The basic K nuclear cluster K- pp and its enhanced formation in the p + p -> K+ + X reaction

We have studied the structure of K- pp nuclear cluster comprehensively by solving this three-body system exactly in a variational method starting from the Ansatz that the Lambda(1405) resonance (Lambda*) is a K-p bound state. We have found that our original prediction for the presence of K-pp as a compact bound system with M = 2322$MeV/c2, B = 48 MeV and Gamma = 60 MeV remains unchanged by varying the Kba-rN and NN interactions widely as far as they reproduce Lambda(1405). The structure of K- pp reveals a molecular feature, namely, the K- in Lambda* as an "atomic center" plays a key role in producing strong covalent bonding with the other proton. We have shown that the elementary process, p + p -> K+ + Lambda* + p, which occurs in a short impact parameter and with a large momentum transfer (Q ~ 1.6$ GeV/c), leads to unusually large self-trapping of Lambda* by the participating proton, since the Lambda*-p system exists as a compact doorway state propagating to K- pp (R{Lambda*-p} ~ 1.67 fm).Comment: 18 pages, 14 figures. Phys, Rev. C, in pres

Kaonic nuclei studied based on a new framework of Antisymmetric Molecular Dynamics

We have developed a new framework of Antisymmetrized Molecular Dynamics (AMD), to adequately treat the I=0 \={K}N interaction, which is essential to study kaonic nuclei. The improved points are 1) pK$^-$/n\={K}$^0$ mixing and 2) total spin and isospin projections. These improvements enable us to investigate various kaonic nuclei (ppnK$^-$, pppK$^-$, pppnK$^-$, $^6$BeK$^-$ and $^9$BK$^-$) systematically. We have found that they are deeply bound and extremely dense with a variety of shapes.Comment: 10 pages, 5 figure

Emission spectra and invariant masses of Lambda and p in the stopped-K-NN absorption process in 4He and 6Li

We have calculated the emission spectra of Y and N and invariant masses of YN pairs in the direct K-NN --> YN absorption process at rest in 4He and light nuclei in order to provide theoretical tools for correct interpretations of experimental data with or without invoking kaonic nuclear bound states. All the momentum distributions are broad with widths around 150-200 MeV/c (except for the case of 6Li target), while the partial invariant mass of each YN pair has a peak around 2310-2330 MeV/c2. We argue against the interpretations of stopped-K- experimental data of KEK and FINUDA by Oset and Toki and by Magas, Oset, Ramos and Toki.Comment: 29 pages, 15 figure

Scaling Limits for the System of Semi-Relativistic Particles Coupled to a Scalar Bose Field

In this paper the Hamiltonian for the system of semi-relativistic particles interacting with a scalar bose field is investigated. A scaled total Hamiltonian of the system is defined and its scaling limit is considered. Then the semi-relativistic Schrodinger operator with an effective potential is derived

Promoting Effext of CO2 on the Degradation of Polyethylene to Ethylene and Propylene Over HZSM-5 Catalyst

As a part of the recycling of waste plastics, degradation of polyethylene to ethylene and propylene with HZSM-5 catalyst was studied by using a two-step process (thermal cracking and catalytic cracking). In the first stage, thermal cracking of high density polyethylene (HDPE) was carried out at 450-500℃. Yields of the cracked oil from HDPE were 79% at 450℃ and 88% at 500℃, respectively. Hydrocarbons of C7-C20 were the predominant products in the cracked oil. Higher hydrocarbons (>C20) increased with increasing reaction temperature. In the second stage, in order to obtain lower alkenes (mainly C_2H_4 and C_3H_6), the catalytic cracking of the thermally-cracked oil obtained in the first stage was carried out using a HZSM-5 catalyst at 600℃ in N_2 and CO_2 atmospheres. Since the cracked oil was difficult to handle, n-C_H_, which was a representative product in the thermal cracking of HDPE, was employed as a model compound. HZSM-5 catalyst increased the C1-C4 gas yield to 50% and C_2H_4 + C_3H_6 yield to 12% in N_2 atmosphere. On the other hand, in CO_2 atmosphere the gas yield reached 61% and C_2H_4 + C_3H_6 yield reached 30%, respectively. Addition of CO_2 promoted the catalytic cracking of n-C_H_^ with HZSM-5 to give C_2H_4 + C_3H_6

High-density \={K} nuclear systems with isovector deformation

Using a phenomenological \={K}N potential which reproduces $\Lambda$(1405) as an I=0 bound state of \={K}N, we investigated deeply bound kaonic nuclei, ppnK$^-$ and $^8$BeK$^-$, with the method of Antisymmetrized Molecular Dynamics. Our calculations show that strongly bound kaonic nuclear systems with unusual exotic structures are formed around the K$^-$, which attracts the surrounding nucleons to an extremely high-density assembly and induces a proton-neutron separation, ``isovector deformation''.Comment: 4 pages, 11 figures, submitted to Phys. Rev. Let

Strange tribaryons as Kbar-mediated dense nuclear systems

We discuss the implications of recently discovered strange tribaryons in 4He(stopped-K-, p)S0 (3115) and 4He(stopped-K, n) S1 (3140) within the framework of deeply bound kbar states formed on shrunk nuclear cores. S1 (3140) corresponds to T=0 ppnK-, whereas S0 (3115) to T=1 pnnK-, which is an isobaric analog state of pppK-, predicted previously. The observed binding energies can be accounted for by including the relativistic effect and by invoking a medium-enhanced kbar-N interaction by 15%. We propose various experimental methods to further study these and related bound systems.Comment: 8 pages, 6 figure

REMOVAL OF Cs+ USING ZEOLITE RHO

Radioactive Cs+ in water needs to be removed to prevent health problems in humans and animals. After the Fukushima nuclear power plant explosion, Cs+ has been removed by ion-exchange using zeolites such as Chabazite and Mordenite. To reduce the amount of contaminated zeolite waste, more efficient zeolite is needed. Zeolite RHO is a zeolite with a low Si/Al ratio, and a high ion-exchange capacity is expected. Thus, zeolite RHO was prepared using the conventional hydrothermal synthesis method and characterized by X-ray diffraction (XRD), adsorption/desorption isotherm of nitrogen, and elemental analysis by X-ray fluorescence (XRF) and inductively-coupled plasma spectroscopy (ICP). Removal of Cs+ was performed batch-wise in water and artificial seawater. Zeolite RHO showed promising Cs removal ability even in artificial seawater