41,470 research outputs found

    Challenge on the Astrophysical R-process Calculation with Nuclear Mass Models

    Full text link
    Our understanding of the rapid neutron capture nucleosynthesis process in universe depends on the reliability of nuclear mass predictions. Initiated by the newly developed mass table in the relativistic mean field theory (RMF), in this paper the influence of mass models on the rr-process calculations is investigated assuming the same astrophysical conditions. The different model predictions on the so far unreachable nuclei lead to significant deviations in the calculated r-process abundances.Comment: 3 pages, 3 figure

    Solid-state interdiffusion reactions in Ni/Ti and Ni/Zr multilayered thin films

    Get PDF
    We have performed a comparative transmission electron microscopy study of solid-state interdiffusion reactions in multilayered Ni/Zr and Ni/Ti thin films. The Ni-Zr reaction product was amorphous while the Ni-Ti reaction product was a simple intermetallic compound. Because thermodynamic and chemical properties of these two alloy systems are similar, we suggest kinetic origins for this difference in reaction product

    Effective field theory for triaxially deformed nuclei

    Full text link
    Effective field theory (EFT) is generalized to investigate the rotational motion of triaxially deformed even-even nuclei. A Hamiltonian, called the triaxial rotor model (TRM), is obtained up to next-to-leading order (NLO) within the EFT formalism. Its applicability is examined by comparing with a five-dimensional collective Hamiltonian (5DCH) for the description of the energy spectra of the ground state and γ\gamma band in Ru isotopes. It is found that by taking into account the NLO corrections, the ground state band in the whole spin region and the γ\gamma band in the low spin region are well described. The results presented here indicate that it should be possible to further generalize the EFT to triaxial nuclei with odd mass number.Comment: 21 pages, 9 figure

    Doublet bands in 126^{126}Cs in the triaxial rotor model coupled with two quasiparticles

    Get PDF
    The positive parity doublet bands based on the πh11/2νh11/2\pi h_{11/2}\otimes\nu h_{11/2} configuration in 126^{126}Cs have been investigated in the two quasi-particles coupled with a triaxial rotor model. The energy spectra E(I)E(I), energy staggering parameter S(I)=[E(I)E(I1)]/2IS(I)=[E(I)-E(I-1)]/2I, B(M1)B(M1) and B(E2)B(E2) values, intraband B(M1)/B(E2)B(M1)/B(E2) ratios, B(M1)in/B(M1)outB(M1)_{\textrm{in}}/B(M1)_{\textrm{out}} ratios, and orientation of the angular momentum for the rotor as well as the valence proton and neutron are calculated. After including the pairing correlation, good agreement has been obtained between the calculated results and the data available, which supports the interpretation of this positive parity doublet bands as chiral bands.Comment: Phys.Rev.C (accepted

    An Efficient Method for GPS Multipath Mitigation Using the Teager-Kaiser-Operator-based MEDLL

    Get PDF
    An efficient method for GPS multipath mitigation is proposed. The motivation for this proposed method is to integrate the Teager-Kaiser Operator (TKO) with the Multipath Estimating Delay Lock Loop (MEDLL) module to mitigate the GPS multipath efficiently. The general implementation process of the proposed method is that we first utilize the TKO to operate on the received signal’s Auto-Correlation Function (ACF) to get an initial estimate of the multipaths. Then we transfer the initial estimated results to the MEDLL module for a further estimation. Finally, with a few iterations which are less than those of the original MEDLL algorithm, we can get a more accurate estimate of the Line-Of-Sight (LOS) signal, and thus the goal of the GPS multipath mitigation is achieved. The simulation results show that compared to the original MEDLL algorithm, the proposed method can reduce the computation load and the hardware and/or software consumption of the MEDLL module, meanwhile, without decreasing the algorithm accuracy

    Behavior of the collective rotor in nuclear chiral motion

    Full text link
    The behavior of the collective rotor in the chiral motion of triaxially deformed nuclei is investigated using the particle rotor model by transforming the wave functions from the KK-representation to the RR-representation. After examining the energy spectra of the doublet bands and their energy differences as functions of the triaxial deformation, the angular momentum components of the rotor, proton, neutron, and the total system are investigated. Moreover, the probability distributions of the rotor angular momentum (RR-plots) and their projections onto the three principal axes (KRK_R-plots) are analyzed. The evolution of the chiral mode from a chiral vibration at the low spins to a chiral rotation at high spins is illustrated at triaxial deformations γ=20\gamma=20^\circ and 3030^\circ.Comment: 21 pages, 6 figure
    corecore