for large primary energies $\sqrt s$ up to $10^{16}$ GeV. In the case of SUSY QCD the simulation takes into account not only gluons and quarks as cascading particles, but also their supersymmetric partners. A new model-independent hadronization scheme is developed, in which the hadronization functions are found from LEP data. An interesting feature of SUSY QCD is the prediction of a sizeable flux of the lightest supersymmetric particles (LSPs), if R-parity is conserved. About 10% of the jet energy is transferred to LSPs which, owing to their harder spectra, constitute an important part of the spectra for large $x=E/E_{jet}$. Spectra of protons and of secondary particles, photons and neutrinos, are also calculated. These results have implications for the decay of superheavy particles with masses up to the GUT scale, which have been suggested as a source of ultrahigh energy cosmic rays.Comment: latex, 25 pages with 17 eps figure

Towards a common origin of the elliptic flow, ridge and alignment

It is claimed that elliptic flow, ridge and alignment are effects of azimuthal asymmetry, which have a common origin evolving with primary energy and stemming from the general structure of field-theoretical matrix elements. It interrelates a new ridge-phenomenon, recently found at the LHC and RHIC, with known coplanarity feature observed in collider jet physics as well as in cosmic ray studies.Comment: 4 pages, few typos fixed, reference added, version published in JETP Letter

Comment on "Hara's theorem in the constituent quark model"

It is pointed out that current conservation alone does not suffice to prove Hara's theorem as it was claimed recently. By explicit calculation we show that the additional implicit assumption made in such "proofs" is that of a sufficiently localized current.Comment: 8 pages, Late