On the competiting role of mean-field and residual interactions in flow observables

Theoretical analyses of heavy-ion reactions are performed in the framework of the semi-classical Landau-Vlasov approach. The incident energies are investigated in the range from intermediate to low energy regimes, where transverse collective motion has been experimentally evidenced. The influence of the equation of state (E.O.S.) parameters on various collective observables is studied in relation with the action of the residual interactions. From the sensitivity to both aspects, and taking into account the experimental biases limitations, our investigation indicates that E.O.S. signatures should be more expected at energies below 100 MeV per nucleon.     

Hadron production inpBe interactions at 14.6 GeV/c

Invariant cross sections for the production of ^±,K ^±,p, andd inpBe interactions at 14.6 GeV/c are well reproduced by calculations carried out in the framework of the Rossendorf collision model.Communicated by: F. Lenz     

Picosecond lifetime measurements in147Pm

Half-lives of excited levels in¹⁴⁷Pm have been measured using BaF₂ scintillators. New values of t_1/2 are 2420(10), 43(5), 22(9), 17(10) and 17(10) ps for the 91.1, 410.5, 489.2, 531.0 and 685.9 keV level, respectively. E2 enhancement factors of -transitions have been deduced.     

On the limits of induced radiation concept in FELs

We discuss a restriction of the induced radiation concept in classical beam systems due to accompanying spontaneous radiation (radiation friction). For short wave FELs, spontaneous radiation renders a noticeable influence on the phasing of particles, which is the base mechanism of induced radiation in classical systems. It leads to an essential restriction on the radiating system length and gain which cannot be compensated by an increase in the beam current. The text was submitted by the authors in English.     

Positron emission isotope production cyclotron in DLNP JINR (Status Report)

A C10-cyclotron for radioisotope production is under construction at the Dzhelepov Laboratory of Nuclear Problem, Joint Institute for Nuclear Research (DLNP JINR). It is a compact isochronous cyclotron for accelerating H⁻ ions to the energy of about 10 MeV. The magnetic system, vacuum chamber and accelerating system is being built now. Results of the calculation and forming of the cyclotron magnetic field and the study of the beam dynamics from an ion source to an extraction system in calculated magnetic field are presented. The text was submitted by the authors in English.     

Experimental studies of pulsed signal propagation from the shelf to deep sea

Results of an experimental study of low-frequency broadband pulsed signal propagation in a waveguide that includes the shelf zone, the continental slope, and the deep sea region are presented. Using phase-manipulated signals with central frequencies of 366 and 600 Hz, pulsed characteristics are measured at six points along the propagation track, the maximal distance from the source being 368 km. It is experimentally demonstrated that, in the presence of a negative sound velocity gradient in the near bottom layer on the shelf with a small bottom slope, the choice of the source position at the shelf bottom near the shoreline provides the formation of a continuous illumination zone in the deep sea near the USC axis and a stable pulsed characteristic with two main sound energy arrivals. The propagation velocity of the pulse that is last to arrive is identical (within the measurement error) to the velocity of sound on the USC axis at the point of reception. Possibilities for practical application of the results obtained from the experiment are discussed.     

Fast deuteron production from antiproton annihilation at rest on carbon and uranium targets

Deuteron yields from 20–350 MeV kinetic energy in antiproton annihilation at rest in¹²C and²³⁸U targets are compared with a coalescence model calculation. Agreement of the data with the model up to approximately 80 MeV is good. However, from 80 to 350 MeV the model increasingly underestimates the yield, by as much as on order of magnitude. These results, along with previously reported failures to explain proton spectra with first order rescattering of pions, suggest that other mechanisms are manifest in relatively rare, high energy light nucleus emission, e.g.B > 0 annihilations or possible six quark interactions.Work supported in part by the U.S. Air Force Office of Scientific Research and the National Science Foundation     

Study of fast target protons in high energy hadron-nucleus collisions

Intranuclear cascade model calculations are carried out on the recent measurements (WA80 Collaborations) for the multiplicity, energy and angular distributions of singly charged target fragments of energy in the range 30 E < 400=" mev=" (the=" so-called=" grey=" particles)=" produced=" in=" proton-nucleus=" interactions=" at=" 200=" gev/c.=" it=" is=" shown=" that=" these=" distributions=" are=" reasonably=" well=" understood=" in=" terms=" of=" the=" intranuclear=" cascade=" model=" which=" considers=" that=" grey=" particles=" are=" only=" produced=" in=" the=" first=" two=" generations=" of=" the=" cascade.=" the=" obtained=" distributions,=" mean=" values=" and=" target=" mass=" dependence=" are=" more=" consistent=" with=" the=" experimental=" data=" than=" other=" models=" using=" monte=" carlo=">     

M1-transitions and the mutual orientation of the unpaired nucleons in odd-odd nuclei

Experimental lifetimes and branching ratiosB(M1)/B(E2) are used to determine reduced M1-transition probabilities between collective-band levels withI=1 in^{102, 104, 106}Ag and in the odd-odd isotopes of La, Pr, Pm and Tl. The extractedB(M1) values are compared with calculations in the framework of the quasiclassical approximation and the model axial rotor+two quasiparticles. The reduced M1-transition probabilities along with the magnetic moments were found to depend on the mutual orientation of the angular momenta of the unpaired nucleons in the odd-odd nuclei.The authors would like to thank the staffs of Cyclotron Laboratory of P.T.I. in St. Petersburg and the Nuclear Moments Laboratory of I.N.R. in Kiev for assistance in the experiments. One of us (A.I.L.) wishes to thank the Sektion Physik of the Ludwig Maximilians Universität München for its hospitality and financial support.     

The effects of chemical etching of porous silicon on Raman spectra

We have investigated the effects of chemical etching on Raman spectra of porous silicon. The as-anodized porous silicon consisted mainly of crystalline silicon, as indicated by the Raman spectra. The background in the spectrum was strong, indicating that the porous silicon surface was rough due to the presence of pores. When chemical etching was performed five times, the Raman spectrum revealed the presence of spherically shaped nanocrystalline silicon whose diameter was around 3.5 nm. Further chemical etching, however, extinguished the nanocrystallites, in addition to smoothing the surface morphology.     

Spatial coherence measurements from two L-shape arrays in Shallow Water

In the Shallow Water’ 06 experiment, two L-shape arrays (ARRAY52 and ARRAY32) were deployed. The vertical line array (VLA) components of both ARRAY52 and ARRAY32 were exactly perpendicular to the direction of sound propagation. The horizontal line array (HLA) component of ARRAY52 was exactly perpendicular to the direction of sound propagation. The HLA component of ARRAY32 was exactly parallel to the direction of sound propagation. This configuration offered an opportunity to simultaneously analyze the three dimensional (3-D) spatial coherences: vertical, transverse horizontal and longitudinal horizontal. When the source and the receivers were below the thermocline, both the vertical and longitudinal horizontal coherence lengths in units of wavelength increased with increasing range and frequency. When the source was within the thermocline, the transverse horizontal coherence length in units of wavelength decreased with frequency and exhibited weak range dependence. The text was submitted by the authors in English.     

The development of a TESLA recirculator with superconducting accelerating structures in Ukraine

The recirculator project, which is to be built at the National Science Center, Kharkov Institute of Physics and Technology (NSC KIPT), is presented. The basic solutions incorporated in the design are given. The TESLA superconducting section is chosen as the accelerating structure of an accelerating complex. The text was submitted by the authors in English.     

Dirac magnetic monopole production from photon fusion in proton collisions

We calculate the lowest-order cross-section for Dirac magnetic monopole production from photon fusion ( in p collisions at = 1.96 TeV, pp collisions at = 14 TeV, and we compare with Drell-Yan (DY) production. We find the total cross-section is comparable with DY at = 1.96 TeV and dominates DY by a factor > 50 at = 14 TeV. We conclude that both the and DY processes allow for a monopole mass limit m > 370 GeV based upon the null results of the recent monopole search at the Collider Detector at Fermilab (CDF). We also conclude that production is the leading mechanism to be considered for direct monopole searches at the Large Hadron Collider (LHC).     

The project of a Tau-Charm Factory with Crab Waist in Novosibirsk

The project of a new-generation TCF is now under consideration in Novosibirsk. A novel approach of the Crab Waist collision scheme allows reaching a luminosity of 1–2 × 10³⁵ cm⁻² s⁻¹. The other features of the facility are as follows: variable energy from 3 GeV to 4.5 GeV (c.m.), electron beam polarization, flexible usage of damping and excitation wigglers to keep high luminosity for all energy levels, etc. We discuss some of the challenges and opportunities available with the development of the project. for the Novosibirsk Tau-Charm Factory team The text was submitted by the author in English.     

Possible odderon effects in inclusive hadron production

We consider the possible contribution of odderon (reggeon with α _Odd(0)∼1 and negative signature) exchange to the differences in the inclusive spectra of particle and antiparticle in the central region. The energies and/or accuracy of the currently available experimental data do not allow for a clear conclusion on the presence of an odderon component, but the upcoming LHC data should finally elucidate the question of the existence of the odderon.     

Investigations of electron beam characteristics using an accelerator based on a magnetron gun with a secondary-emission cathode

The reliability and service life of accelerating installations are substantially determined by the lifetime of electron sources. The accelerator under consideration has a magnetron gun with a channel-free cold secondary-emission cathode in crossed fields as an electron source [1, 2]. In the present work, the data of the electron beam parameters obtained in the accelerator based on the magnetron gun with a secondary-emission cathode are given, and possible secondary uses are suggested. The text was submitted by the authors in English.     

Dynamical origin of power spectra

We discuss a possible origin of Tsallis’ statistics from the correlation among constituents which reduces the phase space of the system. We also show that a system of coupled linear harmonic oscillators can exhibit a Tsallis-type behavior. This paper is part of the Topical Issue Statistical Power Law Tails in High-Energy Phenomena.     

Sound absorption by a solution of nanoparticles

Absorption of an acoustic wave in a colloidal solution via two mechanisms: due to viscous friction in the liquid and due to energy dissipation on nanoparticles is studied. The dependence of the imaginary part of the wave vector on the frequency is estimated in both cases. It is shown that in typical colloidal solutions, the first absorption mechanism dominates at low frequencies, and the second one, at higher, ultrasonic frequencies.     

Estimates of hypernuclear production via the exclusive (p,K+) reaction

We investigate the possibility of producing hypernuclei with proton beams via (p, K ⁺) reaction. We present differential cross sections calculations utilizing the distorted wave impulse approximation in momentum space. We consider the reactions¹²C(p,K ⁺) ¹³ and¹⁶O(p,K ⁺) ¹⁷ within the energy region 0.8 GeV1.2 GeV. We study both the case of formation of in S-state (¹²C) and P-state (¹⁶O). We take into account the contribution of both one-step and two-step processes when K pair is produced directly by incoming proton and intermediate pion, respectively. It is found that practically in all cases the two-step processes give significant contribution.Work supported by KFA Julich     

On the chaining dynamics of inclusions in SmC* free standing films

A simplified model of an inclusion represented by (+1)-wedge disclination and an accompanying hyperbolic defect ((−1)-wedge disclination) in smectic C* free standing films is used to describe the early stage of the ordering process of inclusions into chains. The elastic interaction between inclusions and their associated hyperbolic defects is used to discuss the dynamics observed experimentally during the inclusion chaining when inclusions are at distances much larger than their radii. This work was also supported by Grant No. 202/02/0840 of the Grant Agency of the Czech Republic and by the research project AV0Z1-010-914.