TO SEARCH FOR THE EXOTIC TENSOR MESON IN THE ρ+ρ+ AND ρ−ρ− CHANNELS IN HADRON COLLISIONS AT INTERMEDIATE ENERGIES

1992 ◽  
Vol 07 (18) ◽  
pp. 4313-4333 ◽  
Author(s):  
N.N. ACHASOV ◽  
G.N. SHESTAKOV

It is shown that reactions with one-pion exchange, reactions of meson production in the central region and reactions of nucleon-antinucleon annihilation can be good laboratories to search, in the ρ+ρ+ and ρ−ρ−channels, for the exotic resonance states E++ and E−− with IG(JP)=2+(2+), the signs of the neutral partner of which were discovered probably in the reactions γγ→ρρ. Detailed estimates are presented for the cross sections of the reactions π+p→E++n→ρ+ρ+n, π−ρ→E−−Δ++→ρ−ρ−∆++, ρρ→n(E++)n→n(ρ+ρ+)n and similar ones at intermediate energies.

2019 ◽  
Vol 35 (08) ◽  
pp. 2050045
Author(s):  
Pardeep Singh ◽  
Monika Singh ◽  
Neha Rani

The nuclear isotopic structure can be understood easily via the intermediate-energy charge exchange reactions of (p, n) and [Formula: see text]He, [Formula: see text] type. In the current contribution, we present some results for charge exchange reactions induced by 3He on targets lying in mass region [Formula: see text] within the theoretical framework of plane wave impulse approximation (PWIA) and distorted wave impulse approximation (DWIA). Here, the recoil effects in PWIA have also been considered. Particularly, the angular distributions and the unit cross-sections have been calculated and compared with the available data. Further, the importance of inclusion of the exchange contribution in these reactions is also considered, which eventually enhance the matching with data.


2010 ◽  
Vol 19 (05n06) ◽  
pp. 894-902 ◽  
Author(s):  
L. P. KAPTARI ◽  
B. KÄMPFER

The production of pseudo scalar, η, η′, and vector, ω, ρ, ϕ, mesons in NN collisions at threshold-near energies is analyzed within a covariant effective meson-nucleon theory. It is shown that a good description of cross sections and angular distributions, for vector meson production, can be accomplished by considering meson and nucleon currents only, while for pseudo scalar production an inclusion of nucleon resonances is needed. The di-electron production from subsequent Dalitz decay of the produced mesons, η′ → γγ* → γe+e- and ω → πγ* → πe+e- is also considered and numerical results are presented for intermediate energies and kinematics of possible experiments with HADES, CLAS and KEK-PS. We argue that the transition form factor ω → γ*π as well as η′ → γ*γ can be defined in a fairly model independent way and the feasibility of an experimental access to transition form factors is discussed.


2004 ◽  
Vol 19 (07) ◽  
pp. 1099-1110 ◽  
Author(s):  
Y. YAMAZAKI

A review is given of the measurements of the diffractive process in recent years from two high-energy colliders, the HERA ep collider and the Tevatron [Formula: see text] collider. The energy dependence of the cross sections and the factorisation properties of diffractive processes are discussed.


1987 ◽  
Vol 65 (6) ◽  
pp. 614-625 ◽  
Author(s):  
J. Wambach

The (p, n) and (n, p) charge-exchange reactions are a suitable tool in nuclear-structure studies. At intermediate energies, the interaction with the target resembles that between free nucleons, which makes the probes mostly susceptible to the spin dynamics of the nucleus. We review the current theoretical picture of nucleon–nucleus charge-exchange reactions. A brief introduction to the theory of direct reactions in the impulse approximation is given. We then discuss the random-phase approximation (RPA) linear response theory, which is widely used in the calculation of cross sections and related observables. To understand correctly the shape of the continuum cross sections, one needs a more sophisticated theory. We discuss suitable extensions of the RPA that incorporate spreading effects as well as escape effects. Charge-exchange reactions of the (n, p) type have important implications for the evolution of massive stars. The relevance for Type-II supernovae is discussed.


2007 ◽  
Vol 22 (32) ◽  
pp. 6219-6226
Author(s):  
PORNRAD SRISAWAD ◽  
YU-MING ZHENG ◽  
CHRISTIAN FUCHS ◽  
AMAND FAESSLER ◽  
YUPENG YAN ◽  
...  

The production of the sigma (σ) meson is investigated in the quantum molecular dynamics model for the p+A reactions with the nuclei A being 12 C , 40 Ca and 208 Pb at the incident proton energies Ep = 1.50 GeV . The simulation results indicates a distinctive A dependence of the sigma production, that is, the increase of A is followed by an increase of the production cross-sections. The σ meson production in proton induced reactions is strongly medium-dependent, and the produced σ mesons decaying in a denser medium experience a stronger mass shift towards lower masses. This mass shift is an experimentally accessible observable in the final state pion pairs which did not suffer reabsorption by the surrounding nucleons. It is pointed out that the ratio of the simulation results of measurable σ mesons (in the form of two pions) cross-sections as a function of the sigma invariant-mass from various reactions opens the possibility to address experimentally the mass shift of the σ in a dense nuclear environment.


2016 ◽  
Vol 25 (11) ◽  
pp. 1650095
Author(s):  
Valery I. Kovalchuk

A general analytical expressions for the cross-section and the polarization of nucleons arising in the inclusive deuteron stripping reaction have been derived in the diffraction approximation. The nucleon–nucleus phases were calculated in the framework of Glauber formalism and making use of the double-folding potential. The tabulated distributions of the target nucleus density and the realistic deuteron wave function with correct asymptotic at large nucleon–nucleon distances were used. The calculated angular dependences for the cross-sections and the analyzing powers of the [Formula: see text] reaction are compared with corresponding experimental data.


1971 ◽  
Vol 32 (1) ◽  
pp. 7-9 ◽  
Author(s):  
J. Galin ◽  
D. Guerreau ◽  
M. Lefort ◽  
X. Tarrago

The work of multilayer glass structures for central and eccentric compression and bending are considered. The substantiation of the chosen research topic is made. The description and features of laminated glass for the structures investigated, their characteristics are presented. The analysis of the results obtained when testing for compression, compression with bending, simple bending of models of columns, beams, samples of laminated glass was made. Overview of the types and nature of destruction of the models are presented, diagrams of material operation are constructed, average values of the resistance of the cross-sections of samples are obtained, the table of destructive loads is generated. The need for development of a set of rules and guidelines for the design of glass structures, including laminated glass, for bearing elements, as well as standards for testing, rules for assessing the strength, stiffness, crack resistance and methods for determining the strength of control samples is emphasized. It is established that the strength properties of glass depend on the type of applied load and vary widely, and significantly lower than the corresponding normative values of the strength of heat-strengthened glass. The effect of the connecting polymeric material and manufacturing technology of laminated glass on the strength of the structure is also shown. The experimental values of the elastic modulus are different in different directions of the cross section and in the direction perpendicular to the glass layers are two times less than along the glass layers.


Sign in / Sign up

Export Citation Format

Share Document