118836742
Tensor force and shape evolution of Si isotopes in the Skyrme-Hartree-Fock model
Much interest has recently been devoted to the shape evolution of neutron-rich Si isotopes both experimentally and theoretically. We present our study of Si28-42 using the Skyrme-Hartree-Fock model with the Bardeen-Cooper-Schrieffer approximation for the pairing channel. We use an empirical pairing parameter deduced from the experimental binding energy data for each nucleus and each Skyrme parametrization. The recent highlight of the deformation change from the prolate shape of Si-38 to the oblate shape of Si-42 is confirmed in the present model. We also emphasize the role of the tensor force in deformations of neutron-rich Si-30,Si-32, and discuss its underlying physics.
118278930
Tensor correlation, pairing interaction, and deformation in Ne isotopes and Ne hypernuclei
We study tensor and pairing effects on the quadruple deformation of neon isotopes based on a deformed Skyrme-Hartree-Fock model with BCS approximation for the pairing channel. We extend the SkyrmeHartree-Fock formalism for the description of single- and d ouble-lambda hypernuclei adopting two different hyperon-nucleon interactions. It is found that the inte rplay of pairing and tensor interactions is crucial to derive the deformations in several neon isotopes. Especi ally, the shapes of 26,30 Ne are studied in details in comparisons with experimentally observed shapes. Furthermore the deformations of the hypernuclei are compared with the corresponding neon isotopic cores in the presence of tensor force. We find the same shapes with somewhat smaller deformations for single Λ-hypernuclei compared with their core deformations. It is also pointed out that the latest version of hyper on interaction, the ESC08b model, having a deeper Λ potential makes smaller deformations for hypernuclei than those of another NSC97f model.
120362009
Effect of tensor force on the shell structure of superheavy nuclei
Conference Name:11th International Conference on Nucleus-Nucleus Collisions, NN 2012. Conference Address: San Antonio, TX, United states. Time:May 27, 2012 - June 1, 2012.
118531588
Protoneutron stars in the Brueckner-Hartree-Fock approach and finite-temperature kaon condensation
National Natural Science Foundation of China [10605018, 10905048, 10975116]; Chinese Academy of Sciences [KJCX3-SYW-N2]; Program for New Century Excellent Talents in University [NCET-07-0730]; European Commission [CN/ASIA-LINK/008(94791)]; European Scienc
121212177
Hypernuclei in the deformed Skyrme-Hartree-Fock approach
The properties of Lambda hypernuclei in a broad mass region are studied by using a deformed Hartree-Fock approach using realistic nucleonic Skyrme forces, pairing correlations, and a microscopically determined lambda-nucleon interaction based on Brueckner-Hartree-Fock calculations of hypernuclear matter. The results suggest that the core nuclei and the corresponding hypernuclei have similar deformations with the same sign. Some light single-Lambda hypernuclei are substantially deformed and the Lambda binding energy is modified by the deformation.
120746694
Effect of tensor interaction on deformation and shell structure of medium-heavy and superheavy nuclei
Japanese Ministry of Education, Culture, Sports, Science and Technology [(C (2)) 20 540 277]; National Science Foundation of China [10 975 116]; Program for New Century Excellent Talents in University [NCET-07-0730]; Fundamental Research Funds for the Central Universities [2010 121 011]
124058283
Dynamical deformation in heavy ion collisions and formation of superheavy nuclei
118308331
A COMPARISON OF HARD X-RAY PHOTON INDICES AND IRON Kα EMISSION LINES IN X-RAY LUMINOUS NARROW- AND BROAD-LINE SEYFERT 1 GALAXIES
We use publicly available XMM-Newton data to systematically compare the hard X-ray photon indices, Γ2-10 keV , and the iron Kα emission lines of narrow- and broad-line Seyfert 1 (NLS1 and BLS1) galaxies. We compile a flux-limited (f 2-10 keV ≥ 1 × 10–12 erg s–1 cm–2) sample including 114 radio-quiet objects, with the 2-10 keV luminosity ranging from 1041 to 1045 erg s–1. Our main results are: (1) NLS1s and BLS1s show similar luminosity distributions; (2) the weighted means of Γ2-10 keV of NLS1s, BLS1s, and the total sample are 2.04 ± 0.04, 1.74 ± 0.02, and 1.84 ± 0.02, respectively; a significant anti-correlation between Γ2-10 keV and FWHMHβ suggests that Γ2-10 keV > 2.0 may be taken to indicate the X-ray luminous NLS1 type; (3) the 6.4 keV narrow iron Kα lines from NLS1s are generally weaker than that from BLS1s; this would indicate a smaller covering factor of the dusty tori in NLS1s if the line emission originates from the inner boundary region of the dusty torus in an active galactic nucleus; and (4) all the broadened iron Kα lines with intrinsic width σ>0.5 keV correspond to FWHMHβ ≤4000 km s–1.
123628224
Competing fusion and quasifission reaction mechanisms in the production of superheavy nuclei
Within the framework of a dinuclear system model, a new master equation is constructed and solved, which includes the relative distance of nuclei as a new dynamical variable in addition to the mass asymmetry variable so that the nucleon transfer, which leads to fusion and the evolution of the relative distance, which leads to quasifission (QF) are treated simultaneously in a consistent way. The QF mass yields and evaporation residual cross sections to produce superheavy nuclei are systematically investigated under this framework. The results fit the experimental data well. It is shown that the Kramers formula gives results of QF, which agree with those by our diffusion treatment, only if the QF barrier is high enough. Otherwise some large discrepancies occur.
118630598
Calibrating the correlation between black hole mass and X-ray variability amplitude: X-ray only black hole mass estimates for AGNs and ULXs
51813822
Ionization structure and Fe K$\alpha$ energy for irradiated accretion disks
We study the radial ionization structure at the surface of an X-ray illuminated accretion disk. We plot the expected iron K$\alpha$ line energy as a function of the Eddington ratio and of the distance of the emitting matter from the central source, for a non-rotating and a maximally-rotating black hole. We compare the predicted disk line energies with those measured in an archival sample of active galactic nuclei observed with {\it Chandra}, {\it XMM-Newton} and {\it Suzaku}, and discuss whether the line energies are consistent with the radial distances inferred from reverberation studies. We also suggest using rapidly-variable iron K$\alpha$ lines to estimate the viscosity parameter of an accretion disk. There is a forbidden region in the line energy versus Eddington ratio plane, at low Eddington ratios, where an accretion disk cannot produce highly-ionized iron K$\alpha$ lines. If such emission is observed in low-Eddington-ratio sources, it is either coming from a highly-ionized outflow, or is a blue-shifted component from fast-moving neutral matter.