Search

The conventional quark mass is not continuous at thresholds. In this paper, we derive matchinginvariant quark masses which are continuous everywhere. They are expanded as an obvious function of the logarithmic Lambda scaled energy. The expansion coefficients are related to the original gamma and beta functions, with concretization to four loop level. The results show that the new expressions for the quark masses converge indeed much faster.

The properties of strangelets at finite temperature are studied within the framework of an equivparticle model, where a new quark mass scaling and self-consistent thermodynamic treatment are adopted. The effects of finite volume and Coulomb energy are taken into account. Our results show that the temperature T, baryon number A and perturbation interactions have strong influences on the properties of strangelets. It is found that the energy per baryon M/A and charge-to-mass ratio fz decrease with baryon number A, while the mechanically stable radius R and strangeness per baryon fs are increasing. For a strangelet with a fixed baryon number, we note that as temperature T increases the quantites M/A, R, and fs are increasing while fz is decreasing. The effects of confinement and perturbative interactions are investigated as well by readjusting the corresponding parameters.

The properties of strange quark matter and the structures of (proto-)strange stars are studied within the framework of an equivparticle model, where a new quark mass scaling and self-consistent thermodynamic treatment are adopted. Our results show that the perturbative interaction has a strong impact on the properties of strange quark matter. It is found that the energy per baryon increases with temperature, while the free energy decreases and eventually becomes negative. At fixed temperatures, the pressure at the minimum free energy per baryon is zero, suggesting that the thermodynamic self-consistency is preserved. Additionally, the sound velocity v in quark matter approaches to the extreme relativistic limit (c/sqrt(3)) as the density increases. By increasing the strengths of confinement parameter D and perturbation parameter C, the tendency for v to approach the extreme relativistic limit at high density is slightly weakened. For (proto-)strange stars, in contrast to the quark mass scalings adopted in previous publications, the new quark mass scaling can accommodate massive proto-strange stars with their maximum mass surpassing twice the solar mass at T = 50 MeV.

We used the blast wave model with Boltzmann Gibbs statistics and analyzed the experimental data measured by NA61/SHINE Collaboration in inelastic (INEL) proton-proton collisions at different rapidity slices at different center-of-mass energies. The particles used in this study are pion, kaon, proton and anti-proton. We extracted kinetic freeze-out temperature, transverse flow velocity and kinetic freeze-out volume from the transverse momentum spectra of the particles. We observed that the kinetic freeze-out temperature is rapidity and energy dependent, while transverse flow velocity does not depend on them. Furthermore, we observed that the kinetic freeze-out volume is energy dependent but it remains constant with changing the rapidity. We also observed that all these three parameters are mass dependent. In addition, with the increase of mass, the kinetic freeze-out temperature increases, and the transverse flow velocity as well as kinetic freeze-out volume decreases.

A generalized quantum search algorithm, where phase inversions for the marked state and the prepared state are replaced by $\pi/2$ phase rotations, is realized in a 2-qubit NMR heteronuclear system. The quantum algorithm searches a marked state with a smaller step compared to standard Grover algorithm. Phase matching requirement in quantum searching is demonstrated by comparing it with another generalized algorithm where the two phase rotations are $\pi/2$ and $3\pi/2$ respectively. Pulse sequences which include non 90 degree pulses are given., Comment: 12 pages, 2 figures, accepted for publication in Plysics Letters A

The quantum nature of bulk ensemble NMR quantum computing --the center of recent heated debate, is addressed. Concepts of the mixed state and entanglement are examined, and the data in a 2 qubit liquid NMR quantum computation are analyzed. It is pointed out that the key problem in the current debate is the understanding of entanglement in a mixed state system. The following points are concluded in this Letter: 1)Density matrix describes the "state" of an average particle in an ensemble. It can not describe the state of an individual particle in an ensemble in detail; 2) Entanglement is a property of the wave function of a quantum particle(such as an molecule in a liquid NMR sample). Separability of the density matrix can not be used to measure the entanglement of mixed ensemble; 3)The evolution of states in bulk-ensemble NMR quantum computation is quantum mechanical; 4) The coefficient before the effective pure state density matrix, $\epsilon$, is an measure of the simultaneity of the molecules in an ensemble. It reflects the intensity of the NMR signal and has no significance in quantifying the entanglement in the bulk ensemble NMR system. We conclude that the liquid NMR quantum computation is genuine, not just classical simulations., Comment: 4 pages