Interfering and interferon-inducing capacity of NDV

Shu, Han

doi:10.1007/bf01240060

Cited by 2 publications

(12 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Our results are also important for determining the conditions under which the Parker instability can operate in the interstellar medium (ISM). Previous treatments of the Parker instability assume an adiabatic thermal plasma (Parker 1966(Parker , 1967Shu 1974;Ryu et al 2003). Our results show that anisotropic thermal conductivity makes the ISM more unstable to the Parker instability, so that the instability can operate under a wider range of equilibrium profiles than was previously recognized.…”

Section: No 1 2009 Parker/buoyancy Instabilities 567mentioning

confidence: 53%

“…As a check on the results of this section, we show in Appendix B that Equation (47) reduces properly to the results obtained by Parker (1966Parker ( , 1967 and Shu (1974) when cosmicray diffusivity is taken to be infinite and thermal conduction is negligible, and when the results of Parker (1966Parker ( , 1967 and Shu (1974) are considered in the short-wavelength limit.…”

Section: The General Dispersion Relationmentioning

confidence: 69%

“…We focus on wave vectors in the "quasi-interchange" limit, in which |k x | |k y |, |k x | |k z |, and |k x H | 1, where H is the density scale height. This is the most unstable wave-vector regime for stratified adiabatic plasmas, because a small k y reduces the stabilizing effects of magnetic tension and a large k x allows a rising fluid element to easily get out of the way of the next rising element beneath it by moving just a small distance in the x-direction (Parker 1967;Shu 1974;Ferriere et al 1999). We show analytically that the stability criterion in this limit is nk B dT dz + dp cr dz…”

Section: No 1 2009 Parker/buoyancy Instabilities 567mentioning

confidence: 93%

“…The most unstable modes in a gravitationally stratified adiabatic plasma threaded by a horizontal magnetic field are those for which |k x | is very large, so that (Parker 1967;Shu 1974;Ferriere et al 1999). We conjecture that the same is true when thermal conduction is taken into account, at least when the equilibrium magnetic field is horizontal, and thus we focus on this limit, which we call the "quasi-interchange limit."…”

Section: The Quasi-interchange Limitmentioning

confidence: 94%

“…Standard analyses of the Parker instability consider an equilibrium in which g = −gẑ, B is in the xy-plane, ρ ∝ exp(−z/H ), and H, T, β, and p cr /p are constant (Parker 1966(Parker , 1967Shu 1974;Ryu et al 2003). In early studies, the parallel cosmic-ray diffusion coefficient D was taken to be infinite, since p cr was assumed to be constant along magnetic field lines (Parker 1966(Parker , 1967Shu 1974). On the other hand, Ryu et al (2003) considered the effects of finite D , as well as cosmic-ray diffusion perpendicular to magnetic field lines.…”

Section: The Parker Instability In the Ismmentioning

confidence: 99%

See 4 more Smart Citations

Parker/Buoyancy Instabilities With Anisotropic Thermal Conduction, Cosmic Rays, and Arbitrary Magnetic Field Strength

Dennis

Chandran

2008

ApJ

View full text Add to dashboard Cite

We report the results of local stability analysis for magnetized, gravitationally stratified plasma-containing cosmic rays. We account for cosmic-ray diffusion and thermal conduction parallel to the magnetic field and allow β = 8πp/B 2 to take any value, where p is the plasma pressure and B is the magnetic field strength. We take the gravitational acceleration to be in the −z-direction and the equilibrium magnetic field to be in the y-direction, and derive the dispersion relation for small-amplitude instabilities and waves in the large-|k x | limit. We use the Routh-Hurwitz criterion to show analytically that the necessary and sufficient criterion for stability in this limit is nk B dT /dz + dp cr /dz + (1/8π ) dB 2 /dz > 0, where T is the temperature, n is the number density of thermal particles, and p cr is the cosmic-ray pressure. We present approximate analytical solutions for the normal modes in the low-and high-diffusivity limits, show that they are consistent with the derived stability criterion, and compare them to numerical results obtained from the full, unapproximated, dispersion relation. Our results extend earlier analyses of buoyancy instabilities in galaxycluster plasmas to the β 1 regime. Our results also extend earlier analyses of the Parker instability to account for anisotropic thermal conduction, and show that the interstellar medium is more unstable to the Parker instability than was predicted by previous studies in which the thermal plasma was treated as adiabatic.

show abstract

Section: No 1 2009 Parker/buoyancy Instabilities 567mentioning

confidence: 53%