Lianggang Liu - Academia.edu (original) (raw)

Papers by Lianggang Liu

Research paper thumbnail of Energy of the gravitational field of slowly rotating neutron stars

Chinese Journal of Physics- Taipei-

Using the Einstein-Tolman expression. for the energy-momentum pseudo-tensor, the energy density o... more Using the Einstein-Tolman expression. for the energy-momentum pseudo-tensor, the energy density of the gravitational field of slowly rotating neutron stars was calculated in Cartesian coordinates. The energy density of the gravitational field could be expressed by the metric of the non-rotating neutron star and the angular velocity of the local inertial frames, accurate to the first order in the angular velocity of the star. A numerical method for calculating the energy density is given.

Research paper thumbnail of Muscle's Motion in an Overdamped Regime

Communications in Theoretical Physics, 2002

ABSTRACT

Research paper thumbnail of The Influence of the Renormalization Condition to the Equation of State of the Nuclear Matter

Communications in Theoretical Physics, 2001

ABSTRACT In the relativistic sigma-omega model, the influences of the parameters b, c, d in the p... more ABSTRACT In the relativistic sigma-omega model, the influences of the parameters b, c, d in the potential U(sigma) = (1/2!)b sigma (2) + (1/3!)c sigma (3) + (1/4!)d sigma (4) to the incompressibility, effective mass and binding energy of the nuclear matter are studied in detail. The calculation of equation of state of nuclear matter shows that the values of b, c, d depend on the renormalization condition, we also find that a soft equation of state of nuclear matter can be obtained in a suitable renormalization condition, and the experimental incompressibility coefficient can be reproduced. These results are also used to study the thermal properties of hot Delta -resonant nuclear matter.

Research paper thumbnail of Properties of Rotating Neutron Stars in the Relativistic σ-ω Model

Communications in Theoretical Physics, 2004

ABSTRACT The properties such as the moment of inertia, the surface redshift and the radius of gyr... more ABSTRACT The properties such as the moment of inertia, the surface redshift and the radius of gyration of rotating neutron stars in the relativistic sigma-omega model are studied with the Hartle's method. The relation between the angular velocity of the fluid relative to the local inertial frame and the uniform angular velocity relative to the infinite is calculated.

Research paper thumbnail of Tachyon Pole in sigma Meson Propagator in Nuclear Matter in the Relativistic sigma-omega Model

COMMUNICATIONS IN THEORETICAL …, 2001

... in quantum hadron dynamics,[1] and great efforts have been made to study it.[2,3] In meson-nu... more ... in quantum hadron dynamics,[1] and great efforts have been made to study it.[2,3] In meson-nucleon field theory, the large coupling constants are in-volved, and the mass corresponding to the tachyon pole of the meson propagators is of the same order as the nu-cleon mass ...

Research paper thumbnail of Facilitated movement of inertial Brownian motors driven by a load under an asymmetric potential

Research paper thumbnail of Exactly solvable single lane highway traffic model with tollbooths

Physica A: Statistical Mechanics and its Applications, 2002

Tolls are collected on many highways as a means of traffic control and revenue generation. Howeve... more Tolls are collected on many highways as a means of traffic control and revenue generation. However, the presence of tollbooths on highway surely slows down traffic flow. Here, we investigate how the presence of tollbooths affect the average car speed using a simple-minded single lane deterministic discrete traffic model. More importantly, the model is exactly solvable.

Research paper thumbnail of Stochastic resonance in a stochastic bistable system

Journal of Statistical Mechanics: Theory and Experiment, 2007

ABSTRACT

Research paper thumbnail of A channel Brownian pump powered by an unbiased external force

The Journal of Chemical Physics, 2008

A Brownian pump of particles in an asymmetric finite tube is investigated in the presence of an u... more A Brownian pump of particles in an asymmetric finite tube is investigated in the presence of an unbiased external force. The pumping system is bounded by two particle reservoirs. It is found that the particles can be pumped through the tube from a reservoir at low concentration to one at the same or higher concentration. There exists an optimized value of temperature (or the amplitude of the external force) at which the pumping capacity takes its maximum value. The pumping capacity decreases with increasing radius at the bottleneck of the tube.

Research paper thumbnail of Influence of self interaction of σ meson to the equation of state of nuclear matter

High Energy Physics and Nuclear Physics -Beijing-

In the relativistic sigma-omega model, the influence of the parameters in self-interaction of sig... more In the relativistic sigma-omega model, the influence of the parameters in self-interaction of sigma meson to the equation of state of normal nuclear matter, especially, to incompressibility, effective mass, and coupling constants, is studied in detail. We find that these parameters have an intense relationship to the property of nuclear matter. At the same time, we study the relation between the binding energy and pressure of relativistic Delta -resonance nuclear matter and temperature using above results in the relativistic sigma-omega-pi model, and it is interesting to compare it to our prior work. In all these studies, the vacuum fluctuation on nucleon, Delta -isobar, and sigma meson is considered.

Research paper thumbnail of Smoothing noisy spectroscopic data with many-knot spline method

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2008

In this paper, we present the development of a many-knot spline method derived to remove the stat... more In this paper, we present the development of a many-knot spline method derived to remove the statistical noise in the spectroscopic data. This method is an expansion

Research paper thumbnail of Iterative estimation of the background in noisy spectroscopic data

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2009

ABSTRACT In this paper, we present an iterative filtering method to estimate the background of no... more ABSTRACT In this paper, we present an iterative filtering method to estimate the background of noisy spectroscopic data. The proposed method avoids the calculation of the average full width at half maximum (FWHM) of the whole spectrum and the peak regions, and it can estimate the background efficiently, especially for spectroscopic data with the Compton continuum.

Research paper thumbnail of Correlated noises in an absorptive optical bistable model

The European Physical Journal B, 2006

We study the steady state properties of an absorptive optical bistable model in the presence of c... more We study the steady state properties of an absorptive optical bistable model in the presence of correlated noises. Based on the corresponding Fokker-Planck equation the steady state solution of the probability distribution and the average value of the transmitted light have been investigated. We have found that fluctuations of the input light amplitude improve the transmitted light and an optimized value exists for the fluctuations of the population difference at which the transmitted light takes its maximum value. The correlation between the two noises reduce the transmitted light and the noises in the model can induce a phase transition.

Research paper thumbnail of The collective excitation spectra of sigma , omega mesons in the Walecka model of nuclear matter

Journal of Physics G: Nuclear and Particle Physics, 1995

ABSTRACT

Research paper thumbnail of Gamma-ray detector on board lunar mission Chang’E-1

Advances in Space Research, 2008

Gamma-ray spectrometer (GRS) is included in the payload of Chinese first lunar mission Chang'E-1 ... more Gamma-ray spectrometer (GRS) is included in the payload of Chinese first lunar mission Chang'E-1 that will be launched in 2007. Specific objectives of the GRS are to map abundance of O, Si, Fe, Ti, U, Th, K, and perhaps, Mg, Al, and Ca to depths of about 20 cm. There are remarkable advantages for GRS application to remote sensing elemental materials over the entire lunar surface: large effective area and good ability for background rejection. We will describe the design of GRS and present its performance in this paper. Moreover, the GRS calibration will also be introduced.

Research paper thumbnail of 25aSH-9 Δ-hole励起の相対論的取り扱いとπ-凝縮

日本物理学会講演概要集, Sep 13, 1999

Research paper thumbnail of The Collective Excitation Spectra of $ sigma, omega$ and $ pi$ Mesonsin Nuclear Matter

The recent progress on the study of the collective excitation in relativistic nuclear matter is r... more The recent progress on the study of the collective excitation in relativistic nuclear matter is reviewed. The collective excitation modes are derived by meson propagators in nuclear matter. The mesons we study are σ, ω, γ and π mesons. For pion, we derived not only the relativistic particle -hole, deltahole excitations but also antiparticle excitations , such as particle -antiparticle, antidelta -particle, delta -antiparticle excitations. By calculating the dispersion relation and the spin -isospin dependent response function, the effects of all these excitation are studied.

Research paper thumbnail of Pion Propagator in the Chiral σ Model of Nuclear Matter

Communications in Theoretical Physics, 1995

Research paper thumbnail of Effect of the Poiseuille flow through the stenosed arteries on wall shear stress

Research paper thumbnail of Ρ0,Ω Multi-Π Decay and Ρ0-Ω Mixing Effect

Research paper thumbnail of Energy of the gravitational field of slowly rotating neutron stars

Chinese Journal of Physics- Taipei-

Using the Einstein-Tolman expression. for the energy-momentum pseudo-tensor, the energy density o... more Using the Einstein-Tolman expression. for the energy-momentum pseudo-tensor, the energy density of the gravitational field of slowly rotating neutron stars was calculated in Cartesian coordinates. The energy density of the gravitational field could be expressed by the metric of the non-rotating neutron star and the angular velocity of the local inertial frames, accurate to the first order in the angular velocity of the star. A numerical method for calculating the energy density is given.

Research paper thumbnail of Muscle's Motion in an Overdamped Regime

Communications in Theoretical Physics, 2002

ABSTRACT

Research paper thumbnail of The Influence of the Renormalization Condition to the Equation of State of the Nuclear Matter

Communications in Theoretical Physics, 2001

ABSTRACT In the relativistic sigma-omega model, the influences of the parameters b, c, d in the p... more ABSTRACT In the relativistic sigma-omega model, the influences of the parameters b, c, d in the potential U(sigma) = (1/2!)b sigma (2) + (1/3!)c sigma (3) + (1/4!)d sigma (4) to the incompressibility, effective mass and binding energy of the nuclear matter are studied in detail. The calculation of equation of state of nuclear matter shows that the values of b, c, d depend on the renormalization condition, we also find that a soft equation of state of nuclear matter can be obtained in a suitable renormalization condition, and the experimental incompressibility coefficient can be reproduced. These results are also used to study the thermal properties of hot Delta -resonant nuclear matter.

Research paper thumbnail of Properties of Rotating Neutron Stars in the Relativistic σ-ω Model

Communications in Theoretical Physics, 2004

ABSTRACT The properties such as the moment of inertia, the surface redshift and the radius of gyr... more ABSTRACT The properties such as the moment of inertia, the surface redshift and the radius of gyration of rotating neutron stars in the relativistic sigma-omega model are studied with the Hartle's method. The relation between the angular velocity of the fluid relative to the local inertial frame and the uniform angular velocity relative to the infinite is calculated.

Research paper thumbnail of Tachyon Pole in sigma Meson Propagator in Nuclear Matter in the Relativistic sigma-omega Model

COMMUNICATIONS IN THEORETICAL …, 2001

... in quantum hadron dynamics,[1] and great efforts have been made to study it.[2,3] In meson-nu... more ... in quantum hadron dynamics,[1] and great efforts have been made to study it.[2,3] In meson-nucleon field theory, the large coupling constants are in-volved, and the mass corresponding to the tachyon pole of the meson propagators is of the same order as the nu-cleon mass ...

Research paper thumbnail of Facilitated movement of inertial Brownian motors driven by a load under an asymmetric potential

Research paper thumbnail of Exactly solvable single lane highway traffic model with tollbooths

Physica A: Statistical Mechanics and its Applications, 2002

Tolls are collected on many highways as a means of traffic control and revenue generation. Howeve... more Tolls are collected on many highways as a means of traffic control and revenue generation. However, the presence of tollbooths on highway surely slows down traffic flow. Here, we investigate how the presence of tollbooths affect the average car speed using a simple-minded single lane deterministic discrete traffic model. More importantly, the model is exactly solvable.

Research paper thumbnail of Stochastic resonance in a stochastic bistable system

Journal of Statistical Mechanics: Theory and Experiment, 2007

ABSTRACT

Research paper thumbnail of A channel Brownian pump powered by an unbiased external force

The Journal of Chemical Physics, 2008

A Brownian pump of particles in an asymmetric finite tube is investigated in the presence of an u... more A Brownian pump of particles in an asymmetric finite tube is investigated in the presence of an unbiased external force. The pumping system is bounded by two particle reservoirs. It is found that the particles can be pumped through the tube from a reservoir at low concentration to one at the same or higher concentration. There exists an optimized value of temperature (or the amplitude of the external force) at which the pumping capacity takes its maximum value. The pumping capacity decreases with increasing radius at the bottleneck of the tube.

Research paper thumbnail of Influence of self interaction of σ meson to the equation of state of nuclear matter

High Energy Physics and Nuclear Physics -Beijing-

In the relativistic sigma-omega model, the influence of the parameters in self-interaction of sig... more In the relativistic sigma-omega model, the influence of the parameters in self-interaction of sigma meson to the equation of state of normal nuclear matter, especially, to incompressibility, effective mass, and coupling constants, is studied in detail. We find that these parameters have an intense relationship to the property of nuclear matter. At the same time, we study the relation between the binding energy and pressure of relativistic Delta -resonance nuclear matter and temperature using above results in the relativistic sigma-omega-pi model, and it is interesting to compare it to our prior work. In all these studies, the vacuum fluctuation on nucleon, Delta -isobar, and sigma meson is considered.

Research paper thumbnail of Smoothing noisy spectroscopic data with many-knot spline method

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2008

In this paper, we present the development of a many-knot spline method derived to remove the stat... more In this paper, we present the development of a many-knot spline method derived to remove the statistical noise in the spectroscopic data. This method is an expansion

Research paper thumbnail of Iterative estimation of the background in noisy spectroscopic data

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2009

ABSTRACT In this paper, we present an iterative filtering method to estimate the background of no... more ABSTRACT In this paper, we present an iterative filtering method to estimate the background of noisy spectroscopic data. The proposed method avoids the calculation of the average full width at half maximum (FWHM) of the whole spectrum and the peak regions, and it can estimate the background efficiently, especially for spectroscopic data with the Compton continuum.

Research paper thumbnail of Correlated noises in an absorptive optical bistable model

The European Physical Journal B, 2006

We study the steady state properties of an absorptive optical bistable model in the presence of c... more We study the steady state properties of an absorptive optical bistable model in the presence of correlated noises. Based on the corresponding Fokker-Planck equation the steady state solution of the probability distribution and the average value of the transmitted light have been investigated. We have found that fluctuations of the input light amplitude improve the transmitted light and an optimized value exists for the fluctuations of the population difference at which the transmitted light takes its maximum value. The correlation between the two noises reduce the transmitted light and the noises in the model can induce a phase transition.

Research paper thumbnail of The collective excitation spectra of sigma , omega mesons in the Walecka model of nuclear matter

Journal of Physics G: Nuclear and Particle Physics, 1995

ABSTRACT

Research paper thumbnail of Gamma-ray detector on board lunar mission Chang’E-1

Advances in Space Research, 2008

Gamma-ray spectrometer (GRS) is included in the payload of Chinese first lunar mission Chang'E-1 ... more Gamma-ray spectrometer (GRS) is included in the payload of Chinese first lunar mission Chang'E-1 that will be launched in 2007. Specific objectives of the GRS are to map abundance of O, Si, Fe, Ti, U, Th, K, and perhaps, Mg, Al, and Ca to depths of about 20 cm. There are remarkable advantages for GRS application to remote sensing elemental materials over the entire lunar surface: large effective area and good ability for background rejection. We will describe the design of GRS and present its performance in this paper. Moreover, the GRS calibration will also be introduced.

Research paper thumbnail of 25aSH-9 Δ-hole励起の相対論的取り扱いとπ-凝縮

日本物理学会講演概要集, Sep 13, 1999

Research paper thumbnail of The Collective Excitation Spectra of $ sigma, omega$ and $ pi$ Mesonsin Nuclear Matter

The recent progress on the study of the collective excitation in relativistic nuclear matter is r... more The recent progress on the study of the collective excitation in relativistic nuclear matter is reviewed. The collective excitation modes are derived by meson propagators in nuclear matter. The mesons we study are σ, ω, γ and π mesons. For pion, we derived not only the relativistic particle -hole, deltahole excitations but also antiparticle excitations , such as particle -antiparticle, antidelta -particle, delta -antiparticle excitations. By calculating the dispersion relation and the spin -isospin dependent response function, the effects of all these excitation are studied.

Research paper thumbnail of Pion Propagator in the Chiral σ Model of Nuclear Matter

Communications in Theoretical Physics, 1995

Research paper thumbnail of Effect of the Poiseuille flow through the stenosed arteries on wall shear stress

Research paper thumbnail of Ρ0,Ω Multi-Π Decay and Ρ0-Ω Mixing Effect