Effects Of Intense Magnetic Fields Research Articles

Enhancement of Elliptic Flow of π− under Intense Magnetic Field in √ sNN = 200 GeV Au+Au Collisions: A (2 + 1)-Dimensional Reduced-MHD Model Study

We investigate the effect of intense magnetic fields on the ( 2 + 1 ) -dimensional reduced- magnetohydrodynamical (MHD) expansion of hot and dense quark–gluon plasma (QGP) produced in s NN = 200 GeV Au+Au collisions. For the sake of simplicity, we consider the case in which the magnetic field points in the direction perpendicular to the reaction plane. We also consider this field to be external, with energy density parametrized as a two-dimensional Gaussian. The width of the Gaussian along the directions orthogonal to the beam axis varies with the centrality of the collision. The dependence of the magnetic field on proper time ( τ ) is parametrized for the case of zero and finite electrical conductivity of the QGP. We solve the equations of motion of ideal hydrodynamics for such an external magnetic field. For collisions with a non-zero impact parameter we observe a considerable increase in the elliptic-flow coefficient v 2 of π − in the presence of an external magnetic field, and the increment in v 2 is found to depend on the evolution and the initial magnitude of the magnetic field.

Cold quark matter phase diagram under strong magnetic fields within a generalized SU(2) NJL model

We study the effect of intense magnetic fields on the phase diagram of cold, strongly interacting matter within an extended version of the Nambu-Jona-Lasinio model that includes flavor mixing effects and vector interactions. Different values of the relevant model parameters in acceptable ranges are considered. Charge neutrality and beta equilibrium effects, which are specially relevant to the study of compact stars, are also taken into account. In this case the behavior of leptons is discussed.

Cold quark matter under intense magnetic fields: the role of flavor mixing and vector interactions

We study the effect of intense magnetic fields on the phase diagram of cold, strongly interacting matter within the Nambu-Jona-Lasinio model. Model extensions that include flavor mixing effects and vector interactions were analyzed, varying all relevant model parameters in acceptable ranges. Charge neutrality and beta equilibrium effects, which are specially relevant to the study of compact stars, were also considered.

Cold magnetized quark matter phase diagram within a generalized SU(2) NJL model

We study the effect of intense magnetic fields on the phase diagram of cold, strongly interacting matter within an extended version of the Nambu-Jona-Lasinio model that includes flavor-mixing effects and vector interactions. Different values of the relevant model parameters in acceptable ranges are considered. Charge neutrality and beta equilibrium effects, which are especially relevant to the study of compact stars, are also taken into account. In this case, the behavior of leptons is discussed.

Effect of intense magnetic fields on the convection of biogenic guanine crystals in aqueous solution

In this study, the basic magneto-optic properties of biogenic microcrystals in aqueous media were investigated. Microcrystals, mica plates, silica, and microcrystals from a diatom cell and biogenic guanine crystals from goldfish showed light scattering inhibition when the crystals were observed in water under a 5 T magnetic field and dark-field illumination. In particular, in 50% ethanol/water medium, convection of the biogenic guanine particle aggregates was reversibly inhibited when the microcrystal suspension was exposed to a 5 T magnetic field. Microscopic observation comparing the biogenic guanine crystals in water with 95% ethanol or 99% acetone revealed that light flickering on the surface of the crystals was affected by the surface interaction of the crystal with the surrounding medium. By considering both the magnetic orientation of the microcrystals and the possible interactions of crystals with the surrounding medium, a magnetically controllable fluidic tracer was suggested.

Strongly interacting matter under extreme conditions: The effect of intense magnetic fields

AbstractWe study the effects of magnetic fields on the phase diagram of strongly interacting matter using the Nambu‐Jona‐Lasinio model and its finite temperature extension which includes a coupling to the Polyakov loop. Emphasis is laid on the phase structure and its dependence on the parameters defining the model. We consider two parameter sets showing that they lead to rather different results, especially at low temperatures. The phenomena of magnetic catalysis and its counterpart, magnetic anti‐catalysis, are also discussed. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

The effects of intense magnetic fields on Landau levels in a neutron star

In this paper, an approximate method of calculating the Fermi energy of electrons ($E_{F}(e)$) in a high-intensity magnetic field, based on the analysis of the distribution of a neutron star magnetic field, has been proposed. In the interior of a Neutron star, different forms of intense magnetic field could exist simultaneously and a high electron Fermi energy could be generated by the release of magnetic field energy. The calculation results show that: $E_{F}(e)$ is related to density $\rho$, the mean electron number per baryon $Y_{e}$ and magnetic field strength $B$.

Magnetic field effects on near-infrared optical properties of cytochrome oxidase

This paper reports the possible effects of intense magnetic fields on the near-infrared optical properties of cytochrome oxidase. Optical measurements performed on both cytochrome aa3 suspension and in vivo showed changes in optical absorbance at 690–830 nm under magnetic field exposure. Magnetic fields of up to 14 T generated by a superconducting current were able to change the oxidation of the oxidized cytochrome aa3 periodically depending on the density of the magnetic flux. Measurements with a cooled CCD system revealed that the absorbance at 830 nm was slightly increased by a magnetic field of 8 T. We performed an animal experiment on the head of a living rabbit, and obtained results showing the enhancement of cytochrome aa3 oxidation in the mitochondria of cells under the magnetic fields. The effects of magnetic fields on the paramagnetic behavior of oxygen, electron transfer in cytochromes, and cell membrane conformation in mitochondria may playa role in increasing the sensitivity to NIR light for detecting cyto-ox oxidation, which is one of the primary indicators of cellular activity.

On the orbital period modulation of RS CVn binary systems

The Applegate hypothesis proposed to explain the orbital period modulation of RS Canum Venaticorum (RS CVn) close binaries (Applegate 1992) is considered in the framework of a general model to treat the angular momentum exchanges within the convective envelope of a magnetically active star. This model assumes that the convection zone is strictly adiabatic and that the Taylor-Proudman balance holds, leading to an internal angular velocity constant over cylindrical surfaces co-axial with the rotation axis. It turns out that the angular velocity perturbations, whatever their origin, can be expressed in terms of the eigenfunctions of the equation of angular momentum conservation with stress-free boundary conditions. Moreover, a lower limit for the energy dissipation rate in a turbulent convection zone can be set, thanks to the extremal properties of the eigenfunctions. This approach allows to apply precise constraints on the amplitude and the radial profile of the angular velocity variations that are required to explain the observed orbital period changes in classical RS CVn binaries (i.e. with orbital period longer than 1-2 d and a subgiant secondary component). It is found that an angular velocity change as large as 10 per cent of the unperturbed angular velocity at the base of the stellar convection zone is needed. Such a large change is not compatible with the observations. Moreover, it would produce an energy dissipation rate much larger than the typical luminosities of the active components of RS CVn systems, except in the case that fast rotation and internal magnetic fields reduce the turbulent viscosity by at least 2 orders of magnitude with respect to the value given by the mixing-length theory. Therefore, the model proposed by Applegate should be rejected, at least in the case of classical RS CVn close binaries. Possible alternative models are briefly discussed, emphasizing the effects of intense magnetic fields (∼ 10 T) on the internal structure of magnetically active stars and the dynamics of close binary systems.

Effects of intense magnetic fields on sedimentation pattern and gene expression profile in budding yeast

Effects of magnetic fields (MFs) on biological systems are usually investigated using biological indices such as gene expression profiles. However, to precisely evaluate the biological effects of MF, the effects of intense MFs on systematic material transport processes including experimental environment must be seriously taken into consideration. In this study, a culture of the budding yeast, Saccharomyces cerevisiae, was used as a model for an in vitro biological test system. After exposure to 5 T static vertical MF, we found a difference in the sedimentation pattern of cells depending on the location of the dish in the magnet bore. Sedimented cells were localized in the center of the dish when they were placed in the lower part of the magnet bore while the sedimentation of the cells was uniform in dishes placed in the upper part of the bore because of the diamagnetic force. Genome wide gene expression profile of the yeast cells after exposure to 5 T static MF for 2 h suggested that the MF did not affect the expression level of any gene in yeast cells although the sedimentation pattern was altered. In addition, exposure to 10 T for 1 h and 5 T for 24 h also did not affect the gene expression. On the other hand, a slight change in expressions of several genes which are related to respiration was observed by exposure to a 14 T static MF for 24 h. The necessity of estimating the indirect effects of MFs on a study of its biological effect of MF in vitro will be discussed.

Aggregation of blood platelets in static magnetic fields

We investigated the effects of intense magnetic fields on the blood platelet aggregation process with and without static magnetic fields of up to 14 T. A rabbit plasma and collagen mixture was used as the model system for a wounded blood vessel. Platelet aggregation was activated by the stimulation of acid soluble collagen. The platelet aggregates in strong magnetic fields were larger than the aggregates in an ambient field. An optical transmission of blood plasma during platelet aggregation also indicated that strong magnetic fields enhanced blood platelet aggregation in plasma.

Effect of strong magnetic field on cosmic quark-hadron phase transition and baryon inhomogeneity

The effect of intense magnetic field on the cosmic quark-hadron phase transition and also on the baryon number inhomogeneity has been investigated using phenomenological MIT bag model for the quark sector. For the sake of simplicity an ideal gas equation of state has been considered for the hadronic phase.

A laser flash photolysis study of the effect of intense magnetic fields on the photoreaction of benzophenone in SDS micellar solution

The magnetic field dependence of the lifetime of the benzophenone ketyl-SDS-derived radical pair in SDS micellar solution is divided into three regions. In a low magnetic field (<0.3 T) the lifetime increases steeply, it exhibits a square dependence on the magnetic field strength between 0.3 and 2 T, and then becomes constant (2–14 T). The mechanism of the observed magnetic field dependence is discussed.

“Molecular Properties” in Intense Magnetic Field

Abstract The simple LCAO method has been used to find the effect of intense magnetic fields on the internuclear distance and the binding energy of the H2 + ion. The Spruch functions of the Hydrogen atom have been chosen as the basis. The results show that the magnetic pressure greatly affects the internuclear distance and the bonding energy. Req and Ebind as a function of α, the classical cyclotron radius of the electron, are given.

HFE degradation in the presence of intense magnetic fields

A theory was worked out to analyze the effect of intense magnetic fields on the forward current gain hFE. The quantum splitting of energy levels (Landau levels) was utilized. The theory is in very good agreement with available experimental data.

Effect of a Constant Magnetic Field on the Neutron Beta Decay Rate and its Astrophysical Implications

RECENT advances in the production of large magnetic fields in the laboratory1,2 have generated interest in the effect of intense magnetic fields on various phenomena3,4. The largest field that can be produced in the laboratory1,2 at present is about 106 G, which is considerably lower than the quantum critical field value5 of Hc = m2c3/eV = 4.4 × 1013 G; but the “cosmic laboratory” may be a source of much stronger fields and it has been suggested6 that magnetic fields as large as 1014−1016 G may exist in neutron stars. Hoyle7 has cited the possibility of a large primordial magnetic field, and Brownell and Callaway8 speculate that neutron stars and the dense early universe may be ferromagnetic. One of us (R. F. O.) has examined9 various effects of a large magnetic field and has indicated an effect of magnetic fields which has been often ignored in astrophysical investigations, namely, that the rates of all elementary particle processes will be affected. Pursuing this idea, we examine here the effect of a magnetic field on the β decay rate of a neutron. This is a fundamental process in many astrophysical phenomena and in particular it is very important10 in a problem of current interest, that is, the production of He in the “big-bang” expansion of the universe11. In addition, our calculations should be applicable to other elementary particle processes. We present here only the main ideas ; the calculation details will be published elsewhere12.

The Effect of Intense Magnetic Fields on Electroluminescent Powder Phosphors

The effect of intense magnetic fields on electroluminescent powder phosphors is investigated to furnish information which should be helpful in developing a theory of the mechanism of electroluminescence. No quenching effect was observed even for magnetic field intensities as high as 1.3 × 105 oersteds. The significance of this result is discussed.