Doubly charmed dibaryon states

In this work, we study the doubly charmed dibaryon states with the qqqqcc(q = u, d, s) configuration.The mass spectra of doubly charmed dibaryon states are obtained systematically within the chromomagnetic interaction model. In addition to the mass spectrum analysis, we illustrate their two-body strong decay behaviours. Our results suggest that there may be narrow states or even stable states that cannot decay through the strong interaction. We hope that our results will provide valuable informa...     

Search for dibaryon production in 4Hep interactions at intermediate energies

With the aid of the 2-m liquid-hydrogen bubble chamber constructed at the Institute of Theoretical and Experimental Physics (ITEP, Moscow), ⁴Hep interactions are studied at primary alpha-particle momenta of 2.7 and 5 GeV/c (the respective kinetic energies of primary protons in the ⁴He rest frame are T _p=220 and 620 MeV). The effective-mass spectra of two nucleons from the reactions ⁴Hep → dppn and ⁴Hep → pppnn are analyzed. The effective-mass spectrum of the two-proton system produced in the quasielastic-charge-exchange reaction p ⁴He → n _F(pp)d at T _p=620 MeV (here, n _F stands for the fast neutron in the ⁴He rest frame) shows a narrow peak, which is indicative of the existence of a dibaryon whose mass and width are M _2p =2008±13 MeV and Γ _2p =0±5 MeV, respectively. In the mass spectra of the two-proton system from the reactions p ⁴He → n _F(pp)d and p ⁴He → p _F(pp)(nn), narrow threshold peaks are also found at a mass of M _2p ?1878–1879 MeV.     

Possible dibaryon production at (P)anda with a Lagrangian approach

In order to confirm the existence of the dibaryon state d*(2380) observed at WASA@COSY,we estim-ate the cross section for production of the possible dibaryon an...     

Constant-cutoff approach toSU(3)-symmetry breaking for strange dibaryon states

We suggest a quantum stabilization method for theSU(2)-model, based on the constant-cutoff limit of the cutoff quantization method developed by Balakrishnaet al., which avoids the difficulties with the usual soliton boundary conditions pointed out by Iwasaki and Ohyama. We investigate the baryon numberB = 1 sector of the model and show that after the collective coordinate quantization it admits a stable soliton solution which depends on a single dimensional arbitrary constant. We then show that the approach toSU(3)-symmetry breaking for strange dibaryon states proposed by Kopeliovichet al. can be simplified by omitting the Skyrme stabilizing term and using the constant-cutoff stabilization method. We derive the results for spectra of some strange and nonstrange dibaryon states and obtain the numerical results for the absolute masses of these states, in reasonable agreement with the values obtained, using the complete Skyrme model, by Kopeliovichet al.     

Novel mechanism of H0 dibaryon production in proton-proton interactions from parton-based Gribov-Regge theory

A novel mechanism of H0 and strangelet production in hadronic interactions within the Gribov-Regge approach is presented. In this approach the H0 is produced by the same mechanism as usual hadrons, namely, by disintegration of the remnant formed by the exchange of pomerons between the two protons. Rapidity and transverse momentum spectra of the observed hadrons are well described in this approach. In contrast to traditional distillation approaches, here the production of multiple (strange) quark bags does not require large baryon densities or a quark gluon plasma. We calculate the rapidity and transverse momentum distributions as well as the 4pi multiplicity of the H0 for sqrt[s]=17 GeV (Super Proton Synchrotron) and 200 GeV (Relativistic Heavy Ion Collider). In both cases the H0, if it exists, should be observable by the present experiments.     

Unstable states produced in multiparticle reactions

Normalized wavefunctions for unstable-particle states are constructed to meet the following physically plausible specifications. The wavefunctions of such states should enter into the theoretical production cross section in the same manner as the boundstate wavefunctions of stable particles. The cross section for the production of an unstable particle should be equal to the breakup cross section integrated over the resonance minus the background. For this purpose the multiparticle reaction cross section is brought into a form such that final-state resonances and interference corrections can be exhibited explicitly. The present theory is limited to unstable particles that decay into one or several two-body channels. For heuristic purposes, rearrangement and breakup scattering for three simple particles is treated numerically. For two particles interacting via a local potential, the wavefunction of the unstable state and the scattering phase shifts are computed with a simple algebraic technique. In order to treat complex multiparticle systems, we extend the resonance theory of simple two-particle systems to resonances in multiparticle two-body channels.     

Possible rotational states in odd In nuclei

Levels and transitions in ¹⁰⁷In and ¹⁰⁹In have been studied in in-beam spectroscopy on the reactions ¹⁰⁶Cd(d, nγ)¹⁰⁷In and ¹⁰⁸Cd(d, nγ)¹⁰⁹In. Low-lying $\text{1}\text{2}{}^{\mathrm{+}}\text{and}\text{3}\text{2}{}^{\mathrm{+}}$ states resembling the possible rotational bands observed in the heavier In isotopes are seen in both nuclei. The potential energy has been calculated for ^107–121In with the odd proton in different orbitals, using the Strutinsky normalization procedure. A prolate minimum at a deformation ε ≈ 0.2 is obtained for the lowest $\text{1}\text{2}{}^{\mathrm{+}}$ orbital, which is in good agreement with the experimental data for ^115–119In. The excitation energy of the $\text{1}\text{2}{}^{\mathrm{+}}$ minimum shows a fairly good agreement with experimental data.     

On the search for dibaryon states in kinematically complete measurements of the deuteron break up by pions

The possibilities of the search for dibaryon states in the deuteron break up by pions by means of the measurement of kinematically complete spectra are discussed. Such experiments provide the additional possibility to measure cross sections of the resonance in dependence on the transferred momentum. In this way one is able to prove the rigidity of the composite system, which may be considered as a signature of the 6q-nature of the found resonances.Presented at the symposium Mesons and Light Nuclei, Bechyn. Czechoslovakia, May 27–June 1, 1985.     

Possible origin of extra states in particle physics

The transformation of a discrete state into resonances is considered in the framework of The Friedrichs model. The number of resonances depends on the form factor which describes the interaction of the discrete state and the continuum and for a reasonable form this number exceeds the usual one-to-one correspondence. The physical implications of the phenomenon are discussed.     

Charge-constrained coherent pion states produced in nuclear matter

In a recent article, Bloss, Hone and Scalapino have used a simplified model Hamiltonian and Keldysh field theoretic methods to approximately calculate the power radiated as Cherenkov charged pions whose emission is triggered when a fast nucleon traverses nuclear matter. The model used by these authors conserves charge by flipping the isospin state of the fast nucleon alone for each charged pion emitted. Since it is the nuclear matter excited by the fast nucleon which should be largely reponsible for emitting the Cherenkov charged pions, we investigate an alternate model that allows all the disturbed nuclear matter to change its charge state when a charged pion is emitted—as an idealization, the emitting matter is assumed to have an infinite number of charge states, in contrast to the two of the fast nucleon. This modified model is shown to be exactly solvable in terms of charge-constrained coherent pion states; the power radiated as charged pions is found to be approximately twice that calculated by Bloss et al. from their model.     

Interpretation of collective hypernuclear states produced in strangeness-exchange reactions

The concept of Strangeness Analog Resonance may not be useful for describing low momentum transfer strangeness exchange reactions on nuclei. A band of collective excitations is expected where the lowest and most enhanced one is invariably around 10 MeV above hypernuclear ground state.     

Azimuthal structures of produced particles in heavy-ion interactions

The angular structures of particles produced in ²⁰⁸Pb at 158 A GeV/c and ¹⁹⁷Au at 11.6 A GeV/c induced interactions with Ag(Br) nuclei in emulsion detector have been investigated. Nonstatistical well-ordered ring-like structures of produced particles in azimuthal plane of a collision have been found, and their parameters have been determined. The text was submitted by the authors in English.     

Low-lying states and separabelized Skyrme interactions

A finite-rank separable approximation for the quasiparticle RPA calculations with Skyrme interactions that was proposed in our previous work is extended to take into account the coupling between one-and two-phonon terms in the wave functions of excited states. It is shown that the phonon-phonon coupling effect can be very important to reproduce experimental data.     

Entangled photon states in consecutive nonlinear optical interactions

Quantum theory of two consecutive light-wave parametric interactions with aliquant frequencies produced by a common pump wave in a crystal is developed. Using the differentiation method, the unitary evolution operator of the system is reduced to an ordered form that allows the calculation of the field state and the statistical characteristics of interacting waves. It is shown that, for the initial vacuum field state, the created photons obey the super-Poisson statistics at the interacting frequencies and are in a multiparticle entangled state.     

Antiferromagnetic interactions between localized states in amorphous germanium

The temperature dependence of the magnetic susceptibility (300 → 1.6°K) and ESR (300 → 6°K) of amorphous germanium have been determined. There is a temperature dependent paramagnetic term to the magnetic susceptibility due to a density of localized unpaired spins (dangling bonds) of 10¹⁹ spins/cm³. There is an antiferromagnetic interaction between at least some of these localized unpaired spins with an exchange energy estimated by various models to be on the order of a degree Kelvin.