49,662 research outputs found
Superfluidity of hyperons in neutron stars
We study the superfluidity of hyperons in neutron star
matter and neutron stars. We use the relativistic mean field (RMF) theory to
calculate the properties of neutron star matter. In the RMF approach, the
meson-hyperon couplings are constrained by reasonable hyperon potentials that
include the updated information from recent developments in hypernuclear
physics. To examine the pairing gap of hyperons, we employ
several interactions based on the Nijmegen models and used in
double- hypernuclei studies. It is found that the maximal pairing gap
obtained is a few tenths of a MeV. The magnitude and the density region of the
pairing gap are dependent on the interaction and the treatment
of neutron star matter. We calculate neutron star properties and find that
whether the superfluidity of hyperons exists in the core of
neutron stars mainly depends on the interaction used.Comment: 22 pages, 2 Tables, 6 Figur
Adder Based Residue to Binary Number Converters for (2n - 1; 2n; 2n + 1)
Copyright © 2002 IEEEBased on an algorithm derived from the new Chinese remainder theorem I, we present three new residue-to-binary converters for the residue number system (2n-1, 2n, 2n+1) designed using 2n-bit or n-bit adders with improvements on speed, area, or dynamic range compared with various previous converters. The 2n-bit adder based converter is faster and requires about half the hardware required by previous methods. For n-bit adder-based implementations, one new converter is twice as fast as the previous method using a similar amount of hardware, whereas another new converter achieves improvement in either speed, area, or dynamic range compared with previous convertersYuke Wang, Xiaoyu Song, Mostapha Aboulhamid and Hong She
User's Guide for ERB 7 Matrix. Volume 1: Experiment Description and Quality Control Report for Year 1
The Nimbus 7 ERB MATRIX Tape is a computer program in which radiances and irradiances are converted into fluxes which are used to compute the basic scientific output parameters, emitted flux, albedo, and net radiation. They are spatially averaged and presented as time averages over one-day, six-day, and monthly periods. MATRIX data for the period November 16, 1978 through October 31, 1979 are presented. Described are the Earth Radiation Budget experiment, the Science Quality Control Report, Items checked by the MATRIX Science Quality Control Program, and Science Quality Control Data Analysis Report. Additional material from the detailed scientific quality control of the tapes which may be very useful to a user of the MATRIX tapes is included. Known errors and data problems and some suggestions on how to use the data for further climatologic and atmospheric physics studies are also discussed
Reduced hierarchy equations of motion approach with Drude plus Brownian spectral distribution: Probing electron transfer processes by means of two- dimensionalcorrelation spectroscopy
We theoretically investigate an electron transfer (ET) process in a
dissipative environment by means of two-dimensional (2D) correlation
spectroscopy. We extend the reduced hierarchy equations of motion approach to
include both overdamped Drude and underdamped Brownian modes. While the
overdamped mode describes the inhomogeneity of a system in the slow modulation
limit, the underdamped mode expresses the primary vibrational mode coupled with
the electronic states. We outline a procedure for calculating 2D correlation
spectrum that incorporates the ET processes. The present approach has the
capability of dealing with system-bath coherence under an external
perturbation, which is important to calculate nonlinear response functions for
non-Markovian noise. The calculated 2D spectrum exhibits the effects of the ET
processes through the presence of ET transition peaks along the
axis, as well as the decay of echo signals.Comment: 28 pages, 8 figures; J. Chem. Phys. 137 (2012
TEM investigation of YBa2Cu3O7 thin films on SrTiO3 bicrystals
YBa2Cu3O7 films in c-axis orientation on bicrystalline SrTiO3 substrates are investigated by TEM. The films and the substrates are examined in cross-section and in plane view. The grain boundary of the bicrystal substrate contains (110) faceted voids, but is otherwise straight on a nanometer scale. Contrary to this, the film grain boundary is not straight grain boundary can be up to 100 nm for a 100 nm thick film. The deviation from the intended position of the YBCO grain boundary can already occur at the film/substrate interface where it can be as much as ±50 nm
Complete relativistic equation of state for neutron stars
We construct the equation of state (EOS) in a wide density range for neutron
stars using the relativistic mean field theory. The properties of neutron star
matter with both uniform and non-uniform distributions are studied
consistently. The inclusion of hyperons considerably softens the EOS at high
densities. The Thomas-Fermi approximation is used to describe the non-uniform
matter, which is composed of a lattice of heavy nuclei. The phase transition
from uniform matter to non-uniform matter occurs around ,
and the free neutrons drip out of nuclei at about $2.4 \times 10^{-4}\
\rm{fm^{-3}}$. We apply the resulting EOS to investigate the neutron star
properties such as maximum mass and composition of neutron stars.Comment: 23 pages, REVTeX, 9 ps figures, to appear in Phys. Rev.
- …